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National Drinking Water Database


National Drinking Water Database - Chemical Contaminants

Methoxychlor


Status: Regulated - EPA has established a maximum legal limit in tapwater for this contaminant.

Methoxychlor is an endocrine-disrupting insecticide similar to DDT; banned in the U.S. in 2002, it was historically used on farm animals and in animal feed, lumber, gardens and certain crops. [read more]

 
Detected
Found above
health guidelines
Found above
legal limit
States
16
-
-
Water utilities
43
-
-
People Served
517,899
-
-

Health Concerns for Methoxychlor:


Methoxychlor Exposure by State

Water utilities in 16 states have reported detecting Methoxychlor in treated tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies.

StateWater Suppliers with Methoxychlor contamination
SystemsPopulation
Delaware1201,000
Illinois16161,904
Connecticut339,897
Kentucky134,650
Maryland529,505
Massachusetts115,853
Florida29,820
Indiana25,970
New Hampshire25,281
Arkansas23,499
Wisconsin13,308
California12,772
Iowa32,541
Missouri11,011
New York1800
North Carolina188
Total43517,899

The Most Polluted Communities

43 water utilities reported detecting Methoxychlor in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies

Ranked by highest average Methoxychlor level

RankSystem Population Served Positive test results of total reported tests Average Level
(Range)
1Manchester Park
Elkton, MD
4001 of 20.45 ppb
(0 to 0.9 ppb)
2Mathersville
Mathersville, IL
7791 of 20.42 ppb
(0 to 0.84 ppb)
3Rutland Water Supply
Whittemore, IA
1451 of 10.4 ppb
(0.4 ppb)
4Town of Hancock
Hancock, MD
1,9211 of 30.37 ppb
(0 to 1.1 ppb)
5Lost Hills Utility District
Lost Hills, CA
2,7721 of 20.22 ppb
(0 to 0.44 ppb)
6Leon Water Supply
Leon, IA
2,0461 of 10.2 ppb
(0.2 ppb)
7Luke / Newpage Luke Mill
Luke, MD
1843 of 110.13 ppb
(0 to 0.5 ppb)
8Corwith Water Supply
Corwith, IA
3501 of 10.1 ppb
(0.1 ppb)
9Jasper
Jasper, MO
1,0111 of 20.09 ppb
(0 to 0.17 ppb)
10Newmarket Water Works
Newmarket, NH
5,0001 of 50.08 ppb
(0 to 0.4 ppb)

Health Based Limits for Methoxychlor

StandardDescriptionLevel
California Public Health GoalsDefined by the State of California Office of Environmental Health Hazard Assessment (OEHHA) as the level of contaminant that is allowed in drinking water. For acutely toxic substances, levels are set at which scientific evidence indicates that no known or anticipated adverse effects on health will occur, plus an adequate margin-of safety. PHGs for carcinogens or other substances which can cause chronic disease shall be based solely on health effects without regard to cost impacts and shall be set at levels which OEHHA has determined do not pose any significant risk to health.30 ppb
Maximum Contaminant Limit (MCL)The enforceable standard which defines the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to health-based limits (Maximum Contaminant Level Goals, or MCLGs) as feasible using the best available analytical and treatment technologies and taking cost into consideration. Source: U.S. Environmental Protection Agency.40 ppb
Maximum Contaminant Limit Goal (MCLG)A non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.40 ppb
Lifetime health-based limit, non-cancer riskConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for a lifetime of exposure. The Lifetime health-based limit (or Health Advisory, HA) is based on exposure for a a 70-kg adult consuming 2 liters of water per day. Source: U.S. Environmental Protection Agency.40 ppb
Children's health-based limit for 1-day exposureConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for up to one day of exposure. The One-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.50 ppb
Children's health-based limit for 10-day exposureConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic effects for up to ten days of exposure. The Ten-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.50 ppb
EPA Human Health Water Quality CriteriaWater quality criteria set by the US EPA provide guidance for states and tribes authorized to establish water quality standards under the Clean Water Act (CWA) to protect human health. These are non-enforceable standards based upon exposure by both drinking water and the contribution of water contamination to other consumed foods. Source: U.S. Environmental Protection Agency.100 ppb
Drinking Water Equivalent LevelA lifetime exposure concentration protective of adverse, noncarcinogenic health effects, that assumes all of the exposure to a contaminant is from drinking water. Source: U.S. Environmental Protection Agency.200 ppb

Testing Summary for Methoxychlor

Are tests routinely required for Methoxychlor by federal law?Yes
Water suppliers reporting tests for Methoxychlor (2004-2009):20,503 of 47,576
Average testing rate for water supplier reporting tests (2004-2009):0.4 per year

Violation Summary for Methoxychlor

Data from the U.S. Environmental Protection Agency includes the following violations of federal standards for Methoxychlor since 2004

Maximum Contaminant Level Exceedance Violations0
Monitoring Violations1,801
Reporting Violations0

Occupational hazards

Type of concern: Reference:
Allowed workplace exposures restricted to moderate doses RTECS®- TLV/BEI,2007

Cancer

Type of concern: Reference:
One or more in vitro tests on mammalian cells show positive mutation results RTECS®- Reproductive Toxicology 2003
One or more in vitro tests on mammalian cells show positive mutation results RTECS®- Archives of Toxicology 1986
One or more in vitro tests on mammalian cells show positive mutation results RTECS®- Mutation Research 1996
One or more in vitro tests on mammalian cells show positive mutation results RTECS®- Folia Morphologica (Warsaw) 1976
One or more in vitro tests on mammalian cells show positive mutation results RTECS®- JNCI, Journal of the National Cancer Institute 1981
One or more in vitro tests on mammalian cells show positive mutation results RTECS®- Environmental and Molecular Mutagenesis 1988
One or more in vitro tests on mammalian cells show positive mutation results RTECS®- Proceedings of the Society for Experimental Biology and Medicine 1984
One or more in vitro tests on mammalian cells show positive mutation results RTECS®- Environmental and Molecular Mutagenesis 1994



Government, industry, academic studies and classifications

government/industry list/academic study appears on list as classification(s)
RTECS®- TLV/BEI,2007ETHANE, 1,1,1-TRICHLORO-2,2-BIS(P-METHOXYPHENYL)-• occupationally related - ACGIH TLV (human TWA)
RTECS®- Archives of Toxicology 1986ETHANE, 1,1,1-TRICHLORO-2,2-BIS(P-METHOXYPHENYL)-• mutagenic - Positive mutation assay: Cytogenetic Analysis (hamster ipr)
RTECS®- Environmental and Molecular Mutagenesis 1988ETHANE, 1,1,1-TRICHLORO-2,2-BIS(P-METHOXYPHENYL)-• mutagenic - Positive mutation assay: Mutation in Micro-organism (mouse lym)
RTECS®- Environmental and Molecular Mutagenesis 1994ETHANE, 1,1,1-TRICHLORO-2,2-BIS(P-METHOXYPHENYL)-• mutagenic - Positive mutation assay: DNA Damage (rat lvr)
RTECS®- Folia Morphologica (Warsaw) 1976ETHANE, 1,1,1-TRICHLORO-2,2-BIS(P-METHOXYPHENYL)-• mutagenic - Positive mutation assay: Cytogenetic Analysis (mouse orl)
RTECS®- JNCI, Journal of the National Cancer Institute 1981ETHANE, 1,1,1-TRICHLORO-2,2-BIS(P-METHOXYPHENYL)-• mutagenic - Positive mutation assay: Morphological Transform (mouse fbr)
RTECS®- Mutation Research 1996ETHANE, 1,1,1-TRICHLORO-2,2-BIS(P-METHOXYPHENYL)-• mutagenic - Positive mutation assay: Morphological Transform (hamster emb)
RTECS®- Proceedings of the Society for Experimental Biology and Medicine 1984ETHANE, 1,1,1-TRICHLORO-2,2-BIS(P-METHOXYPHENYL)-• mutagenic - Positive mutation assay: sperm (rat orl)
RTECS®- Reproductive Toxicology 2003ETHANE, 1,1,1-TRICHLORO-2,2-BIS(P-METHOXYPHENYL)-• mutagenic - Positive mutation assay: Micronucleus test (mouse scu)



references

government/industry list/academic study reference
RTECS®- TLV/BEI,2007RTECS®- TLV/BEI,2007
RTECS®- Archives of Toxicology 1986RTECS®- Archives of Toxicology. (Springer-Verlag, Heidelberger Pl. 3, D-1000 Berlin 33, Fed. Rep. Ger.) V.32- 58,152,1986
RTECS®- Environmental and Molecular Mutagenesis 1988RTECS®- Environmental and Molecular Mutagenesis. (Alan R. Liss, Inc., 41 E. 11th St., New York, NY 10003) V.10- 12(Suppl 13),103,1988
RTECS®- Environmental and Molecular Mutagenesis 1994RTECS®- Environmental and Molecular Mutagenesis. (Alan R. Liss, Inc., 41 E. 11th St., New York, NY 10003) V.10- 24,181,1994
RTECS®- Folia Morphologica (Warsaw) 1976RTECS®- Folia Morphologica (Warsaw). (Panstwowy Zaklad Wydawnictw Lekarskich, ul. Dluga 38-40, 00 238 Warsaw, Poland) V.1- 35,361,1976
RTECS®- JNCI, Journal of the National Cancer Institute 1981RTECS®- JNCI, Journal of the National Cancer Institute. (Washington, DC) V.61-79, 1978-87. For publisher information, see JNCIEQ. 67,1303,1981
RTECS®- Mutation Research 1996RTECS®- Mutation Research. (Elsevier Science Pub. B.V., POB 211, 1000 AE Amsterdam, Netherlands) V.1- 356,85,1996
RTECS®- Proceedings of the Society for Experimental Biology and Medicine 1984RTECS®- Proceedings of the Society for Experimental Biology and Medicine. (Academic Press, Inc., 1 E. First St., Duluth, MN 55802) V.1- 176,187,1984
RTECS®- Reproductive Toxicology 2003RTECS®- Reproductive Toxicology. (Pergamon Press Inc., Maxwell House, Fairview Park, Elmsford, NY 10523) V.1- 17,79,2003

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