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Human Health Water Quality Criteria and Methods for Toxics

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Pollutants can harm people’s health when they drink water or eat seafood from contaminated surface water. EPA scientists research how much of a specific chemical can be present in surface water before it is likely to harm human health. Based on this research, EPA develops human health criteria.

2015 EPA Updated Ambient Water Quality Criteria for the Protection of Human Health

EPA updated its national recommended water quality criteria for human health for 94 chemical pollutants to reflect the latest scientific information and EPA policies, including updated fish consumption rate, body weight, drinking water intake, health toxicity values, bioaccumulation factors, and relative source contributions. EPA accepted written comments from the public on the draft updated human health criteria from May to August 2014 and prepared responses to those comments. EPA water quality criteria provide recommendations to states and tribes authorized to establish water quality standards under the Clean Water Act.

2002 National Recommended Human Health Criteria

In 2002 EPA published an updated compilation of its national recommended water quality criteria for 158 pollutants. EPA water quality criteria provide recommendations to states and tribes authorized to establish water quality standards under the Clean Water Act. Additionally, EPA developed a criteria calculation matrix which provides: cancer potency factors, reference doses, relative source contributions, fish intake values, and equations used to derive the 2002 human health criteria.

2000 EPA Methodology for Deriving Ambient Water Quality Criteria for the Protection of Human Health

EPA’s Methodology for Deriving Ambient Water Quality Criteria for the Protection of Human Health is used in the development of EPA’s recommended criteria and offered as guidance for states and tribes in developing their own criteria.

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