4.4.2 Residential Handler Risk Assessment The anticipated use patterns and current labeling indicate 17 major residential exposure scenarios, based on the types of equipment and techniques, in which homeowners can be exposed to 5 PHED is a generic database, which includes the results of over 100 exposure studies, developed by US EPA, Pest Management Regulatory Agency/ Health Canada and the California Department of Pesticide Regulation, in cooperation with the pesticide industry.

46 carbaryl during the application process. The quantitative exposure/ risk assessment developed for residential handlers is based on these scenarios. For most scenarios, multiple uses and application rates were considered for a total of 54 distinct combinations. The 17 major scenarios include:

(1) Garden Uses: Ready to use Trigger Sprayer; (2) Garden Uses: Ornamental Duster; (3) Garden Uses: Hose end Sprayer; (4) Garden Uses: Low Pressure Handwand; (5) Tree/ ornamental Uses: Low Pressure Handwand; (6) Tree/ ornamental Uses: Hose end Sprayer; (7) Garden Uses: Backpack Sprayer; (8) Lawncare Liquid Uses: Hose end Sprayer; (9) Pet (Dog and Cat) Uses: Dusting; (10) Pet (Dog and Cat) Uses: Liquid Application; (11) Lawncare Granular and Bait Uses: Belly Grinder; (12) Lawncare Granular and Bait Uses: Push type Spreader; (13) Ornamental and Garden Uses: Granulars and Baits By Hand; (14) Various Pest Uses: Aerosol Cans; (15) Pet (Dog and Cat) Uses: Collars; (16) Garden and Ornamental Uses: Sprinkler Can; and (17) Garden and Ornamental Uses: Paint on.

Data and Assumptions A series of assumptions and exposure factors served as the basis for completing the residential handler risk assessments, as described below.

° The unit exposure values used in this assessment were based on three carbaryl specific residential handler studies which quantified exposures during pet treatments with a dust; applications to gardens using a ready to use trigger sprayer, a dust, a hose end sprayer, and a low pressure handwand; and during applications to trees using a low pressure handwand and a hose end sprayer. Two other studies completed by the Outdoor Residential Exposure Task Force (ORETF) and the Pesticide Handlers Exposure Database (Version 1.1 August 1998) (PHED) 5 were also used as sources of surrogate information. [Note to Risk Managers: There is no data compensation issue associated with the use of the ORETF data in the carbaryl risk assessment because Aventis CropScience, the registrant for carbaryl, is a member of the ORETF]. Summaries of the five studies are included in the Occupational and Residential Risk Assessment (D281418). These studies are all considered to be of high quality. The quality of the data in PHED varies from scenarios that meet study guideline requirements to others where a limited number of poor quality data points are available. However, in all cases, the data used represent the best available for the scenario. The PHED unit exposure values range between geometric mean and median of available exposure data. When data from other studies were used, the 47 appropriate statistical measure of central tendency was used. Central tendency values, coupled with other inputs used by HED, are thought to result in conservative, deterministic estimates of risk. For pet collars only, a scenario from the SOPs For Residential Exposure Assessment not based on monitoring data was used to calculate exposures. The factors derived from the SOPs are generally thought to be conservative.

° Average body weight of adult handlers is assumed to be 70 kg because the toxicology endpoint values used for the risk assessments are appropriate for average adult body weight representing the general population. No specific effects were observed consistently in the toxicology studies to indicate an increased sensitivity of one gender over another.

° Homeowner handler assessments were completed based on individuals wearing shorts and shortsleeved shirts.

° Homeowner handlers are expected to complete all tasks associated with the use of a pesticide product including mixing/ loading, if needed, as well as the application;

° Label maximum use rates and use information specific to residential products served as the basis for the risk calculations. If additional information, such as average or typical rates, were available, these values were used as well in order to allow risk managers to make a more informed risk management decision. Average application rates were available from the SMART meeting and BEAD's Quantitative Usage Analysis (QUA). These data indicate that in most cases, average application rates differ from maximum application rates by a factor of approximately two. The average application rates identified from the studies conducted by Aventis CropScience were also considered.

° The exposure duration (i. e., years per lifetime) values in the cancer risk assessment are consistent with those used for other chemicals (i. e., 50 years with home use chemicals and 70 year lifetime). Cancer risks were calculated assuming one exposure per year. In addition the number of days of exposure per year which could occur under the ceiling established by an acceptable risk level of 1x10 6 were also calculated. These estimates can then be compared to the annual use frequency of 1 2x (60 th percentile) and 5x (84 th percentile) presented at the SMART meeting. [Note: It is the understanding of the Agency that Aventis Crop Science is also submitting a use analysis based on the Residential Exposure Joint Venture (REJV) survey which could possibly refine these estimates. The Agency will consider these data as appropriate.] 48 ° Calculations were based on scenarios in the home that would reasonably be treated in a day (but would not necessarily take more than an hour or two) such as the size of a lawn, the size of a garden, the amount that can be applied with a piece of equipment, or the number of pets an individual might keep. Based on Agency Exposure SAC Policy 12: Recommended Revisions To The Standard Operating Procedures For Residential Exposure Assessment, the daily volumes handled and area treated, excerpted from the policy, used in each residential scenario include (along with corresponding inputs defined from carbaryl studies and the SMART meeting for a comparative analysis to allow for a more informed risk management decision):

° 1 container of each ready to use non pet product including garden dusts, trigger sprayers and aerosol cans (scenarios for 25% and 50% used of the total product volume were also presented for the trigger sprayer and garden dust scenarios to allow for a more informed risk management decision); ° ½ container of each ready to use pet product, including dusts and liquid shampoos; ° 1 pet collar; ° 100 gallons of finished spray output for hose end sprayers; ° 5 gallons when mixing/ loading/ applying liquids with a backpack sprayer or a low pressure handwand sprayer; value was also used for sprinkler can applications; ° 1 gallon of paint on solution for ornamental/ garden uses; ° 20,000 square feet to represent the surface area treated for broadcast applications to lawns; ° 1000 square feet as the treatment area for many spot applications in lawns, gardens, and ornamentals (this value used as appropriate when application rates were based on a square foot basis for spot type treatments); and ° 5 mounds per day treated for fire ant applications.

° For direct pet treatments, the Residential SOPs were used to define the amount of chemical that can be used to treat single animals, which was then used to calculate total human dose levels. The actual per animal application rates used were ½ of 6 oz. bottle for liquid shampoo (0.5%) and ½ of 4 lb. container for powders (10%).

<IP_ADDRESS> Residential Handler Noncancer Risks Noncancer risks were calculated using the Margin of Exposure (MOE) approach, which is a ratio of the body burden (exposure) to the toxicological endpoint of concern. Short term dermal MOEs were calculated using a NOAEL of 20.0 mg/ kg/ day from the 21 day dermal toxicity study in rats with technical material and short term inhalation MOEs were calculated using a NOAEL of 1 mg/ kg/ day from the oral developmental neurotoxicity study in rats. Body burden values were determined by first calculating daily exposures using application parameters (i. e., rate and area treated) along with unit exposure levels. Exposures were then normalized by body weight and adjusted for absorption factors (100 percent for both dermal and inhalation) as appropriate to calculate average daily dose levels (i. e., body burdens) as illustrated in equation below. 49 Daily Exposure (mg ai/ day) =

Unit Exposure (mg ai/ lb ai) x Application Rate (lb ai/ A) x Daily Acres Treated (A/ day)

Where:

Daily Exposure = Amount deposited on the surface of the skin that is available for dermal absorption or amount that is inhaled, also referred to as potential dose (mg ai/ day); Unit Exposure = Normalized exposure value derived from August 1998 PHED Surrogate Exposure Table and various referenced exposure studies noted above (mg ai/ lb ai); Application Rate = Normalized application rate based on a logical unit treatment such as acres or gallons, maximum and typical values are generally used (lb ai/ A); and Daily Acres Treated = Normalized application area based on a logical unit treatment such as acres (A/ day) or gallons per day can be substituted (gal/ day).

The dermal absorption factor of 100 percent based on an absorption study in rats was used for all dermal calculations since no route to route conversion was required. No specific inhalation absorption factor is available for carbaryl. Therefore, a factor of 100 percent was used for route to route calculations as is done with all pesticides. MOEs were calculated using the following formula.

MOE = NOAEL (mg ai/ kg/ day) Average Daily Dose (mg ai/ kg/ day)

Where:

MOE = Margin of exposure, value used to represent risk or how close a chemical exposure is to being a concern (unitless); Average Daily Dose = The amount as absorbed dose received from exposure to a pesticide in a given scenario (mg pesticide active ingredient/ kg body weight/ day); and NOAEL = No observed adverse effect level or dose level in a toxicity study where no observed adverse effects occurred in the study (mg pesticide active ingredient/ kg body weight/ day).

A combined (dermal and inhalation) MOE was determined because common toxicity (cholinesterase inhibition) endpoints were used to calculate dermal and inhalation risks for each exposure duration. The following formula was used to calculate total MOE values by combining the route specific MOEs:

MOE total = 1/(( 1/ MOE a) + (1/ MOE b) +.... (1/ MOE n))

Where: MOE a, MOE b, and MOE n represent MOEs for each exposure route of concern Short term risks for residential handlers (intermediate term scenarios are not thought to exist because of the sporadic nature of applications by homeowners) are presented in Table 11. For most scenarios (40 out of 52), risks are not of concern because MOEs exceed the required uncertainty factor of 100. As expected, the scenarios for which MOEs do not meet or exceed 100 have a relatively high unit exposure associated with them or the amount of chemical used over a day is relatively high (based on high application rates and/ or high amounts of area treated). The use of dusts in gardens and for pet 50 grooming along with some liquid sprays on ornamentals appear to be the most problematic scenarios. Unlike the occupational handler scenarios, the use of different levels of personal protective clothing and equipment is not considered for residential handlers because of a lack of availability, training, and maintenance. [Note: Scenarios where MOEs are of concern (i. e., <100) for are highlighted in the table.]

TABLE 11 CARBARYL NONCANCER MOEs ATTRIBUTABLE TO COMBINED SHORT TERM HOMEOWNER HANDLER DERMAL AND INHALATION EXPOSURES SCEN. SCEN. DESCRIPTOR CROP TYPE OR TARGET EXPOSURE FACTORS DERMAL MOEs INHALATION MOEs COMBINED MOEs APPL. RATE (lb ai/ unit) BASIS FOR RATE (defines unit treated) TREATED UNITS ACTIVE USED (lb ai/ event)

1 Garden: Ready to Use Trigger Sprayer (MRID 444598 01) Vegetables/ Ornamentals 0.003 32 oz bottle 0.126 % (769 977) 0.25 0.00075 34567.9 1393034.8 33730.9 Vegetables/ Ornamentals 0.003 32 oz bottle 0.126 % (769 977) 0.5 0.0015 17284.0 696517.4 16865.4 Vegetables/ Ornamentals 0.003 32 oz bottle 0.126 % (769 977) 1 0.003 8642.0 348258.7 8432.7 Average Study Use Rate 0.012 (lb ai/ 1000 ft2) 1 0.012 2160.5 87064.7 2108.2 2 Garden/ Ornamental Dust (MRID 444598 01) Vegetables/ Ornamentals 0.4 4 lb bottle 10% (239 1513) 0.25 0.1 94.6 804.6 84.6 Vegetables/ Ornamentals 0.4 4 lb bottle 10% (239 1513) 0.5 0.2 47.3 402.3 42.3 Vegetables/ Ornamentals 0.4 4 lb bottle 10% (239 1513) 1 0.4 23.6 201.1 21.2 Average Study Use Rate 0.079 (lb ai/ 1000 ft2) 1 0.079 119.7 1018.5 107.1 3 Garden: Hose End (MRID 444598 01) General Use (2% soln) 0.02 (lb ai/ gal spray applied) 100 2 20.6 17500.0 20.6 Perimeter Nuisance Pest 0.19 (lb ai/ 1000 ft2) 1 0.19 216.7 184210.5 216.5 Vegetables 0.012 (lb ai/ 1000 ft2) 1 0.012 3431.4 2916666.7 3427.3 Vegetables/ Ornamentals 0.023 (lb ai/ 1000 ft2) 1 0.023 1790.3 1521739.1 1788.2 Vegetables 0.047 (lb ai/ 1000 ft2) 1 0.047 876.1 744680.9 875.1 Average Study Use Rate 0.26 (lb ai/ 1000 ft2) 1 0.26 158.4 134615.4 158.2 Fire Ant 0.0075 (lb ai/ gal spray) 100 0.75 54.9 46666.7 54.8 4 Garden: Low Pressure Handwand (MRID 444598 01) General Use (2% soln) 0.02 (lb ai/ gal spray applied) 5 0.1 368.4 77777.8 366.7 Perimeter Nuisance Pest 0.19 (lb ai/ 1000 ft2) 1 0.19 193.9 40935.7 193.0 Vegetables 0.012 (lb ai/ 1000 ft2) 1 0.012 3070.2 648148.1 3055.7 Vegetables/ Ornamentals 0.023 (lb ai/ 1000 ft2) 1 0.023 1601.8 338164.3 1594.3 Vegetables 0.047 (lb ai/ 1000 ft2) 1 0.047 783.9 165484.6 780.2 Average Study Use Rate 0.083 (lb ai/ 1000 ft2) 1 0.083 443.9 93708.2 441.8 Fire Ant 0.0075 (lb ai/ gal spray) 5 0.0375 982.5 207407.4 977.8 TABLE 11 CARBARYL NONCANCER MOEs ATTRIBUTABLE TO COMBINED SHORT TERM HOMEOWNER HANDLER DERMAL AND INHALATION EXPOSURES SCEN. SCEN. DESCRIPTOR CROP TYPE OR TARGET EXPOSURE FACTORS DERMAL MOEs INHALATION MOEs COMBINED MOEs APPL. RATE (lb ai/ unit) BASIS FOR RATE (defines unit treated) TREATED UNITS ACTIVE USED (lb ai/ event)

51 5 Trees/ Ornamentals: Low Pressure Handwand (MRID 445185 01) Ornamental 0.023 (lb ai/ 1000 ft2) 1 0.176 1087.0 468227.4 1084.4 Pome Fruit 0.07 (lb ai/ 1000 ft2) 1 0.07 357.1 153846.2 356.3 Nuts/ Stone Fruit 0.12 (lb ai/ 1000 ft2) 1 0.12 208.3 89743.6 207.9 Citrus 0.176 (lb ai/ 1000 ft2) 1 0.023 142.0 61188.8 141.7 Average Study Use Rate 0.0047 (lb ai/ gal, 17g ai/ 4 min at 2GPM) 5 0.024 1063.8 458265.1 1061.4 6 Trees/ Ornamentals: Hose End Sprayer (MRID 445185 01) Ornamental 0.023 (lb ai/ 1000 ft2) 1 0.176 1560.8 1217391.3 1558.8 Pome Fruit 0.07 (lb ai/ 1000 ft2) 1 0.07 512.8 400000.0 512.2 Nuts/ Stone Fruit 0.12 (lb ai/ 1000 ft2) 1 0.12 299.1 233333.3 298.8 Citrus 0.176 (lb ai/ 1000 ft2) 1 0.023 204.0 159090.9 203.7 Average Study Use Rate 0.005 (lb ai/ gal spray) 100 0.5 71.8 56000.0 71.7 7 Garden: Backpack Sprayer (PHED) General Use (2% soln) 0.02 (lb ai/ gal spray applied) 5 0.1 2745.1 23333.3 2456.1 Perimeter Nuisance Pest 0.19 (lb ai/ 1000 ft2) 1 0.19 1444.8 12280.7 1292.7 Vegetables 0.012 (lb ai/ 1000 ft2) 1 0.012 22875.8 194444.4 20467.8 Vegetables/ Ornamentals 0.023 (lb ai/ 1000 ft2) 1 0.023 11935.2 101449.3 10678.9 Vegetables 0.047 (lb ai/ 1000 ft2) 1 0.047 5840.6 49645.4 5225.8 Average Study Use Rate 0.083 (lb ai/ 1000 ft2) 1 0.083 3307.3 28112.5 2959.2 Fire Ant 0.0075 (lb ai/ gal spray) 5 0.0375 7320.3 62222.2 6549.7 8 Lawn Care: Hose End Sprayer (MRID 449722 01/ ORETF OMA 004) Lawn (broadcast) 0.25 (lb ai/ 1000 ft2) 20 5 25.5 875.0 24.7 Lawn (spot) 0.25 (lb ai/ 1000 ft2) 1 0.25 509.1 17500.0 494.7 9 Dusting Dog (MRID 444399 01) Average Study Use Rate 0.0026 (lb ai/ dog) 1 0.0026 163.2 1076.9 141.7 Dog (10% & ½ of 2 lb) 0.1 (lb ai/ dog) 1 0.1 4.2 28.0 3.7 Dog (5% & ½ of 2 lb) 0.05 (lb ai/ dog) 1 0.05 8.5 56.0 7.4 10 Dogs: Liquid Application Dog (0.5% & ½ of 6 oz) 0.001 (lb ai/ dog) 1 0.001 14000000.0 No Data No Data 11 Granular & Baits Lawn Care: Belly Grinder Lawn (spot) 0.21 (lb ai/ 1000 ft2) 1 0.21 60.6 5376.3 59.9 Lawn (spot) 0.1 (lb ai/ 1000 ft2) 1 0.1 127.3 11290.3 125.9 12 Granular & Baits Lawn Care: Push Type Spreader (MRID 449722 01/ ORETF OMA 003) Lawn (broadcast) 0.21 (lb ai/ 1000 ft2) 20 4.2 490.2 18315.0 477.4 Lawn (broadcast) 0.1 (lb ai/ 1000 ft2) 20 2 1029.4 38461.5 1002.6 13 Granulars & Baits By Hand Ornamentals and Gardens 0.21 (lb ai/ 1000 ft2) 1 0.21 15.5 713.8 15.2 14 Aerosol Various 0.005 (0.5 % ai in soln./ 1 pt can) 16 0.08 79.5 364.6 65.3 15 Collar Dog 0.013 (16 % ai per 1.3 oz collar) 1 0.013 10769230.8 No Data No Data TABLE 11 CARBARYL NONCANCER MOEs ATTRIBUTABLE TO COMBINED SHORT TERM HOMEOWNER HANDLER DERMAL AND INHALATION EXPOSURES SCEN. SCEN. DESCRIPTOR CROP TYPE OR TARGET EXPOSURE FACTORS DERMAL MOEs INHALATION MOEs COMBINED MOEs APPL. RATE (lb ai/ unit) BASIS FOR RATE (defines unit treated) TREATED UNITS ACTIVE USED (lb ai/ event)

52 16 Sprinkler Can (Source: Scenario 6) Ornamentals (2% Soln) 0.02 (2% soln used ad libitum) 5 0.1 359.0 280000.0 358.5 17 Ornamental Paint On Ornamentals (2% Soln) 0.02 (2% soln used ad libitum) 1 0.02 304.3 12323.9 297.0 <IP_ADDRESS> Residential Handler Cancer Risks Cancer risks were calculated by comparing the Lifetime Average Daily Dose (LADD) to the Q1* (8.75 x 10 4 (mg/ kg/ day) 1 ). The LADD was calculated using the equation below.

LADD = ADD xTreatment frequency x Working duration 365 days/ year Lifetime Where:

LADD = Lifetime Average Daily Dose or the amount as absorbed dose received from exposure to a pesticide in a given scenario amortized over a lifetime (mg pesticide active ingredient/ kg body weight/ day); ADD = Average Daily Dose or the amount as absorbed dose received from exposure to a pesticide in a given scenario on a daily basis (mg pesticide active ingredient/ kg body weight/ day) [Note: Represents inhalation and dermal exposure contributions, dermal component has been calculated with a 12.7 % absorption factor defined in a rat study.]; Treatment Frequency = The annual frequency of an application by an individual (days/ year); Working Duration = The amount of a lifetime that an individual spends engaged in a career involving pesticide exposure (years); Lifetime = The average life expectancy of an individual (years).

Cancer risk was then calculated using the following equation:

Risk = LADD x Q1*

Where:

Risk = Probability of excess cancer cases over a lifetime (unitless); Lifetime Average Daily Dose = The amount as absorbed dose received from exposure to a pesticide in a given scenario over a lifetime (mg pesticide active ingredient/ kg body weight/ day, also referred to as LADD); and Q1* = Quantitative dose response factor used for linear, low dose response cancer risk calculations (mg/ kg/ day) 1 . 53 Table 12 presents the quantitative risks associated with each scenario considered in the assessment. For all but one scenario (i. e., treating dogs with ½ bottle of 10 percent dust  risk is 1.09x10 6 ), cancer risks are less than 1x10 6 (most are in the 10 8 or 10 10 range) when a single application per year is evaluated. The risk associated with dusting a dog should also be taken in context of the uncertainties associated with cancer risk assessment. In effect, this value is 1x10 6 . This table also includes the allowable number of days exposure per year. There are 5 scenarios where 5 days or less of exposure per year is allowable. These results should be considered in conjunction with the use and usage information supplied by the Aventis Crop Science that indicates the 50 th percentile annual frequency of use is between 1 and 2 uses per year and that 5 uses per year is at the 84 th percentile. As with the noncancer risks, the use of dusts in gardens and for pet grooming along with some liquid sprays on ornamentals appear to be the most problematic scenarios. [Note: The scenario where risks are still of concern (i. e., >1x10 6 ) is highlighted in the table.] Cancer risks appear to be less of concern compared to noncancer risks for all corresponding scenarios.

TABLE 12: CARBARYL CANCER RISKS ATTRIBUTABLE TO COMBINED HOMEOWNER HANDLER DERMAL AND INHALATION EXPOSURES SCEN. SCEN. DESCRIPTOR CROP TYPE OR TARGET EXPOSURE FACTORS CANCER RISK ALLOWED DAYS/ YR APPL. RATE (lb ai/ unit) BASIS FOR RATE (defines unit treated) TREATED UNITS ACTIVE USED (lb ai/ event) 1 Garden: Ready to Use Trigger Sprayer (MRID 444598 01) Vegetables/ Ornamentals 0.003 32 oz bottle 0.126 % (769 977) 0.25 0.00075 1.27e 10 >365 Vegetables/ Ornamentals 0.003 32 oz bottle 0.126 % (769 977) 0.5 0.0015 2.54e 10 >365 Vegetables/ Ornamentals 0.003 32 oz bottle 0.126 % (769 977) 1 0.003 5.08e 10 >365 Average Study Use Rate 0.012 (lb ai/ 1000 ft2) 1 0.012 2.03e 09 >365 2 Garden/ Ornamental Dust (MRID 444598 01) Vegetables/ Ornamentals 0.4 4 lb bottle 10% (239 1513) 0.25 0.1 4.81e 08 21 Vegetables/ Ornamentals 0.4 4 lb bottle 10% (239 1513) 0.5 0.2 9.62e 08 10 Vegetables/ Ornamentals 0.4 4 lb bottle 10% (239 1513) 1 0.4 1.92e 07 5 Average Study Use Rate 0.079 (lb ai/ 1000 ft2) 1 0.079 3.80e 08 26 3 Garden: Hose End (MRID 444598 01) General Use (2% soln) 0.02 (lb ai/ gal spray applied) 100 2 2.11e 07 5 Perimeter Nuisance Pest 0.19 (lb ai/ 1000 ft2) 1 0.19 2.01e 08 50 Vegetables 0.012 (lb ai/ 1000 ft2) 1 0.012 1.27e 09 >365 Vegetables/ Ornamentals 0.023 (lb ai/ 1000 ft2) 1 0.023 2.43e 09 >365 Vegetables 0.047 (lb ai/ 1000 ft2) 1 0.047 4.97e 09 201 Average Study Use Rate 0.26 (lb ai/ 1000 ft2) 1 0.26 2.75e 08 36 Fire Ant 0.0075 (lb ai/ gal spray) 100 0.75 7.93e 08 13 4 Garden: Low Pressure Handwand (MRID 444598 01) General Use (2% soln) 0.02 (lb ai/ gal spray applied) 5 0.1 1.18e 08 85 Perimeter Nuisance Pest 0.19 (lb ai/ 1000 ft2) 1 0.19 2.25e 08 45 Vegetables 0.012 (lb ai/ 1000 ft2) 1 0.012 1.42e 09 >365 Vegetables/ Ornamentals 0.023 (lb ai/ 1000 ft2) 1 0.023 2.72e 09 >365 Vegetables 0.047 (lb ai/ 1000 ft2) 1 0.047 5.56e 09 180 Average Study Use Rate 0.083 (lb ai/ 1000 ft2) 1 0.083 9.82e 09 102 Fire Ant 0.0075 (lb ai/ gal spray) 5 0.0375 4.44e 09 225 TABLE 12: CARBARYL CANCER RISKS ATTRIBUTABLE TO COMBINED HOMEOWNER HANDLER DERMAL AND INHALATION EXPOSURES SCEN. SCEN. DESCRIPTOR CROP TYPE OR TARGET EXPOSURE FACTORS CANCER RISK ALLOWED DAYS/ YR APPL. RATE (lb ai/ unit) BASIS FOR RATE (defines unit treated) TREATED UNITS ACTIVE USED (lb ai/ event)

54 5 Trees/ Ornamentals: Low Pressure Handwand (MRID 445185 01) Ornamental 0.023 (lb ai/ 1000 ft2) 1 0.176 4.01e 09 250 Pome Fruit 0.07 (lb ai/ 1000 ft2) 1 0.07 1.22e 08 82 Nuts/ Stone Fruit 0.12 (lb ai/ 1000 ft2) 1 0.12 2.09e 08 48 Citrus 0.176 (lb ai/ 1000 ft2) 1 0.023 3.06e 08 33 Average Study Use Rate 0.0047 (lb ai/ gal, 17g ai/ 4 min at 2GPM) 5 0.47 4.09e 09 244 6 Trees/ Ornamentals: Hose End Sprayer (MRID 445185 01) Ornamental 0.023 (lb ai/ 1000 ft2) 1 0.176 2.79e 09 359 Pome Fruit 0.07 (lb ai/ 1000 ft2) 1 0.07 8.49e 09 118 Nuts/ Stone Fruit 0.12 (lb ai/ 1000 ft2) 1 0.12 1.45e 08 69 Citrus 0.176 (lb ai/ 1000 ft2) 1 0.023 2.13e 08 47 Average Study Use Rate 0.005 (lb ai/ gal spray) 100 0.025 6.06e 08 16 7 Garden: Backpack Sprayer (PHED) General Use (2% soln) 0.02 (lb ai/ gal spray applied) 5 0.1 1.66e 09 >365 Perimeter Nuisance Pest 0.19 (lb ai/ 1000 ft2) 1 0.19 3.15e 09 317 Vegetables 0.012 (lb ai/ 1000 ft2) 1 0.012 1.99e 10 >365 Vegetables/ Ornamentals 0.023 (lb ai/ 1000 ft2) 1 0.023 3.81e 10 >365 Vegetables 0.047 (lb ai/ 1000 ft2) 1 0.047 7.79e 10 >365 Average Study Use Rate 0.083 (lb ai/ 1000 ft2) 1 0.083 1.38e 09 >365 Fire Ant 0.0075 (lb ai/ gal spray) 5 0.0375 6.22e 10 >365 8 Lawn Care: Hose End Sprayer (MRID 449722 01/ ORETF OMA 004) Lawn (broadcast) 0.25 (lb ai/ 1000 ft2) 20 5 1.73e 07 6 Lawn (spot) 0.25 (lb ai/ 1000 ft2) 1 0.25 8.64e 09 116 9 Dusting Dog (MRID 444399 01) Average Study Use Rate 0.0026 (lb ai/ dog) 1 0.0026 2.82e 08 35 Dog (10% & ½ of 2 lb) 0.1 (lb ai/ dog) 1 0.1 1.09e 06 1 Dog (5% & ½ of 2 lb) 0.05 (lb ai/ dog) 1 0.05 5.43e 07 2 10 Dogs: Liquid Application Dog (0.5% & ½ of 6 oz) 0.001 (lb ai/ dog) 1 0.001 3.11e 13 >365 11 Granular & Baits Lawn Care: Belly Grinder Lawn (spot) 0.21 (lb ai/ 1000 ft2) 1 0.21 7.21e 08 14 Lawn (spot) 0.1 (lb ai/ 1000 ft2) 1 0.1 3.43e 08 29 12 Granular & Baits Lawn Care: Push Type Spreader (MRID 449722 01/ ORETF OMA 003) Lawn (broadcast) 0.21 (lb ai/ 1000 ft2) 20 4.2 8.97e 09 112 Lawn (broadcast) 0.1 (lb ai/ 1000 ft2) 20 2 4.27e 09 234 13 Granulars & Baits By Hand Ornamentals and Gardens 0.21 (lb ai/ 1000 ft2) 1 0.21 2.83e 07 4 14 Aerosol Various 0.005 (0.5 % ai in soln./ 1 pt can) 16 0.08 5.94e 08 17 15 Collar Dog 0.013 (16 % ai per 1.3 oz collar) 1 0.013 4.04e 13 >365 16 Sprinkler Can (Source: Scenario 6) Ornamentals (2% Soln) 0.02 (2% soln used ad libitum) 5 0.1 1.21e 08 82 17 Ornamental Paint On Ornamentals (2% Soln) 0.02 (2% soln used ad libitum) 1 0.02 1.44e 08 69 55 4.4.3 Residential Postapplication Risk Assessment Carbaryl uses are extremely varied and include home gardens, ornamentals, turf (golf courses and lawns) and companion animals (e. g., on dogs and cats). Carbaryl also has more limited uses that were considered including as a mosquito adulticide in residential areas and for Ghost/ Mud shrimp control in Washington. As a result, a wide array of individuals of varying ages can potentially be exposed when they do activities in areas that have been previously treated or have contact with treated companion animals. The residential postapplication risk assessment addresses these types of exposures.

The risks from exposure to carbaryl residues postapplication were determined for the following populations:

1) Residential (homeowner) Adults: The following postapplication scenarios were assessed: residential turf (lawncare), residential turf (after mosquito control), swimming/ beach activity (oyster bed treatments), golfing, home garden exposure to deciduous trees and home garden exposure to fruiting vegetables. Within each scenario, ranges of exposure were evaluated for different application rates, duration of exposure, and postapplication activities (e. g., weeding, harvesting).

2) Toddlers (3 year olds): Toddlers were selected as a representative population for turf and companion animal assessments. Exposures from turf were evaluated separately for lawncare uses and after mosquito control. Beach activity (oyster bed treatments) was also evaluated. Separate risk assessments were considered individually and as a total exposure for turf  dermal exposure and hand to mouth, object to mouth and soil ingestion. For pet uses and the beach play assessments, dermal and hand to mouth exposures were considered individually and as a total exposure. A separate assessment was done for toddlers who could potentially ingest carbaryl granules. [Note: Values for this population were used in the aggregate risk calculations for children (1 to 6 years old).]

3) Youth aged children (ages 10 to 12): children of this age could help with garden maintenance (deciduous trees and fruiting vegetables) and therefore were considered for activities related to fruiting vegetables and fruit trees.

Data and Assumptions A series of assumptions and exposure factors served as the basis for completing the residential handler risk assessments, as described below. The assumptions and factors used in the risk calculations are consistent with current Agency policy for completing residential exposure assessments (i. e., SOPs For Residential Exposure Assessment and related documents).

° Several carbaryl specific studies were used in the development of this assessment including a turf transferable residue (TTR) study conducted in California, Georgia, and Pennsylvania at 8.17 lb ai/ acre (MRID 451143 01). This study was conducted using the standard ORETF protocol. The Georgia data were used for the assessment (all were similar). Residue transferability observed in this data was 1.20 percent. The Agricultural Reentry Task Force (ARTF) conducted several dislodgeable foliar residue (DFR) studies with carbaryl. The olive pruning (MRID 56 451751 02) and cabbage weeding (MRID 451917 01) studies were used in the home garden risk assessments. Aventis Crop Science is a member of the ARTF so there are no data compensation issues associated with the use of these data. All of these carbaryl specific studies should be considered high quality for risk assessment purposes.

° Two other studies completed by the Washington State Department of Ecology were used for completing the risk assessment for the oyster bed use. These studies provided water and sediment concentration data in Willapa Bay where these applications occur.

° Exposure frequency values used in cancer risk assessments for adults are the same as those used for residential handlers (1 time per year). However, the Agency does believe that there are higher frequency golfers (i. e., average golfers over all ages play 18 rounds year) based on a 1992 report (Golf Course Operations, Cost of Doing Business/ Profitability by the Center For Golf Course Management). The number of exposure days per year has also been calculated for all postapplication exposure scenarios.

° Several models and published data sources were also used to develop the risk assessment. These include papers related to: deposition from mosquito control by Dukes et al from Florida A& M University and transference of residues from treated pets by Boone et al from Mississippi State University. The Agency's Standard Operating Procedures For Residential Exposure Assessment were the primary guidance used for this assessment. Several other models and guidance documents were also used including the Agency's SWIMODEL (for swimmers in Willapa Bay after oyster bed treatments); AgDrift V2.0 (for risks from mosquito control), and the Risk Assessment Guidance For Superfund or RAGS (for dermal exposures during beach play and oyster harvest). Specific information from the mosquito control label and historical information for oyster bed applications were also used to complete the assessments (e. g., droplet spectra requirements to predict deposition from aerial treatments during mosquito control).

° The Agency calculates total exposures to individual chemicals when it is likely that behaviors could occur simultaneously that would lead to the overall dose for the exposed population of concern. The Agency has added together risk values (i. e., MOEs) for different kinds of exposures within the turf (dermal, hand to mouth, object to mouth, and soil ingestion) and pet scenarios (dermal and hand to mouth). These represent the standard set of exposures that are typically added together when chemicals are used on turf or on pets because it is logical they can co occur.

° Exposures to children playing on treated turf as well as adults on turf (lawncare and golfing) have been addressed using the latest Agency approaches for this scenario including: ° 5 percent of the application rate has been used to calculate the 0 day residue levels used for defining risks from hand to mouth behaviors, measured TTR values are not used because of differences in transferability versus what would be expected during hand tomouth behaviors; 57 ° 20 percent of the application rate has been used to calculate the 0 day residue levels used for defining risks from object to mouth behaviors, measured TTR values are not used because of differences in transferability versus what would be expected during hand tomouth behaviors, a higher percent transfer has been used for object to mouth behaviors because it involves a teething action believed to be more analogous to DFR/ leaf wash sample collection where 20 percent is also used; ° the measured TTR levels quantified in MRID 451143 01 have been used to complete the dermal exposure calculations as the 0 day transferability was > 1 percent of the application rate for the short and intermediate term data sources, studies where transferability is less than 1 percent are not used for risk assessment purposes because the transfer coefficients used by the Agency for defining exposures are based on Jazzercize studies in which TTR values were measured by techniques where transferability is generally in the 1 to 5 percent range other than the ORETF roller method where transferability tends to be lower; ° short and intermediate term exposures have been calculated because play and mouthing behaviors are assumed to routinely occur daily and for extended periods such as over 30 days, carbaryl residues are also expected to be present based on residue dissipation data (i. e., slow dissipation rate); ° in cases where 0 day residues have been calculated based on application rates (i. e., hand object to mouth residues and for soil dissipation), dissipation over time measured in the TTR study (i. e., slope of decay curve) has been used to predict TTR and soil levels over time, carbaryl residues were detectable even at 14 days after application (i. e., final sampling interval) at all sites in the TTR studies used in this assessment, at 14 days average residues at the Georgia and Pennsylvania study sites were still orders of magnitude above the quantitation limit, this indicates that predicted residue levels for extended durations should be considered appropriate based on the empirical data (e. g., critical for consideration of intermediate term exposures); ° the transfer coefficients used, except golfing, are those presented at the 1999 Agency presentation before the FIFRA Science Advisory Panel that have been adopted in routine practice by the Agency; ° transfer coefficients have been adjusted for differences between short and intermediateterm exposures; ° adult golfers have been assessed using a transfer coefficient of 500 cm 2 /hour [Note: The Agency is currently developing a policy on golfer exposures and has used this value in other assessments]; ° 3 year old toddlers are expected to weigh 15 kg; ° hand to mouth exposures are based on a frequency of 20 events/ hour and a surface area per event of 20 cm 2 representing the palmar surfaces of three fingers; ° saliva extraction efficiency is 50 percent meaning that every time the hand goes in the mouth approximately ½ of the residues on the hand are removed; ° object to mouth exposures are based on a 25 cm 2 surface area; 58 ° exposure durations are expected to be 2 hours based on information in the Agency's Exposure Factors Handbook except for golfers where the exposure duration for an 18 hole round of golf is 4 hours based on a 1992 report (Golf Course Operations, Cost of Doing Business/ Profitability by the Center For Golf Course Management); ° soil residues are contained in the top centimeter and soil density is 0.67 mL/ gram; ° dermal, hand and object to mouth, and soil ingestion are added together to represent an overall risk from exposure to turf while granular ingestion is considered to be a much more episodic behavior and is considered separately by the Agency; and ° children of various ages down to the very young (e. g., 4 or 5 years old) are currently playing golf, the Agency recognizes that age may impact exposures because of changes in behavior and skin surface area to body weight ratios but has not yet developed a quantitative approach for calculating their risks.

° Exposures to children and adults working in home gardens have been addressed using the latest Agency approaches for this scenario including: ° youth aged children are considered along with adults; ° 12 year old youth are expected to weigh 39.1 kg; ° exposure durations are expected to be 40 minutes; ° Pre Harvest Intervals (PHIs) are less than 7 days for most crops with some as long as 28 days; ° transfer coefficients for youth were calculated by adjusting the appropriate adult transfer coefficients by a 50% factor as has been done by the Agency since the inception of the SOPs For Residential Exposure Assessment; ° the updated transfer coefficients specified in Agency policy 003 described above in the occupational risk assessment have been used rather than those currently specified in the SOPs because they represent more refined estimates of exposure for the fruiting vegetable and deciduous tree crop groups, these crop groups have been used in the SOPs to represent home garden exposures; ° the combination of adjusting transfer coefficients for youth aged children and using appropriate body weights for the age group results in dose levels that are slightly lower than that of adults in the same activity (the TC reduction and body weight reduction is essentially a 1: 1 ratio); and ° the DFR data used for the assessments are the same as those used in the occupational risk assessment for the selected crop groups.

° Exposures to children after contact with treated pets have been addressed using the latest Agency approaches for this scenario including: ° only toddlers are considered because their exposures are thought to be highest (i. e., they are considered the highest exposed population by the Agency); 59 ° an equilibrium approach based on a single child "hug" of the treated animal is used to assess dermal exposure as described in the 1999 Agency SAP Overview document (i. e., the skin loads after a single contact with the treated animal and additional contacts don't proportionally add exposures), the surface area of the dermal hug is based on a toddler skin surface area and typical clothing; ° residue dissipation is 5 percent per day for the shampoo and dust products (based on data from J. Chambers at Mississippi State University on other pet use products); ° the transferability of residues from fur is 20 percent; ° the active lifetime of a collar is expected to be 120 days based on label statements which was used by the Agency, a daily emission term from the collar of 0.000290 mg/ cm 2 /gram ai/ day is also based on measured data from Mississippi State University for a pet collar; ° risks are based on an even loading of residues across the entire surface of a 30 lb dog which has been chosen as a representative animal, the animal surface area was calculated using (12.3* Body Weight (g) 0.65 ) from the Agency's 1993 Wildlife Exposure Factors Handbook (i. e., dog surface area of 5986 cm 2 ); ° the daily frequency of hand to mouth contact with dogs is 40 events per day, in each event, the palmar surface of the hands (i. e., 20cm 2 /event) is placed in the mouth of the child contributing to nondietary ingestion exposure; and ° the Agency is currently in the process of considering revisions in its methodologies for completing risk assessments for pet products, some of the key inputs that are potentially subject to modification include the amount of residues which are transferable from pet fur, defining the number of hand to mouth events, and evaluating the emission term for collars.

° There are many likely studies focused on carbaryl in the published literature or available from various governmental Agencies because it is so widely used. For example, the Agency's Office of Research and Development along with other Agencies have funded a project entitled Pesticide Exposure in Children Living in Agricultural Areas along the United States Mexico Border Yuma County, Arizona. Preliminary results of this study indicate that carbaryl residues were identified in the dust of 20 percent of the 152 houses sampled and in approximately 24 percent in 25 samples collected in 6 schools in the same region. At this point, the Agency has not identified any data from the literature or other sources that would alter the conclusions of this risk assessment. As more data become available, the Agency will consider the information in efforts to refine the assessment (i. e., use additional information to alter numeric risk estimates or to characterize existing estimates if warranted). With regard to this specific example, current Agency policy is not to use house dust estimates to calculate risks because of a lack of an appropriate exposure model. Also, in a 1995 study conducted by the Centers For Disease Control (Hill et al) entitled Pesticide Residues In Urine Of Adults Living In The United States: Reference Range Concentrations, 1000 adults were monitored via urine collection. One of the analytes measured in that study (1 naphthol) is a potential metabolite of carbaryl as well as of naphthalene and napropamide. This metabolite was identified in 86 percent of the 1000 adults monitored where the mean value was 17 ppb and the 99 th percentile was 290 ppb. These values were not used quantitatively in the risk assessment for carbaryl because of the uncertainties associated with them such as the exact contribution of each possible compound to the overall 60 levels and no linked exposure information. The investigators also reported results for (2 naphthol) which is also a metabolite of naphthalene and indicated a common source of exposure because 1 naphthol and 2 naphthol levels were similar based on a Pearson correlation of 0.64 (P= 0.0001). The mean for 2 naphthol is 7.2 ppb and the 99 th percentile was 54 ppb. The Agency instead considers them a qualitative indicator that exposures in the general population are likely to occur.

° Aventis Crop Science has completed and is in the process of submitting to the Agency a biomonitoring study of individuals in residences following the application by a member of the household to the lawn and either the vegetable garden or ornamental flowers. A biomonitoring study of field workers during harvesting and hand thinning operations in apples and cherries will also be submitted to the Agency. Based on personal communication with Aventis Crop Science scientists, preliminary results from the residential biomonitoring study indicate that the highest percentiles of the distribution of the younger children in the homes were similar to those predicted in the Agency's turf risk assessment for toddlers that are intended to represent the higher percentiles of the exposure distribution. A more detailed analysis will be completed upon submission.

° Aventis Crop Science is also a member of the Residential Exposure Joint Venture which is a group of companies conducting a survey of homeowners to ascertain how consumer pesticide products are used (e. g., rate, frequency, pests, etc.). Also, based on discussions with Aventis Crop Science, an analysis of these data is expected to be submitted which could be used to refine the exposure estimates in this assessment because the amounts of carbaryl used per homeowner application could be refined. Preliminary discussions concerning this survey also indicate Agency estimates are in the range of those observed in the survey.

<IP_ADDRESS> Residential Postapplication Exposure and Noncancer Risks Two different types of noncancer risk calculations were required based on expected exposure durations, i. e., short term ( 30 days) and intermediate term (30 days up to several months). Intermediate term risks were calculated in a postapplication situation, when they were not for residential handlers, because residue dissipation data demonstrated that carbaryl residues persist over that time and it is clear that the behaviors considered as the basis for this assessment can occur routinely over extended periods of time thus creating a potential window for exposures (e. g., children playing outside on the grass is expected to be a routine activity). Noncancer risks were calculated using the MOE approach, as described under Section 4.4.2. The toxicological endpoint of concern and target MOE for short term and intermediate term dermal exposures is the same as that used for the short term dermal exposure for residential handlers (i. e., NOAEL of 20 mg/ kg from the 21 day dermal toxicity study in the rat and a target MOE of 100). The endpoints of concern and target MOE for short term and intermediate term nondietary ingestion exposure were defined in the rat developmental neurotoxicity study and subchronic neurotoxicity studies, respectively (i. e., NOAEL of 1 mg/ kg/ day defined in both studies with a target MOE of 100).

Several different types of calculations were used in this assessment to reflect the varying age 61 groups, behaviors, data, and activities that were considered. In essence, all can be summarized by saying that a source of some sort (e. g., DFR on leaves) comes in contact with a person as they are doing an activity (e. g., harvesting garden plants). Exposures were then calculated by multiplying the source concentration by some factor (e. g., transfer coefficient for fruit harvesting) and the duration. All of the calculations are explained in detail in the Occupational and Residential Exposure Chapter (281418). Two of the key algorithms are presented below for informational purposes. These represent the predominant types of exposures considered in the postapplication assessment (i. e., dermal and hand tomouth

Dermal exposures were calculated by considering the potential sources of exposure in the environment, which represent the DFRs on garden plants, TTRs on lawns, and transferable residues on treated pets using the following equation. It should also be noted that there are distinct transfer coefficients for different activities (e. g., fruit harvest versus lawncare).

DE( t) (mg/ day) = (TR( t) (µg/ cm 2 ) x TC (cm 2 /hr) x Hr/ Day)/ 1000 (µg/ mg)

Where:

DE( t) = Daily exposure or amount deposited on the surface of the skin at time (t) attributable for activity in a previously treated area, also referred to as potential dose (mg ai/ day); TR( t) = Transferable residues that can either be dislodgeable foliar or turf transferable residue at time (t) where the longest duration is dictated by the decay time observed in the studies (µg/ cm 2 ); TC = Transfer Coefficient (cm 2 /hour); and Hr/ day = Exposure duration meant to represent a typical workday (hours).

[Note: For pets, the TC and Hr/ day terms are replaced with a onetime "hug" scenario.]

Likewise, nondietary ingestion from hand to mouth behaviors also consider the environmental concentrations and the mouthing behaviors of children. The following equation describes how these exposures have been calculated.

Where: D = dose from hand to mouth activity (mg/ day); TR = Transferable Residue where dissipation is based on TTR study and the 0 day value is based on the 5% initial transferability factor (µg/ cm 2 ); SE = saliva extraction factor (%); SA = surface area of the hands (cm 2 ); Freq = frequency of hand to mouth events (events/ hour); and Hr = exposure duration (hours). 6 Maximum rates of 4 to 8 lb ai/ acre are specified for different pests. There is one carbaryl label with a turf application rate of 11 lb ai/ acre; however, based on the information from the registrant at the SMART meeting and the TTR study (MRID 45334301), the maximum rate is more likely to be 8 lbs ai/ acre. In addition, risks exceed HED's level of concern at 8 lbs ai/ acre.

62 The (TR( t)) input may represent levels on a single day after application in the case of short term risk calculations. For intermediate term calculations, 30 day average concentrations were calculated based on the applicability of the toxicology data (i. e., intermediate term endpoint is applied to exposures >30 days).

Adult Short term MOEs only for lawncare (i. e., heavy yardwork) exceed the Agency's level of concern on the day of application (i. e., 43 to 88). For this activity, it takes 1 and 5 days, respectively at the 4 and 8 lb ai/ acre application rates, 6 for residues to dissipate to a point where short term MOEs are $ 100. In all other scenarios considered, short term MOEs are $ 100 on the day of application. These other scenarios include vegetable gardening, golfing, tending fruit trees. More localized exposures that occur after mosquito control or from exposures associated with oyster bed treatments are also included. Intermediate term MOEs were calculated using 30 day average exposures and the dissipation rate for carbaryl. In all cases, intermediate term MOEs are $ 100. Table 13 presents the postapplication MOE values calculated for adults after lawn and home garden applications of carbaryl.

Table 13: Summary of Carbaryl Noncancer Postapplication Residential MOEs For Adults Scenario Descriptor Results Short term MOE on Day 0 Days Short term MOE UF Intermediateterm MOE Residential Turf (Lawncare) Max Rate at 4 lb ai/ A 88 1 842 Max Rate at 8 lb ai/ A 43 5 412 Aerial  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 3700 231268 0 35463 2216454 Ground  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 7031 439409 0 67380 4211262 Golfing Max Rate at 4 lb ai/ A 1274 0 12297 Max Rate at 8 lb ai/ A 624 0 6021 Aerial  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 53654 3353387 0 517764 32360224 Ground  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 101943 6371435 0 983751 61484426 Table 13: Summary of Carbaryl Noncancer Postapplication Residential MOEs For Adults Scenario Descriptor Results Short term MOE on Day 0 Days Short term MOE UF Intermediateterm MOE 63 Home Garden (Deciduous Tree) Very Low Exposure (propping) 17373 0 53139 Low Exposure (irrigation, scout, weed) 1737 0 5314 High Exposure (harvest, prune, train, tie, thin) 579 0 1771 Home Garden (Fruiting Vegetable) Low Exposure (irrigation, scout, thin, weed) 1758 0 9468 Medium Exposure (irrigation, scout) 1256 0 6763 High Exposure (harvest, prune, stake, tie) 879 0 4734 Oyster Beds Oyster Harvest 967137 0 2680745 Swimming 293651 0 No Data Youth aged children (10 to 12 years old) were only considered in the home garden scenarios per Agency guidance. Short term MOEs for these children were similar to those calculated for adults in that they were $ 100 for all of the gardening scenarios considered. Intermediate term MOEs were calculated using 30 day average exposures and the dissipation rate for carbaryl. In all cases, intermediate term MOEs are $ 100. Table 14 below summarizes the postapplication MOE values calculated for youth home garden applications of carbaryl.

Table 14: Summary of Carbaryl Noncancer Postapplication Residential MOEs For Youth Aged Children Scenario Descriptor Results Short term MOE on Day 0 Days Short term MOE UF Intermediateterm MOE Home Garden (Deciduous Tree) Very Low Exposure (propping) 19408 0 59364 Low Exposure (irrigation, scout, weed) 1941 0 5936 High Exposure (harvest, prune, train, tie, thin) 647 0 1979 Table 14: Summary of Carbaryl Noncancer Postapplication Residential MOEs For Youth Aged Children Scenario Descriptor Results Short term MOE on Day 0 Days Short term MOE UF Intermediateterm MOE 64 Home Garden (Fruiting Vegetable) Low Exposure (irrigation, scout, thin, weed) 1964 0 10577 Medium Exposure (irrigation, scout) 1403 0 7555 High Exposure (harvest, prune, stake, tie) 982 0 5289 Toddler (3 year old) exposures were considered for a variety of scenarios as described above including play on treated turf, play with treated pets, after mosquito control, and after oyster bed treatments. Ingestion of granules, which is considered a highly episodic event by the Agency is also described below. The results from all scenarios considered are presented below in Table 15.

Short term MOEs from exposure to treated turf (in products labeled for direct application to turf) were <100 on the day of application for both rates considered (i. e., 4 and 8 lb ai/ acre). In fact, shortterm MOEs from individual pathways were not $ 100 for any turf scenario considered on the day of application except for the soil ingestion component of the turf assessment which is a very minor contributor to overall exposures. As a reminder, dermal, hand to mouth, and object to mouth exposures pathways were considered along with soil ingestion. Total short term MOEs (all pathways) were $ 100 at the lower 4 lb ai/ acre application rate 14 days after application and 18 days at the higher 8 lb ai/ acre application rate. Dermal and hand to mouth exposures were the key contributors while soil ingestion was a minor contributor to the total MOE estimates. Intermediate term MOEs were calculated using 30 day average exposures and the dissipation rate for carbaryl. For both rates, intermediate term MOEs were <100. Exposures to toddlers were also considered after application of carbaryl as a mosquito adulticide. The risks are presented along with the turf use risks because the methods are similar except that mosquito control calculations also account for deposition from aerial and ground foggers. Regardless of how applications are made (i. e., by ground or air), both short term MOEs on the day of application and intermediate term MOEs were $ 100.

The assessments for pet uses considered dermal and nondietary ingestion exposures and also calculated total MOEs. Short term MOEs for pet uses were <100 even 30 days after application regardless of whether the formulation used was a dust, liquid or collar. This trend was observed for each separate exposure pathway as well as the total MOE estimates. Hand to mouth and dermal exposures are approximately equal contributors to the overall estimates for each product type. The results are similar for the intermediate term MOEs for each scenario. There is one pet use which is also considered to be a chronic exposure by the Agency. Pet collars are assumed to be worn all of the time so chronic exposure can potentially occur. The chronic MOE for pet collars mirrors the short and intermediate term results.

The assessments for beach play for toddlers after oyster bed treatment considered dermal and 65 nondietary ingestion exposures and also calculated total MOEs. Short term MOEs were >100 even if the highest monitored sediment concentration value from any study available to the Agency was used as the basis for the calculations. The intermediate term results were similar.

Table 15: Summary of Carbaryl Noncancer Postapplication Residential Aggregate MOEs For Toddlers Scenario Descriptor Results Short term MOE on Day 0 Days For Short term MOE UF Intermediateterm MOE Chronic MOE Pet Treatments Liquids 2.0 +30 4 NA Dusts 0. 02 +30 0.04 NA Collars 18 +30 18 43 Residential Turf (High Activity) Max Rate at 4 lb ai/ A 11 14 91 NA Max Rate at 8 lb ai/ A 5 18 45 NA Aerial  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 448 27983 0 3826 239095 NA Ground  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 851 53167 0 7269 454280 NA Oyster Beds Beach Play 29532 0 81859 NA Ingestion of carbaryl granules is also a potential source of exposure because children can eat them if they are found in treated lawns or gardens. This scenario is considered to be an episodic in nature. Therefore, acute dietary endpoints are always used. The concentration of carbaryl in granular products ranges generally from 2 to 10 percent. If this information is coupled with the body weight of a toddler (15 kg), the NOAEL of 1 mg/ kg/ day for short term assessments (which is also the same value used for the aPAD), and the uncertainty factor of 100 the amount of formulation that can be consumed at the uncertainty factor MOE level can be calculated. The Agency generally presents these results based on the number of carbaryl granules that can be ingested. However, the number of homeowner formulations is extensive and impossible to characterize in that much detail so a general weight estimate is presented. If a 2 percent formulation is ingested, 7.5 mg represents exposure at an MOE of 100 (i. e., 1.6 x 10 5 lb). If a 10 percent formulation is ingested, 1.5 mg represents exposure at an MOE of 100 (i. e., 3.3 x 10 6 lb). For illustrative purposes, if one considers a 2 percent formulation and the density of soil (0.67 mL/ gram, many granulars are clay based), only 0.005 mL of formulation would need to be ingested to have a risk concern (i. e., 7.5 mg * 1g/ 1000mg * 0.67 mL/ gram). Note that this volume is 66 orders of magnitude less than a teaspoon of granular formulation (i. e., 0.1% of a teaspoon where a tsp. = 5 mL).

<IP_ADDRESS> Residential Postapplication Exposure and Risks For Cancer Postapplication cancer risks were calculated for adults only considering the same scenarios. Risks were calculated using a frequency of one exposure per year for 50 years. Cancer risks were calculated using a linear low dose extrapolation approach in which a LADD is calculated and then compared with a Q1* (8.75 x 10 4 (mg/ kg/ day) 1 ), as described in Section <IP_ADDRESS>. The number of days of exposure per year under a ceiling limit of cancer risks equal to 1x10 6 was also calculated.

For all scenarios on turf, cancer risks are in the 10 8 range or less on the day of application when a single reentry event per year during lawncare activities is evaluated. For home gardening, golfing or from mosquito control, risks are slightly lower in the 10 9 to 10 12 range when a single reentry event per year is evaluated on the day of application. Table 16 below summarizes the postapplication risk values calculated for adults after applications of carbaryl. Risk managers should consider these values represent a single reentry day into a treated area over each year of a 50 year lifetime on the day of application and that the Agency lacks data to link the annual frequency of reentry activity to residential applications. As with the residential handler risks above, the Agency calculated the number of exposure days needed to reach a risk level of 1x10 6 for each scenario on the day of application, values range from 20 to over 365 days per year while most exceed 365 days per year.

Table 16: Summary of Carbaryl Postapplication Residential Cancer Risks For Adults Scenario Descriptor Results Risk on Day 0 Allowed Days/ Year Residential Turf (Lawncare) Max Rate at 4 lb ai/ A 2.5 x 10 8 40 Max Rate at 8 lb ai/ A 5.1 x 10 8 20 Aerial  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 9.5 x 10 12 to 5.9 x 10 10 >365 Ground  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 5.0 x 10 12 to 3.1 x 10 10 >365 Golfing Max Rate at 4 lb ai/ A 1.7 x 10 9 >365 Max Rate at 8 lb ai/ A 3.5 x 10 9 287 Aerial  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 6.5 x 10 13 to 4.1 x 10 11 >365 Ground  Mosquito Adulticide 0.016 to 1.0 lb ai/ A 3.4 x 10 13 to 2.1 x 10 11 >365 Table 16: Summary of Carbaryl Postapplication Residential Cancer Risks For Adults Scenario Descriptor Results Risk on Day 0 Allowed Days/ Year 67 Home Garden (Deciduous Tree) Very Low Exposure (propping) 2.5 x 10 10 >365 Low Exposure (irrigation, scout, weed) 2.5 x 10 9 >365 High Exposure (harvest, prune, train, tie, thin) 7.5 x 10 9 133 Home Garden (Fruiting Vegetable) Low Exposure (irrigation, scout, thin, weed) 2.5 x 10 9 >365 Medium Exposure (irrigation, scout) 3.5 x 10 9 289 High Exposure (harvest, prune, stake, tie) 4.9 x 10 9 202 Oyster Beds Oyster Harvest 4. 5 x 10 12 >365 Swimming 6.1 x 10 12 >365 4.4.4 Residential Risk Characterization Characterization of the residential risks is included below for both handlers and for postapplication exposures.

Residential Handlers: The residential handler assessment for carbaryl is complex in that calculations were completed for 52 different equipment and application rate scenarios. Unlike the occupational assessments, only short term exposures were considered for handlers because homeowner use patterns are not believed by the Agency to lead to intermediate term exposures because of their sporadic nature. Cancer risks were also calculated using a linear, low dose extrapolation model (i. e., Q1*) for typical residential users (1 event/ year). Cancer risks were also considered by calculating the number of days exposure that would be required per year to achieve a cancer risk of 1x10 6 to illustrate risk levels from another perspective. All totaled, when each type of calculation is considered, 108 different crop/ application method calculations were completed for residential handlers.

The data that were used in the in the carbaryl residential handler assessment represent the best data and approaches that are currently available. For most of the major use patterns, carbaryl specific data or data generated by the Outdoor Residential Exposure Task Force were used. These data generally are considered to be high quality by the Agency and the best source of information available for the scenarios where they were used. Carbaryl specific data were used to address the garden and 68 tree/ ornamental scenarios with several types of equipment and formulations including liquid trigger sprayers, dusts, and liquid sprays using low pressure handwand and hose end sprayers. Carbarylspecific data were also available for dusting dogs. The ORETF data for hose end sprayer applications to turf and granular applications to turf were also used to address those scenarios. In the remaining scenarios, the Pesticide Handlers Exposure Database (PHED) was used to develop the unit exposure values. The quality of the data included in PHED vary widely from scenarios that meet guideline requirements for studies to others where a limited number of poor quality datapoints are available. All data that have been used may not be of optimal quality but represent the best available data.

The inputs for application rate and other use/ usage information (e. g., area treated and frequency of use) used by the Agency were supported by the available carbaryl labels and information supplied by the Aventis Crop Science at the September 24, 1998 SMART Meeting. It is also very clear that because carbaryl is such as widely used chemical that it is likely every potential exposure scenario has not been captured because of difference in use pattern. As more refined information becomes available on carbaryl use, the Agency will refine its assessment accordingly.

In summary, with respect to residential handler risks, the Agency believes that the values presented in this assessment represent the highest quality results that could be produced given the exposure, use, and toxicology data that are available. However, there are certain elements where additional data are required. For example, it is difficult to ascertain where on a distribution certain input values may fall because the distributional data for exposure, application rates, acres treated and many other parameters are unrefined.

Postapplication: Like the residential handler assessment discussed above, the postapplication residential assessment for carbaryl is also complex in that noncancer MOE calculations were required based on the recently selected endpoints along with cancer risk calculations using a linear, low dose extrapolation model. Carbaryl residues persist in the environment as indicated in the available DFR and TTR data for periods where intermediate term as well as short term noncancer risk estimates are required. Cancer risks were calculated only for adults per current Agency policy.

The general population can be exposed through many different pathways that result from uses on lawns and turf, in gardens, on ornamental plants, and from treated pets. People can also be exposed from mosquito adulticide applications and uses in oyster beds. Carbaryl labels do not currently allow for indoor residential uses (e. g., crack and crevice). Settings where such exposures could occur would include around personal residences and in other areas frequented by the general public including parks, ball fields, and playgrounds. To represent the wide array of possible exposures, the Agency relies on the scenarios that have been defined in the SOPs For Residential Exposure Assessment and accompanying documents such as the overview presented to the FIFRA Science Advisory Panel. For turf uses, the Agency considered adults and toddlers (3 year olds) in the assessments. Adult activities included lawncare/ maintenance and also golfing. Toddler MOEs were calculated for playing on turf (using exposure data from the Jazzercize model) and also addressed nondietary ingestion (hand/ object tomouth and soil ingestion). Exposures from tree and garden uses were evaluated by considering adults and youth aged children (10 to 12 years old) doing gardening activities such as weeding and harvesting for different crop groups. Transfer coefficients from the fruiting vegetable crop group and the 69 deciduous tree crop group were used, as described in the SOPs For Residential Exposure Assessment to represent exposures for these scenarios. MOEs from treated pets were evaluated for toddlers again for whom exposures may occur from dermal contact and hand to mouth behavior. Adulticide mosquito applications were considered by first defining how much residues are deposited on the ground after a mosquito control application then using the same methods approaches from the lawncare assessment to address adults doing heavy yardwork or golfing and also children playing on treated turf.

The data that were used in the carbaryl residential postapplication assessment represent the best data and approaches that are currently available. To the extent possible, the Agency has attempted to use carbaryl specific data such as with the dislodgeable foliar residue (DFR) data used for the garden scenarios and the turf transferable residue (TTR) data used for the dermal component of the turf scenarios. When chemical specific data were unavailable, the Agency used the current approaches for residential assessment, many of which include recent upgrades to the SOPs. For example, for the toddler hand to mouth calculations, the TTR data were not used but a 5 percent transferability factor was applied to calculate residue levels appropriate for this exposure pathway. Another key approach to consider is the use of the dermal hug approach for pet products which was proposed at the September 1999 meeting of the FIFRA Science Advisory Panel. Oyster bed uses were evaluated based on guidance from Superfund and the Agency's SWIMODEL. There are also many embedded uncertainties that should be considered in the interpretation of this assessment such as those associated with the use of Jazzercize and with the nondietary ingestion calculations. Readers should consider these in the interpretation of the overall risk estimates. Readers should also consider the screening nature of the SOPs For Residential Exposure Assessment and how additional data could refine the results.

Finally, the Agency believes that the values presented in this assessment represent the highest quality results that could be produced based on the currently available postapplication exposure data. Certainly risk managers and other interested parties should consider the quality of individual inputs when interpreting the results and make decisions accordingly. It is difficult to ascertain where on a distribution the values which have been calculated fall because the distributional data for exposure, residue dissipation and many other parameters are unrefined. The Agency does believe, however, that the risks represent conservative estimates of exposure because maximum application rates are used to define residue levels upon which the calculations are based. Additionally, estimates are thought to be conservative even when measures of central tendency (e. g., most transfer coefficients are thought to be central tendency) are used because values that would be considered to be in the lower percentile aspect of any input parameter have not been used in the calculations.

There are many studies on carbaryl in the published literature or available from various governmental Agencies because it is so widely used that can be used to inform risk managers about the results of the risk assessment. For example, the Agency's Office of Research and Development, along with other Agencies, has funded a project entitled Pesticide Exposure in Children Living in Agricultural Areas along the United States Mexico Border Yuma County, Arizona. Preliminary results of this study indicate that carbaryl residues were identified in the dust of 20 percent of the 152 houses sampled and in approximately 24 percent in 25 samples collected in 6 schools in the same region. Also, in a 1995 study conducted by the Centers For Disease Control entitled Pesticide Residues In Urine Of Adults Living In 7 Hill RH et al (1995). Pesticide Residues in Urine of Adults Living in the United States: Reference Range Concentrations. Environmental Research 71: 99 108.

8 Pierce JP et al (1989). Tobacco Use in 1986  Methods and Basic Tabulations from Adult Use of Tobacco Survey. U. S. Department of Health and Human Services Publication Number OM90 2004. Office on Smoking and Health, Rockville, Maryland.

70 The United States: Reference Range Concentrations, 7 1000 adults were monitored via urine collection. One of the analytes measured in that study (1 naphthol) is a potential metabolite of carbaryl as well as of napthalene and napropamide. This metabolite was identified in 86 percent of the 1000 adults monitored where the mean value was 17 ppb and the 99th percentile was 290 ppb. These values were not used quantitatively in the risk assessment for carbaryl because of the associated uncertainties. However, the results from both studies indicate that carbaryl residues are present in areas frequented by the general population and that the scenarios which consider a broad range of exposures are reasonable.

4.4.5 Exposure from the Use of Tobacco Risks from carbaryl residues contained in tobacco products have been calculated based on a pyrolysis study in tobacco. In assessing exposure through use of tobacco, HED has assumed that the greatest exposure to carbaryl would come from cigarettes. Further, HED has assumed that the average U. S. smoker smokes 15 cigarettes per day. 8 Based on a pyrolysis study submitted by the registrant, residues of carbaryl total approximately 44.58 ppm in combined side stream and main stream tobacco smoke (Memorandum from Thurston Morton dated September 29, 1998, D230407). Since this is a composited sample of main stream and side stream smoke, it greatly exaggerates the actual exposure to the smoker, whose primary route of exposure is via main stream smoke. HED further assumes that 100 percent of that inhaled is absorbed (i. e., that none of the residue is exhaled along with the smoke). These assumptions result in an extreme overestimate of actual likely exposure. With the assumptions regarding residue levels and smoking frequency, and assuming an average body weight of 70 kg, HED estimated that exposure to carbaryl will not exceed 0.0096 mg/ kg/ day [44.58 : g/ g cigarette × 1 g/ cigarette × 15 cigarettes/ day × 1 mg/ 1000 : g ÷ 70 kg body weight = 0.0096 mg/ kg/ day].

The short term inhalation NOAEL is 1 mg/ kg/ day and is based on an developmental neurotoxicity study in the rat. Based on the inhalation NOAEL, the short term MOE for carbaryl exposure from the use of tobacco is estimated to be 104 even with the expectation that the calculated risks are an extreme overestimate. The residential target MOE is 100. The Agency has not examined intermediate or long term exposure to carbaryl via tobacco due to the severity and quantity of health effects associated with the use of tobacco products.

4.4.6 Other Residential Exposures This assessment for carbaryl reflects the Agency's current approaches for completing residential exposure assessments based on the guidance provided in the Draft: Series 875 Occupational and Residential Exposure Test Guidelines, Group B Postapplication Exposure Monitoring Test Guidelines, the Draft: Standard Operating Procedures (SOPs) for Residential Exposure Assessment, and the 9 There are several aggregate risk guidance documents that address both deterministic and probabilistic risk assessment approaches. The major science policy papers are available at www. EPA. Gov/ pesticides. The two key documents used for this assessment are 1) Updated Interim Guidance For Incorporating Drinking Water Exposure Into Aggregate Risk Assessments (Stasikowski, 8/ 1/ 99) and 2) HED RARC Format and Risk Characterization Guidance (12/ 22/ 00).

71 Overview of Issues Related to the Standard Operating Procedures for Residential Exposure Assessment presented at the September 1999 meeting of the FIFRA Scientific Advisory Panel (SAP). The Agency is, however, currently in the process of revising its guidance for completing these types of assessments. Modifications to this assessment shall be incorporated as updated guidance becomes available. This will potentially include expanding the scope of the residential exposure assessments by developing guidance for characterizing exposures from other sources already not addressed such as from spray drift; residential residue track in; exposures to farmworker children; and exposures to children in schools.

5.0 AGGREGATE RISK ASSESSMENTS AND RISK CHARACTERIZATION Based on the requirements of FQPA, aggregate risk assessments consider combined exposure from food, water and residential uses. Different types of aggregate assessments are required depending upon the use patterns for a chemical, the types of toxic effects associated with it, and the anticipated durations of exposure. A series of aggregate calculations have been completed for carbaryl. Section 5.1: Calculation of Aggregate Risks and DWLOCs describes how these values have been determined. Section 5.2: Acute Dietary Aggregate Risks and DWLOCs presents the results for the acute dietary only assessment. Section 5.3: Chronic Dietary Aggregate Risks and DWLOCs presents the results for the chronic dietary only assessment. Section 5.4: Shortterm Aggregate Risks and DWLOCs presents the results for the short term assessment which includes dietary intake and residential exposures. Section 5.5: Intermediate term Aggregate Risks and DWLOCs presents the results for the intermediate term assessment which includes dietary intake and residential exposures. Section 5.6: Aggregate Cancer Risks and DWLOCs presents the results for the cancer assessment that includes dietary intake and residential exposures. Section 5.7: Summary of Aggregate Risks provides an overview of the aggregate risk assessment results.

5.1 Calculation of Aggregate Risks and DWLOCs The Agency has developed several guidance documents describing the mathematical approaches used in calculating aggregate risks, the theoretical basis for these calculations, and the interpretation of the Food Quality Protection Act that requires the Agency to complete these kinds of calculations. 9 The underlying approach, regardless of the calculation type, is the same. The overall risks associated with a specific chemical are determined by its hazard database and its associated uncertainty factors or negligible risks if the concern is cancer. These two elements, combined, are used to define limits for the amount of overall exposures an individual can receive from the chemical. Once these limits have been defined, contributions from different sources of exposure are added together to see if the aggregate limit is exceeded.

The approach used by the Agency for these calculations is to add together estimates for dietary food intake and residential exposure (not used for acute assessment which is food and water 72 only) then subtract this from the exposure limit to see what portion of the limit is still available, if any. If there is room still left under the limit (i. e., dietary and residential exposures combined do not exceed the exposure limit), then drinking water exposures are considered by calculating DWLOCs (Drinking Water Levels of Concern). If there is no room left under the limit then the Agency knows the overall exposure limit has been exceeded even without considering drinking water intake and no further calculations are completed.

DWLOCs represent the concentration of carbaryl residues in drinking water that cannot be exceeded for aggregate exposures to exceed the overall exposure limit. If appropriate, DWLOCs are calculated by defining what part of the exposure limit has not been taken up from dietary and residential exposures which in turn defines the maximum amount of exposure one can have from drinking water. This can be a very simple calculation such as subtracting acute food exposures from the aPAD or chronic food intake and residential LADD estimates from the Q1* in a cancer calculation. In some cases it can be more complex such as for the short term assessment that required using the 1/ MOE approach described above in Section <IP_ADDRESS>: Residential Handler Noncancer Risks where water and dietary MOEs are added to the equation and compared to the target MOE. The equation was then solved for the water MOE which was in turn used to calculate the maximum drinking water exposure using the short term oral NOAEL. Maximum allowable drinking water exposure levels were then used to calculate concentrations in water based on standard daily consumption estimates and body weight factors for different subpopulations. Adults were assumed to intake 2 liters of water per day while small children and infants were assumed to intake 1 liter of water per day. Standard body weights were also used (i. e., 10 kg for small children, 60 kg for adult females, and 70 kg for other adult scenarios). The equation used to calculate the DWLOCs is presented below:

DWLOC( µg/ L) = [water exposure (mg/ kg bw/ day) x body weight (kg)] [water consumption (L) x 10 3 mg/ µg]

[Note: Water exposure, body weight, and consumption inputs are specific to certain exposure durations, toxicity concerns, and populations so they will vary from assessment to assessment.]

Once the DWLOCs have been calculated they were then compared to the Estimated Environmental Concentrations (EECs) which were defined by the Environmental Fate and Effects Division (Section 4.3.3: Modeling EECs, Table 10). Drinking water sources can include surface water or groundwater. EEC values were calculated for both. For surface water, computer modeling with the EPA PRZM3.12 and EXAMS 2.97.7 programs were used to estimate the concentration of carbaryl in surface water. Index reservoir scenarios corrected for Percent Cropped Area (PCA) for representative crops were used. The maximum calculated acute and chronic EECs (494 ppb and 28 ppb, respectively) resulted from use on citrus in Florida. In this case, the results for Florida provided the highest estimates; however, in Florida the majority of drinking water is derived from groundwater (> 90%) so high surface water concentrations do not necessarily indicate high exposure. As a result, both Florida and the results for Oregon apples have been considered in the aggregate assessment. The EECs for Oregon apples are the next highest values for both the acute and chronic estimates (144 and 9 ppb, respectively). Carbaryl chemical properties are outside the range of values for which SCI GROW was developed (i. e., aerobic metabolism is faster and its partition coefficient is larger which equates to 73 less leaching than the reference compounds  both factors indicate carbaryl degrades faster than the reference chemicals). SCI GROW estimates for groundwater EECs may not predict with complete accuracy, maximum levels because the concentrations calculated are 90 day averages. It is possible; therefore, that groundwater concentration peaks could not be identified. Groundwater levels are anticipated, however, to be more stable than surface water concentrations.

If the EEC is less than the corresponding DWLOC then the Agency has no concerns for aggregate risks for the scenario. If EECs exceed the DWLOC then aggregate risks are of concern. For carbaryl, there were many residential scenarios where the combined MOEs (i. e., combinations of inhalation, dermal and nondietary ingestion as appropriate) exceed the Agency's risk targets making the calculation of DWLOCs and aggregate risks for those scenarios inappropriate because exposure limits have already been exceeded. Additionally, acute dietary risks were also exceeded for infants and children (1 to 6 years old) at the 99.9 th percentile when the Carbamate Market Basket Survey (CMBS) was not considered in the assessment. However, the risk picture could substantively change if residential risks are refined based on updated use information from the carbaryl survey yet to be submitted to the Agency and the Agency chooses to regulate using the results of the CMBS.

Keeping this in mind, the Agency completed DWLOC and aggregate risk calculations for illustrative purposes using a number of representative exposure scenarios where the residential and dietary risk estimates did not already exceed the Agency's level of concern. For example, an acute assessment with CMBS results included and short term assessments where residential handler risks weren't already of concern were completed. The Agency also specifically selected some scenarios because they represent major residential uses (e. g., garden dusts) or specialized low exposure scenarios (e. g., mosquito control).

The Agency approach for calculating aggregate risks using different sources of data to create different exposure scenarios for illustrative purposes is consistent with Agency wide guidance for exposure assessment and risk characterization (e. g., PDP and carbamate market basket survey, various water scenarios, and selected residential scenarios). The Agency takes this approach to allow for more informed risk management decisions that consider as much available data as possible along with the uncertainties associated with those data. For example, it is appropriate to present results based on both PDP and the carbamate market basket survey. PDP data are routinely used in Agency risk assessments and the market basket study is of sufficient quality for incorporation in the risk assessment. However, there are uncertainties associated with the use of each data source (e. g., rubbing of fruit prior to extraction in the carbamate market basket survey which may decrease residue levels as described above in Section 4.2). 74 5.2 Acute Dietary Aggregate Risks and DWLOCs The results of the acute aggregate risk assessment are presented below in Table 17. These calculations are based on the use of the Carbamate Market Basket Survey (CMBS). Even with the use of the CMBS, aggregate risks when surface water is the source of drinking water, are still of concern for all infants, children (1 to 6 years old) and children (7 to 12 years old) regardless of whether or not Florida citrus or Oregon apple EECs are used (i. e., surface water is not a major drinking water source in Florida). If Florida citrus data are solely considered, aggregate risks are of concern for all subpopulations. Aggregate risks for all subpopulations are not of concern if groundwater is the source of drinking water. [Note: Most DWLOCs exceed the corresponding EECs for groundwater by an order of magnitude or greater. This should be considered along with the caution that it is possible that SciGrow might underestimate groundwater concentrations for carbaryl.]

Table 17: Acute DWLOC Calculations Based on Use of Carbamate Market Basket Survey Results Population Subgroup aPAD (mg/ kg/ day) Acute Food Exp. 99.9th% tile (mg/ kg/ day) Max. Acute Water Exposure (mg/ kg/ day) Acute DWLOC (ug/ L or ppb) EECs Surface Water (all PRZM/ EXMS) Ground Water (SciGrow) (ppb) FL Citrus (ppb) OR Apples (ppb) All Commodities Using 1989  1992 CFSII Consumption Data General Population 0. 010000 0.004623 0.005377 188 494 144 0.8 All Infants 0. 010000 0.007272 0.002728 27 494 144 0.8 Children (1 6 yrs) 0.010000 0.007344 0.002656 27 494 144 0.8 Children (7 12 yrs) 0.010000 0.006238 0.003762 38 494 144 0.8 Females (13 50 yrs) 0.010000 0.003546 0.006454 194 494 144 0.8 Males (13 19 yrs) 0.010000 0.002723 0.007277 255 494 144 0.8 Males (20+ yrs) 0.010000 0.003423 0.006577 230 494 144 0.8 Seniors (55+ yrs) 0.010000 0.004810 0.005190 182 494 144 0.8 All Commodities Using 1994 1998 CFSII Consumption Data General Population 0. 010000 0.004865 0.005135 180 494 144 0.8 All Infants 0. 010000 0.008091 0.001909 19 494 144 0.8 Children (1 6 yrs) 0.010000 0.009481 0.000519 5 494 144 0.8 Children (7 12 yrs) 0.010000 0.004921 0.005079 51 494 144 0.8 Females (13 50 yrs) 0.010000 0.004224 0.005776 173 494 144 0.8 Males (13 19 yrs) 0.010000 0.004515 0.005485 192 494 144 0.8 Males (20+ yrs) 0.010000 0.003359 0.006641 232 494 144 0.8 Seniors (55+ yrs) 0.010000 0.004649 0.005351 187 494 144 0.8 Note: For characterization purposes, the surface water EECs for Florida citrus exceed exposure limits alone, without even considering food intakes, for all populations. Additionally, the surface water EECs for Oregon apples exceed exposure limits alone, without even considering food intakes, for infants and children.

5.3 Chronic Dietary Aggregate Risks and DWLOCs The results of the chronic aggregate risk assessment are presented below in Table 18. Chronic aggregate risks were not of concern for any subpopulation regardless of the source of drinking water, even considering the Florida surface water EECs. There is one chronic residential exposure scenario associated with the use of pet collars where the MOEs for children are of concern. As such, exposure from pet collars was not included in the chronic DWLOC calculations because of the risk concerns for this scenario and to illustrate chronic, aggregate risks for all others who are not exposed to collars. 75 Table 18: Chronic DWLOC Calculations Population Subgroup cPAD (mg/ kg/ day) Chronic Food Exposure (mg/ kg/ day) Max. Chronic Water Exposure (mg/ kg/ day) Chronic DWLOC (ug/ L or ppb) EECs Surface Water (all PRZM/ EXMS) Ground Water (SciGrow) (ppb) FL Citrus (ppb) OR Apples (ppb) All Commodities Using 1989  1992 CFSII Consumption Data General Population 0. 010000 0.000032 0.009968 349 28 9 0. 8 All Infants 0. 010000 0.000054 0.009946 100 28 9 0. 8 Children (1 6 yrs) 0.010000 0.000057 0.009943 99 28 9 0. 8 Children (7 12 yrs) 0.010000 0.000036 0.009964 100 28 9 0. 8 Females (13 50 yrs) 0.010000 0.000026 0.009974 299 28 9 0. 8 Males (13 19 yrs) 0.010000 0.000022 0.009978 349 28 9 0. 8 Males (20+ yrs) 0.010000 0.000031 0.009969 349 28 9 0. 8 Seniors (55+ yrs) 0.010000 0.000031 0.009969 349 28 9 0. 8 All Commodities Using 1994 1998 CFSII Consumption Data General Population 0. 010000 0.000035 0.009965 349 28 9 0. 8 All Infants 0. 010000 0.000059 0.009941 99 28 9 0. 8 Children (1 6 yrs) 0.010000 0.000074 0.009926 99 28 9 0. 8 Children (7 12 yrs) 0.010000 0.000034 0.009966 100 28 9 0. 8 Females (13 50 yrs) 0.010000 0.000028 0.009972 299 28 9 0. 8 Males (13 19 yrs) 0.010000 0.000026 0.009974 349 28 9 0. 8 Males (20+ yrs) 0.010000 0.000032 0.009968 349 28 9 0. 8 Seniors (55+ yrs) 0.010000 0.000030 0.009970 349 28 9 0. 8 5.4 Short term Aggregate Risks and DWLOCs The results of the short term aggregate risk assessment are presented below in Table 19. The exposure scenarios which were considered in this assessment represent a broad range of carbaryl uses. The only scenarios for toddlers that were included were for the mosquito control and oyster bed uses. The Agency has risk concerns for all other scenarios that were addressed for toddlers based on residential exposures alone including uses on turf and uses on pets (see Section <IP_ADDRESS>: Residential Postapplication Exposure and Noncancer Risks). In the residential assessment, youth (ages 10 to 12) were also considered in home garden scenarios. The risk estimates for these children are similar to that for adults so aggregate risks were calculated only for adults with the stipulation that the results represent both populations (i. e., risks are actually slightly worse for adults). For adults, the following postapplication exposures were considered: after mosquito control (doing heavy yardwork/ lawncare); golfing; gardening (highest exposure activity  tree fruit harvest); and oyster harvesting. Adults doing heavy lawncare tasks after normal applications to turf were of concern for residential exposure alone so they were not considered in the aggregate assessment. Additionally, several aggregate assessments for homeowner handlers (most at average application rates) were completed based on application of dusts (gardens and pets): hose end sprayer; liquid spray spot lawn treatments; and broadcast application of granulars to lawns. The handler scenarios are numbered and these correspond to the residential risk assessment scenario numbers. Risks for these handler scenarios at higher application rates (e. g., label maximums) were of concern for residential exposure alone so they were not considered in the aggregate assessment. All calculations for adults were completed for both women and men. Results were similar for both populations.

If surface water EECs based on Oregon apples or groundwater EECs from Sci Grow are considered, aggregate risks are not of concern for the selected scenarios. If EECs from Florida citrus are considered, aggregate risks are not of concern for the selected scenarios except for application of dusts 76 to gardens at the average rate keeping in mind that surface water is not a major drinking water source in Florida. [Note: Most DWLOCs exceed the corresponding EECs for groundwater by orders of magnitude. This should be considered along with the caution that it is possible that Sci Grow might underestimate groundwater concentrations for carbaryl.]

Table 19: Short term Aggregate Risk and DWLOC Calculations Using 1989 1992 CFSII Consumption Data Population Subgroup Target Agg. MOE Food MOE Nondietary Ing. MOE Dermal MOE Inhal. MOE Aggregat e MOE Water MOE Allowable Water Exposure (mg/ kg/ day) DWLOC (ug/ L or ppb) EECs Surface Water (all PRZM/ EXMS) Ground Water (SciGrow )

(ppb) FL Citrus (ppb) OR Apples (ppb) Postapplication Children Children (1 6 yrs) Aerial Mosquito Day 0 100 17544 562 2211 NA 437 130 0.007710 116 28 9 0.8 Children (1 6 yrs) Oyster Bed Day 0 100 17544 51681 68909 NA 11006 101 0.009909 149 28 9 0.8 Postapplication Adult Males Adult Male Aerial Mosquito Day 0 Lawncare 100 32258 NA 3700 NA 3319 103 0.009699 340 28 9 0.8 Adult Male Golfing Day 0 Max Rate 100 32258 NA 624 NA 612 120 0.008366 293 28 9 0.8 Adult Male Garden Day 0 High Expo. 100 32258 NA 579 NA 569 121 0.008242 289 28 9 0.8 Adult Male Oyster Bed Use Day 0, Swim 100 32258 301815 10856944 NA 29065 100 0.009966 349 28 9 0.8 Adult Male Consumer Product Handlers Adult Male Scen. #2 Garden Dust Avg Rate 100 32258 NA 120 1019 107 1580 0.000633 22 28 9 0.8 Adult Male Scen #3 Gard. Hose End, Avg Rate 100 32258 NA 158 134615 157 274 0.003648 128 28 9 0.8 Adult Male Scen #8 Lawn Spot Liquids 100 32258 NA 509 17500 487 126 0.007948 278 28 9 0.8 Adult Male Scen #9 Dusting Dog Avg Rate 100 32258 NA 163 1077 141 343 0.002913 102 28 9 0.8 Adult Male/ Scen # 12 Lawn Broadcast Granular 100 32258 NA 490 18315 470 127 0.007874 276 28 9 0.8 Postapplication Adult Females Adult Female Aerial Mosquito Day 0 Lawncare 100 38462 NA 3700 NA 3375 103 0.009704 291 28 9 0.8 Adult Female Golfing Day 0 Max Rate 100 38462 NA 624 NA 614 119 0.008371 251 28 9 0.8 Adult Female Garden Day 0 High Expo. 100 38462 NA 579 NA 570 121 0.008247 247 28 9 0.8 Adult Female Oyster Bed Use Day 0, Swim 100 38462 301815 10856944 NA 34007 100 0.009971 299 28 9 0.8 Adult Female Consumer Product Handlers Adult Female Scen. #2 Garden Dust Avg Rate 100 38462 NA 120 1019 107 1568 0.000638 19 28 9 0.8 Adult Female Scen #3 Gard. Hose End, Avg Rate 100 38462 NA 158 134615 158 274 0.003653 110 28 9 0.8 Adult Female Scen #8 Lawn Spot Liquids 100 38462 NA 509 17500 488 126 0.007953 239 28 9 0.8 Adult Female Scen #9 Dusting Dog Avg Rate 100 38462 NA 163 1077 141 343 0.002918 88 28 9 0.8 Adult Female/ Scen # 12 Lawn Broadcast Granular 100 38462 NA 490 18315 472 127 0.007879 236 28 9 0.8 5.5 Intermediate term Aggregate Risks and DWLOCs Separate intermediate term aggregate risk and DWLOC calculations were not completed for carbaryl because the short term aggregate risk estimates essentially present the same results since the hazard inputs are numerically identical. The only major differences would be the postapplication results 77 where, instead of a single day exposure estimate, the exposures represent a 30 day average. The DWLOCs were not of concern for the short term exposure scenarios and they would not be expected to be of concern for the intermediate term scenarios since the exposures would be lowered because an average was used instead of a single day, higher exposure estimate.

5.6 Aggregate Cancer Risks and DWLOCs The results of the aggregate cancer risk assessment are presented below in Table 20. The exposure scenarios which were considered in this assessment represent a broad range of carbaryl uses. The same scenarios for adults were considered as in the short term assessment described above in Section 5.4: Short term Aggregate Risks and DWLOCs. Aggregate cancer risks were not of concern for any subpopulation regardless of the source of drinking water, even considering the Florida surface water EECs.

Table 20: Aggregate Cancer Risk and DWLOC Calculations Using 1989 1992 CFSII Consumption Data Population Subgroup Q1* (mg/ kg/ day) 1 Negligible Risk Level Target Maximum Exposure (mg/ kg/ day) Chronic Food Exposure (mg/ kg/ day) Residential Exposure LADD (mg/ kg/ day) Aggregate Cancer Risk (Food & Residential) Maximum Water Exposure (mg/ kg/ day) DWLOC (ug/ L or ppb) EECs Surface Water (all PRZM/ EXMS) Ground Water (SciGrow) (ppb) FL Citrus (ppb) OR Apples (ppb)

Postapplication Adult Males Adult Male/ Aerial Mosquito Day 0 Lawncare 8.75x10 4 1.0x10  6 0.001143 0.000031 0.00000067 2.77E 008 0.001111 39 28 9 0.8 Adult Male/ Golfing Day 0 Max Rate 8.75x10 4 1.0x10  6 0.001143 0.000031 0.00000400 3.06E 008 0.001108 39 28 9 0.8 Adult Male/ Garden Day 0 High Expo. 8.75x10 4 1.0x10  6 0.001143 0.000031 0.00000857 3.46E 008 0.001103 39 28 9 0.8 Adult Male/ Oyster Bed Use Day 0, Swim 8.75x10 4 1.0x10  6 0.001143 0.000031 0.00000001 2.71E 008 0.001112 39 28 9 0.8 Adult Male Consumer Product Handlers Adult Male/# 2 Garden Dust Avg Rate 8.75x10 4 1.0x10  6 0.001143 0.000031 0.00004343 6.51E 008 0.001068 37 28 9 0.8 Adult Male/# 3 Garden Hose End, Avg Rate 8.75x10 4 1.0x10  6 0.001143 0.000031 0.00003143 5.46E 008 0.001080 38 28 9 0.8 Adult Male/# 8 Lawn Spot Liquids 8.75x10 4 1.0x10  6 0.001143 0.000031 0.00000987 3.58E 008 0.001102 39 28 9 0.8 Adult Male/# 9 Dusting Dog Avg Rate 8.75x10 4 1.0x10  6 0.001143 0.000031 0.00003223 5.53E 008 0.001080 38 28 9 0.8 Adult Male/# 12 Lawn Broadcast Granular 8.75x10 4 1.0x10  6 0.001143 0.000031 0.00001025 3.61E 008 0.001102 39 28 9 0.8 Postapplication Adult Females Adult Female/ Aerial Mosquito Day 0 Lawncare 8.75x10 4 1.0x10  6 0.001143 2.6E 005 0.00000067 2.33E 008 0.001116 34 28 9 0.8 Adult Female/ Golfing Day 0 Max Rate 8.75x10 4 1.0x10  6 0.001143 2.6E 005 0.00000400 2.63E 008 0.001113 33 28 9 0.8 Adult Female/ Garden Day 0 High Expo. 8.75x10 4 1.0x10  6 0.001143 2.6E 005 0.00000857 3.03E 008 0.001108 33 28 9 0.8 Adult Female/ Oyster Bed Use Day 0, Swim 8.75x10 4 1.0x10  6 0.001143 2.6E 005 0.00000001 2.28E 008 0.001117 34 28 9 0.8 Adult Female Consumer Product Handlers Adult Female/# 2 Garden Dust Avg Rate 8.75x10 4 1.0x10  6 0.001143 2.6E 005 0.00004343 6.08E 008 0.001073 32 28 9 0.8 Adult Female/# 3 Garden Hose End, Avg Rate 8.75x10 4 1.0x10  6 0.001143 2.6E 005 0.00003143 5.03E 008 0.001085 33 28 9 0.8 Adult Female/# 8 Lawn Spot Liquids 8.75x10 4 1.0x10  6 0.001143 2.6E 005 0.00000987 3.14E 008 0.001107 33 28 9 0.8 Adult Female/# 9 Dusting Dog 8.75x10 4 1.0x10  6 0.001143 2.6E 005 0.00003223 5.10E 008 0.001085 33 28 9 0.8 Adult Female/# 12 Lawn Broadcast Granular 8.75x10 4 1.0x10  6 0.001143 2.6E 005 0.00001025 3.17E 008 0.001107 33 28 9 0.8 78 5.7 Summary of Aggregate Risks In many residential scenarios, MOEs exceed the Agency's risk targets making the calculation of DWLOCs and aggregate risks for those scenarios inappropriate because exposure limits have already been exceeded. Additionally, acute dietary risks were also exceeded for infants and children (1 to 6 years old) at the 99.9 th percentile when the Carbamate Market Basket Survey (CMBS) was not considered in the assessment. However, the risk picture could substantively change if residential risks are refined based on updated use information from the carbaryl use survey yet to be submitted to the Agency and the Agency regulates using the results of the CMBS. The Agency approach for calculating aggregate risks using different sources of data to create different exposure scenarios for illustrative purposes is consistent with Agency wide guidance for exposure assessment and risk characterization (e. g., PDP and carbamate market basket survey, various water scenarios, and selected residential scenarios). The Agency takes this approach to allow for more informed risk management decisions that consider as much available data as possible along with the uncertainties associated with those data. For example, it is appropriate to present results based on both PDP and the carbamate market basket survey. PDP data are routinely used in Agency risk assessments and the market basket study is of sufficient quality for incorporation in the risk assessment. However, there are uncertainties associated with the use of each data source (e. g., rubbing of fruit prior to extraction in the carbamate market basket survey).

Keeping this in mind, the Agency completed DWLOC and aggregate risk calculations for illustrative purposes using a number of representative exposure scenarios where the residential and dietary risk estimates did not already exceed the Agency's level of concern. For example, an acute assessment with CMBS results included and short term assessments where residential handler risks weren't already of concern were completed. The highest EECs for surface water were from Florida citrus but most drinking water in Florida is from groundwater. Therefore, results from surface water in Florida and the next highest values (Oregon apples) were considered in the assessment.

The acute aggregate assessment indicates that even with the use of the Carbamate Market Basket Survey (CMBS), aggregate risks when surface water is the source of drinking water, are still of concern for all infants, children (1 to 6 years old) and children (7 to 12 years old) regardless of whether or not Florida citrus or Oregon apple EECs are used (i. e., surface water is not a major drinking water source in Florida). If Florida citrus results are solely considered, aggregate risks are of concern for all subpopulations. Surface water EECs for Florida citrus exceed exposure limits, without even considering food intakes, for all populations. The surface water EECs for Oregon apples exceed exposure limits alone, without even considering food intakes, for infants and children. Acute aggregate risks for all subpopulations are not of concern if groundwater is the source of drinking water. Chronic aggregate risks were not of concern for any subpopulation regardless of the source of drinking water, even considering the Florida surface water EECs. In the short term assessment, the Agency selected representative scenarios where residential risks alone were not of concern including mosquito control, oyster harvesting, golfing, garden harvest, and several handler scenarios (all at average rates, max rate scenarios were of concern for residential exposures alone). If surface water EECs based on Oregon apples or groundwater EECs from SciGrow are considered, aggregate risks are not of concern for the selected scenarios. If EECs from Florida citrus are considered, aggregate risks are not of concern for the selected scenarios except for application of dusts to gardens. Separate intermediate term aggregate risk and DWLOC calculations were not completed for carbaryl because the short term aggregate risk estimates essentially presented the same results since the hazard inputs were numerically identical. The only major differences would be the postapplication results where, instead of a single day exposure 79 estimate, the exposures represented a 30 day average. Aggregate cancer risks were not of concern for any subpopulation regardless of the source of drinking water, even considering the Florida surface water EECs.

6.0 CUMULATIVE RISK The Food Quality Protection Act (1996) stipulates that when determining the safety of a pesticide chemical, EPA shall base its assessment of the risk posed by the chemical on, among other things, available information concerning the cumulative effects to human health that may result from dietary, residential, or other non occupational exposure to other substances that have a common mechanism of toxicity. The reason for consideration of other substances is due to the possibility that low level exposures to multiple chemical substances that cause a common toxic effect by a common mechanism could lead to the same adverse health effect as would a higher level of exposure to any of the other substances individually. A person exposed to a pesticide at a level that is considered safe may in fact experience harm if that person is also exposed to other substances that cause a common toxic effect by a mechanism common with that of the subject pesticide, even if the individual exposure levels to the other substances are also considered safe.

Carbaryl is a member of the carbamate class of pesticides. This class also includes the aldicarb, methomyl and oxamyl among others. HED did not perform a cumulative risk assessment as part of this reregistration review for carbaryl because HED has not yet initiated a review to determine if there are any other chemical substances that have a mechanism of toxicity common with that of carbaryl. For purposes of this reregistration decision, EPA has assumed that carbaryl does not have a common mechanism of toxicity with other substances.

The registrant must submit, upon EPA's request and according to a schedule determined by the Agency, such information as the Agency directs to be submitted in order to evaluate issues related to whether carbaryl shares a common mechanism of toxicity with any other substance and, if so, whether any tolerances for carbaryl need to be modified or revoked. If HED identifies other substances that share a common mechanism of toxicity with carbaryl, HED will perform aggregate exposure assessments on each chemical, and will begin to conduct a cumulative risk assessment once the final guidance HED will use for conducting cumulative risk assessments is available.

HED has recently developed a framework that it proposes to use for conducting cumulative risk assessments on substances that have a common mechanism of toxicity. This guidance reflects recent revisions based on review and comment from earlier guidance issued on June 30, 2000 (65 FR 40644 40650) that is available from the OPP Website at: http:// www. epa. gov/ fedrgstr/ EPAPEST 2000/ June/ Day 30/ 6049. pdf. The recently revised guidance is entitled Guidance on Cumulative Risk Assessment of Pesticide Chemicals That Have A Common Mechanism Of Toxicity (January 14, 2002). In the guidance, it is stated that a cumulative risk assessment of substances that cause a common toxic effect by a common mechanism will not be conducted until an aggregate exposure assessment of each substance has been completed.

Before undertaking a cumulative risk assessment, HED will follow procedures for identifying chemicals that have a common mechanism of toxicity as set forth in the "Guidance for Identifying Pesticide Chemicals and Other Substances that Have a Common Mechanism of Toxicity" (64 FR 5795 5796, February 5, 1999). HED will also address issues described in the document entitled 80 Consideration of the FQPA Safety Factor and Other Uncertainty Factors In Cumulative Risk Assessment of Chemicals Sharing a Common Mechanism of Toxicity (Draft: February 28, 2002).

7.0 OCCUPATIONAL RISK ASSESSMENT This section of the risk assessment addresses exposures to individuals who are exposed as part of their employment. These exposures can occur because people have contact with carbaryl residues while using commercial products containing carbaryl (i. e., handlers) or by being in areas that have been previously treated (postapplication workers). A thorough understanding of how carbaryl is used is critical to the development of a quality risk assessment. Because this information is also critical to the dietary and residential exposure assessments presented above, available use information has already been summarized. Please refer to Section 4.1: Summary of Registered Uses for information on how carbaryl is used. All calculations for occupationally exposed people are based on this information. Also, for more detailed information pertaining to the occupational risk calculations, please refer to the Occupational and Residential Exposure Assessment (D281418) prepared by Jeff Dawson. The document D281418 contains detailed descriptions of the data used, methods, and risks calculated for each scenario.

Section 7.1: Occupational Handler Risk Assessment describes the data, methods, and risk results (both cancer and noncancer) associated with the use of commercial products which contain carbaryl. Section 7.2: Occupational Postapplication Risk Assessment describes the data, methods, and risk results associated with exposures to workers as they complete activities required for the production and maintenance of crops or other areas such as turf that might require the use of carbaryl. Section 7.3: Occupational Risk Characterization provides information pertaining to the quality of the assessment including data used, uncertainties with the methods, and any other information that might be used to describe the quality of the results. Section 7.4: Human and Domestic Animal Incident Data Review describes the analysis conducted by Agency epidemiologists.

7.1 Occupational Handler Risk Assessment The Agency completes occupational handler risk assessments using scenarios as the basis for the calculations as described in the U. S. EPA Guidelines For Exposure Assessment. For commercial pesticide products, the Agency categorizes handler exposures based on the kinds of formulations (e. g., liquids or various solids), the kinds of equipment used to make applications (e. g., groundboom, aerial, or airblast), the nature of the task (e. g., mixing/ loading, applying, or both combined), and the level of personal protection used. Identifying the duration of exposure is also a critical element in the development of a risk assessment to ensure that the proper hazard component is used.

For carbaryl uses, the Agency identified 28 major occupational exposure scenarios based on the types of equipment and techniques that potentially can be used for carbaryl applications. Most of the scenarios were classified as having short term and intermediate term exposures (up to 30 days and 30 days to several months, respectively). A few other scenarios have also been addressed that are thought to have long term or chronic exposures (several months to every working day) associated with them in the greenhouse and floriculture industry.

The quantitative exposure/ risk assessment developed for occupational handlers was based on the following scenarios. [Note: The numbers correspond to the tracking system included in D281418.] 81 Mixing/ Loading (1a) Dry Flowable for Aerial/ Chemigation in Agriculture; (1b) Dry Flowable for Airblast; (1c) Dry Flowable for Groundboom; (1d) Dry Flowable for High Pressure Handwand and Right of Way Sprayers; (1e) Dry Flowable for LCO Applications; (1f) Dry Flowable for Aerial Wide Area Uses; (2a) Granular for Aerial; (2b) Granular for Broadcast Spreader; (3a) Liquids for Aerial/ Chemigation; (3b) Liquids for Airblast; (3c) Liquids for Groundboom; (3d) Liquids for High Pressure Handwand and Right of Way Sprayers; (3e) Liquids for LCO Applications; (3f) Liquids for Aerial Wide Area Uses; (3g) Liquids for Ground Wide Area Uses; (4a) Wettable Powder for Aerial/ Chemigation; (4b) Wettable Powder for Airblast; (4c) Wettable Powder for Groundboom; (4d) Wettable Powder for High Pressure Handwand and Right of Way Sprayers; (4e) Wettable Powder for LCO Applications; (4f) Wettable Powder for Aerial Wide Area Uses;

Applicator: (5a) Aerial/ Liquid Application; (5b) Aerial/ Liquid Wide Area Application; (5c) Aerial/ Granular Application; (6a) Airblast Application; (6b) Wide Area Ground Fogger (Airblast as surrogate); (7) Groundboom Application; (8) Solid Broadcast Spreader Application; (9) Aerosol Can Application; (10) Trigger Sprayer (RTU) Application; (11) Right of Way Sprayer Application; (12) High Pressure Handwand Application; (13) Veterinary Technician/ Animal Groomer Liquid Application; (14) Veterinary Technician/ Animal Groomer Dust Application; (15) Granulars/ Bait and Pellets Dispersed by Hand; (16) Granulars/ Bait and Pellets Dispersed with Spoon; 82 Mixer/ Loader/ Applicator: (17) Low Pressure/ High Volume Turfgun Application; (18a) Wettable powder, Low pressure handwand; (18b) Liquid: Low Pressure Handwand; (19) Backpack; (20) Granular Belly Grinder; (21) Push type Granular Spreader; (22) Handheld Fogger; (23) Powered Backpack; (24) Granular Backpack; (25) Tree Injection; (26) Drenching/ Dipping Seedlings For Propagation; (27) Sprinkler Can;

Flaggers: (28a) Flagging For Liquid Sprays; and (28b) Flagging For Granular Applications.

For each of these scenarios, risk calculations were completed based on eight levels of personal protection that were defined based on different combinations of the following:

1) baseline protection (typical work clothing or a long sleeved shirt and long pants, no respiratory protection and no chemical resistant gloves);

2) minimum personal protective equipment (baseline scenario with the use of chemical resistant gloves and a dust/ mist respirator with a protection factor of 5);

3) maximum personal protective equipment (baseline scenario with the use of an additional layer of clothing (e. g., a pair of coveralls), chemical resistant gloves, and an air purifying respirator with a protection factor of 10);

4) engineering controls (use of an appropriate engineering control such as a closed tractor cab or closed loading system for granulars or liquids).

Current labels mostly require single layer clothing, chemical resistant gloves, and no respirator.

Data and Assumptions A series of assumptions and exposure factors served as the basis for completing the occupational handler risk assessments, as described below. The assumptions and factors used in the risk calculations are consistent with current Agency policy for completing occupational exposure assessments (e. g., PHED Surrogate Exposure Guide and Exposac Policy 9: Standard Values For Daily Acres Treated In Agriculture). [Note: PHED is a database that contains monitored field data used for assessments. See Section 4.4.2 Residential Handler Risk Assessment above for further information.] 83 ° Average body weight of an adult handler is 70 kg as described in the residential handler assessments (see Section 4.4.2).

° Several generic protection factors were used to calculate handler exposures. The protection factors used for clothing layers (i. e., 50%) and gloves (90%) have not been completely evaluated by the Agency. Additionally, protection factor was used to estimate exposures that involve engineering controls if required (98%). The values used for respiratory protection (i. e., PF 5 or PF 10) are based on the NIOSH Respirator Decision Logic.

° For cancer risk calculations, a value of 30 application events per year for all commercial applicator scenarios and 10 days per year to account for private growers was used. These values are supported by the data included in the University of California studies of seasonal labor in California and the recent Department of Labor National Agricultural Worker Survey (NAWS). The exposure duration values used by HED in the cancer risk assessment are consistent with those used for other chemicals (i. e., 35 working years and 70 year lifetime).

° In many scenarios, it is likely that a grower would mix, load, and apply chemicals all in one day because of limited labor, efficiency, or many other reasons. In most cases, mixing/ loading and application are considered separate job functions because of the available data and also it allows for more flexibility in the risk management phase (e. g., assigning requirements for specific types of protective equipment).

° Flagging during aerial applications has been addressed even though it may be limited in nature (10 to 15% of aerial application operations). Engineering controls (e. g., Global Positioning Satellite technology) are now predominantly used by pilots as indicated by the 1998 National Agricultural Aviation Association (NAAA) survey of their membership.

° The maximum application rates allowed by labels were used in the risk assessments. If additional information, such as average or typical rates, were available, these values were used as well in order to allow risk managers to make a more informed risk management decision. Average application rates were available from the SMART meeting and BEAD's QUA.

° The average occupational workday is assumed to be 8 hours. The daily areas to be treated were defined for each handler scenario (in appropriate units) by determining the amount that can be reasonably treated in a single day (e. g. acres, animals). The factors used for the carbaryl assessment are the same as those detailed in the HED Science Advisory Committee on Exposure Policy 9: Standard Values for Daily Acres Treated in Agriculture. The daily volumes handled and acres treated, excerpted from the policy, in each occupational scenario include: 10 The veterinary and fireant treatments are not included in the policy but represent values that have been used by HED in previous assessments.

84 ° Aerial applications: 1200 acres for large field crops and forest treatments, 350 acres for other field crops, and 7500 acres for mosquito control adulticide applications; ° Groundboom: 200 acres for large field crops (e. g., wheat and corn), 80 acres treated for other field crop groundboom applications, and 40 acres on golf course turf; ° Airblast: 40 acres treated for agricultural applications; ° 8 pet animals treated per day for veterinary and professional groomer uses 10 ; ° 1000 gallons of spray solution prepared when mixing/ loading liquids for high pressure handwand application or making the application; ° 40 gallons when mixing/ loading/ applying liquids with a backpack sprayer or a low pressure handwand sprayer; ° 10 mounds per day treated for fire ant applications. 10 ° For direct pet animal treatments, the Residential SOPs, were used to define the amount of chemical that can be used to treat a single animal, which in turn was used to calculate total human dose levels. The actual per animal application rates used were ½ of a 6 oz bottle for liquid shampoos (0.5%) and ½ of 4 lb container for animal powders (10%).

° Ultra low volume applications for uses, such as adulticide mosquito control, were considered using a large acreage estimate to aerial applicators. The mosquito adulticide uses were evaluated in the same manner as other chemicals used for that purpose (e. g., the same acreage estimates were used as for other chemicals like fenthion and naled).

° There were several scenarios which were identified for which no appropriate exposure data are known to exist. These include: animal grooming dust application; dust applications in agriculture; handheld fogging for mosquito and other pest treatments; power backpack application; tree injection; and drenching/ dipping seedlings (the mixing/ loading component only of this scenario has been addressed quantitatively).

The unit exposure values (mg ai exposure/ lb ai handled) used in this assessment were predominantly based on PHED and summarized in the surrogate exposure guidance. In addition to PHED, five studies were used by the Agency. One used carbaryl to quantify exposures for professional dog groomers. Two were completed by Aventis Crop Science using other chemicals that quantified exposures to granular products using a backpack application device. One was submitted by Bayer (now in the process of acquiring Aventis Crop Science and with a signed PHED data waiver) that quantified exposures using a ready to use trigger sprayer. Lastly, an ORETF (Outdoor Residential Exposure Task Force, of which Aventis Crop Science is a member) study that quantified exposures of professional 11 Non ORETF data included in MRIDs 451672 01 and 452507 01 were from studies submitted by Aventis Crop Science. The propoxur trigger sprayer study has a signed PHED data waiver but has not been included into PHED. It also is the property of Bayer Crop Science which has recently acquired Aventis Crop Science. Some of the handler exposure data used in this assessment are from the ORETF, of which Aventis Crop Science, is a member.

85 lawncare operators using granular and liquid products. There are no data compensation issues with any of these data. 11 In all cases, what appears to be the best available data have been used to complete the calculations.

7.1.1 Occupational Handler Non Cancer Risks Noncancer risks were calculated using the MOE approach, as described under <IP_ADDRESS>. The major differences are that personal protective devices are used and longer duration exposures (i. e., intermediate term and chronic) have been considered as appropriate. Risk estimates for short and intermediate term exposures are similar because all numerical inputs for both durations and the target MOEs were identical. A NOAEL from the 21 day dermal toxicity study in rats using technical grade carbaryl was used to calculate results for both durations (i. e., 20 mg/ kg/ day). A NOAEL from the developmental neurotoxicity study in rats, that also observed at the same level in a subchronic neurotoxicity study in rats (i. e., 1 mg/ kg/ day), was used to calculate inhalation risks. The target MOE was 100 for all assessments. In the chronic assessments, a LOAEL (3.1. mg/ kg/ day) has been used from a 1 year dog feeding study for both dermal and inhalation exposures (with a dermal absorption factor of 12.7 percent applied). The target MOE for the chronic assessments is 300 because a LOAEL was used instead of a NOAEL.

Short/ Intermediate term Risks: In most scenarios, MOEs meet or exceed the required uncertainty factor of 100 at some level of personal protection. For the most part, current label requirements for personal protection (single layer clothing, gloves, and no respirator) appear to be generally inadequate for most scenarios except for operations where exposures are low and the amount of chemical used is also low. Table 21 summarizes the results for short term and intermediate term occupational handlers. [Note: Scenarios where MOEs are still of concern (i. e., <100) for any personal protection considered are highlighted and just the minimum required personal protective equipment (PPE) is highlighted if it exceeds current label requirements but target MOEs can be achieved at higher than label requirements for mitigation.]

Table 21: Summary of Short/ Intermediate Term Occupational Handler Noncancer Risks Scenario Rate (lb ai/ acre)

[unless noted] Area Treated (acres/ day)

[unless noted] Risk Summary MOEs Min. Req. PPE Mixer/ Loaders 1a Dry Flowable: Aerial/ Chemigation 1 2 (wheat/ corn) 2 5 (veg., stone fruit, 24C on oysters) 1200 350 363 726 498 1244 EC EC 1b Dry Flowable: Airblast 7.5 16 (various fruit & nut trees) 5 (nuts) 1.1 3 (pome & stone fruit, grapes) 40 40 40 1360 2902 101 143 391 EC SL/ GL/ PF5 Baseline Table 21: Summary of Short/ Intermediate Term Occupational Handler Noncancer Risks Scenario Rate (lb ai/ acre)

[unless noted] Area Treated (acres/ day)

[unless noted] Risk Summary MOEs Min. Req. PPE 86 1c Dry Flowable: Groundboom 1.5 2 (wheat/ corn) 2 (strawberry/ veg) 8 (turf/ golf courses) 4 (turf/ golf courses) 200 80 40 40 2177 2902 107 2721 108 EC Baseline EC Baseline 1d Dry Flowable: High Press HW/ ROW Sprayer 4 lb ai/ 100 gal (poultry) 1000 gal 430 Baseline 1e Dry Flowable: Low press./ High Vol. Turfgun 4 8 (LCO on turf) 5 430 860 Baseline 1f Dry Flowable: Wide area aerial 2 (rangeland/ forestry) 7500 58 MOE < 100 2a Granular: Aerial Application 2 (corn) 2 (corn) 1200 350 688 146 EC SL/ GL/ PF5 2b Granular: Solid broadcast spreader 1.5 (wheat/ corn) 2 (wheat/ corn) 2 (vegetables) 6 (turf/ golf courses) 9 (turf/ golf courses) 200 200 80 40 40 110 256 206 138 284 Baseline SL/ GL/ PF5 Baseline Baseline SL/ GL/ PF5 3a Liquid: Aerial/ Chemigation 1.5 2 (wheat, max corn) 1 (avg. corn) 5 (stone fruit) 2 (vegetables) 1200 1200 350 350 57 76 114 78 103 All MOEs < 100 EC MOE< 100 DL/ GL/ PF10 3b Liquid: Airblast Application 16 (Citrus 24C in California) 7.5 (Citrus) 5 (Nuts) 1.1 3 (Grapes, pome & stone fruit) 40 40 40 40 100 168 149 248 677 DL/ GL/ PF10 SL/ GL/ PF5 SL/ GL/ NR SL/ GL/ NR 3c Liquid: Groundboom 1.5 (wheat) 2 (corn) 2 (strawberries) 8 (turf/ golf courses) 4 (turf/ golf courses) 200 200 80 40 40 168 126 186 157 186 SL/ GL/ PF5 SL/ GL/ PF5 SL/ GL/ NR SL/ GL/ PF5 SL/ GL/ NR 3d Liquid: High Press HW/ ROW Sprayer 4 lb ai/ 100 gal (poultry) 1000 gal 745 SL/ GL/ NR 3e Liquid: Low press./ High Vol. Turfgun 4 8 (LCO on turf) 5 745 1489 SL/ GL/ NR 3f Liquid: Wide area aerial 2 (Range/ Forestry) 0.016 (Mosquito adulticide) 0.15 (Mosquito adulticide) 1 (Mosquito adulticide) 7500 7500 7500 7500 9 248 121 18 MOE < 100 SL/ GL/ NR EC MOE < 100 3g Liquid: Wide area ground 0.016 (Mosquito adulticide) 0.15 (Mosquito adulticide) 1 (Mosquito adulticide) 3000 3000 3000 621 112 45 SL/ GL/ NR SL/ GL/ PF5 MOE < 100 4a Wettable Powders: Aerial 1 2 (Wheat/ corn) 5 (stone fruit) 2 (vegetables) 1200 350 350 40 80 55 137 All MOEs < 100 MOE < 100 EC 4b Wettable Powders: Airblast 16 (Citrus 24C in California) 1.1 7.5 (Citrus, nuts, grapes, pome & stone fruit) 40 40 150 320 2180 EC EC Table 21: Summary of Short/ Intermediate Term Occupational Handler Noncancer Risks Scenario Rate (lb ai/ acre)

[unless noted] Area Treated (acres/ day)

[unless noted] Risk Summary MOEs Min. Req. PPE 87 4c Wettable Powders: Groundboom 1.5 2 (wheat/ corn) 2 (strawberries) 4 8 (turf/ golf courses) 200 80 40 240 320 599 299 599 EC EC EC 4d Wettable Powders: High Press HW/ ROW Sprayer 4 lb ai/ 100 gal (poultry) 1000 gal 102 SL/ GL/ PF5 4e Wettable Powders: Low press./ High Vol. Turfgun 4 (LCO on turf) 8 (LCO on turf) 5 5 102 205 SL/ GL/ PF5 SL/ GL/ PF5 4f Wettable Powders: Wide area aerial 2 (Range/ Forestry) 7500 6 MOE< 100 Applicators 5a Aerial: Agricultural uses, liquid sprays 1 1.5 (wheat/ avg. corn) 2 (max corn) 5 (stone fruit) 2 (vegetables, 24C on oysters) 1200 1200 350 350 113 170 85 116 292 EC MOE< 100 EC EC 5b Aerial: Wide area uses, liquid sprays 2 (Range/ Forestry) 0.016 0.15 (Mosquito adulticide) 1 (Mosquito adulticide) 7500 7500 7500 14 181 1700 27 MOE< 100 EC MOE< 100 5c Aerial: Agricultural uses, granular applications 2 (corn) 2 (corn) 1200 350 21 72 MOE< 100 MOE< 100 6a Airblast: Agricultural uses 16 (Citrus 24C in California) 2 7.5 (Citrus, nuts, grapes, pome & max. stone fruit) 1.1 (avg. stone fruit) 40 40 40 105 224 841 123 EC EC SL/ GL/ PF5 6b Airblast: Wide area uses, liquid sprays 0.016 (Mosquito adulticide) 0.15 (Mosquito adulticide) 1 (Mosquito adulticide) 3000 3000 3000 113 150 22 SL/ GL/ PF5 EC MOE< 100 7 Groundboom 1.5 2 (Wheat, corn) 2 (Strawberries) 4 8 (Turf/ golf course) 200 80 40 122 162 304 152 304 Baseline Baseline Baseline 8 Solid broadcast spreader (granular) 1. 5 2 (Wheat, corn) 2 (Strawberries) 4 8 (Turf/ golf course) 200 80 40 103 138 258 115 172 Baseline Baseline Baseline 9 Aerosol Can 0. 01 lb ai/ can 2 cans 324 Baseline 10 Trigger pump sprayer 0. 01 lb ai/ can 1 can 8772 SL/ GL/ NR 11 Right of way sprayer 1. 5 lb ai/ 100 gallons 1000 gallons 199 SL/ GL/ NR 12 High pressure handwand 4 lb ai/ 100 gallons 1000 gallons 66 MOE< 100 13 Animal groomer, liquid application 0. 01 lb ai/ dog 8 dogs 9.7 MOE< 100 14 Animal groomer, dust application 0.2 lb ai/ dog 8 dogs 8750 Baseline (dermal exp only)

15 Granulars & baits applied by hand 9 (Ornamentals & gardens) 1 3.8 MOE< 100 16 Granulars & baits applied by spoon 9 (Ornamentals & garderns) 1 75.1 MOE< 100 Table 21: Summary of Short/ Intermediate Term Occupational Handler Noncancer Risks Scenario Rate (lb ai/ acre)

[unless noted] Area Treated (acres/ day)

[unless noted] Risk Summary MOEs Min. Req. PPE 88 Mixerr/ Loader/ Applicators 17 Low pressure, high volume turfgun (ORETF Data) 8 (LCO Use on turf) 4 (LCO Use on turf) 5 5 94 104 MOE< 100 SL/ GL/ PF5 18a Wettable powder, low pressure handwand 1 lb ai/ 1000 ft 2 (poultry house) 2% solution (ornamentals) 20,000 ft 2 40 gallons 8.3 135 MOE< 100 SL/ GL/ PF5 18b Liquids, low pressure handwand 1 lb ai/ 1000 ft 2 (poultry house) 2% solution (ornamentals) 20,000 ft 2 40 gallons 127 1699 SL/ GL/ PF5 SL/ GL/ NR 19 Backpack sprayer 1 lb ai/ 1000 ft 2 (poultry house) 2% solution (ornamentals) 20,000 ft 2 40 gallons 42 565 MOE< 100 Baseline 20 Granular, bellygrinder 9 (Turf) 1 27 MOE< 100 21 Granular, push type spreader 9 (Turf) 5 124 SL/ GL/ PF5 22 Handheld fogger No data No data No data No data 23 Power backpack No data No data No data No data 24 Granular, backpack 9 (Ornamentals) 1 1562 DL/ GL/ NR 25 Tree injection No data No data No data No data 26 Drench/ dipping forestry/ ornamentals 1.5 lb ai/ 100 gallons (Ornamental/ seedling dip) 100 gallons 199 SL/ GL/ NR 27 Sprinkler can 2% solution (Ornamentals) 10 gallons 226 Baseline Flaggers 28a Flagger: liquid sprays 2 (Corn) 2 (Vegetables) 1200 350 249 111 EC Baseline 28b Flagger: granular applications 2 (Corn) 2 (Vegetables) 1200 350 101 345 Baseline Baseline Baseline = Long pants, long sleeved shirts, no gloves SL = Single layer clothing with or without gloves (GL or NG) DL = Double layer clothing (i. e., coveralls over SL) with or without gloves (GL or NG) EC = Engineering controls NR = No respirator PF5 = Protection factor 5 respirator PF10 = Protection factor 10 respirator Current label = SL/ GL/ NR Min. Req. PPE = level of PPE where MOEs > 100, where current label is exceeded or no adequate PPE is found, results are bold. MOEs which never exceed 100 are for highest feasible type of mitigation (e. g., engineering control in most cases). 89 Chronic Risks: MOEs were calculated for only a limited number of exposure ornamental use scenarios where the Agency believes that this kind of exposure pattern may exist. These calculations were also completed at different levels of personal protection as illustrated in Table 22. For most scenarios (3 of 5), MOEs meet or exceed the required uncertainty factor of 300 at some level of personal protection. The granular hand application scenarios are problematic. The uncertainty factor of 300 is required for the chronic exposure scenarios because a LOAEL and not a NOAEL was used for risk assessment.