Advanced testing methods now allow pesticides to be detected in water at very low levels. These small amounts of pesticides detected in drinking water or source water for drinking water do not necessarily indicate a health risk. The EPA has developed human health benchmarks for 363 pesticides to enable our partners to better determine whether the detection of a pesticide in drinking water or source waters for drinking water may indicate a potential health risk and to help them prioritize monitoring efforts. The table below includes benchmarks for acute (one-day) and chronic (lifetime) exposures for the most sensitive populations from exposure to pesticides that may be found in surface or ground water sources of drinking water. The table also includes benchmarks for 40 pesticides in drinking water that have the potential for cancer risk. The HHBP table includes pesticide active ingredients for which Health Advisories or enforceable National Primary Drinking Water Regulations (e.g., maximum contaminant levels) have not been developed.

A drinking water method for seven pesticides and pesticide degradates was developed that addresses the occurrence monitoring needs of the U.S. Environmental Protection Agency (EPA) for a future Unregulated Contaminant Monitoring Regulation (UCMR). The method employs on-line solid phase extraction-liquid chromatography/tandem mass spectrometry (SPE-LC/MS/MS). On-line SPE-LC/MS/MS has the potential to offer cost-effective, faster, more sensitive, and more rugged methods than the traditional off-line SPE approach due to complete automation of the SPE process, as well as seamless integration with the LC/MS/MS system. Multi-laboratory data are presented that demonstrate method ruggedness and transferability. The final method meets all of the EPA’s UCMR survey requirements for sample collection and storage, precision, accuracy, and sensitivity. This dataset is associated with the following publication: Shoemaker , J. Development and Multi-laboratory Verification of US EPA Method 543 for the Analysis of Drinking Water Contaminants by Online Solid Phase Extraction-LC–MS-MS. Journal of Chromatographic Science. Preston Publications Incorporated, Niles, IL, USA, 54(9): 1532-1539, (2016).

A drinking water method for seven pesticides and pesticide degradates was developed that addresses the occurrence monitoring needs of the U.S. Environmental Protection Agency (EPA) for a future Unregulated Contaminant Monitoring Regulation (UCMR). The method employs on-line solid phase extraction-liquid chromatography/tandem mass spectrometry (SPE-LC/MS/MS). On-line SPE-LC/MS/MS has the potential to offer cost-effective, faster, more sensitive, and more rugged methods than the traditional off-line SPE approach due to complete automation of the SPE process, as well as seamless integration with the LC/MS/MS system. Multi-laboratory data are presented that demonstrate method ruggedness and transferability. The final method meets all of the EPA’s UCMR survey requirements for sample collection and storage, precision, accuracy, and sensitivity. This dataset is associated with the following publication: Shoemaker , J. Development and Multi-laboratory Verification of US EPA Method 543 for the Analysis of Drinking Water Contaminants by Online Solid Phase Extraction-LC–MS-MS. Journal of Chromatographic Science. Preston Publications Incorporated, Niles, IL, USA, 54(9): 1532-1539, (2016).

The tabular data tables in this product include detection frequency and benchmark exceedances of agricultural pesticides in surface water samples collected in rivers and streams. The data are a product of a national-scale assessment of the toxicity of 221 pesticides at 74 sites during water years 2013 - 2017 conducted by the U.S. Geological Survey National Water Quality Pesticide Monitoring Program. Data were collected to 1) determine where and how often pesticides are detected in surface waters, and 2) identify regions in the continental United States that had streams with a higher risk of potential pesticide toxicity by comparing concentrations to both aquatic-life and human-health benchmarks.