Chlordane
Chlordane·Affects brain, liver, kidneys
A persistent organochlorine insecticide used heavily on US homes and crops from 1948 until its ban in 1988. Still detected in soil and groundwater decades later.
Chlordane
EPA limit
0.002 mg/L (MCL)
Most at risk
Residents of homes treated for termites pre-1988, rural well-water households
Found in
City water · Well water
AquaOx filters
YesActivated coconut shell carbon
What it does to you
Health effects
Chlordane is classified by the EPA as a probable human carcinogen. The IARC classifies it as possibly carcinogenic. Long-term exposure is linked to liver cancer in animal studies and to elevated rates of non-Hodgkin lymphoma and prostate cancer in epidemiological studies of exposed workers and residents.
The compound bioaccumulates in fatty tissue and the brain. Chronic exposure damages the central nervous system, causing tremors, headaches, and cognitive deficits. It also damages the liver and kidneys, and disrupts the immune system.
Children are particularly vulnerable because chlordane crosses the placenta and is excreted in breast milk. Exposure during development is linked to lower birth weight and impaired immune function.
Where it comes from
How it gets into your water
Chlordane was used from 1948 to 1988, first on corn and citrus, then almost exclusively as a termite treatment around home foundations. The EPA banned all uses in 1988 because of cancer risk and environmental persistence.
The compound binds tightly to soil and degrades extremely slowly, with a half-life measured in decades. Homes treated for termites before 1988 often still have measurable chlordane in foundation soil, which can leach into shallow wells and indoor air. Agricultural fields treated decades ago can also still contribute to runoff.
Public water systems that draw from rivers downstream of former application areas occasionally detect chlordane, particularly after heavy rains disturb sediment.
Termite-treated foundations
Pre-1988 applications still in soil
Legacy crop applications
Banned but persistent in soil
Shallow groundwater
Migrates from contaminated soil
Find out for yourself
Is it in your water?
Public utilities test for chlordane and report results in their annual Consumer Confidence Report. Detections in city water are uncommon but persist in regions with heavy historical use.
If your home was built before 1988 and treated for termites, or if your well is near a foundation treated in that era, you should test for chlordane and the related cyclodiene insecticides (heptachlor, aldrin, dieldrin). These tend to occur together because they were applied for similar purposes.
The fix
How AquaOx filters it
Chlordane is filtered efficiently by activated carbon. The coconut shell carbon stage in The AquaOx adsorbs chlordane molecules as water passes through, with independent testing showing reductions above 95%.
For well-water households near former application sites, we recommend pairing The AquaOx with our FE Edition or RE Edition if iron or hydrogen sulfide is also present, and adding the under-sink RO for additional drinking-water polish.