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Drinking Water Contaminant Human Health Effects Information

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Drinking Water Standards and Advisory Tables

These tables summarize EPA's drinking water regulations and health advisory as well as reference dose (RFD) and cancer risk values for drinking water contaminants. EPA updates the tables periodically.

The tables contain drinking water standards in the form of non-enforceable concentrations of drinking water contaminants, or Maximum Contaminant Level Goals (MCLGs), as well as enforceable Maximum Contaminant Levels (MCLs). Maximum Contaminant Levels are the maximum permissible level of a contaminant in water delivered to users of a public water system.

Health Advisories (HAs) provide information on contaminants that can cause human health effects and are known or anticipated to occur in drinking water. EPA's HAs are non-enforceable and provide technical guidance to states agencies and other public health officials on health effects, analytical methodologies, and treatment technologies associated with drinking water contamination. The tables contain HA values for certain contaminants based on non-cancer health effects for different durations of exposure (for example, one-day, ten-day, and lifetime).


Human Health Benchmarks for Pesticides

EPA has developed human health benchmarks for approximately 394 pesticides to help states, tribes and water systems better understand whether pesticides they may detect in drinking water or sources of drinking water may present a public health risk.  HHBPs are non-enforceable and non-regulatory.


Human Health and Drinking Water Advisory Documents for Chemical Contaminants

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Regulatory Support Documents for Chemical Contaminants

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Human Health Drinking Water Advisory/Effects Documents for Microbial Contaminants

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