Contaminant Guide

Trichloroethylene (TCE) in Well Water

Trichloroethylene (TCE) in private well water: where it comes from, what the limits are, how to test for it, and which treatment methods actually remove it.

Where trichloroethylene (tce) comes from

  • legacy industrial degreaser used in metal manufacturing, electronics, and aerospace
  • dry cleaning solvent (historical use before perchloroethylene dominance)
  • groundwater plume migration from contaminated industrial or military sites
  • leaking underground storage tanks and improperly disposed solvent waste
  • Superfund and NPL sites — TCE is the most commonly detected VOC at NPL sites

Health considerations

  • kidney cancer and non-Hodgkin lymphoma — IARC Group 1 carcinogen (sufficient evidence in humans). EPA classified TCE as carcinogenic to humans in 2011. Cohort studies of occupationally exposed workers and community studies near contaminated sites show elevated kidney cancer and NHL risk.
  • liver and central nervous system toxicity — Acute high-dose exposure causes dizziness, headaches, and unconsciousness. Chronic low-dose exposure linked to liver damage and neurotoxicity in animal studies.
  • reproductive and developmental toxicity — EPA classified TCE as a potential reproductive toxicant and developmental hazard. Associated with cardiac birth defects (Camp Lejeune cohort studies).

MCL = 5 μg/L; MCLG = 0 (carcinogen — no safe level). The gap between MCLG and MCL reflects treatment feasibility limits. TCE was historically regulated under the Safe Drinking Water Act as a volatile organic compound. EPA’s 2011 cancer reclassification strengthened the case for MCLG = 0.

Who is most at risk

  • residents near active or former military installations (TCE widely used in maintenance)
  • residents near Superfund NPL sites
  • dry cleaner workers and nearby residents
  • pregnant women (developmental hazard)
  • private well owners in industrial corridors of Midwest and Mid-Atlantic states

Testing

EPA Method 524.3 or 502.2 (purge-and-trap GC/MS); volatile organic compound (VOC) panel at certified lab; collect in 40 mL VOA vials with HCl preservative, no headspace; avoid contact with plastic containers

Find a certified lab and learn how to collect a sample

Treatment

  • granular activated carbon (GAC) — effective for VOC removal, NSF/ANSI 58
  • packed tower aeration (air stripping) — most effective for high concentrations
  • reverse osmosis with GAC pre-filter
  • activated carbon block point-of-use filter (NSF/ANSI 53)

Compare trichloroethylene (tce) treatment systems

Regulatory framework

MCL: 5 µg/L · MCLG: 0 µg/L

MCL = 5 μg/L; MCLG = 0 (carcinogen — no safe level). The gap between MCLG and MCL reflects treatment feasibility limits. TCE was historically regulated under the Safe Drinking Water Act as a volatile organic compound. EPA’s 2011 cancer reclassification strengthened the case for MCLG = 0.

Detection

EPA Method 524.3 or 502.2 (purge-and-trap GC/MS); volatile organic compound (VOC) panel at certified lab; collect in 40 mL VOA vials with HCl preservative, no headspace; avoid contact with plastic containers

Occurrence

Most commonly reported in: Michigan, Ohio, Pennsylvania, New York, California, Massachusetts, Virginia, Texas.

  • any near industrial or military sites
  • fractured bedrock (dense non-aqueous phase liquid migration)
  • alluvial near former industrial corridors

Data access

Access our data API and methodology

References

  1. Scott, C.S., & Jinot, J. (2011). Trichloroethylene and cancer: systematic and quantitative review of epidemiologic evidence for identifying hazards. International Journal of Environmental Research and Public Health, 8(11), 4238-4272. https://doi.org/10.3390/ijerph8114238
  2. Chiu, W.A., Jinot, J., Scott, C.S., et al. (2013). Human health effects of trichloroethylene: key findings and scientific issues. Environmental Health Perspectives, 121(3), 303-311. https://doi.org/10.1289/ehp.1205879