trans-1,2-Dichloroethylene

City of Nampa

1,2-Dichloroethylene, a neurotoxic solvent, exists in two different forms: trans-1,2-dichloroethylene and cis-1,2-dichloroethylene. A mixture of the two forms is used to manufacture other solvents and chemical products.

MORE ABOUT THIS CONTAMINANT

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Range of results
2014	N/A	0	N/A
2015	N/A	0	N/A
2016	ND	13	ND
2017	ND	5	ND
2018	ND	10	ND
2019	N/A	0	N/A

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 60 ppb

The EWG Health Guideline of 60 ppb for trans-1,2-dichloroethylene was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against harm to internal organs.

EPA Maximum Contaminant
Level (MCL) 100 ppb

The legal limit for trans-1,2-dichloroethylene, established in 1991, was based on a toxicity study in laboratory animals conducted in the 1980s.

ppb = parts per billion

All test results

Date	Lab ID	Result
2016-04-20	V1616221	ND
2016-07-20	V1632285	ND
2016-10-07	V1646180	ND
2016-11-17	V1652977	ND
2016-11-17	V1652982	ND
2016-11-17	V1652993	ND
2016-11-17	V1652971	ND
2016-11-17	V1652973	ND
2016-11-17	V1652975	ND
2016-11-17	V1652985	ND
2016-11-17	V1652987	ND
2016-11-17	V1652991	ND
2016-11-17	V1652995	ND
2017-01-31	V1703805	ND
2017-01-31	V1703804	ND
2017-04-11	V1714411	ND
2017-08-09	V1735777	ND
2017-10-18	V1748770	ND
2018-07-02	V1830569	ND
2018-10-08	V1850109	ND
2018-10-08	V1850028	ND
2018-10-08	V1850027	ND
2018-10-08	V1850025	ND
2018-10-08	V1850023	ND
2018-10-08	V1850019	ND
2018-10-08	V1850015	ND
2018-10-08	V1850014	ND
2018-10-08	V1850013	ND