What is Lindane and Why Does It Matter?

Lindane is a synthetic pesticide that was once widely used to kill insects on crops, in soil, and even on human skin to treat lice and scabies. It belongs to a chemical family called organochlorines — the same group as DDT. The U.S. banned most agricultural uses of lindane in 2006, and the FDA banned lindane-based lice shampoos in 2015. Despite those bans, lindane persists in the environment for decades. It enters drinking water through runoff from contaminated soil, leaching from old agricultural land, and in some cases from legacy industrial sites. Because it doesn't break down quickly, water systems in farming-heavy regions can still detect it long after the chemical was last applied.

Lindane is a known neurotoxin and probable human carcinogen, according to the EPA and the International Agency for Research on Cancer (IARC). Even at low exposure levels, it can disrupt the nervous system and interfere with hormone function. Short-term exposure at higher concentrations has been linked to seizures, liver damage, and kidney stress. Long-term, low-level exposure — the kind more likely through drinking water — raises concern for liver toxicity and increased cancer risk, particularly non-Hodgkin's lymphoma (according to IARC). Children and pregnant women face the greatest risk, since developing bodies are more sensitive to neurotoxic and hormone-disrupting chemicals.

The EPA sets the maximum contaminant level (MCL) for lindane in drinking water at 0.2 parts per billion (ppb). The Environmental Working Group (EWG) recommends a much stricter health guideline of 0.0004 ppb — 500 times lower than the federal limit. That gap matters. Across the 22 water systems where lindane has been detected, the average level measured 0.01 ppb. One system exceeded the EWG health guideline, reaching a maximum of 0.117 ppb. While that peak falls below the EPA's legal limit of 0.2 ppb, it sits nearly 300 times above the EWG's health-protective threshold. Regulatory compliance doesn't always mean your water is as safe as it could be.

Florida leads the country with 9 water systems detecting lindane — more than any other state. North Carolina and Ohio each recorded detections in 3 systems, followed by Arizona with 2 and South Carolina with 1. Florida's numbers aren't surprising. The state has a long history of intensive agriculture, and its sandy, porous soil allows chemicals to move quickly into groundwater. North and South Carolina share similar agricultural legacies, particularly with tobacco and cotton farming, both of which historically relied on organochlorine pesticides. Ohio's detections likely reflect its industrial farming past in the western part of the state. Arizona's presence on this list is less typical but may relate to older irrigation practices and contaminated groundwater sources in rural areas.

The good news is that lindane is very effectively removed by the right filtration technology. Activated carbon filters — especially granular activated carbon (GAC) — can significantly reduce lindane levels in drinking water. For the most complete protection, a reverse osmosis (RO) system removes up to 99% of organochlorine compounds like lindane. Echo Water's reverse osmosis systems are designed specifically to address contaminants like these, including pesticides that fall through the cracks of federal regulation. If you live in Florida, the Carolinas, Ohio, or Arizona, it's worth checking your local water quality report — called a Consumer Confidence Report — to see if lindane has been detected in your system. If it has, don't wait for regulations to catch up. A quality home filter gives you control over what ends up in your glass, regardless of what the legal limit allows.

Regulatory Standards for Lindane

Cities With the Highest Lindane Levels

States Most Affected by Lindane

Frequently Asked Questions

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