UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D. C. 20460 OFFICE OF PREVENTION, PESTICIDES AND TOXIC SUBSTANCES MEMORANDUM SUBJECT: Worker Exposure Study Review: Assessment of Potential Inhalation and Dermal Exposure Associated with Pressure Treatment of Wood with Arsenical Products, Submitted September 24, 2001 by the American Chemistry Council's Arsenical Wood Preservatives Task Force.

TO: Connie Welch, Chief Adam Heyward, Product Manager, Team 34 Bonaventure Akinlosotu, Reregistration Team 36 Regulatory Management Branch II Antimicrobials Division ( 7510C)

FROM: Doreen Aviado, Biologist Team Two Risk Assessment and Science Support Branch ( RASSB) Antimicrobials Division ( 7510C)

THRU: Nader Elkassabany, Team Leader Team Two Risk Assessment and Science Support Branch ( RASSB) Antimicrobials Division ( 7510C)

Norm Cook, Chief Risk Assessment and Science Support Branch ( RASSB) Antimicrobials Division ( 7510C)

DP Barcode: D278302 ( S604391)

Pesticide Chemical Arsenic Acid/ 006801 Name/ No.: Chromated Copper Arsenate ( CCA)/ 128977 Reregistration Case/ No.: Chromated Arsenicals/ 0132 MRID No.: 455021 01 1 INTRODUCTION:

A primary review was conducted by contractor staff at Versar, Inc. on a study submitted September 24, 2001 by the Arsenical Wood Preservatives Task Force of the American Chemistry Council ( ACC) in support of reregistration data requirements for Chromated Copper Arsenate ( CCA) and related chromated arsenicals. The study entitled Assessment of Potential Inhalation and Dermal Exposure Associated with Pressure Treatment of Wood with Arsenical Products is further identified as follows:

Title Formulation, Active Ingredient Identifying Codes Corporate Sponsor Performing Laboratory Assessment of Potential Inhalation and Dermal Exposure Associated with Pressure Treatment of Wood with Arsenical Products Womanac ® Concentrate 60% CCA C used at Test Site A Timber Specialties K 33   ( C 60) CCA used at Test Site B Chemonite Part A, B and C were used to prepared ACZA MRID No. 455021 01; AASI Study No. AA9903089 Enviro Bio Tech Project No. AS 01 99 Arsenical Wood Preservatives Task Force Hasmukh C. Shah, Ph. D. American Chemistry Council 1300 Wilson Blvd. Arlington, VA 22209 Field Mark G. Bookbinder, Ph. D. ( Field Investigator) 11157 Yellow Leaf Way Germantown, MD 20876 1377 Phone/ FAX: ( 301) 540 5622 Analytical Harpal Singh, Ph. D. Enviro Bio Tech Ltd. 140 Shartlesville Road Bernville, PA 19506 The contractor review focused on evaluating the study for compliance with the Series 875  Occupational and Residential Exposure Test Guidelines; the ACC's study data addresses application exposure monitoring data guidelines 875.1100 Dermal Exposure Outdoor/ 875.1200 Dermal Exposure Indoor, and 875.1300 Inhalation Exposure Outdoor/ 875.1400 Inhalation Exposure Indoor. Included in the review is a " Checklist for Applicator Monitoring Data" addressing the major points used in evaluating the study's compliance with Series 875. AD/ RASSB reviewed ACC's submission and conducted a secondary review of the contractor findings. A detailed study review is presented herein which presents an overview of the study procedures and resulting data, and assesses the technical merits of the data as a source of exposure information for developing the occupational exposure estimates for the Chromated Copper Arsenate ( CCA) RED.

EXECUTIVE SUMMARY:

This study assessed the potential dermal/ inhalation exposures of pressure treatment plant employees involved in the production of treated wood products. This study was designed to estimate individual worker exposure to Chromated Copper Arsenate ( CCA) Type C and Ammoniacal Copper Zinc Arsenate ( ACZA) compounds while performing the typical job functions involved in commercial arsenical pressure treatment of lumber at three commercial treatment facilities located in the United States and Canada ( referred to as Sites A through C). Four end use products for CCA and ACZA were used. Sixty four workers performing 26 job functions ( tasks) were monitored for each 8 hour shift. Many of the job functions were performed by one or more worker( s) in a variety of indoor/ outdoor work settings. These job functions fell within up to eight job categories across the three test sites. Where a single worker 2 performed the duties of more than one job function, he or she was identified by the title of the job function which represented the majority of their work efforts.

Both dermal and inhalation exposure levels were estimated for monitored workers. The dermal exposure levels were estimated by passive dosimetry using whole body dosimeters ( WBDs) and cloth dosimeter gloves worn under the workers' protective clothing and chemical resistant gloves. The inhalation exposure levels were estimated by active dosimetry using a sampling train placed in the worker's breathing zone which collected residues onto a PVC filter cassette. The air was pulled through the sampling train by a portable air sampling pump.

In lieu of applying known quantities of a characterized metal oxide formulation to each charge of wood products, study personnel collected data generated by the application system for each treatment made during the monitored period at each test site. This information was not however used to calculate an inhalation or dermal unit exposure ( e. g., usually measured in mg/ lb ai handled). According to the study, the major source of CCA or ACZA for worker exposure in these types of facilities is preservative remaining on or escaping from treated wood or equipment that had been in a cylinder during treatment. This is presumably a very small fraction of the quantity actually applied to and retained by the charge.

The components of CCA or ACZA ( e. g., arsenic, chromium, copper, or zinc) for each WBD segment and glove pair from each worker was corrected based on the mean field fortification recovery of the appropriate analytical standard( s) from samples fortified in the field at that test site. WBD segments were also adjusted based on background. The analytical method was subject to some variability at levels near the LOQ, suggesting that recoveries obtained at that level were likely to be less reliable than those at the higher level. The registrant did not make any corrections to the raw data when field fortification recoveries were > 100%.

Each calculated exposure level was normalized to an exposure dose expressed in

g/ kg worker body weight/ day. The exposure dose was normalized using the U. S. EPA recommended mean adult weight of 71.8 kg and a standard work day of 8 hours/ day. The " total" dermal exposure for each replicate for each worker was calculated by summing the normalized residue levels in his WBD arms, WBD top, WBD bottom ( torso portion and legs, cut apart at EN CAS and analyzed as separate samples), and all glove dosimeters worn during that replicate.

Geometric mean dermal exposures across all job functions at all of the three sites ranged from 2.91 to 98

g/ kg bw/ day and from 1.49 to 4.74

g/ kg bw/ day for arsenic and chromium VI, respectively. Total chromium, copper, and zinc levels were also reported. The highest individual CCA/ ACZA components ( e. g., arsenic, chromium total, chromium VI, copper and zinc) were found for the Tram Setter. Exposure levels for the Treatment Operator and Loader Operator at Site B ( which used the smallest amount of arsenic, copper and chromium) were notably higher than those calculated for the same positions at the other two sites. Within each job class monitored, and over all classes at each site, those individuals whose activities involved the greatest proximity to CCA/ ACZA component sources were exposed to the highest levels of CCA/ ACZA.

Calculated inhalation exposure levels were normalized by scaling up the pump flow rate of 1 L/ min to the U. S. EPA recommended minute ventilation rate of 1100 L/ hr ( approximately 18.34 3 L/ min) for " light activities", and then adjusting for the standard EPA recommended adult weight of 71.8 kg. Geometric mean inhalation exposures across all of the job functions at all three sites ranged from 0.044 to 0.256 ( As)

g/ kg bw/ day for arsenic and 0.033 to 0.042

g/ kg VI bw/ day for Chromium. The Tram Setter and the Supervisor were the highest exposed individuals. Within each job class monitored, and over all classes at each site, those individuals whose activities involved the greatest proximity to CCA/ ACZA component sources were exposed to the highest levels of CCA/ ACZA. According to the Study Report, due to the fact that none of the workers monitored in this study performed continuous light activity, the use of the recommended ventilation rate probably resulted in a notable over estimation of inhalation exposure. The fact that values were generated even for those compounds that were never detected or quantifiable in field samples contributes to the over estimation of inhalation exposures as well.

The assessment for this study focused on Series 875 compliance and issues of technical merit. Based upon the review, this study does meet most of the Series 875 guideline requirements ( the method validation, field spikes, and QA/ QC were thoroughly explained); however, some minor issues are as follows:( 1) data were not reported as unit exposures ( e. g., mg/ lb ai) therefore differences in CCA/ ACZA chemical usage, versus exposure between facilities were not examined thoroughly; ( 2) data were corrected based on field recovery; however, only the corrected data were presented in the study and the corrections calculations were not expressed; and ( 3) separate field fortification samples were not collected for each worker job function; only triplicate field fortification samples were collected at each site.

In spite of these deficiencies, the Agency considers these data as acceptable in satisfying the application exposure data guideline requirements under Series 875 for both dermal and inhalation exposure monitoring ( guidelines 875.1100/ 875.1200 for dermal and 875.1300/ 875.1400 for inhalation) and recommends use of these data, where appropriate, in developing the occupational exposure estimates for certain handler scenarios in the CCA RED human exposure chapter. It is also recommended that data from monitored workers involved with tasks that are done after the wood has been pressure treated ( e. g., data for Test Borer and Stacker Operator functions) be used in estimating certain post application exposure doses.

STUDY OVERVIEW:

Background Three commercial facilities in the U. S. and Canada were used in this study to determine the dermal and inhalation exposure of workers applying CCA and ACZA end use products to dimensional lumber, outdoor furniture components, utility poles and/ or posts by pressure treatment systems. Two of the facilities ( referred to herein as Sites A and B) were located in the U. S. ( Orangeburg, South Carolina; and Eugene, Oregon). The third facility ( referred to herein as Site C) was located in Delson, Quebec, Canada. The three facilities and the end use products used in this study were said to represent a range of geographic locations, formulations used, species of wood products treated, and application parameters used for treatment of wood with CCA.

At each site, pressure treatment of wood products was performed using the same basic process. Workers operated self propelled or stationary loaders which moved untreated poles or 4 dimensional lumber from holding areas and stacked them onto wheeled metal trams on a railroad track leading into the treatment cylinder( s). When enough trams were loaded to fill a cylinder, the poles or ties on each tram were tied together with chains of metal or plastic bands. A charge cable ( or " lead cable") was connected to the tram load of wood products farthest from the cylinder door, and was laid along the top of the stacked items on the trams. The filled trams made up a " charge" of wood products.

The cylinder door was opened either hydraulically or manually and its drawbridge was positioned so that it connected the drip pad track with the cylinder's interior rails. The charge was then pushed into the cylinder by a self propelled loader or a self pulled into the cylinder by an automated transfer deck. Workers placed the free end of the lead cable into the cylinder, closed the cylinder door( s), and started the treatment process. Treating solution was then pumped from storage tanks into the cylinder, after which pressure ( 120  180 psi) was applied to the cylinder to allow the preservative to permeate the wood of the poles. CCA solutions were used unheated, while ACZA solutions were heated to 120 140  F during treatment.

After treatment, excess treating solution was removed from the cylinders and wood products by maintaining a vacuum in the cylinder for approximately 1 to 5 hours. The duration of a treatment cycle ranged from approximately 2 to 340 hours, depending on the species of wood treated, the procedures used by each site, and whether CCA or ACZA was being used. At the end of treatment, the cylinder was opened, and a mist containing water and some preservative was observed.

Workers removed the charge from the cylinder by removing the end of the lead cable from the cylinder and attached it to a hook on a self propelled loader, which then pulled the loaded trams out of the cylinder. At Sites A, B, and C, each charge was pulled onto a concrete " drip pad," where excess treatment solution was allowed to drip from the wood products and trams onto the pad for up to several hours. After site personnel removed lead cables and chains, the cooled poles were pushed by the loader to a storage area, where workers using hand or electric powered drills took narrow cores of wood from selected poles or ties to determine the depth of penetration of the preservative, and the amount of preservative that was actually absorbed by the wood. Charges that did not contain enough CCA or did not penetrate deep enough were retreated as above.

Sixteen workers were monitored for this study for 4 5 consecutive work days each. On each day of monitoring, one or more loads of dried, debarked poles or posts, or cut dimensional lumber or other wood products were stacked on moveable trams, and pushed into horizontal cylinders. Each cylinder was filled with a mixture containing arsenic pentoxide, copper oxide, and either chromium oxide or zinc oxide wood. The treated wood absorbed between approximately 41 lbs and 1,011 lbs of total metal oxides per charge, depending on the charge volume and treatment parameters.

The treatment plant job categories monitored in this study include treatment operators, treating assistants, loader operators, test borers, tram setter, tally man, and stacker operator. Workers performed typical tasks related to these activities and were monitored for up to 4 5 consecutive work days each. Descriptions of the tasks monitored are bulleted below : 5 ° Treatment Operators ( TOs)  At Sites A, B, and C, the TOs operated and monitored application system valves and controls; they sometimes opened and closed cylinder doors, and they supervised the insertion and removal of charges ( loads of dried, debarked poles or untreated ties) of poles from the treatment cylinders.

° Treating Assistant ( TA)  At Sites A, and C, the TAs performed many of the same functions as the TOs and sometimes assisted the TO in charge preparation, cylinder cleaning and maintenance, filter cleaning, mixing of treatment solution, and also participated in some loader operations moving charges.

° Loader Operators ( CLOs in the cylinder area, and LLOs in the load out areas)  At Sites A, B, and C, the LOs stacked untreated wood onto charge trams, moved charges into and out of treatment cylinders, distribute treated wood to load out area, and loaded treated wood for shipment. One Site B Supervisor ( S) performed mainly LO tasks.

° Test Borers ( TBs)  At Site C the TBs cut cores from freshly treated poles or ties for testing for CCA preservative penetration/ retention. At the other sites this function was performed by TO/ TA/ LO personnel.

° Tram Setter ( TS) At Site A the TS steam cleaned drip pads and tracks, Operated cylinder door controls, cleaned cylinders, handled hazardous waste, and manually moved trams and placed drawbridges for treatments.

° Stacker Operator ( SO) At Site A the SO operated a lumber stacking device which arranged treated boards in stacks for banding and shipment. Worker manually positioned ends of boards being fed into device.

° Tally Man ( TM) At Site C the TM primarily counted and inspected incoming and outgoing truckloads of wood products and supervised loading/ unloading of lumber trucks at the drip pad and adjacent locations.

Dermal exposure levels were estimated by passive dosimetry using whole body dosimeters ( WBD) worn under the worker's clothing and lightweight cotton glove dosimeters worn under work gloves. The dermal exposure levels to CCA and ACZA were estimated by measuring the levels of arsenic, chromium, copper, and zinc compounds. Each analyte was determined in all WBD and glove samples.

Inhalation exposures for each worker were estimated by active dosimetry. Each worker wore a sampling train consisting of a 37mm polyvinyl chloride ( PVC) filter in a plastic cassette, attached to the front of the work shirt with the intake orifice in the breathing zone. The intake orifice was oriented downward and connected by Tygon ® tubing to a second cassette, attached to a Buck S. S. Pump on the work belt. The pump drew air through the sampling filter at approximately 2 L/ min while the subject performed the tasks. Pumps were calibrated immediately prior to and after each monitoring period using a NIST traceable calibrated Sierra ® Top Trak   mass flow meter.

STUDY PROCEDURES: 6 Mixing/ Loading/ Application Method Pressure treatment operations were conducted at three sites ( Sites A C). At Site A, pressure treatment operations were conducted in a fully enclosed Treatment Control Room ( TCR) which includes a computerized system ( built and provided by the plant's CCA supplier) for operating and monitoring all aspects of pressure treatment. CCA concentrate was delivered to the plant by truck, and unloaded ( by the truck driver, using a closed transfer system) into a storage tank at a covered tank farm. All treating system control valves were operated automatically from a workstation.

At site B, CCA concentrate and polyethylene glycol concentrate ( PEG) were delivered to the plant by truck. Deliveries were handled by the truck drivers, using a completely closed system, and did not involve plant personnel, except for power washing drip pads before the truck arrives. The treatment control room, tank farm, and portions of the water recovery system for the cylinders were located in the cylinder room. Each cylinder's treatment system was controlled from a bank of switches located alongside the cylinder. These switches were operated manuallythere is no computer control of the treatment system or transfer deck.

At Site C, ACZA treatment solution was used. The ACZA mixing area was directly to the west of the treatment building. It includes a warehouse for storage of the dry ingredients used to prepare the application solution, and an adjacent tank farm. A small adjacent area was used to store drums of powdered copper oxide. Separate tanks were used to: ( 1) store arsenic acid arsenic acid solution ( delivered by tank truck and transferred using a closed system), ( 2) mix the ACZA concentrate, and ( 3) store the mixed concentrate.

In lieu of applying known quantities of a characterized metal oxide formulation to each charge of wood products, study personnel collected data generated by the application system for each treatment made during the monitored period at each test site. These commercial records were not made for each cycle during the monitored period at each test site. The treatment parameters for each charge inserted or removed from a cylinder, or in process during monitored work cycles are presented in Table 1. A detailed description of the type of wood treated, amount of oxides in solution, and duration of the treatments is presented in pages 88 90 of the Study Report ( MRID No. 455021 01).

Table 1. Application of Test Substances Test Site Test Days No. Charges Monitored Total cu ft of Wood Treated Total lbs Oxides Used As Cu Cr Zn Mean Charge Duration A 5 34 39,702 13,426 5,008 2,667 6,993  01: 54 B 5 16 28,191 5,363 1,802 944 2,620  02: 51 C 5 7 7,948 2,928 772 1,433  723 23: 07 Exposure Monitoring 7 Dermal The CCA dermal exposure to each worker was determined using a whole body dosimeter ( WBD), consisting of a 100% polyester thermal shirt and long pants. All worker at Sites A, B, and C wore their WBD under a fresh work uniform consisting of a cotton long sleeved work shirt and cotton work trousers ( or one piece cotton coverall) provided by the test site. The workers at Site B wore a cotton long sleeved work shirt and cotton work trousers provided by the test site Each worker at all four sites wore a lightweight 100% cotton glove dosimeter on each hand, under his chemical resistant or work gloves, as appropriate.

At the beginning of each work cycle ( or 8 hour shift), the workers washed their hands with detergent and water, put on the WBD, followed by a fresh uniform and other work clothes. Once the worker was ready to start the work cycle, study personnel placed the glove dosimeters on the hands. At the end of the work day, study personnel removed the worker's glove dosimeters, placed the pair in a locking polyethylene storage bag and froze them on dry ice. When the break ended, the worker put on a fresh pair of glove dosimeters. At the end of the work day, study personnel collected the worker's glove dosimeters and handled them as noted above. The study personnel helped each worker remove the outer work clothes and then cut the WBD in sections, including paired arms, remainder of shirt (" torso top"), briefs and paired legs. Each section was packaged as described above, labeled, and placed on dry ice for shipment to Enviro Bio Tech, Ltd. ( EBT).

Inhalation Inhalation exposures for each worker was estimated by active dosimetry. Each worker wore a sampling train consisting of a 37 mm polyvinyl chloride ( PVC) filter in a plastic cassette, attached to the front of the work shirt with the intake orifice in the breathing zone. The orifice was oriented downward, connected by Tygon ® tubing to a second cassette, attached to a Buck S. S. Pump on the work belt. The pump drew air through the sampling filter at approximately 2 L/ min while the subject performed the tasks. Pumps were calibrated immediately prior to and after each monitoring period using an NIST traceable calibrated Sierra ® Top Trak   mass flow meter. The pumps were turned on at the beginning of each work cycle and was left running during restroom, coffee, or other short breaks. They were turned off or set on " hold" during lunch breaks. The pumps and samplers were removed from the workers during the lunch break. At the conclusion of the lunch break, the pump and sampling train were reinstalled and the pump was restarted. All start and stop times were recorded.

Analytical Methods Dermal Recovery testing of residues of CCA and ACZA components in dermal exposure monitoring matrices were determined using Standard Operating Procedure 288.01 For The Determination of Copper, Arsenic, Chromium, and Zinc in PVC filters, Gloves, and Work Clothes By Atomic Absorption Spectrophotometry, Dated 12/ 2/ 99. For this procedure, a dermal sample was placed into glass jar ( size of jar was dependant upon the size of the sample). For each WBD section, 890 mL of 0.05M ( NH 4) 2 SO 4/ 0.05M NH 4 OH extraction solvent was 8 added to the sample jar. The jar was then sonicated for 20 minutes and shaken mechanically for 60 minutes. A 10 mL aliquot of the extract was removed for determination of Cr+ 6, and the remaining sample was acidified by addition of 50 mL of concentrated HNO 3 and shaken for another 90 minutes.

For each pair of gloves, 190 mL of 0.05M ( NH 4) 2 SO 4/ 0.05M NH 4 OH extraction solvent was added to the sample jar. The jar was then sonicated for 15 minutes and shaken mechanically for 30 minutes. A 10 mL aliquot of the extract was removed for determination of Cr+ 6, and the remaining sample was acidified by addition of 15 mL of concentrated HNO 3 and shaken for another 90 minutes.

For each filter, 20 mL of 0.05M ( NH 4) 2 SO 4/ 0.05M NH 4 OH extraction solvent was added to the sample jar. The jar was then sonicated for 10 minutes and shaken mechanically for 30 minutes. A 5 mL aliquot of the extract was removed for determination of Cr+ 6, and the remaining sample was acidified by addition of 1 mL of 70% aqueous HNO 3 and shaken for another 30 minutes.

Cr+ 6 was determined separately from other compounds using different methods. Cr+ 6 was determined colorimetrically in the alkaline extract of each sample. A 3 mL aliquot was passed through a solid phase extraction ( SPE) cartridge that has been preconditioned with 2 mL of methanol followed by 3 mL of de ionized water. The flow rate was 2 mL/ minute under slight vacuum. The cartridge was rinsed with 3 mL water and Cr+ 6 was eluted with 9 mL of 0.5M ( NH 4) 2 SO 4/ 0.1 M NH 4 OH buffer in three 3 mL aliquots. The eluate was acidified with 100 µ L of 37% aqueous HCL. Two mL of a solution of 250 mg of 1,5 diphenylcarbazide in 50 mL acetone was added, and the solution was mixed and allowed to stand for 10 minutes for maximum color development. An aliquot was transferred to a 1 cm cell, and its absorbance was determined in a Milton Roy Spectronic 501 Spectrophotometer.

The limit of quantitation ( LOQ) for Cr+ 6 for each monitoring matrix and the calculated corresponding limit of detection ( LOD) was as follows in

g of analyte per sample:

LOD LOQ S Gloves 10 30 S Airfilter 0.5 1.5 S WBD Part 50 150 Determination of total metals ( total arsenic, copper, chromium, and zinc) in the acidified extract of each sample was performed by atomic absorption spectrophotometry per EBT SOP 288.01. A small aliquot of each extract was transferred to a glass tube and inspected visually. If any suspended material was visible, the sample was centrifuged for about 5 minutes at ~ 2,000 rpm. An aliquot of each extract was transferred to a 2.5 mL autosampler vial using a disposable Pasteur pipette, along with an appropriate quantity of matrix modifer:

° For Cr analysis: One mL of a solution of 11.8 g. Ca( NO 3) 2 * 4H 2 O diluted to 100 mL with HPLC grade water was added to every 100 mL of sample to be analyzed.

° For As determination: One mL of a solution of 1% nickel nitrate in HPLC grade water was added to 9 mL of sample to be analyzed. 9 ° For Cu analysis: no matrix modifier was required.

For As, Cr, or Cu determination, a 20 µ L aliquot of the mixture was analyzed by atomic absorption spectrophotometry, using a Buck Scientific Model 210VGP AA Spectrophotometer with a Buck Model 220GF Graphite Furnace and a Buck Model 220AS Autosampler. The following monochromator wavelengths were used: 193.7 nm ( for As), 357.9 nm ( for Cr), 324.7 nm ( for Cu), and 213.9 nm ( for Zn).

For Zn determination, a 20 µ L aliquot of the extract was analyzed by direct aspiration AA using a Buck Scientific Model 200 A Spectrophotometer, with the monochromator set at 213.9 nm. Sample absorbance was recorded while the sample was aspirated into the flame. Absorbance data for initial sample sets were automatically printed out by the equipment.

The limits of quantitation ( LOQ) determined for each target analyte in/ on each matrix analyzed by this method ( and the limits of detection calculated for each) are shown below:

LOD LOQ Analyte Matrix (

g/ sample) (

g/ sample)

As Glove pair 2.50 7.50 Filter 0.500 1.50 WBD section 16.0 48.0 Cu Glove pair 2.50 7.50 Filter 0.500 1.50 WBD section 16.0 48.0 Total Glove pair 2.00 6.00 Cr Filter 0.250 0.750 WBD section 5.00 15.0 Zn Glove pair 3.75 7.5 Filter 0.50 1.50 WBD section 16.0 48.0 STUDY RESULTS:

Method Validation Pre field recovery tests were performed at the AASI Field Research Facility at Lucama, NC in order to determine the recovery of metals applied to exposure monitoring matrices. Sets of triplicate samples of WBD sections, paired glove dosimeters and single PVC air filters were fortified with reference standard metal ions or reference standard hexavalent chromium, at LOQ, 10 x LOQ, 100 x LOQ, and at the control. Samples were set on tables and exposed to ambient conditions for 8 hours, to simulate field sampling conditions. Air sampling trains were run during the exposure period at a flow rate of 2 L/ min. At the end of the exposure period, each WBD and filter cassette sample was placed in a labeled locking polyethylene storage bag, and placed on dry ice for shipment to EBT. Glove bottles were capped, labeled, sealed, and placed on dry ice. The method validation results are summarized below in Table 2. 10 Table 2. Method Validation Results for CCA in WBD Sections, Glove Pairs, and Filters Analyte Matrix Spike Level (

g) % Recovery Mean S. D. % cv Cr+ 6 WBD 150 15,000 92.8 ( n= 7) 4.91 5.29 Gloves 30 3,000 97.2 ( n= 7) 1.89 1.94 Filters 1.5 150 96.8 ( n= 7) 3.31 3.42 Total Cr WBD 15 1,500 94.9 ( n= 7) 11.9 12.5 Gloves 6 600 89.6 ( n= 7) 6.66 7.44 Filters 0.75 75 107 ( n= 7) 6.57 6.14 Total Cu WBD 48 4,800 96.8 ( n= 7) 7.70 7.95 Gloves 7.5 750 87.5 ( n= 7) 12.4 14.1 Filters 1.5 150 103 ( n= 7) 8.57 8.36 Total As WBD 48 4800 101 ( n= 7) 9.38 9.26 Gloves 7.5 750 100 ( n= 7) 9.00 8.99 Filters 1.5 150 103 ( n= 7) 6.48 6.30 Total Zn WBD 48 4800 106 ( n= 7) 7.61 7.19 Gloves 7.5 750 106 ( n= 7) 9.14 8.62 Filters 1.5 150 95.4 ( n= 7) 14.5 15.2 Breakthrough/ Retention Testing Breakthrough/ retention testing was performed in order to insure that CCA components would not migrate from one to the other cassette. Mean percent recovery of metals from the front filters were as follows: 113%  total Cr; 94%  Cr+ 6; 103%  Cu; 114%  As; and 94%  Zn. All control recoveries for all analytes from the rear filters were below the LOQ for this test. The results demonstrate that all analytes were retained in the fortified filters and breakthrough did not occur.

Pre field Recovery of CCA in Whole Body Dosimeters, Gloves and Filters A pre field recovery study of CCA in whole body dosimeters ( WBD), gloves and filters was performed in order to determine that CCA applied to these matrices would be retained during field sampling and transport. The mean percent recoveries showed some loss of Cr+ 6 on WBD ( 73.1%) and gloves ( 66.2%) and loss of total Cr to gloves ( 78%) during exposure to ambient conditions. For the other samples ( including total Cr, Cu, As, and Zn) the recovery ranged from 88 Percent to 112 Percent.

Laboratory Spikes Laboratory fortified samples of each matrix used in the study were analyzed concurrently with 11 field samples to monitor procedural recoveries. The mean recovery of total arsenic, chromium, chromium VI, copper, and zinc from laboratory fortified glove and WBD samples is summarized in Table 3. The mean recoveries laboratory spike recoveries were well within the acceptable range.

Field Spikes Samples of exposure monitoring matrices were shipped on dry ice, as soon as possible after collection, by overnight courier to EBT's facility in Bernville, PA. Samples were stored at room temperature prior to analysis. Control samples included all sampling media, i. e., gloves in pairs, single air filters, and representative WBD sections ( single torso top fronts or backs, single bottoms, single arms or legs). Field Fortification recoveries are shown in Table 4.

Field fortification samples were prepared once at each facility. Unexposed WBD sections, paired glove dosimeters, single air sampling filters, and complete air sampling trains were fortified in the field to assess potential degradation or reduced extractability of residues due to exposure to environmental conditions, handling, packaging, shipping, and frozen storage.

Dermal Field Fortification Samples On at least one day of monitoring, two sets of 12 samples of each matrix was randomly selected from those being used for worker monitoring. In each set, three of each matrix were blank controls, and three were fortified (" spiked") with a solution of standard As, Cu, Zn, Cr, or Cr+ 6 at each of two levels, LOQ, and 100xLOQ.

Inhalation Field Fortification Samples On each day of fortification, two sets of twelve samples of each matrix were randomly selected from those being used for worker monitoring. In each set, three of each matrix were blank controls, and three were fortified with a solution of standard As, Cu, Zn and total Cr or Cr6+ at each of two levels LOQ and 100x LOQ. A fresh spike solution were used for each spike day. The air samplers will be attached to calibrated air pumps running at the rate established for field sampling. 12 Table 3. Recovery of Total CCA/ ACZA from Laboratory Fortified WBD Sections, Glove Pairs, and Filters Analyte Test Site Matrix Spike Level (

g) % Recovery Mean S. D. % cv Cr+ 6 A WBD 240 4800 90.8( n= 26) 4.55 5 B WBD 48 4800 90.4 ( n= 19) 5.39 6 A Gloves 7.5 750 87.3 ( n= 10) 6.45 7.4 B Gloves 7.5 6000 89.7 ( n= 17) 6.71 7.5 A Filters 1.5 150 93.7 ( n= 5) 3.41 3.6 B Filters 1.5 150 91.2 ( n= 8) 4.99 5.5 Total Cr A WBD 150 15000 92.4 ( n= 26) 11.1 12 B WBD 165 16500 100 ( n= 19) 5.93 5.9 A Gloves 30 3000 92.6 ( n= 10) 11.1 12 B Gloves 36 3600 101 ( n= 17) 15.4 15.2 A Filters 1.5 150 93.9 ( n= 5) 7.68 8.2 B Filters 2.3 225 104 ( n= 8) 7.16 6.9 Total Cu A WBD 48 4800 86 ( n= 26) 11.79 13.7 B WBD 48 4800 94.5 ( n= 19) 11.2 11.9 C WBD 48 4800 93.9 ( n= 26) 6.61 7.0 A Gloves 7.5 750 98.3 ( n= 10) 10.8 11 B Gloves 7.5 753 97.3 ( n= 17) 11.4 11.7 C Gloves 7.5 750 95.3 ( n= 16) 11.0 11.5 A Filters 1.5 150 103 ( n= 5) 9.38 9.1 B Filters 1.5 150 106 ( n= 8) 12.3 11.6 C Filters 1.5 150 92.2 ( n= 9) 6.13 6.6 Total As A WBD 48 4800 86 ( n= 26) 9.38 10.9 B WBD 48 4800 94.5 ( n= 19) 11.2 11.9 C WBD 48 4800 103 ( n= 26) 6.24 6.1 A Gloves 7.5 750 102 ( n= 10) 8.88 8.7 B Gloves 7.5 750 97.3 ( n= 17) 13.27 13.6 C Gloves 7.5 750 95.3 ( n= 16) 6.61 6.9 A Filters 1.5 150 100 ( n= 5) 15.3 15.3 B Filters 1.5 150 95.7 ( n= 8) 6.62 6.9 C Filters 1.5 150 102 ( n= 9) 8.88 8.7 Total Zn C WBD 48 4800 98 ( n= 9) 12.8 13 C Gloves 7.5 750 103 ( n= 16) 4.78 4.6 C Filters 1.5 150 104 ( n= 26) 8.95 8.6 13 Table 4. Recovery of Total CCA/ ACZA from Field Fortified WBD Sections, Glove Pairs and Filters Analyte Test Site Matrix Spike Level (

g) % Recovery Mean S. D. % cv Cr+ 6 A WBD 750 15000 88.8( n= 18) 4.3 4.8 B WBD 750 15000 91.6( n= 30) 3.0 3.3 A Gloves 150 3000 76.7 ( n= 18) 5.9 7.7 B Gloves 150 3000 89.2 ( n= 30) 5.4 6.1 A Filters 7.5 150 91.4 ( n= 18) 3.5 3.8 B Filters 7.5 150 90.9 ( n= 30) 3.9 4.3 Total Cr A WBD 750 15000 93.0 ( n= 18) 10 10.8 B WBD 825 16500 95.7 ( n= 30) 6.4 6.7 A Gloves 150 3000 100 ( n= 17) 13.1 13.1 B Gloves 180 3598 95.9 ( n= 30) 11.9 12.4 A Filters 7.5 150 106.5 ( n= 18) 13.4 12.6 B Filters 11.3 225 113.3 ( n= 30) 6.6 5.8 Total Cu A WBD 240 4800 95.5 ( n= 12) 16.8 17.6 B WBD 240 4800 89 ( n= 30) 10.3 11.6 C WBD 240 4800 92.4 ( n= 30) 8.4 9.1 A Gloves 37.5 750 98.0 ( n= 17) 15.5 15.8 B Gloves 37.5 750 104 ( n= 30) 11.7 11.3 C Gloves 37.5 750 97.4 ( n= 24) 7.8 8 A Filters 7.5 150 95.8 ( n= 18) 19.7 20.6 B Filters 7.5 150 106.4 ( n= 30) 15.3 14.4 C Filters 7.5 150 92.4 8.4 9.1 Total As A WBD 240 4800 95.5 16.8 17.6 B WBD 240 4800 100.9 18.9 18.7 C WBD 240 4800 103.3 6.5 6.3 A Gloves 37.5 750 101.7 ( n= 17) 17 16.7 B Gloves 37.5 6000 98.8 ( n= 30) 10.8 10.9 C Gloves 37.5 5250 92.9 ( n= 24) 12.6 13.6 A Filters 7.5 150 109 ( n= 18) 12.7 11.7 B Filters 7.5 150 103( n= 30) 7.2 7.0 C Filters 7.5 150 107.9 ( n= 30) 7.7 7.1 Total Zn C WBD 240 4800 98.4 ( n= 30) 4.6 4.6 C Gloves 37.5 750 100.4 ( n= 24) 5.7 5.7 C Filters 7.5 150 95.4 ( n= 24) 5.4 5.7 14 Formulation Testing The field phase of this study was performed using lots of CCA or ACZA that were already onsite at the time the field study phase was conducted. Analysis and expiration dates were not provided for those commercial lots. Tank mixes were analyzed by on site QC personnel: copies of relevant analysis results are archived with the raw data from each test site. Study personnel collected at least one sample of each separate batch of CCA or ACZA used to treat lumber products during monitoring at each site. Each sample was placed in a polyethylene or glass container and stored on dry ice and shipped to EBT for archival storage. At least one sample was analyzed per test site.

Storage Stability The stability of arsenic, chromium, chromium ( VI), copper, and zinc was determined in WBD sections, glove pairs, and air filters and stored frozen (< 15  V) by EBT at several different fortification levels ( 1x or 10 x LOQ) for up to 20, 60, or 90 days prior to extraction. The results are summarized in Table 5. Residue levels declined by less than 5% for all media demonstrating that these materials were stable. It should be noted that target metal levels in field samples were adjusted for recoveries from field fortified controls that were collected, shipped, stored, extracted, and analyzed concurrently with those field samples, and thus incorporated any necessary adjustment for storage effects.

Table 5. Storage Stability Results Analyte Matrix Spike Level (

g) % Recovery 0 days 30 days 60 days 90 days Cr+ 6 WBD 480 4800 100 99.4 99.3 NA Gloves 30 3,000 96.8 100 100 NA Filters 1.5 150 100 99.4 99.3 NA Total Cr WBD 15 1500 101 99.3 113 96.3%

Gloves 7.5 750 101 106 108 NA Filters 0.75 75 102 97.2 107 NA Total Cu WBD 48 4800 97.9 108 102 111%

Gloves 7.5 777.25 103 116 100 NA Filters 1.5 150 99.8 92.2 101 NA Total As WBD 48 4800 98 100 102 94.9%

Gloves 7.5 750 105 100 99.1 NA Filters 1.5 150 98.2 97.6 98.2 NA Total Zn WBD 48 4800 102 102 104 102%

Gloves 7.5 750 99.4 102 98.6 NA Filters 1.5 150 100 100 98.5 NA 15 Exposures In lieu of applying known quantities of a characterized metal oxide formulation to each charge of wood products, study personnel collected data generated by the application system for each treatment made during the monitored period at each test site. These commercial records were not made during the monitored period at each test site. The treatment parameters for each charge inserted or removed from a cylinder, or in process during monitored work cycles were already presented in Table 1.

Dermal Results Dermal worker exposure were measured for each worker task identified in Section 3.1. It appears that workers placed in the closest proximity of exposure ( e. g., TS, TM, TO, LO) were exposed to the highest quantities of target analytes. During each replicate of monitoring, dermal exposure of the subject's body to ACZA/ CCA components was determined by collection of material in/ on the cotton WBD. Exposure of the hands was determined from material collected in/ on the cotton glove dosimeters ( worn under chemical resistant gloves, as appropriate).

Exposure levels for the TO and LO at site B which used the smallest amount of arsenic, copper and chromium were notably higher than those calculated for the same positions at the other two sites ( see page 66 in the Study Report). The differences may have been due to the following reasons: 1) an increased potential for exposure of each worker resulting from having fewer workers performing all treatment related tasks at this site, 2) the dispersal of target metals from the surfaces of treated wood into the drip pad area resulting from application of jets of pressurized water directed from the ring washer onto charges emerging from cylinders, 3) differences in treatment processing at this site, 4) the enclosed drip pad and the cylinder area are likely to retain some of these dispersed materials, increasing their availability for worker contact, and 5) the presence of open channels in the floor of the cylinder room and drip pad room for returning used treating solution and contaminated wash water to work tanks for reuse.

Overall exposures for the Site A TO were higher than those of the Site C TO. Copper exposures for the TA and LO at Site C were higher than those of their counterparts at Site A, as would be expected based on usage, roughly reflecting the relative level of use of the two metals at those facilities. However, arsenic exposures for those positions were similar in magnitude at both sites. Calculated levels of exposure to Cr6+ were far smaller than those calculated for Crtotal for all positions at Site A ( where calculated Cr6+ was 3.8 16.2% of Crtotal levels) and site B ( where calculated Cr6+ was 3.5 6.3% of Crtotal levels). These results demonstrate that much of the Cr6+ is reduced to Cr3+. Also it should bet noted that the calculated levels of Cr6+ are overestimates of actual levels, resulting from the effect of assigning values to nondetectable and nonquantifiable levels in samples.

Corrections to each WBD segment and glove pair were made for the mean recovery of the appropriate analytical standard from samples of the appropriate matrix fortified in the field on the same day or the spike day at the site with ambient conditions most similar to the monitoring day. Adjustments were made even when recoveries from field control samples were > 100%. The generally used convention for samples containing very low levels of analyte was applied: for any sample in which the level of any analyte was below its LOQ but above the LOD, ½ of the LOQ was used as an upper bound estimate of the residue in the sample for calculation of exposure to that analyte. In addition, for any sample where the level of any analyte was below the LOD, ½ of the LOD was used as the upper bound estimate for calculation of exposure to that analyte. 16 Exposure levels were also adjusted based on background levels. The background levels were identified based on pre test WBDs. Background testing was performed by wearing a fresh WBD at home under normal clothing, for approximately 8 hours during one non work day prior to participation in the study. Appendix D in the Study Report ( MRID No. 455021 01) presents WBD data that was corrected by subtracting raw data minus background data. Background data were obtained by measuring the residue on WBDs when a worker was at home. In some cases the background data was actually higher than the raw data therefore concentrations were listed as negative number ( e. g., Site A Job Class TA, Rep 1, Body Part Arms  1.82 µ g per 8 hour day). The negative number was added into the total residue. Series 875 does not give guidance to handle background data and does not specify if it is appropriate to correct WBD residues based on background data.

Each calculated exposure level was normalized to

g/ kg worker body weight/ day, normalizing results to EPA recommended mean adult weight of 71.8 kg and to a standard work day length of 8 hours. The " total" dermal exposure for each replicate for each worker was calculated by summing the normalized residue levels in the WBD arms, WBD top, WBD bottom ( torso portion and legs, cut apart and analyzed as separate samples), and all glove dosimeters worn during that replicate.

The levels of residue found in worker gloves and WBDs ( combined) are shown in Tables XIV, XV, and XVI ( pages 155 through 186) in the Study Report ( MRID No. 455021 01). The registrant indicated the data were lognormal and calculated geometric mean daily dermal exposure levels of monitored workers at all sites. The exposure data for all sites are summarized in Tables 6  10.

Table 6. Geometric Mean Daily Dermal Exposure Levels of Monitored Workers at all Sites for Arsenic Parameter Dermal Exposure (

g/ kg bw/ day) to Arsenic a TO TA TB TS TM LO S SO No. Replicates 15 10 5 5 5 15 5 4 Minimum 4.02 6.24 1.59 69.1 26.8 10.0 20.4 13.8 Maximum 472 39.2 8.29 148 151 190 86.8 29.0 Mean 128 19.1 3.51 102 56.8 56.9 57.0 21.3 S. D. 161 11.1 2.74 30.7 53.2 53.6 31.9 6.23 G. M. 47.9 16.3 2.91 98.0 44.3 38.0 48.3 20.6 Median 30.4 18.2 2.46 89.8 32.2 35.0 66.5 21.1 * Abbreviations: LO = Loader operator; S= supervisor, SO= stacker operator, TA = treating assistant, TB= test borer, TM= tally man, TO= treating operator, and TS= tram setter. 17 Table 7. Geometric Mean Daily Dermal Exposure Levels of Monitored Workers at all Sites for Copper Parameter Dermal Exposure (

g/ kg bw/ day) to Copper a TO TA TB TS TM LO S SO No. Replicates 15 10 5 5 5 15 5 4 Minimum 12.3 4.46 6.45 24.0 52.6 7.53 24.5 7.63 Maximum 356 67 14.0 49.9 242 110 59 24 Mean 100 28.5 10.8 37.4 98.1 43.5 40.7 17.8 S. D. 111 19.4 3.25 9.36 81.0 31.5 17.1 7.19 G. M. 56.2 22.0 10.4 36.4 80.7 32.3 37.8 16.4 Median 44.0 27.8 11.0 39.0 58.9 38.0 37.4 20.0 aAbbreviations: LO = Loader operator; S= supervisor, SO= stacker operator, TA = treating assistant, TB= test borer, TM= tally man, TO= treating operator, and TS= tram setter.

Table 8. Geometric Mean Daily Dermal Exposure Levels of Monitored Workers at all Sites for Total Chromium Parameter Dermal Exposure (

g/ kg bw/ day) to Total Chromium a TO TA TS LO S SO No. Replicates 15 10 5 15 5 4 Minimum 14.5 6.18 73.8 10.0 11.9 27.0 Maximum 233 34.7 103 109 63.2 52.8 Mean 110 19.9 87.8 46.2 46.0 40.1 S. D. 91.8 13.3 12.9 30.7 21.1 11.3 G. M. 68.5 16.1 87.0 37.1 39.7 38.9 Median 92.5 15.6 93.3 45.3 53.6 40.4 a Abbreviations: LO = Loader operator; S= supervisor, SO= stacker operator, TA = treating assistant, TO= treating operator, and TS= tram setter. 18 Table 9. Geometric Mean Daily Dermal Exposure Levels of Monitored Workers at all Sites for hex. Chromium Parameter Dermal Exposure (

g/ kg bw/ day) to Hexavalent Chromium a TO TA TS LO S SO No. Replicates 10 5 5 10 5 4 Minimum 2.02 1.43 1.75 1.48 1.78 1.41 Maximum 10.3 12.9 11.8 4.01 3.84 1.58 Mean 4.83 4.00 5.74 2.45 2.60 1.49 S. D. 3.04 5.00 3.82 0.91 0.893 0.068 G. M. 4.07 2.61 4.74 2.31 2.49 1.49 Median 3.40 1.80 5.83 2.1 2.15 1.48 a Abbreviations: LO = Loader operator, TA = treating assistant, TB= test borer, TM= tally man, and TO= treating operator.

Table 10. Geometric Mean Daily Dermal Exposure Levels of Monitored Workers at all Sites for Zinc Parameter Dermal Exposure (

g/ kg bw/ day) to Zinc a TO TA TB TM LO No. Replicates 5 10 5 5 5 Minimum 77.4 83.0 83.6 91.5 68.4 Maximum 118 156 137 147 121 Mean 95.3 113 11 114 92.6 S. D. 14.5 32.3 19.4 20.3 22.2 G. M. 94.4 110 109 113 90.5 Median 93.8 96.2 108 109 82.7 a Abbreviations: LO = Loader operator, TA = treating assistant, TB= test borer, TM= tally man, and TO= treating operator.

Inhalation Results Inhalation results were measured for each task identified in Section 3.1 for Sites A, B, and C. As noted for dermal exposure, the TS had the highest level of inhalation exposure, and had the most contact with the test materials. It appears that workers placed in the closest proximity of exposure ( e. g., TS, TM, TO, LO) were exposed to the highest quantities of target analytes. Air sampling parameters for all monitoring periods at Sites A, B, and C are shown in Tables XVIIXIX the Study Report ( MRID No. 455021 01).

The unadjusted residue level for each air sampler from each worker was corrected for the field control recovery efficiency, or for LOD/ LOQ adjustment ( if < LOQ). Inhalation exposure for each target compound was calculated from material found in the entire sampling train ( filter + front tube + rear tube). Calculated inhalation exposure levels were normalized by scaling up the pump flow rate which was approximately 2 L/ minute ( see Table XVII of the Study Report for 19 Inhalation Exposure ( µ g/ kg/ day)

Residue ( µ g/ day) x BR ( L/ hr) 60 min/ hr x WD x FR ( L/ min) x BW ( kg)

Inhalation Concentration ( µ g/ m) 3

Residue ( µ g/ day) FR ( L/ min) x Exposure ( min/ day) x WD x 1000 L/ m3 actual pump flows) to the EPA recommended minute ventilation rate of approximately 1100 L/ hour for " light activities". Then an adjustment was made for the standard EPA recommended adult weight of 71.8 kg. According to the Study Report ( MRID No. 455021 01), due to the fact that none of the workers monitored in this study performed continuous light activity, the use of the recommended ventilation rate probably resulted in a notable over estimation of exposure. The fact that values were generated even for those compounds that were never detected or quantifiable in field samples contributes to the over estimation of inhalation exposures as well. The equation for determining inhalation exposure is depicted Equation 1 below. The equation for determining inhalation concentrations are presented in Equation 2.

Equation 1:

Where:

Residue = Residue found on sampling filter ( µ g/ day); BR= Breathing rate of individual ( 1100 liters/ hour for light activities); WD= fraction of standard 8 hr day monitored; FR= Flow rate of calibrated pump ( L/ min); and BW= Body weight of individual ( 71.8 kg).

Equation 2:

Where:

Residue = Residue found on sampling filter ( µ g/ day); Exposure= Minutes worker is exposed per day ( min/ day); WD= fraction of standard 8 hr day monitored; and, FR= Flow rate of calibrated pump ( L/ min).

The calculated levels of inhalation exposures are summarized in Tables 11 15. The 8 hour inhalation concentrations are presented in Table 16. The inhalation exposures for each replicate at each site are presented in Table XX XXII ( see pages 189 191 of the MRID No. 455021 01 Study Report). The levels of each analyte in the air sampled during each monitored work cycle, expressed as

g/ m3 of air, are presented in Table XXIII ( pages 192 to 194) in the Study Report ( MRID No. 455021 01). 20 Table 11. Geometric Mean Daily Inhalation Exposure Levels of Monitored Workers at all Sites for Arsenic Parameter Inhalation Exposure (

g/ kg bw/ day) to Arsenic a TO TA TB TS TM LO S SO No. Replicates 15 10 5 5 5 15 5 4 Minimum 0.031 0.032 0.033 0.101 0.033 0.032 0.113 0.032 Maximum 0.709 0.102 0.035 0.434 0.104 0.676 0.319 0.033 Mean 0.205 0.073 0.034 0.282 0.049 0.157 0.167 0.033 S. D. 0.233 0.033 0.001 0.119 0.031 0.213 0.086 0.000 G. M. 0.107 0.065 0.034 0.256 0.044 0.086 0.154 0.033 Median 0.098 0.095 0.034 0.298 0.038 0.092 0.138 0.033 a Abbreviations: LO = Loader operator; S= supervisor, SO= stacker operator, TA = treating assistant, TB= test borer, TM= tally man, TO= treating operator, and TS= tram setter.

Table 12. Geometric Mean Daily Inhalation Exposure Levels of Monitored Workers at all Sites for Copper Parameter Inhalation Exposure (

g/ kg bw/ day) to Copper a TO TA TB TS TM LO S SO No. Replicates 15 10 5 5 5 15 5 4 Minimum 0.094 0.095 0.033 0.097 0.033 0.092 0.119 0.033 Maximum 0.778 0.297 0.101 0.971 0.113 0.656 0.595 0.967 Mean 0.293 0.12 0.048 0.455 0.078 0.27 0.397 0.299 S. D. 0.268 0.062 0.030 0.423 0.039 0.227 0.198 0.447 G. M. 0.197 0.112 0.043 0.291 0.069 0.194 0.345 0.132 Median 0.101 0.099 0.035 0.258 0.103 0.117 0.378 0.097 a Abbreviations: LO = Loader operator; S= supervisor, SO= stacker operator, TA = treating assistant, TB= test borer, TM= tally man, TO= treating operator, and TS= tram setter. 21 Table 13. Geometric Mean Daily Inhalation Exposure Levels of Monitored Workers at all Sites for Total Chromium Parameter Inhalation Exposure (

g/ kg bw/ day) to Total Chromium a TO TA TS LO S SO No. Replicates 10 5 5 15 5 4 Minimum 0.125 0.142 0.223 0.142 0.222 0.049 Maximum 0.611 0.251 0.510 0.644 0.491 0.128 Mean 0.332 0.177 0.367 0.306 0.361 0.069 S. D. 0.171 0.045 0.117 0.194 0.108 0.039 G. M. 0.291 0.173 0.352 0.260 0.348 0.062 Median 0.307 0.168 0.322 0.259 0.404 0.049 a Abbreviations: LO = Loader operator; S= supervisor, SO= stacker operator, TA = treating assistant, TB= test borer, TM= tally man, TO= treating operator, and TS= tram setter.

Table 14. Geometric Mean Daily Inhalation Exposure Levels of Monitored Workers at all Sites for Hexavalent Chromium Parameter Inhalation Exposure (

g/ kg bw/ day) to Hexavalent Chromium a TO TA TS LO S SO No. Replicates 10 5 5 10 5 4 Minimum 0.033 0.032 0.031 0.031 0.038 0.032 Maximum 0.037 0.034 0.101 0.098 0.049 0.033 Mean 0.035 0.033 0.046 0.042 0.042 0.033 S. D. 0.002 0.001 0.031 0.020 0.005 0.000 G. M. 0.035 0.033 0.040 0.040 0.042 0.033 Median 0.035 0.033 0.033 0.038 0.040 0.033 a Abbreviations: LO = Loader operator; S= supervisor, SO= stacker operator, TA = treating assistant, TB= test borer, TO= treating operator, and TS= tram setter. 22 Table 15. Geometric Mean Daily Inhalation Exposure Levels of Monitored Workers at all Sites for Zinc Parameter Inhalation Exposure (

g/ kg bw/ day) to Zinc a TO TA TB TM LO No. Replicates 5 5 5 5 5 Minimum 0.031 0.032 0.033 0.033 0.034 Maximum 0.113 0.114 0.035 0.104 0.101 Mean 0.061 0.077 0.034 0.049 0.049 S. D. 0.040 0.042 0.001 0.031 0.029 G. M. 0.051 0.066 0.034 0.044 0.044 Median 0.034 0.098 0.034 0.038 0.035 a Abbreviations: TO= treating operator, TA = treating assistant, TB= test borer, TM= tallyman, and LO= loader operator.

  Table 16. 8 Hour Inhalation Air Concentrations ( µ g/ m3)

Test Site Job Class Total As Total Cu Total Cr Hex Cr Total Zn A TA 0.803 1.001 1.41 0.268

TS 2.09 2.37 2.87 0.330

TO 0.648 0.980 1.45 0.269

LO 0.527 1.011 1.36 0.340

SO 0.267 1.08 0.508 0.267

B LO 2.25 4.58 3.31 0.309

S 1.26 2.82 2.84 0.342

TO 3.85 5.24 3.88 0.298

C TB 0.279 0.347   0.279 TO 0.287 0.862   0.358 LO 0.270 0.810   0.419 TM 0.362 0.561   0.362 TA 0.347 0.835   0.538 23 STUDY DATA REVIEW FOR COMPLIANCE WITH SERIES 875 GUIDELINES:

Compliance with Series 875 Occupational and Residential Exposure Test Guidelines of the Pesticide Assessment Guidelines ( U. S. EPA, 1998) is critical if a study is to be considered acceptable to the Agency. Table 17 presents a " Checklist for Applicator Monitoring Data" used in reviewing studies based on Series 875 guidelines. This table is designed to summarize important factors of Series 875 guidelines, identify whether the study addresses these issues, is compliant with the guidelines, and where applicable, presents comments on how the study was not in compliance. 24 Table 17. Compliance with Series 875 Guidelines FIFRA Compliance Checklist Does the Study Address This Compliance Issue? Does the Study Comply With This Part of Series 875? Comments Prior " informed consent" must be obtained in writing from all subjects who will be exposed in the study. yes yes Informed consent was presented in Appendix 2 of this report.

All conditions specified on the product label must be observed, including whatever protective clothing is specified for workers to wear. yes yes Each worker was supplied with protective clothing, gloves, respirators as needed.

Respirators were not required however because inorganic arsenic levels in the plant were less than 10 µ g/ m3.

Studies must be designed so that an exposure is measured separately for each activity associated with an application. yes yes 7 job categories were monitored.

Data collection in accordance with 40 CFR 160, Good Laboratory Practice Standards. yes mostly Page 3 in the study report indicates where GLPs could not be followed.

Typical end use product of the active ingredient used. yes yes The study identifies 3 end use products used in this study. They are Wolmanac ® Concentrate,

Timber Specialties K 33   , Chemolite Part A and Part B Solution. Labels for all four end use products were provided.

End use product handled and applied using recommend equipment, application rates,

and typical work practices. yes yes Typical wood treatment process assessed. Table 17: Compliance with Series 875 Guidelines FIFRA Compliance Checklist Does the Study Address This Compliance Issue? Does the Study Comply With This Part of Series 875? Comments 25 For exposure monitoring at least five replicates ( e. g, individuals) at each of at least three sites for each job function should be monitored. yes mostly There were 25 workers total ( for all four sites)

monitored for up to 3 consecutive work days.

There were 7 job categories monitored. For each job category there were 4 to 15 replicates per site.

Monitoring period is sufficient to collect measurable residues but not excessive so that residue loss occurs. yes yes Exposure periods seemed long enough for the tasks required.

Dermal and/ or inhalation exposure must be monitored by validated methodologies.

Biological monitoring is consistent with and supported by pharmacokinetic data accepted by the Agency. yes yes Dermal and inhalation methods used were identified in Series 875 regulations.

Quantity of active ingredient handled and duration of monitoring period reported for each replication yes partly Quantity of active ingredient handled was described. Duration of exposure was identified for both dermal and inhalation exposures. The test substances used at the facilities was used in a continuous system. However, exposure was not related in unit exposures like mg/ lb ai.

Quantitation level of detection is at least 1 µ g/ cm2 not applicable not applicable This LOQ is used only for dermal patch studies.

Clothing worn by each study participant and location of dosimeters reported. yes yes Study used whole body dosimeters ( cotton thermal shirts, pants, and gloves). Sections ( gloves, arms, bottoms) were measured appropriately. Table 17: Compliance with Series 875 Guidelines FIFRA Compliance Checklist Does the Study Address This Compliance Issue? Does the Study Comply With This Part of Series 875? Comments 26 Storage of samples consistent with storage stability data. yes yes Storage of samples and storage stability are addressed in the study. Correction based on storage stability results was not necessary.

Efficiency of extraction in laboratory provided as mean plus or minus one standard deviation. Lower 95 percent confidence limit is not less than 70 percent based on a minimum of seven replications per fortification level or prior Agency approval of extraction methodology provided. yes yes Method validation testing appeared to be in the acceptable range.

At least one field fortification sample per worker per monitoring period per fortification level for each matrix. At least one field blank per worker per monitoring period for each matrix. yes mostly Triplicate field fortifications were provided on three separate days at two fortification levels at all three sites. However, separate samples were not identified for each worker.

When collecting urine for biological monitoring, collection should involve 24 hour urine samples. A minimum of one baseline, pre exposure 24 hour sample must be collected. Twenty four hour samples must be collected for the day of application and for sufficient days postapplication as determined by the excretion profile of the pesticide. not applicable not applicable 27 SUMMARY OF DATA GAPS WITH RESPECT TO SERIES 875 GUIDELINES:

Pertinent items in regards to scientific validity and Series 875 compliance, not addressed previously, are described below. The following issues were noted:

° The amount of product applied and the amount of active ingredient handled by each worker was calculated; however exposure was not presented as a unit exposure ( mg/ lb ai).

° Triplicate field fortifications were provided on three separate days at two fortification levels at all three sites. However, separate samples were not identified for each worker. There were more workers monitored than were field fortification and field blank samples collected.

° Data were corrected for field recovery; however, only the corrected data were presented in the report. Data before correction were not reported.

CONCLUSIONS AND RECOMMENDATIONS:

The assessment for this study focused on Series 875 compliance and issues of technical merit. As indicated in the review findings cited above, the study does meet most of Series 875 guideline requirements ( the method validation, field spikes, and QA/ QC were thoroughly explained); however, some minor issues are as follows:( 1) data were not reported as unit exposures ( e. g., mg/ lb ai) therefore differences in CCA/ ACZA chemical usage, versus exposure between facilities were not examined thoroughly; ( 2) data were corrected based on field recovery; however, only the corrected data were presented in the study and the corrections calculations were not expressed; and ( 3) separate field fortification samples were not collected for each worker job function; only triplicate field fortification samples were collected at each site.

In spite of these deficiencies, the Agency considers these data as acceptable in satisfying the application exposure data guideline requirements under Series 875 for both dermal and inhalation exposure monitoring ( guidelines 875.1100/ 875.1200 for dermal and 875.1300/ 875.1400 for inhalation) and recommends use of these data, where appropriate, in developing the occupational exposure estimates for certain handler scenarios in the CCA RED human exposure chapter. It is also recommended that data from monitored workers involved with tasks that are done after the wood has been pressure treated ( e. g., data for Test Borer and Stacker Operator functions) be used in estimating certain post application exposure doses.

cc: Doreen Aviado/ RASSB/ AD( 7510C) Chemical File Circulation