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Office of Pesticide Programs' Aquatic Life Benchmarks
On this page
- Introduction
- Relationship to Ambient Water Quality Criteria
- Use of Aquatic Life Benchmarks
- OPP Aquatic Life Benchmarks
- Footnotes
- Definitions
- References
Introduction
The aquatic life benchmarks (for freshwater species) provided in the table below are based on toxicity values reviewed by EPA and used in the Agency's most recent risk assessments developed as part of the decision-making process for pesticide registration. The Office of Pesticide Programs (OPP) in EPA relies on studies required under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as specified at 40 CFR Part 158, as well as a wide range of environmental laboratory and field studies available in the public scientific literature to assess environmental risk. Each Aquatic Life Benchmark is based on the most sensitive, scientifically acceptable toxicity endpoint available to EPA for a given taxon (for example, freshwater fish) of all scientifically acceptable toxicity data available to EPA. EPA's goal is to add to these benchmarks annually.
Relationship to Ambient Water Quality Criteria
Both OPP and EPA's Office of Water (OW) have responsibilities for evaluating aquatic toxicity data to assess the ecological effects of chemicals in surface water. Effects assessments under both program offices are developed with high quality data pursuant to parallel but somewhat different rigorously peer-reviewed assessment methods.
OW uses aquatic toxicity data to develop ambient water quality criteria that can be adopted by states and tribes to establish water quality standards under the Clean Water Act. Criteria are available for roughly 16 pesticides. Procedures for deriving the criteria are described in Guidelinesa , and require, for acute criteria, that data be available for at least 8 families.
OPP uses aquatic toxicity data in ecological risk assessments for large numbers of pesticide registration decisions under FIFRA. OPP's procedures for effects assessment are described in the Overview Document b; and rely, at a minimum, on data for the most sensitive tested effects concentration for each taxon.
Both the OW and OPP methods assess and characterize effects to protect aquatic communities.
The table below provides aquatic toxicity benchmarks, a reference for the most recent risk assessment conducted by OPP for each pesticide, and ambient water quality criteria, if available.
Use of Aquatic Life Benchmarks
EPA worked initially with the USGS to identify aquatic ecotoxicity benchmarks values from risk assessments developed by EPA for individual pesticides during the recently completed re-registration program. The Overview Document and ecological risk assessments developed for individual pesticides provide useful information for understanding how these ecotoxicity benchmarks were developed and the uncertainties associated with each benchmark. Comparing a measured concentration of a pesticide in water with an aquatic life benchmark can be helpful in interpreting monitoring data, and to identify and prioritize sites and pesticides that may require further investigation.
These aquatic benchmarks are extracted from the most recent publically available OPP risk assessment for the pesticide and are based on the most sensitive aquatic toxicity data of the distribution for each taxa. Benchmarks, developed for baseline risk assessments, are estimates of the concentrations below which pesticides are not expected to harm aquatic life. OPP may further refine a risk assessment based on the full distribution of toxicity data for a given species, using point estimates, species sensitivity distribution approaches, or probabilistic methods.
OPP and OW are actively working together to harmonize the high quality, peer-reviewed scientific approaches that now underlie both programs. A harmonized approach will result in consistent tools and approaches for all stakeholder communities to use in ensuring the protection of aquatic ecosystems.
| Pesticide | CAS number | Fish | Invertebrates | Nonvascular Plants | Vascular Plants | Office of Water Aquatic Life Criteria |
|||
|---|---|---|---|---|---|---|---|---|---|
| Acute1 | Chronic2 | Acute3 | Chronic4 | Acute5 | Acute6 | Maximum Concentration (CMC) |
Continuous Concentration (CCC) |
||
| Acephate 9 | 30560191 | 416,000 | 5,760 | 550 | 150 | > 50,000 | — | — | — |
| Acetochlor | 34256821 | 190 | 130 | 4,100.0 | 22.10 | 1.43 | 3.40 | — | — |
| Acetochlor degradate Ethanesulfonic acid (ESA) 8 |
— | > 90,000 | — | > 62,500 | — | 9,900.00 | — | — | — |
| Acifluorfen | 62476599 | 15,500 | < 1,500 | 14,050 | — | > 265 | 189 | — | — |
| Acrolein 10, 13 | 107028 | 7 | 11.4 | < 15.5 | 7.1 | 28 | 72 | — | — |
| Alachlor | 15972608 | 900 | 187 | 1,600 | 110 | 1.64 | 2.3 | — | — |
| Alachlor degradate Ethane sulfonic acid |
187022113 | 52,000 | — | 52,000 | — | — | — | — | — |
| Alachlor degradate Oxanilic acid |
184992444 | 47,500 | — | 47,500 | — | — | — | — | — |
| Aldicarb 9 | 116063 | 26 | 0.46 | 10 | 1 | > 5,000 | — | — | |
| Aldicarb sulfoxide | 1646873 | 3,570 | — | 21.5 | — | — | — | — | — |
| Aldicarb sulfone | 21,000 | — | 140 | — | — | — | — | — | |
| Ametryn | 834128 | 1,800 | 700 | 14,000 | 240 | 3.67 | 10 | — | — |
| Atrazine 7 | 1912249 | 2,650 | 65 | 360 | 60 | 1 | 37 | — | — |
| Atrazine degradate HA 8 |
2163680 | > 1,500 | — | > 2,050 | — | > 10,000 | — | — | — |
| Atrazine degradate DACT 8 |
— | > 50,000 | — | > 50,000 | — | — | — | — | |
| Atrazine degradate DIA 8 |
— | 8,500 | — | > 63,000 | — | 2,500 | — | — | — |
| Atrazine degradate DEA |
— | — | — | — | — | 1,000 | — | — | — |
| Azinphos methyl 9 | 86500 | 0.18 | 0.055 | 0.08 | 0.036 | — | — | — | — |
| Azoxystrobin | 13860338 | 235 | 147 | 130 | 44 | 49 | 3,400 | — | — |
| Benfluralin 8 | 1861401 | 34.85 | 1.9 | 10,540 | 15.5 | > 100 | — | — | — |
| Bensulide 10 | 741582 | 360 | 374 | 290 | — | 1,500 | — | — | — |
| Bentazon 8 | 50723803 | > 50,000 | — | > 50,000 | — | 4,500 | 5,350 | — | — |
| Bromacil | 314409 | 18,000 | 3,000 | 60,500 | 8,200 | 6.8 | 45 | — | — |
| Butylate 10 | 2008415 | 105 | 210 | 5,950 | — | — | — | — | — |
| Carbaryl 9 | 63252 | 110 | 6.8 | 0.85 | 0.5 | 660 | 1,500 | — | — |
| Carbofuran | 1563662 | 44 | 5.7 | 1.115 | 0.75 | — | — | — | — |
| Carboxin | 5234684 | 600 | — | 42,200 | — | 370 | 670 | — | — |
| Captan 10 | 133062 | 13.1 | 16.5 | 4,200 | 560 | 320 | > 12700 | — | — |
| Clopyralid | 57754855 | 984,000 | — | 56,500 | — | — | — | — | — |
| Chloropicrin 13 | 76062 | < 8.49 | — | < 36 | — | — | — | — | — |
| Chlorothalonil | 1897456 | 5.25 | 3 | 1.8 | 0.6 | 6.8 | 630 | — | — |
| Chlorpyrifos | 2921882 | 0.9 | 0.57 | 0.05 | 0.04 | 140 | — | 0.083 | 0.041 |
| Coumaphos 10 | 56724 | 170 | 11.7 | 0.037 | 0.0337 | — | — | — | — |
| Cycloate | 1134232 | 2,250 | — | 1,300 | — | — | — | — | — |
| Cypermethrin | 52315078 | 0.195 | 0.14 | 0.21 | 0.069 | — | — | — | — |
| Dacthal (DCPA) 8 | 1861321 | 15,000 | — | 13,500 | — | > 11,000 | > 11,000 | — | — |
| 2,4-DB 11 | 94826 | 1,000 | — | 7,500 | — | 932 | — | — | — |
| 2,4-DB-DMAS 11 | — | 1,567 | — | 10,150 | — | — | — | — | — |
| Diazinon 10, 13 | 333415 | 45 | < 0.55 | 0.105 | 0.17 | 3,700 | — | 0.17 | 0.17 |
| Diazinon degradate Oxypyrimidine 8 | > 50,500 | — | > 51,000 | — | > 109,000 | — | — | — | |
| Dicamba 8, 11 | 1918009 | 14,000 | — | 17,300 | — | 61 | > 3,250 | — | — |
| Diclobenil 13 | 1194656 | 2,465 | < 330 | 1,850 | 560 | 1,000 | 30 | — | — |
| Dicrotophos | 141662 | 3,150 | — | 6.35 | 0.99 | — | — | — | — |
| Dimethenamid | 163515148 | 3,150 | 300 | 6,000 | 1,020 | 14 | 8.9 | — | — |
| Dimethoate 9 | 60515 | 3,100 | 430 | 21.5 | 0.5 | 84 | — | — | — |
| Disulfoton 9 | 298044 | 19.5 | 4 | 1.95 | 0.01 | — | — | — | — |
| Disulfoton sulfone | — | > 4,600 | — | 17.5 | 0.14 | — | — | — | — |
| Disulfoton sulfoxide 8 | — | 30,000 | — | 32 | 1.53 | — | — | — | — |
| Diuron 10 | 330541 | 355 | 26 | 80 | 160 | 2.4 | — | — | — |
| Endosulfan | 115297 | 0.42 | 0.11 | 2.9 | 0.07 | — | — | 0.22 | 0.056 |
| Endosulfan sulfate | 1031078 | 1.9 | — | — | — | — | — | — | — |
| EPTC | 759944 | 7,000 | — | 3,245 | 810 | 1,400 | 5,600 | — | — |
| Esfenvalerate 9 | 66230044 | 0.035 | 0.035 | 0.025 | 0.017 | — | — | — | — |
| Ethalfluralin | 55283686 | 16 | 0.4 | 30 | 24 | 25 | — | — | — |
| Ethoprop | 13194484 | 150 | 24 | 22 | 800 | 8,400 | — | — | — |
| Fenitrothion | 122145 | 860 | 46 | 1.15 | 0.087 | — | — | — | — |
| Fenthion 8 | 55389 | 415.0 | 7.5 | 2.60 | 0.013 | 400 | > 2,800 | — | — |
| Fluometuron | 2164172 | 320 | — | 110 | — | 30 | 220 | — | — |
| Glyphosate 10 | 1071836 | 21,500 | 1,800 | 26,600 | 49,900 | 12,100 | 11,900 | — | — |
| Glyphosate isopropylamine salt | 38641940 | 42,450 | — | — | — | — | — | — | — |
| Glyphosate degradate aminomethyl phosphoric acid (AMPA) |
249,500 | — | 341,500 | — | — | — | — | — | |
| Hexazinone | 51235042 | 137,000 | 17,000 | 75,800 | 20,000 | 7 | 37.4 | — | — |
| Imazapyr 8, 10 | 81334341 | > 50,000 | 43,100 | 50,000 | 97,100 | 11,500 | 18 | — | — |
| Imazamox 8 | 114311329 | > 59,500 | — | > 61,000 | — | > 40 | 11 | — | — |
| Imidacloprid 8 | 105827789 | > 41,500 | 1,200 | 35 | 1.05 | > 10,000 | — | — | — |
| Iprodione 8, 10 | 36734197 | 1,550 | 260 | 120 | 170 | 330 | > 12,640 | — | — |
| Isoxaflutole 8 | 141112290 | > 850 | — | > 750 | — | 110 | 4.9 | — | — |
| Isoxaflutole - rpa202248 8 | — | > 15,300 | — | > 29,800 | — | 5,000 | 75 | — | — |
| Lindane (gamma HCH) | 58899 | 0.850 | 2.9 | 0.500 | 54 | — | — | 0.95 | — |
| Linuron 9 | 330552 | 1,500 | 5.58 | 60 | 0.09 | 13.7 | 2.5 | — | — |
| Malathion 9 | 121755 | 0.295 | 0.014 | 0.005 | 0.000026 | 2,040 | 24,065 | — | — |
| Mancozeb | 8018017 | 230 | — | 290 | — | 47 | — | — | — |
| Maneb | 12427382 | 21 | — | 60 | — | 13.4 | — | — | — |
| Mancozeb and Maneb degradate ETU 8 | — | > 251,000 | 37,320 | 134,500 | 2 | — | — | — | — |
| MCPA acid 11 | 94746 | — | — | — | — | 300 | 170 | — | — |
| MCPA sodium salt 8, 11 | — | > 34,000 | — | > 92,000 | — | — | — | — | — |
| MCPA DMAS 11 | — | 48,000 | 12,000 | 41,000 | 11,000 | 160 | 130 | — | — |
| MCPA EHE 11 | — | 380 | — | 90 | — | 170 | 20 | — | — |
| MCPB | 6062266 | 1,950 | — | 25,000 | — | 380 | 210 | — | — |
| MCPP-p acid 10 | 16484778 | — | — | > 45,500 | 50,800 | — | — | — | — |
| MCPP-p DMAS 8 | 6642394 | > 46,500 | — | — | — | 14 | 1,300 | — | — |
| Metam sodium | 137428 | 25.6 | — | 27.5 | 254 | 590 | — | — | |
| Metalaxyl 8 | 57837191 | 65,000 | > 9,100 | 6,250 | 1,200 | 140,000 | 85,000 | — | — |
| Mefanoxam 8 | 70630170 | > 60,500 | — | 14,000 | — | — | 77,000 | — | — |
| Methamidophos 8, 9 | 10265926 | 12,500 | 48.9 | 13 | 4.5 | > 50,000 | — | — | — |
| Methidathion 10 | 950378 | 1.1 | 6.1 | 1.5 | 0.66 | — | — | — | — |
| Methomyl 9 | 16752775 | 160 | 12 | 2.5 | 0.7 | — | — | — | — |
| Methiocarb | 2032657 | 218 | 50 | 3.5 | 0.1 | — | — | — | — |
| Metribuzin | 21087649 | 21,000 | 3,000 | 2,100 | 1.29 | 8.7 | 130 | — | — |
| Methoprene | 40596698 | 380 | 48 | 165 | 51 | — | — | — | — |
| Methyl bromide | 74839 | 1,950 | 100 | 1,300 | — | 2,200 | — | — | — |
| Methyl parathion 13 | 298000 | 925 | < 10 | 0.485 | 0.25 | 15,000 | 18,000 | — | — |
| Methyl paraoxon | 950356 | — | — | 1.15 | 1 | — | — | — | — |
| Metolachlor | 51218452 | 1,600 | 1,000 | 550 | 1 | 8 | 21 | — | — |
| Metolachlor OA8 | — | > 46,550 | — | 7,700 | — | 57,100 | > 95,100 | — | — |
| Metolachlor ESA 8 | — | 24,000 | — | > 54,000 | — | > 99,450 | > 95,100 | — | — |
| Molinate 10 | 2212671 | 105 | 390 | 170 | 340 | 220 | 3,300 | — | — |
| Naled | 300765 | 46 | 2.9 | — | 0.045 | 25 | > 1,800 | — | — |
| Naled DDVP | — | 50 | 5.2 | 0.033 | 0.0058 | — | — | — | — |
| Napropamide | 15299997 | 3,200 | 1,100 | 7,150 | 1,100 | 3,400 | — | — | — |
| Norflurazon 8 | 27314132 | 4,050 | 770 | > 750 | 1,000 | 9.7 | 58.2 | — | — |
| Oxydemeton methyl 8, 9 | 301122 | 365 | 5 | 95 | 46 | > 100,000 | — | — | — |
| Oxyfluorfen | 42874033 | 101.5 | 1.3 | 40 | 13 | 0.29 | 0.35 | — | — |
| Oryzalin 8 | 19044883 | 1,440 | 220 | 750 | 358 | 42 | > 15.4 | — | — |
| Oxamyl 10 | 23135220 | 2,100 | 770 | 90 | 180 | 120 | 30,000 | — | — |
| Pebulate | 1114712 | 3,150 | — | 3,315 | — | 230 | 1,800 | — | — |
| Pendimethalin | 40487421 | 69 | 6.3 | 140 | 14.5 | 5.4 | 12.5 | — | — |
| Permethrin 16 | 52645531 | 0.395 | 0.0515 | 0.0106 | 0.0014 | 68 | — | — | — |
| Phorate 8 | 298022 | 1.175 | 0.34 | 0.3 | 0.21 | > 1,300 | — | — | — |
| Phosmet 8 | 732116 | 35 | 3.2 | 1.0000 | 0.8 | 34 | > 1,800 | — | — |
| Picloram | 1918021 | 6,500 | 550 | 34,150 | 11,800 | 4,900 | — | — | — |
| Pinoxaden | 243973208 | 10,000 | — | — | — | 1,200 | 4,300 | — | — |
| Pinoxaden (NOA 497854) 8 | — | > 51,500 | > 960 | > 50,500 | 5,800 | > 100,000 | 10,000 | — | — |
| Pinoxaden (NOA 447204) 8 | — | > 60,000 | — | > 60,000 | — | 95,600 | > 93,500 | — | — |
| Profenofos | 41198087 | 7.05 | 2 | 0.465 | 0.2 | — | — | — | — |
| Prometon 10 | 1610180 | 6,000 | 9,500 | 12,850 | 3,500 | 98 | 624 | — | — |
| Prometryn | 7287196 | 1,450 | — | 9,295 | 1,000 | 1 | 11.8 | — | — |
| Propachlor | 1918167 | 85 | — | 395 | — | 13.5 | — | — | — |
| Propanil | 709988 | 1,150 | 9.1 | 600 | 86 | 16 | 110 | — | — |
| Propargite | 2312358 | 59 | 16 | 37 | 9 | 66.2 | 75,000 | — | — |
| Propetamphos | 31218834 | 94 | — | 1.65 | — | — | — | — | — |
| Propiconazole | 60207901 | 425 | 95 | 2,400 | — | 93 | 4,828 | — | — |
| Propoxur | 114261 | 1,850 | — | 5.5 | — | — | — | — | — |
| Propyzamide 8, 9 | 23950585 | 36,000 | 7,700 | > 2,800 | 600 | > 4,000 | 1,180 | — | — |
| Resmethrin | 10453868 | 0.14 | 0.32 | 1.550 | — | — | — | — | — |
| Rotenone 10 | 83794 | 0.97 | 1.01 | 1.850 | 1.25 | — | — | — | — |
| Simazine | 122349 | 3,200 | 960 | 500 | 2,000 | 36 | 140 | — | — |
| Sulfosulfuron 8 | 141776321 | > 45,000 | 100,000 | > 48,000 | 102,000 | 400 | 1 | — | — |
| Tebuthiuron | 34014181 | 53,000 | 9,300 | 148,500 | 21,800 | 50 | 135 | — | — |
| Telone | 542756 | 540 | — | 45 | 70 | 7,900 | 20,000 | — | — |
| Telone degradate 3-chloroacrylic acid |
— | 34,750 | — | 27,500 | — | 430 | 220 | — | — |
| Telone degradate 3-chloroallyl alcohol |
— | 493 | — | 1,150 | — | 32,900 | 1,694 | — | — |
| Temephos | 3383968 | 1,745 | — | 5 | — | — | — | — | — |
| Terbacil | 5902512 | 23,100 | 1,200 | 32,500 | 640 | 11 | 140 | — | — |
| Terbufos 10 | 13071799 | 0.385 | 0.64 | 0.1 | 0.03 | — | — | — | — |
| Thiobencarb | 28249776 | 280 | — | 50 | 1 | 17 | 770 | — | — |
| Thiram 10 | 137268 | 21 | 530 | 105 | 170.6 | 140 | 1,600 | — | — |
| Tralkoxydim 8 | 87820880 | > 3,750 | — | > 87,000 | 2,100 | 7,700 | 2,600 | — | — |
| Triallate | 2303175 | 600 | 38 | 45.5 | 13 | 120 | 2,400 | — | — |
| Triasulfuron 8, 10 | 82097505 | > 50,000 | 68,600 | > 50,000 | 105,000 | — | — | — | — |
| Tribufos | 78488 | 122.5 | 3.5 | 13.5 | 1.56 | 148 | 1,100 | — | — |
| Triclopyr 14 | 55335063 | 180 | 104,000 | 850 | 80,700 | 100 | 880 | — | — |
| Trifluralin | 1582098 | 20.5 | 1.14 | 280 | 2.4 | 7.52 | 43.5 | — | — |
| Ziram 10 | 137304 | 9.7 | 101 | 24 | 39 | 67 | 370 | — | — |
Footnotes
1 Benchmark = Toxicity value x LOC. For acute fish, toxicity value is generally the lowest 96-hour LC50 in a standardized test (usually with rainbow trout, fathead minnow, or bluegill), and the LOC is 0.5.
2 Benchmark = Toxicity value x LOC. For chronic fish, toxicity value is usually the lowest NOEAC from a life-cycle or early life stage test (usually with rainbow trout or fathead minnow), and the LOC is 1.
3 Benchmark = Toxicity value x LOC. For acute invertebrate, toxicity value is usually the lowest 48- or 96-hour EC50 or LC50 in a standardized test (usually with midge, scud, or daphnids), and the LOC is 0.5.
4 Benchmark = Toxicity value x LOC. For chronic invertebrates, toxicity value is usually the lowest NOAEC from a life-cycle test with invertebrates (usually with midge, scud, or daphnids), and the LOC is 1.
5 Benchmark = Toxicity value x LOC. For acute nonvascular plants, toxicity value is usually a short-term (less than 10 days) EC50 (usually with green algae or diatoms), and the LOC is 1.
6 Benchmark = Toxicity value x LOC. For acute vascular plants, toxicity value is usually a short-term (less than 10 days) EC50 (usually with duckweed) and the LOC is 1.
7 Chronic Aquatic Community Benchmark for Atrazine = 17.5 µg / L.
Exceedance of this benchmark concentration, as an average for any 60-day period, could cause community-level effects based on changes in plant community diversity and indirect effects on fish and aquatic invertebrates.8 Because the underlying toxicity value is a "greater-than" value (such as >265,000), this benchmark may overestimate toxicity.
9 The chronic benchmark is based on the acute toxicity value (which was lower than the lowest available chronic toxicity value), and therefore may underestimate chronic toxicity.
10 Although the underlying acute toxicity value is greater than or equal to the chronic toxicity value, the acute benchmark is lower than the chronic benchmark because acute and chronic toxicity values were multiplied by LOC values of 0.5 and 1, respectively.
11 Original toxicity values are in micrograms of acid equivalents per liter. For 2,4-D and 2,4-DB, the toxicity values selected were the lowest available values for the acid or salt forms. For MCPA, acute toxicity values were the lowest for the acid, salt or ester forms, and chronic toxicity values were the lowest of the acid and salt forms. For Dicamba the toxicity values were the lowest of the acid or salt forms. (Selection was consistent with risk quotients in the cited USEPA references.)
13 Because the underlying toxicity value is a "less-than" value (such as <1,500), this benchmark may underestimate toxicity.
14 The acute toxicity values were the lowest of the acid, salt or ester forms, and the chronic toxicity values were the lowest of the acid and salt forms of triclopyr. (Selection was consistent with risk quotients in the cited USEPA reference.)
16 Toxicity values and benchmarks apply to permethrin. If monitoring data represent only the cis isomer of permethrin in water, comparison with benchmarks may underestimate potential toxicity.
Definitions
CCC = Criterion continuous concentration
CMC = Criterion maximum concentration
EC50 = 50 percent effect concentration
LC50 = 50 percent lethal concentration
LOC = level of concern
NOAEC = no-observed-adverse-effects concentration
µg/L = microgram per liter
— = no benchmark available
References
aStephan, C.E, D.I. Mount, D.J. Hanson, J.H. Gentile, G.A. Chapman, and W.A. Brungs. 1985. Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses. EPA PB85-227049.
bU.S. EPA. 2004. Overview of the Ecological Risk Assessment Process in the Office of Pesticide Programs. Office of Prevention, Pesticides, and Toxic Substances. Office of Pesticide Programs. Washington, D.C. January 23, 2004.