Lindane in Drinking Water: Complete Guide (2026)

What is Lindane and Why Does It Matter?

# Lindane in Your Tap Water: What You Need to Know

Lindane is a synthetic pesticide that was widely used in agriculture and as a treatment for lice and scabies throughout the 20th century. Once applied to crops or soil, lindane persists in the environment for decades—it breaks down extremely slowly, which scientists call high persistence. The chemical enters groundwater when it leaches through soil after application, and it can also contaminate surface water through agricultural runoff. Even though the EPA banned most uses of lindane in the United States in 2006, it remains in the environment and continues to show up in water systems. Some older pesticide stockpiles and contaminated sites still release lindane into groundwater, keeping it a concern for water utilities.

Our analysis found lindane in 28 water systems across the country, with an average concentration of 0.009 parts per billion (ppb). One system in Florida exceeded safe guidelines at 0.117 ppb—more than 13 times higher than the average detected level. While this is a relatively small number of affected systems, even low-level exposure matters because lindane accumulates in body fat over time. The EPA classifies lindane as a probable human carcinogen, meaning prolonged exposure increases cancer risk. Studies also link lindane to reproductive harm, developmental problems in children, and damage to the nervous system. The World Health Organization has documented that chronic exposure affects hormone regulation and immune function.

The EPA's legal drinking water limit for lindane is 0.2 ppb, but the Environmental Working Group (EWG) recommends a stricter health guideline of 0.013 ppb based on cancer risk assessments. This means the one system that tested at 0.117 ppb exceeds the EPA standard but falls below what EWG considers truly safe for long-term consumption. The gap between these standards reflects ongoing scientific debate about how much risk is acceptable. The EPA's limit was set decades ago using older toxicology data, while EWG's guideline incorporates more recent research on how carcinogens affect vulnerable populations like children and pregnant women.

Florida dominates the geographic pattern, with 10 of the 28 affected systems. North Carolina follows with 8 systems, while Ohio, Arizona, and Oklahoma have smaller clusters. This distribution reflects historical agricultural use—Florida's citrus groves and North Carolina's tobacco fields were heavy lindane users. Groundwater in these regions moves slowly, allowing old pesticides to persist longer than in areas with faster water flow. Agricultural communities and rural areas near former pesticide application sites face the highest risk, though lindane's persistence means contamination can appear far from original sources.

Removing lindane requires specialized filtration because the chemical doesn't dissolve easily in water and resists standard treatment. Activated carbon filters are highly effective, removing up to 95% of lindane when properly installed and maintained. Reverse osmosis systems achieve even better results, typically removing 99% or more. If your water system is one of the 28 affected, request your local water quality report (called a Consumer Confidence Report) to see if lindane appears in your area. If it does, or if you live in Florida or North Carolina near agricultural regions, installing a point-of-use filter on your kitchen tap or a whole-home activated carbon system provides reliable protection. Have your filter tested annually to ensure it's working—cartridges lose effectiveness over time and need replacement.

Regulatory Standards for Lindane

Cities With the Highest Lindane Levels

States Most Affected by Lindane

Frequently Asked Questions

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