1,1-Dichloroethene
1,1-DCE·Affects liver, kidneys
An industrial chemical and breakdown product of trichloroethane in groundwater. Used to make food wrap and other plastics; regulated by the EPA at 7 ppb.
1,1-DCE
EPA limit
0.007 mg/L (MCL)
Most at risk
Households near plastic manufacturing, old industrial sites, or known TCE/TCA plumes
Found in
City water · Well water · Industrial areas
AquaOx filters
YesActivated coconut shell carbon
What it does to you
Health effects
1,1-DCE primarily affects the liver and the kidneys. Chronic animal studies show liver enlargement, fatty changes, and kidney damage. The EPA classifies the compound as a possible human carcinogen, though the human evidence is limited.
Like other chlorinated VOCs, 1,1-DCE is volatile, so it off-gasses from water during hot showers and contributes to inhalation exposure in addition to drinking water ingestion.
The MCL of 7 ppb sits well below the lowest adverse effect level seen in animal studies, with a safety factor applied for chronic exposure.
Where it comes from
How it gets into your water
1,1-DCE has two main routes into drinking water. First, direct industrial discharge: it is used to manufacture polyvinylidene chloride, the polymer behind food wrap and other plastics. Releases from chemical plants and improper waste handling have contaminated groundwater near manufacturing sites.
Second, and more commonly, 1,1-DCE appears as a microbial breakdown product of 1,1,1-trichloroethane in anaerobic groundwater. If 1,1-DCE shows up in your well, there is likely a parent solvent plume upstream from an old industrial facility, leaking storage tank, or hazardous waste site.
Plastic manufacturing
Polyvinylidene chloride production
Industrial sites
Breakdown of 1,1,1-TCA in groundwater
Contaminated wells
Plumes from former solvent disposal
Underground tanks
Leaks from solvent storage
Find out for yourself
Is it in your water?
1,1-DCE is EPA-regulated, so all community water systems test for it and report results in their Consumer Confidence Report. Detections in treated city water are uncommon.
Private well owners in industrial corridors or near former waste sites should request a VOC panel that includes 1,1-DCE along with TCE, PCE, and the TCA family. State drinking-water programs maintain maps of known plume sites that can help you decide whether to test.
The fix
How AquaOx filters it
Activated carbon adsorption is the proven treatment for chlorinated VOCs. The Centaur catalytic carbon and coconut shell carbon stages in The AquaOx filter 1,1-DCE as water passes through.
For homes on a known industrial plume, we recommend pairing The AquaOx whole-home system with the under-sink RO at the kitchen tap so drinking and cooking water get a second-stage polish.