and 5.8 ppb. The NOEL was reported to be < 0.12 ppb. Atrazine at concentrations at 0.12, 0.56 and 5.8 ppb, adversely effects primary production of unicellar algal species at certain growth phases and causes increases in " excretions" of dissolved organic nitrogen and phosphorus. " Excretions" may be caused by atrazine stress on cells or lysis of cells. 45020021 Bester et al., 1995 Supplemental ( raw data unavailable)

Nominal applications of 0.4,

4.5, or 45 lb ai/ A Salt marsh edaphic alage Elaboration of Plumley et al., concerning the carbon uptake for algae in the top 0.5 cm of enclosure sediment. Carbon fixation was significantly reduced at the 0.45 and 4.5 lb ai/ A treatment levels for 16 days and at the 45 lb ai/ A treatment level for 42 days. 45087406 Plumley and Davis,

1980 XI  64 f. Reported Ecological Incidents The Ecological Incident Information System ( EIIS) maintained by EFED has a total of 61 reported incidents of varying certainty for atrazine. Twelve incidents were classified as " Unlikely" and two were " Unrelated." In only one case, a cotton use, was fish carcasses analyzed for atrazine residues. The shad and carp tested positive for atrazine in the Richland, Louisiana incident ( I004021 004). Most incidents involved effects on fish kills. Other nontarget organisms affected include grasses and on occasions: corn, fruit trees, ornamentals, garden, raspberry, oats, cats, chicken, a goat, black snake and a cave amphipod.

Four incidents are listed as " Highly Probable" including a home/ lawn use incident (# I001910) and a corn use incident affecting 100 bass and 100 bream (# B000163 001) resulting from registered use. Two home/ lawn incidents affecting grass were concluded to be misuse/ accidental (# I005579 001, I005132 001). Seventeen incidents are listed as " Probable" including 7 corn incidents ( I007372 002, all bluegill and largemouth bass; I000116 002, thousand bluegill and thousand largemouth bass, I001081 001, 10 feet of grass and 600 catfish; I001081 002, bluegill and bass; B000150 003, bass and bluegill; I004697 084, fish; I000636 032, bluegill and a few crappie), 4 agricultural use incidents ( I001099 001, grass; I001041 001, fescue grass; I003826 006, not reported; I005895 074, not reported), 1 home/ lawn incident ( I000941 078, grass), 1 field incident ( I005595 001, unknown) and 1 unreported source ( I000358 004, fruit trees and garden). Two probable incidents were classified as misuse from corn use ( I005879 003, pears, raspberry and oats; I007371 013, grass and ornamentals).

Twenty six incidents were reported as " Possible" including 12 incidents affecting fish ( i. e., bluegill ( 3 incidents), catfish ( 2), bass ( 2), carp ( 1), quillback carpsucker ( 1), carp ( 1); redhorse ( 1), bream ( 1), garfish ( 1), minnow ( 1), perch ( 1), unspecified fish ( 2); cave amphipod ( 1), corn ( 4), grass ( 4), trees ( 2), plants ( 1), cat ( 1), chicken ( 1), goat ( 1), and unreported ( 3).

Given the low toxicity of atrazine to fish, aquatic invertebrates and mammals, the reason for the frequency of effects on these organisms is uncertain. About 60 percent of the reported fish kills listed under atrazine in the incident record occur during the Spring when atrazine is applied, soils are saturated and heavy rainfall is frequent. Heavy runoff may carry atrazine, other pesticides and organic loads into surface waters. The high volume and wide spread use of atrazine increases the probability of co occurrence of fish kills with atrazine applications. There are some scenarios which may explain atrazine induced fish kills as well as causes unrelated to atrazine use.

Three plausible scenarios could exist in which atrazine applications may be responsible for the fish kills. First, atrazine concentrations in surface waters from runoff and/ or spray drift may be much higher in shallow water adjacent to treated fields than estimated by EFED or found in monitoring studies. Second, atrazine in surface water may kill aquatic plants and the decaying process of dead plants may lower dissolved oxygen to levels too low for fish survival. Third, atrazine is reported to increase the toxicity of organophosphate insecticides, such as chlorpyrifos, XI  65 and a number of other pesticides which may have been applied earlier to atrazine treated crops or applied in other fields upstream in the watershed.

Possibilities also exist that other causes, not atrazine, may be responsible for some or all of the reported atrazine incidents. Heavy organic loads consume oxygen from the water as the organic matter oxidizes, thereby causing low dissolved oxygen levels which may cause fish to suffocate and die. Other pesticides in the watershed killed the fish as the water flowed past atrazinetreated fields. Since limited information is available in the atrazine incident records, such as water and tissue analyses, conclusions of responsibility would appear to be uncertain and the result of coincidence with little evidence for cause and effect.

g. Effects of Environmental Factors and Life Stage on Aquatic Atrazine Toxicity 1. Interaction Effects on Atrazine Toxicity to Plants Some intra laboratory studies suggest that atrazine toxicity is affected by some environmental parameters, such as temperature, light intensity and salinity levels. Mayer et al. ( 1998) concluded that a temperature difference of 1EC will cause a difference in algal growth rate in the range of 7 to 9 percent at the typical rate increase for 10EC temperature increase ( Q10) of 2 to 2.3.

In general, the toxicity of pesticides increase with increasing temperature. Mayasich, Karlander and Terlizzi, Jr. ( 1986) tested two algal species in 27 combinations of temperature ( 15, 20 and 25EC), light intensity ( 0.208, 0.780 and 1.352 mW/ cm2) and atrazine concentrations of 0, 50 and 100 Fg/ L) for 7 day periods. Toxic effects of atrazine on Nannochloris oculata growth rates were significantly ( p < 0.01) dependent on both temperature and light intensity as determined by the 3 way interactions. Atrazine toxicity increased to N. oculata with both increasing temperature and increasing light intensity, except at 15EC and 1.352 mW/ cm2 where growth was intermediate. Previous results yielded a similar anomaly and it suggest that 15EC is near the lower limit for growth of this algal species. With Phaeodactylum tricornutum, growth rates were significant ( p < 0.01) for light intensity and atrazine concentrations and was significant ( p < 0.05) for temperature, but only light intensity was significantly ( p < 0.01) related to an increase in atrazine toxicity. Atrazine toxicity was highest at the lowest light intensity. " The response of P. tricornutum to atrazine at light intensities of 0.780 and 1.352 mW/ cm2 is probably a reflection of primary effectsonly while at 0.208 mW/ cm2 light intensity includes secondary effects" ( Mayasich et al., 1986). With respect to the insignificant effect of temperature on growth, Ukeles ( 1961) and Fawley ( 1984) found that the growth of P. tricornutum was unchanged by temperatures in the range of 14 to 24EC and 14 to 25EC, respectively.

Mayasich et al. ( 1987) repeated the above algal study with lower atrazine concentrations ( 0, 15, 30 and 50 Fg/ L and fewer temperatures ( 15 and 25EC) and light intensities ( 0.208 and 1.352 mW/ cm2) in unialgal and bialgal assemblages. Generally Phaeodactylum tricornutum's presence significantly ( p < 0.01) depressed the growth of Nannochloris oculata, but it did not alter the magnitude of the responses to temperature, light intensity or atrazine concentrations. In contrast, the presence of N. oculata generally resulted in significant ( p < 0.01) enhancement of P. XI  66 tricornutum growth. The bialgal assemblage produced magnitudes of interactions between temperature and light intensity and temperature and atrazine were both significantly ( p < 0.01) greater for N. oculata. P. tricornutum dominated the assemblage over all concentrations of atrazine under simultaneously low levels of temperature ( 15EC) and light intensity ( 0.208 mW/ cm2). At simultaneous high levels of temperature and light intensity and the absence of atrazine. P. tricornutum and N. oculata tended to be co dominant. At increased atrazine concentrations, P. tricornutum became the dominant of the two algal species. The authors concluded that the enhanced sensitivity of N. oculata to atrazine relative to that exhibited by P. tricornutum posed threat to the diversity and structure of natural phytoplankton populations. Thus, a nutritious algal species for larval oysters ( Dupry, 1973) is replaced by what is considered to be a poor food source for larval bivalves ( Walne, 1970).

Mayer et al. ( 1998) tested the effect of four main environmental factors on the toxicity of atrazine to the green alga Selenastrum capricornutum in 3 day tests. The four factors tested were light intensity ( 44 and 198 FE/ m2), temperature ( 16 and 26EC), nitrogen source ( NH4+ and NO3) and pH ( 7.6 and 8.6). Temperature influenced growth only indirectly by interacting with light intensity. Algal growth measured as the atrazine EC50 values was marginally reduced under low light intensity at high and low temperatures ( 158 and 159 Fg/ L, respectively versus the atrazine control, 164 Fg/ L). High light intensity at the low temperature reduced the toxicity of atrazine to the alga by about two fold ( LC50 300 Fg/ L) while high light intensity and high temperature reduced the toxicity of the atrazine by about 118 fold ( LC50 191 Fg/ L). Nitrogen source and pH had no significant effect on atrazine toxicity affecting algal growth rates.

The above studies indicate that the toxicity of atrazine to plants can be affected by environmental parameters, but differences in those effects occur depending on the algal species. Hence, increases in temperature may increase, decrease or have no effect on atrazine toxicity to algal growth. Light intensity generally has the stronger effect on atrazine toxicity to algal growth and may, short of the point of photo inhibition, increase the toxicity of atrazine. Nitrogen source and pH do not have any effect on the toxicity of atrazine to algae.

2. Interaction Effects on Atrazine Toxicity to Aquatic Animals Some intra laboratory studies suggest that atrazine toxicity to aquatic animals is affected by environmental parameters, such as water hardness, salinity and differences in the life stages of organisms.

High levels of water hardness usually reduce the toxicity of pesticides. Intra laboratory studies on two fish species provide comparative LC50 values for two levels of water hardness ( Birge, Black and Bruser, 1979). Embryo larval rainbow trout were exposed to atrazine for 27 days at water hardness levels of 50 and 200 mg/ L and produced LC50 values of 0.66 and 0.81 mg/ L, respectively. The test with channel catfish at the same water hardness levels for 8 days and yielded LC50 values of 0.22 and 0.23 mg/ L. With rainbow trout embryo larvae, the soft water increased toxicity by about 19 percent, while the LC50 values for embryo larval catfish were the same. It is uncertain, if the shorter exposure period, yolk sac or differences in species sensitivity, XI  67 account for the difference in water hardness effects between embryo larvae of channel catfish and rainbow trout.

Salinity effects at 5, 15 and 25 g/ L on the toxicity of atrazine are opposite for the estuarine fish larvae, sheepshead minnow and the copepod nauplii, Eurytemora affinis ( Ziegenfuss, Anderson, Spittler and Leichtweis, 1994). The 96 hour LC50 values ( 16.2, 2.3 and 2.0 mg/ L) for sheepshead minnow consistently increased with increasing salinity. In the case of the copepod nauplii, the 96 hour LC50 values ( i. e., 0.5, 2.6 and 13.3 mg/ L) consistently decreased with increasing salinity. The consistency of the two data sets suggest that salinity effects the toxicity of atrazine. Statistical tests for both species indicate significant differences between the LC50 valves at 5 and 25 g/ L, but not at 15 g/ L. The authors concluded that the two species may be more physiologically effective in metabolizing and mitigating toxic effects of atrazine at various salinities. The increase in LC50 values for rainbow trout and sheepshead minnow are consistent for increasing water hardness and increasing salinity.

For many pesticides, the earlier life stages are normally more toxic to organisms than later lifestages Contrary to most pesticides, the aquatic toxicity data for toad and frog tadpoles suggest that the late stages are more sensitive to atrazine than early tadpole stages ( Howe et al., 1998). The late stage of the American toad tadpole is about 2.5 times more sensitive to atrazine than the early stage ( 10.7 versus 26.5 mg/ L). For the northern leopard frog tadpoles, the later stage is about 3.3 times more toxic than the early tadpole stage ( 14.5 versus 47.6 mg/ L).

The above studies suggest that decreases in water hardness and salinity can increase the toxicity of atrazine to fish, but increasing salinity may mitigate atrazine toxicity to copepods. Life stages show differences in sensitivity to atrazine. The later stages in frog and toad tadpole development show an increased sensitivity to atrazine over early tadpole stages.

h. Pesticide Toxicity Interactions 1. Plants A number of authors have reported toxic interactions between atrazine, its dealkylated degradates and other pesticides. Synergism between atrazine and a number of other pesticides has also been reported in aquatic organisms, particularly with organophosphate insecticides, a carbamate insecticide and other herbicides.

In 1974, Putnam and Penner reported on the effects of interactions of herbicides on higher plants. Atrazine was cited in test combinations with 5 herbicides, 2 insecticides and a fungicide. Synergistic effects ( i. e., increased toxicity higher than additivity) was identified in 6 out of the 8 test combinations. Atrazine was synergistic with 4 herbicides ( i. e., 2, 4 D ( oil), paraquat, EPTC, and alachlor) and 2 insecticides ( i. e., diazinon and fensulfothion). Atrazine test combinations with dalapon, a herbicide, and dexon, a fungicide, showed antagonistic interactions. XI  68 Torres and O'Flaherty ( 1976) report additive toxicity of atrazine with simazine at concentrations of 1.0 ug/ L and 1 mg/ L for Chlorella vulgaris, Stigeoclonium tenue, Tribonema sp., Vaucheria geminata, and Oscillatoria lutea. Additive toxicity of malathion with atrazine was found in Chlorella vulgaris, but could not be assessed with other species, because malathion produced total inhibition of chlorophyll production at 1 ug/ L or greater concentrations. At 1 and 1,000 ug/ L, pesticides mixtures increased toxicity from 2.4 to 100 percent over the toxic levels of atrazine alone. Mixtures of these pesticides at concentrations of 0.1 and 0.5 ug/ L usually enhanced the production of chlorophyll.

Stratton ( 1984) also tested the most sensitive algal species, Anabaena inaequalis, with mixtures of atrazine and its two most toxic degradates, deethylatrazine and deisopropylatrazine. Cell count results indicate that combinations of atrazine/ deethylatrazine ( 1.8) and atrazine/ deisopropylatrazine ( 1.3) are synergistic and deethylatrazine/ deisopropyl atrazine mixtures are additive ( 1.03). For photosynthesis, results after 3 hour exposures indicate that all mixture combinations for these three chemicals are antagonistic ( 0.8, 0.86, and 0.89).

Burrell et al. ( 1985) reported 11 day interactions between algal populations and between algal populations and pesticides. Population interactions showed that Chlorella vulgaris inhibited population growth of Ankistrodesmus braunii by 32 percent. The addition of the bacterium, Chromobacterium violaceum, added to the algal mixture further inhibited population growth of A. braunii by an additional 17% and bacterial growth was stimulated, but the bacterium had no effect on Chlorella populations. The combined effect of the mixtures of atrazine ( 60 Fg/ L) and sodium pentachlorophenate ( Na PCP) ( 0, 300, 800, 1,000 and 1,200 Fg/ L) and atrazine ( 40 and 100 Fg/ L) with Na PCP ( 700 and 1,200 Fg/ L) on A. braunii populations were additive over a wide range of concentrations. Similar results of atrazine ( 10 and 100 Fg/ L) and Na PCP ( 300 and 1,200 Fg/ L) were obtained with C. vulgaris. In mixed algal cultures tested with atrazine ( 40 and 100 Fg/ L), cell numbers of A. braunii were reduced 50 and 80 percent, respectively, which was not significantly different than effects when tested alone. In the same mixed culture test, atrazine inhibited growth of C. vulgaris by 79 and 85 percent, respectively, which showed a significant growth inhibition only at the lower test concentration ( 40 Fg/ L). The authors concluded that the high atrazine concentration ( 100 Fg/ L) did not alter the established population relationship between the two algal species, but at the lower concentration ( 40 Fg/ L), A. braunii increased the susceptibility of C. vulgaris to atrazine. When mixed cultures of algae were treated with both atrazine ( 60 Fg/ L) and Na PCP ( 300, 800, 1,000 and 1,200 Fg/ L), chemical antagonism was observed. The addition of the bacterium, C. violaceum, to the microcosm, had no effect on the level of antagonism for A. braunii. C. violaceum modified the antagonism of atrazine toxicity to C. vulgaris by about 40 percent, but the antagonistic effect was not eliminated. The net atrazine toxicity decreased as the Na PCP concentration increased. The authors found no reason for the modification of atrazine effects by C. violaceum.

Carder and Hoagland ( 1998) reported that pesticide interactions of atrazine ( 0, 12 and 150 Fg/ L) and alachlor ( 0, 5, 90 Fg/ L) on benthic algal communities in artificial recirculating streams showed significant interaction ( i. e., antagonism) only in the first week in the combination of high alachlor and low atrazine test concentrations. The authors concluded that the interaction is most XI  69 likely anomalous and the lack of significant synergistic effects may be attributed to different modes of action.

2. Aquatic Animals A number of authors have reported synergistic effects of atrazine with the aquatic animals with one or more of the following pesticides: ( i. e., alachlor, chlorpyrifos, DDT, malathion, methyl parathion, parathion and trichlorfon).

Liang and Lichtenstein ( 1975) also found atrazine synergism between soil residues of both DDT and parathion using fruit flies, Drosophila melanogaster and measured lethal effects versus the age of the pesticide residues in soil. Ten grams of Plainfield sand ( 1.2 % organic matter) or Plano silt loam ( 4.7% organic matter) was mixed with parathion ( 2.3 Fg/ 10 g of soil = 0.23 ppm) or DDT ( 30 Fg/ 10 g of soil = 3 ppm), then was mixed with 10 g of the same soil type, which contained increasing atrazine levels ( 40 to 1000 Fg/ 10 g of soil = 4 to 100 ppm) or controls. Fifty fruit flies were placed in 120 ml test jars for 24 hours with the 10 g portions of air dried soil untreated or treated with atrazine, parathion, DDT or combinations thereof. The resulting 24 hour fruit fly LD50 values for constant soil levels of parathion ( 2.3 ppm) and DDT ( 3.0 ppm) were as follows: parathion ( 6.2 ppm atrazine in sand and 92 ppm in loam) and DDT ( 8.5 ppm atrazine in sand and 68 ppm in loam). Synergistic effects were apparent in all test combinations of soil and pesticides yielding a dose response effect on fly mortality with increasing atrazine soil concentrations. Fruit fly mortality levels with both parathion and DDT in soils also clearly indicate a strong reduction in toxicity with the silt loam soil with a higher percentage of organic matter ( 4.7%) compared to sandy soil ( 1.2%).

Additional loam soil toxicity tests were conducted daily for 4 days, with aged atrazine soil with an initial 50 ppm aged in the dark at 22EC and both fresh and aging parathion soil levels ( 0.35 ppm). In the test with fresh parathion soils and aged atrazine soils, toxicity to fruit flies decreased linearly from 95% mortality on Day 0 to 43.3% over four days. By the fourth day, atrazine levels had declined to 19 ppm, which was barely enough to synergize parathion in loam soils. In another toxicity test, parathion treated soils were aged under the same conditions as above and added it daily to the initial 10 g of atrazine treated soil ( 50 ppm). In this test, the toxicity to fruit flies decreased logarithmically from about 68% on Day 0 to 10% mortality on Day 4. The measured concentrations of aging parathion in the silt loam soil decreased at a rate paralleling the logarithmic toxicity curve. The final parathion level on Day 4 was 0.24 ppm.

Liang and Lichtenstein ( 1975) found atrazine to be synergistic with parathion in 24 hour aquatic tests with third instar mosquito larvae, Aeddes aegypti and also assessed the effects of sand and loam soils on their individual and combined toxicity in 20 ml of pesticide treated water. Atrazine at 10,000 Fg/ L showed no toxicity to the mosquito larvae; alone, parathion ( 15 Fg/ L) killed 20 + 7 percent of the larvae; and at these concentrations, the combination of the two pesticides produced significantly ( p = 0.01) higher mortality ( 73 + 18 %). Addition of 5 g of Plainfield sand ( 1.2% organic matter) with 15 Fg/ L parathion reduced the toxicity of parathion from 20 + 7% to 18 + 4%, but when sand was mixed into the water, mortality drop to 5%. Plano XI  70 silt loam soil ( 4.7% organic matter) without mixing reduced parathion toxicity from 20 + 7% to 5 + 4% and when the loam soil was mixed into the water, no mosquito larvae died. When these two soils were added to the same combination of atrazine and parathion, sand reduced the mortality from 73 + 14% to 71 + 14% ( unmixed) and to 18 + 4 % when mixed into the water; loam soil reduced the mortality from 73% to 64 + 4% ( unmixed) and to no mortality with mixing. The combination of atrazine and parathion was significantly ( p = 0.01) more toxic than the toxicity of parathion or atrazine alone.

The above toxicity test method was repeated using 1 and 5 grams of sand or silt loam to measure the effect of different amounts of soil on toxicity following 24 hour exposures. Atrazine ( 10 ppm) produced no mortality in 24 hours to mosquito larvae. Parathion ( 0.015 ppm) produced 24 + 7% mortality ( no soil), 16 + 7% ( 1g of sand), 2 + 2% ( 5 g of sand), 7 + 0% ( 1 g of loam soil) and 0% ( 5 g of loam soil). The combination of atrazine ( 10 ppm) and parathion ( 0.015 ppm) showed synergistic effects on mosquito larvae mortality: 62 + 8% ( no soil), 42 + 10% ( 1 g of sand), 2 + 2% ( 5 g of sand), 22 + 4% ( 1 g of loam soil) and 0% ( 5 g of loam soil). These test format was repeated using higher pesticide concentrations and again the mortality levels were increased with a mixture of atrazine ( 20 ppm) and parathion ( 0.30), but the synergistic increase was much lower than in the previous test. The 24 hour results indicated that atrazine alone was not toxic to mosquito larvae; 0.30 ppm parathion ( 93 + 6% mortality with on soil), 62 + 8% with 5 g of sand and no mortality with silt loam soil. The mixture of 20 ppm atrazine and 0.30 ppm parathion produced 98 + 4% mortality with no soil, 76 + 4% dead when shaken with 5 g of sand, and 38 + 10% lethality when shaken with 5 g of silt loam soil. These studies demonstrate that atrazine is synergistic with parathion and, like single toxicants, organic matter in soils and sediments will modify toxicity of pesticide mixtures, especially if the organic matter is suspended in the water. While this particular study has limited value for risk assessment, because the atrazine levels ( 10 and 20 ppm) exceed the normal environmental range of atrazine exposures, the study suggests that synergism of atrazine and parathion may occur at lower concentrations, possibly in the range of environment levels of atrazine.

Pape Lindstrom and Lydy ( 1997) tested atrazine with 6 pesticides for chemical interactions using 4th instar midges ( Chironomus tentans). The 96 hour test results for the pesticide mixtures indicated that atrazine was synergistic with the phosphonate insecticide, trichlorfon, ( 0.26 toxic units) and 3 phosphorothioate insecticides ( i. e., malathion ( 0.36 TU), chlorpyrifos ( 0.58 TU) and methyl parathion ( 0.59 TU). The atrazine mevinophos ( a phosphate) mixture was less than additive ( 1.34 TU), while methoxychlor, a organochlorine insecticide mixture was also less than additive ( 1.67 TU). The results from these tests are questionable, since DMSO was used as a solvent with atrazine. These tests were repeated by Belden and Lydy ( 2000) without DMSO and with lower atrazine concentrations ( 0, 10, 40, 80, and 200 Fg/ L). Acute 96 hour tests with Chironomus tentans were conducted with each pesticide and EC1, EC5, EC15 and EC50 values were determined based on inability of the midge to swim when prodded with forceps. Chemical interactions were tested at each of these EC levels with atrazine levels of 0, 10, 40, 80 and 200 Fg/ L using 5 replicates of 10 midges each. Atrazine increased the toxicity of chlorpyrifos, diazinon and parathion, but not malathion. The authors concluded that " Interaction terms were not significant for atrazine + methyl parathion and atrazine + diazinon; however, a significant XI  71 interaction was found for the atrazine + chlorpyrifos test ( p = 0.002, df  12, F = 2.94)." Synergistic ratios were reported as follows: chlorpyrifos, 1.83 at 40 Fg/ L and 4.00 at 200 Fg/ L atrazine; at 200 Fg/ L diazinon the SR was 2.71 and for methyl parathion, the SR was 1.94. The variety of chemical interactions produced by atrazine mixtures indicates that the effect of atrazine on an organism is dependent on the species, cocontaminant, and the concentration of atrazine. Additional tests with 200 Fg/ L atrazine and chlorpyrifos showed that atrazine increased the uptake of chlorpyrifos by 42 percent, and that the atrazine induction of cytochrome P450 increased the formation of the O analog which increased the toxicity of chlorpyrifos at enviromentally relevant concentrations.

Howe et al. 1998 reported synergism between atrazine and alachlor, a herbicide, in tests with young rainbow trout, channel catfish and early and late tadpole stages of the northern frog and the American toad. The results are presented in the table below. ( MRID # 45202910).

Species ( stage) Time ( hour) Atrazine LC50 ( 95% CI) mg/ L Alachlor LC50 ( 95% CI) mg/ L Atrazine Alachlor LC50a ( 95% CI) mg/ L Additive Indexb ( 95% CI)

Rainbow trout ( 0.8 1.0 gram juveniles) 24 96 31.6 ( 28.2  35.4) 20.5 ( 18.3  22.9) 10.6 ( 9.5  11.7) 9.1 ( 9.0  9.2) 9.5 ( 8.3  10.9) 6.5 ( 5.7  7.7)  0.20 ( 0.53 0.059)  0.03 ( 0.28 0.15)

Channel catfish ( 0.9 1.1 gram juveniles) 24 96 51.3 ( 44.6  59.0) 23.8 ( 22.3  25.5) 23.8 ( 22.7  25.0) 16.7 ( 15.1  18.4) 11.1 ( 9.6  12.4) 7.5 ( 5.3  8.4) 0.29 ( 0.067 0.55) c 0.31 ( 0.072 0.57) c Northern leopard frog ( 0.7 0.9 gr early larvae) 24 96 69.7 ( 63.1  77.2) 47.6 ( 41.4  54.8) 14.9 ( 13.3  16.6) 11.5 ( 10.1  13.2) 12.1 ( 11.0  12.9) 6.5 ( 5.7  7.7) 0.015 ( 0.17 0.24) 0.43 ( 0.054 0.87) c Northern leopard frog ( 1.4 1.9 gr late larvae) 24 96 45.3 ( 42.3  48.5) 14.5 ( 11.9  17.5) 7.3 ( 6.6  8.0) 3.5 ( 3.1  3.8) 5.9 ( 5.5  6.4) 2.1 ( 2.0  2.3) 0.07 ( 0.12 0.25) 0.34 ( 0.069 0.56) c American Toad ( 0.1 0.2 gr early larvae) 24 96 66.4 ( 58.9  74.9) 26.5 ( 23.0  30.5) 5.7 ( 4.7  5.8) 3.9 ( 3.7  4.2) 4.4 ( 4.2  4.6) 1.8 ( 1.7  1.9) 0.19 ( 0.057 0.28) 0.89 ( 0.68  1.2 ) c American Toad ( 0.4 0.5 gr late larvae) 24 96 15.8 ( 13.5  18.4) 10.7 ( 9.2  12.5) 4.3 ( 3.8  4.8) 3.3 ( 2.8  3.6) 2.9 ( 2.6  3.3) 1.5 ( 1.4  1.6) 0.17 ( 0.11  0.46) c 0.68 ( 0.34  1.0 ) c a 50: 50 mixture of atrazine 4L ( 40.8% ai.) and alachlor EC ( 43.0% ai.). b An additive index greater than zero indicates greater than additive toxicity. c Significant chemical synergy interaction between atrazine and alachlor.

h. US EPA, Office of Water, Water Quality Criteria The Office of Water sets ambient aquatic life water quality criteria to be used under two sections of the Clean Water Act, section 304( a)( 1) and section 303( c)( 2). In section 304, the term represents a non regulatory, scientific assessment of ecological effects. If water quality criteria associated with specific stream uses are adopted by a state as water quality standards under section 303, they become enforceable maximum acceptable pollutant concentrations in ambient waters within that state. Water quality criteria adopted in state water quality standards could have the same numerical values as criteria developed under section 304. However, in many situations states might want to adjust water quality criteria developed under section 304 to reflect local environmental conditions and human exposure patterns. Alternatively, states may use different data and assumptions than EPA in deriving numeric criteria that are scientifically XI  72 defensible and protective of designated uses. It is not until their adoption as a part state water quality standards that criteria become regulatory.

The ambient aquatic life water quality criteria for atrazine is currently under review. An atrazine draft dated, 6/ 12/ 00, has been published for public comment. The proposed water quality criteria values for atrazine are presented in the table below.

OW, Water Quality Criteria for Atrazine ( Fg/ L)

Final Acute Value Fish Chronic Value Invertebrate Chronic Value Freshwater Criteria 657.3 11.56 85.11 Saltwater Criteria 641.5 11.28 83.06 h. US EPA, OPP, Terrestrial and Aquatic Most Sensitive Toxicity Values The most sensitive terrestrial and aquatic toxicity values used to assess risks from pesticide use are presented in the table below.

OPP, Terrestrial and Aquatic Toxicity Values for Atrazine Acute Value Dietary Value Chronic Value Terrestrial Organisms: Birds Mammals ( mg/ kg) 940 224 ( ppm) > 5,000 ( 30 % dead)   ( ppm) < 75 50 Freshwater Organisms: Fish Invertebrates ( Fg/ L) 4,500 720     ( Fg/ L) 65 60 Saltwater Organisms: Fish Invertebrates ( Fg/ L) 8,500 88     ( Fg/ L) 1,900 80 Terrestrial Plants: Seedling Emergence: Dicot Monocot Vegetative Vigor; Dicot Monocot ( lbs ai/ A)

0.003 0.004 0.008 0.61                 XI  73 Aquatic Plants: Freshwater Plants: Algae Vascular Plants Saltwater Plants: Algae Vascular Plants ( Fg/ L)

< 1 2 10 < 4 ( Fg/ L)

25 2 22 8 i. References Abou Waly, Hoda, M. M. Abou Setta, H. N. Nigg and L. L. Mallory. 1991. Growth response of freshwater algae, Anabaena flos aquae and Selenastrum capricornutum to Atrazine and hexazinone herbicides. Bull. Environ. Contam. Toxicol. 46: 223 229.

Alazemi, B. M., J. W. Lewis and E. B. Andrews. 1996. Gill damage in the freshwater fish Gnathonemus petersii ( Family: Mormyridae) exposed to selected pollutants: An ultrastructural study. Environ. Technol. 17: 225 238. ( MRID # 45202905).

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Van Zwieten, L. and I. R. Kennedy. 1995. Rapid degradation of atrazine by Rhodococcus sp. N186/ 21 and by an atrazine perfused soil. J. Agr. Food Chem. 43( 5): 1377 1383.

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Beliles, R. P. and W. J. Scott, Jr. 1965. Atrazine safety evaluation on fish and wildlife ( Bobwhite quail, mallard ducks, rainbow trout, sunfish, goldfish). Prepared by Woodard Res. Corp.; submitted by Geigy Chemical Co., Ardsley, NY. ( MRID No. 00059214).

Beliles, R. P. and W. J. Scott, Jr. 1965. Atrazine safety evaluation on fish and wildlife ( Bobwhite quail, mallard ducks, rainbow trout, sunfish, goldfish): Atrazine: Acute toxicity in goldfish. Prepared by Woodard Res. Corp.; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 00024718).

Beliles, R. P. and W. J. Scott, Jr. 1965. Atrazine safety evaluation on fish and wildlife Bobwhite quail, mallard ducks, rainbow trout, sunfish, goldfish): Atrazine: Acute toxicity in rainbow trout. Prepared by Woodard Res. Corp.; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 00024716).

Beliles, R. P. and W. J. Scott, Jr. 1965. Atrazine safety evaluation on fish and wildlife ( Bobwhite quail, mallard ducks, rainbow trout, sunfish, goldfish): Atrazine: Acute toxicity in sunfish. Prepared by Woodard Res. Corp.; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 00024717).

Bentley, R. E. and K. J. Macek. 1973. Acute toxicity of atrazine to mud crab ( Neopanope texana). Prepared by Bionomics, Inc.; Submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 00024719).

Buccafusco, R. 1976. Acute toxicity of Atrazina technical to bluegill ( Lepomis macrochirus). Prepared by EG & G Bionomics, Wareham, MA; submitted by unknown. ( MRID No. 00147125).

Chetram, R. S. 1989. Atrazine: Tier 2 seed emergence nontarget phytotoxicity test. Lab, Study No. LR 89 07C. Prepared by Pan Agricultural Laboratories, Inc., Madera, CA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 42041403).

Chetram, R. S. 1989. Atrazine: Tier 2 seed germination nontarget phytotoxicity test. Lab, Study No. LR 89 07B. Prepared by Pan Agricultural Laboratories, Inc., Madera, CA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 41223001).

Chetram, R. S. 1989. Atrazine: Tier 2 vegetative vigor nontarget phytotoxicity test, Lab, Study No. LR 89 07A. Prepared by Pan Agricultural Laboratories, Inc., Madera, CA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 41223003).

Chetram, R. S. 1989. Atrazine: Tier 2 vegetative vigor nontarget phytotoxicity test, Lab, XII  2 Study No. LR 89 07A. Prepared by Pan Agricultural Laboratories, Inc., Madera, CA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 42041402).

Dionne, E. 1992. Atrazine technical   Chronic toxicity to the fathead minnow ( Pimephales promelas) during a full life cycle exposure. SLI Report No. 92 7 4324. Prepared by Springborn Laboratories, Inc., Wareham, MA; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 42547103).

Drake, C. H. 1976. Acute toxicity of technical NC 1659 ( atrazine) to Daphnia magna. Lab. Rep. No. BIOSC/ 76/ E/ 12. Prepared by Fisons, Ltd., submitted by Fisons Corp., Agricultural Chemicals Div., Bedford, MA. ( MRID No. 00027204).

Fink, R. 1976. Final report: Acute oral LD50   Bobwhite quail. Project No. 108 123. Prepared by Wildlife International, Ltd., Easton, MD; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 00024721).

Gross, T. S. 2001. Determination of potential effects of 10 day neonatal exposure of atrazine on histological and hormonal sex determination in incubated American alligator ( Alligator mississippiensis) eggs. Prepared by University of Florida, Wildlife Reproductive Toxicology Laboratory, Gainesville, FL, NOVA98,02a; submitted by Syngenta Crop Protection, Inc., Greensboro, NC. ( MRID No. 45545302).

Gross, T. S. 2001. Determination of potential effects of 10 day neonatal exposure of atrazine on histological and hormonal sex determination in incubated red eared slider ( Pseudemys elegans) eggs. Prepared by University of Florida, Wildlife Reproductive Toxicology Laboratory, Gainesville, FL, NOVA98,02b; submitted by Syngenta Crop Protection, Inc., Greensboro, NC. ( MRID No. 45545303).

Heath, R. G., J. W. Spann, E. F. Hill and J. F. Kreitzer. 1972. Comparative dietary toxicities of pesticides to birds. Prepared by U. S. Dept. Interior, Bureau Sport Fish. Wildlife, Spec. Rep.  Wildlife. No., 152. 57 p.; submitted by Fisons Corp. ( MRID No. 00058746).

Hoberg, J. R. 1991. Atrazine technical: Toxicity to the freshwater green alga Selenastrum capricornutum. SLI Rep. No. 91 1 3600. Prepared by Springborn Laboratories, Inc., Wareham, MA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 42060701).

Hoberg, J. R. 1991. Atrazine technical: Toxicity to the duckweed Lemna gibba G3. SLI Rep. No. 91 1 3613. Prepared by Springborn Laboratories, Inc., Wareham, MA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 42041404).

Hoberg, J. R. 1993. Atrazine technical: Toxicity to duckweed, ( Lemna gibba). SLI Rep. No. 93 4 4755. Prepared by Springborn Laboratories, Inc., Wareham, MA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 43074804). XII  3 Hoberg, J. R. 1993. Atrazine technical: Toxicity to duckweed, ( Lemna gibba). SLI Rep. No. 93 11 5053. Prepared by Springborn Laboratories, Inc., Wareham, MA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 43074803).

Hoberg, J. R. 1993. Atrazine technical: Toxicity to the freshwater green alga, ( Selenastrum capricornutum). SLI Rep. No. 93 4 4751. Prepared by Springborn Laboratories, Inc., Wareham, MA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 43074802).

Hoberg, J. R. 1993. Atrazine technical: Toxicity to the marine diatom, ( Skeletonema costatum). SLI Rep. No. 93 4 4753. Prepared by Springborn Laboratories, Inc., Wareham, MA.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 43074801).

Hughes, J. R. 1986. The toxicity of atrazine, Lot No. FL 850612 to four species of aquatic plants. Lab. Study No. 267 28 1100. Prepared by Malcolm Pirnie, Inc., White Plains, NY.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 41065203).

Macek, K. J., K. S. Buxton, S. Sauter, S. Gnilka and J. W. Dean. 1976. Chronic toxicity of atrazine to selected aquatic invertebrates and fishes. Prepared by EG & G Bionomics, Inc., Duluth, MN; submitted by Shell Chemical Co., Washington, D. C. ( MRID No. 00024377).

Machado, M. W. 1994. Atrazine technical  Acute toxicity to mysid shrimp ( Mysidopsis bahia) under flow through conditions. Prepared by Springborn Laboratories, Inc., Wareham, MA; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 43344902).

Machado, M. W. 1994. Atrazine technical  Acute toxicity to sheepshead minnow ( Cyprinodon variegatus) under flow through conditions. Prepared by Springborn Laboratories, Inc., Wareham, MA; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 43344901).

Madsen, T. J. 2000. Effects of atrazine on the sex ratio of Daphnia pulicaria. Prepared by ABC Laboratories, Inc., Columbia, MO, ABC Study No. 45810; submitted by Novartis Crop Protection, Inc., Greensboro, NC. ( MRID No. 45299504).

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Parrish, R. 1978. Effects of atrazine on two freshwater and five marine algae. Lab. Study No. H82 500. Prepared by E G & G Bionomics, Marine Research Laboratory, Pensacola, FL.; submitted by Ciba Geigy Corporation, Greensboro, NC. ( MRID No. 41065204). XII  4 Pedersen, C. A. and D. R. DuCharme. 1992. Atrazine technical: Toxicity and reproduction study in bobwhite quail. Lab. Proj. ID. No. BLAL No. 102 012 07. Prepared by Bio Life Associates, Ltd., Neillsville, WI; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 42547102).

Pedersen, C. A. and D. R. DuCharme. 1992. Atrazine technical: Toxicity and reproduction study in mallard ducks. Lab. Proj. ID. No. BLAL No. 102 013 08. Prepared by Bio Life Associates, Ltd., Neillsville, WI; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 42547101).

Putt, Arthur E. 1991. Atrazine 80% WP: Acute toxicity to daphnids ( Daphnia magna) underflow through conditions. Lab. Study No. 91 5 3761. Prepared by Springborn Laboratories, Inc., Wareham, MA.; submitted by Ciba Geigy Corporation. ( MRID # 42041401)

Sachsse, K. and L. Ullmann. 1974. Acute oral LD50 of technical atrazin ( G 30027) in the Japanese quail. Project No. Siss 4407. Prepared by Ciba Geigy, Ltd., Basle, Switzerland; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 00024722).

Sachsse, K. and L. Ullmann. 1975. 8 Day feeding toxicity of technical G30027 ( Atrazine) in the Japanese quail. Prepared by Ciba Geigy, Ltd., Basle, Switzerland; submitted by Ciba Geigy Corp., Greensboro, NC. ( MRID No. 00024723).

Tucker, R. K. and D. G. Crabtree. 1970. Handbook of toxicity of pesticides to wildlife. U. S. Dept. Interior, Bureau Sport Fish. Wildlife, Denver Wildlife Res. Center. Submitted by Fison Corp. ( MRID No. ???????).

Union Carbide Corp. 1975. Acute toxicity of SD 12011, Code 4 1 2 1 and Code 4 1 3 1 to fiddler crabs, Uca pugilator. Prepared by Union Carbide Corp.; submitted by Shell Chemical Co., Washington, D. C. ( MRID No. 00024395).

Wieser, C. M. and T. Gross. 2002. Determination of potential effects of 20 day exposure of atrazine on endocrine function in adult largemouth bass ( Micropterus salmoides). Prepared by University of Florida, Wildlife Reproductive Toxicology Laboratory, Gainesville, FL, Wildlife No. NOVA98.02e; submitted by Syngenta Crop Protection, Inc., Greensboro, NC. ( MRID No. 45622304). XIII  1 Appendix XIII. Data Requirement Tables _________________________________________________________________________________________________________

ENVIRONMENTAL FATE Case No: 0??? DATA REQUIREMENTS FOR Chemical No: 080803 ATRAZINE Does EPA Have Must Additional Use Data To Satisfy Bibliographic Data Be Submitted Data Requirement Pattern1 This Requirement? Citation under FIFRA 3( c)( 2)( B)?

( Yes, No, or Partially)

§ 158.290 ENVIRONMENTAL FATE Degradation Studies Lab:

161 1 Hydrolysis ABCJK yes 40431319 no 161 2 Photodegradation In Water ABCJK yes 42089904 no 161 3 Photodegradation On Soil ABCJK yes 40431320,42089905 no 161 4 Photodegradation In Air no Metabolism Studies Lab:

162 1 Aerobic Soil ABCJK yes 42089906 no 162 2 Anaerobic Soil ABCJK yes 42089906 no 162 3 Anaerobic Aquatic ABCJK yes 40431323 no 162 4 Aerobic Aquatic ABCJK no yes Mobility Studies:

163 1 Leaching Adsorption/ Desorp. ABCJK yes 40331324,40431327,40431325 no 40431328,40431326 163 2 Volatility ( Lab) ABCJK no yes 163 3 Volatility ( Field) ABCJK no ???

Dissipation Studies Field:

164 1 Soil Dissipation ABCJK yes 42165504,42165505,40431336, no 42165506,40431337,421655507 164 2 Aquatic ( Sediment) ABCJK no yes 164 3 Forestry ABCJK yes 40431340,42041405 no 164 5 Soil, Long term ABCJK yes 40431339, 42089911,40431337 no XIII  2 42089912,40431338,42089909 40431336,42089910 Accumulation Studies:

165 3 Irrigated Crops 165 4 In Fish ABCJK yes 40431344 no 165 5 In Aquatic Non Target Org. ABCJK no yes Ground Water Studies:

166 1 Ground Water Small Prosp.

166 2 Ground Water Small Retro.

Surface Water Studies:

167 1 Field Runoff 167 2 Surface Water Monitoring § 158.440 Spray Drift:

201 1 Droplet Size Spectrum ABCJK no yes 202 1 Drift Field Evaluation ABCJK no yes 1 Use Patterns: A= Terrestrial Food Crop; B= Terrestrial Feed Crop; C= Terrestrial Non Food Crop; D= Aquatic Food Crop; E= Aquatic Non

Food Outdoor; F= Aquatic Non Food Industrial; G= Aquatic Non food Residential; H= Greenhouse Food Crop; I= Greenhouse Non

Food Crop; J= Forestry; K= Outdoor Recreation; L= Indoor Food; M= Indoor Non Food; N= Indoor Medical; O= Indoor Residential; Z= Use Group for Site 00000 * In Bibliographic Citation column indicates study may be upgradeable XIII  3 Date: November 2000 PHASE IV Case No: DATA REQUIREMENTS FOR Chemical No: 080803 ECOLOGICAL EFFECTS BRANCH Data Requirements Composition1 Use Pattern2 Does EPA Have Data To Satisfy This Requirement?

( Yes, No) Bibliographic Citation ( MRID) Must Additional Data Be Submitted under FIFRA3( c)( 2)( B)?

6 Basic Studies in Bold 71 1( a) Acute Avian Oral, Quail/ Duck Northern Quail to be tested TGAI 3 Major Degradates ABCJK ABCJK yes no 00024721 no yes 71 1( b) Acute Avian Oral, Quail/ Duck ( TEP) no 71 2( a) Acute Avian Diet, Quail TGAI Degradates ABCJK ABCJK yes no 00022923 no reserved 71 2( b) Acute Avian Diet, Duck TGAI ABCJK yes 00022923 no 71 3 Wild Mammal Toxicity no 71 4( a) Avian Reproduction Quail TGAI Degradates ABCJK ABCJK yes no 42547102 no reserved 71 4( b) Avian Reproduction Duck TGAI Degradates ABCJK ABCJK yes no 42547101 no reserved 71 5( a) Simulated Terrestrial Field Study no 71 5( b) Actual Terrestrial Field Study no 72 1( a) Acute Fish Toxicity Bluegill TGAI Major Degradate ABCJK ABCJK yes no 00024717 no yes 72 1( b) Acute Fish Toxicity Bluegill ( TEP)

72 1 © Acute Fish Toxicity Rainbow Trout TGAI Major Degradate ABCJK ABCJK yes no 00024716 no yes 72 1( d) Acute Fish Toxicity Rainbow Trout ( TEP) Date: November 2000 PHASE IV Case No: DATA REQUIREMENTS FOR Chemical No: 080803 ECOLOGICAL EFFECTS BRANCH Data Requirements Composition1 Use Pattern2 Does EPA Have Data To Satisfy This Requirement?

( Yes, No) Bibliographic Citation ( MRID) Must Additional Data Be Submitted under FIFRA3( c)( 2)( B)?

* In Bibliographic Citation column indicates study may be upgradeable XIII  4 72 2( a) Acute Aquatic Invertebrate Toxicity TGAI Major Degradate ABCJK ABCJK yes no 00024377 no yes 72 2( b) Acute Aquatic Invertebrate Toxicity ( TEP)

72 3( a) Acute Estu/ Mari Tox Fish TGAI Major Degradate ABCJK ABCJK yes no 43344901 no yes 72 3( b) Acute Estu/ Mari Tox Mollusk TGAI Major Degradate ABCJK ABCJK no no yes yes 72 3 © Acute Estu. Mari Tox Shrimp TGAI Major Degradate ABCJK ABCJK yes no 43344902 no yes 72 3( d) Acute Estu/ Mari Tox Fish ( TEP)

72 3( e) Acute Estu/ Mari Tox Mollusk ( TEP)

72 3( f) Acute Estu/ Mari Tox Shrimp ( TEP)

72 4( a) Early Life Stage Fish ( Freshwater) TGAI Major Degradate ABCJK ABCJK no no 45208304 no reserved 72 4( a) Early Life Stage Fish ( Marine) TGAI ABCJK no 45202920 * yes 72 4( b) Life Cycle Aquatic Invertebrate TGAI Major Degradate ABCJK ABCJK yes no 00024377 no reserved 72 4( b) Life Cycle Marine Invertebrate TGAI Major Degradate ABCJK ABCJK no no 45202920 * yes reserved 72 5 Life Cycle Fish TGAI Major Degradate ABCJK ABCJK yes no 00024377 no reserved 72 6 Aquatic Org. Accumulation 72 7( a) Simulated Aquatic Field Study 72 7( b) Actual Aquatic Field Study Date: November 2000 PHASE IV Case No: DATA REQUIREMENTS FOR Chemical No: 080803 ECOLOGICAL EFFECTS BRANCH Data Requirements Composition1 Use Pattern2 Does EPA Have Data To Satisfy This Requirement?

( Yes, No) Bibliographic Citation ( MRID) Must Additional Data Be Submitted under FIFRA3( c)( 2)( B)?

* In Bibliographic Citation column indicates study may be upgradeable XIII  5 122 1( a) Seed Germ./ Seedling Emerg. TEP 122 1( b) Vegetative Vigor TEP 122 2 Aquatic Plant Growth 123 1( a) Seed Germ./ Seedling Emerg. TEP ABCJK yes 42041403 no 123 1( b) Vegetative Vigor TEP ABCJK yes 42041402 no 123 2 Aquatic Plant Growth TGAI ABCJK yes 41065203a 41065203b 43074801 43074802 43074803 no 124 1 Terrestrial Field Study 124 2 Aquatic Field Study 141 1 Honey Bee Acute Contact TGAI ABCJK yes 00036935 no 141 2 Honey Bee Residue on Foliage TEP no no 141 5 Field Test for Pollinators TEP no no 1 Composition: TGAI= Technical grade of the active ingredient; PAIRA= Pure active ingredient, radiolabeled; TEP= Typical end use product 2 Use Patterns: A= Terrestrial Food Crop; B= Terrestrial Feed Crop; C= Terrestrial Non Food Crop; D= Aquatic Food Crop; E= Aquatic Non

Food Outdoor; F= Aquatic Non Food Industrial; G= Aquatic Non food Residential; H= Greenhouse Food Crop; I= Greenhouse Non

Food Crop; J= Forestry; K= Outdoor Recreation; L= Indoor Food; M= Indoor Non Food; N= Indoor Medical; O= Indoor Residential; Z= Use Group for Site 00000