Pesticides and pesticide degradates in groundwater used for public supply across the United States: Occurrence and human-health context
Links
- More information: Publisher Index Page (via DOI)
- Open Access Version: Publisher Index Page
- Download citation as: RIS | Dublin Core
Abstract
This is the first assessment of groundwater from public-supply wells across the United States to analyze for >100 pesticide degradates and to provide human-health context for degradates without benchmarks. Samples from 1204 wells in aquifers representing 70% of the volume pumped for drinking supply were analyzed for 109 pesticides (active ingredients) and 116 degradates. Among the 41% of wells where pesticide compounds were detected, nearly two-thirds contained compound mixtures and three-quarters contained degradates. Atrazine, hexazinone, prometon, tebuthiuron, four atrazine degradates, and one metolachlor degradate were each detected in >5% of wells. Detection frequencies were largest for aquifers with more shallow, unconfined wells producing modern-age groundwater. To screen for potential human-health concerns, benchmark quotients (BQs) were calculated by dividing concentrations by the human-health benchmark, when available. For degradates without benchmarks, estimated values (estimated benchmark quotients (BQE)) were first calculated by assuming equimolar toxicity to the most toxic parent; final analysis excluded degradates with likely overestimated toxicity. Six pesticide compounds and 1.6% of wells had concentrations approaching levels of potential concern (individual or summed BQ or BQE values >0.1), and none exceeded these levels (values >1). Therefore, although pesticide compounds occurred frequently, concentrations were low, even accounting for mixtures and degradates without benchmarks.
Suggested Citation
Bexfield, L.M., Belitz, K., Lindsey, B.D., Toccalino, P., Nowell, L.H., 2021, Pesticides and pesticide degradates in groundwater used for public supply across the United States: Occurrence and human-health context: Environmental Science & Technology, v. 55, no. 16, p. 362-372, https://doi.org/10.1021/acs.est.0c05793.
ISSN: 1520-5851 (online)
Study Area
| Publication type | Article |
|---|---|
| Publication Subtype | Journal Article |
| Title | Pesticides and pesticide degradates in groundwater used for public supply across the United States: Occurrence and human-health context |
| Series title | Environmental Science & Technology |
| DOI | 10.1021/acs.est.0c05793 |
| Volume | 55 |
| Issue | 16 |
| Publication Date | December 14, 2020 |
| Year Published | 2021 |
| Language | English |
| Publisher | American Chemical Society |
| Contributing office(s) | WMA - Earth System Processes Division |
| Description | 11 p. |
| First page | 362 |
| Last page | 372 |
| Country | United States |
| Other Geospatial | Continental United States |