Hexachlorocyclopentadiene

City of Opelousas Water System

Hexachlorocyclopentadiene was historically used for the manufacture of currently banned pesticides, such as endrin, dieldrin and chlordane. It’s still used for production of flame retardants, resins and plastics.

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
2013	N/A	0	N/A
2014	ND	4	ND
2015	ND	10	ND
2016	N/A	0	N/A
2017	ND	2	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 2 ppb

The EWG Health Guideline of 2 ppb for hexachlorocyclopentadiene 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 the stomach and intestines.

EPA Maximum Contaminant
Level (MCL) 50 ppb

The legal limit for hexachlorocyclopentadiene, established in 1992, was based on a toxicity study in laboratory animals conducted in the 1980s.

ppb = parts per billion

All test results

Date	Lab ID	Result
2014-09-08	AD96570	ND
2014-09-08	AD96570	ND
2014-10-06	AD98315	ND
2014-10-06	AD98315	ND
2015-03-09	35178831003	ND
2015-03-09	35178831001	ND
2015-03-09	35178831002	ND
2015-03-09	35178831003	ND
2015-03-09	35178831005	ND
2015-03-09	35178831004	ND
2015-03-09	35178831002	ND
2015-03-09	35178831001	ND
2015-03-09	35178831004	ND
2015-03-09	35178831005	ND
2017-09-18	35336897005	ND
2017-09-18	35336897005	ND
2018-01-09	35367792001	ND
2018-01-09	35367792005	ND
2018-01-09	35367792004	ND
2018-01-09	35367792003	ND
2018-01-09	35367792002	ND
2018-01-09	35367792001	ND
2018-01-09	35367792005	ND
2018-01-09	35367792004	ND
2018-01-09	35367792003	ND
2018-01-09	35367792002	ND