Where It Comes From
Runoff or leaching from treated fields, orchards, vineyards, nurseries, and turf/rights‑of‑way [2].
How You Are Exposed
Drinking contaminated water (especially private wells in farm areas); mixing/applying at work; spray drift or contact with recently treated areas; small amounts on food [1][2].
Why It Matters
EPA sets a 4 ppb drinking water limit to protect health [1]. Animal studies show endocrine/reproductive effects; human cancer evidence is inadequate (IARC Group 3) [3][4].
Who Is at Risk
Farmworkers and applicators; people using untreated private wells near treated land; pregnant people, fetuses, and young children may be more sensitive [2][3].
How to Lower Your Exposure
Check your water system’s Consumer Confidence Report; test private wells if near agriculture; use certified activated carbon (NSF/ANSI 53) or reverse osmosis (NSF/ANSI 58) filters to reduce triazines; follow label and PPE at work; keep kids and pets off treated areas until reentry times [1][2][5].
References
- [1]U.S. EPA. National Primary Drinking Water Regulations – Table of Regulated Drinking Water Contaminants (Simazine MCL 0.004 mg/L).
- [2]U.S. EPA. Simazine: Reregistration Eligibility Decision (RED). Office of Pesticide Programs, 2006.
- [3]U.S. EPA. Triazine Cumulative Human Health Risk Assessment: Atrazine, Simazine, and Propazine. Office of Pesticide Programs, 2018.
- [4]IARC. Agents Classified by the IARC Monographs: Simazine (Group 3 – not classifiable).
- [5]U.S. EPA. Home Drinking Water Treatment/Point‑of‑Use Treatment Options (GAC and RO; NSF/ANSI 53 and 58).