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Total trihalomethanes (TTHMs) more about

this contaminant

Trihalomethanes are cancer-causing contaminants that form during water treatment with chlorine and other disinfectants. The total trihalomethanes group includes four chemicals: chloroform, bromodichloromethane, dibromochloromethane and bromoform.

Total trihalomethanes (TTHMs) was found at 286 times above EWG's Health Guideline.

EWG Health Guideline 0.15 ppb or less This Utility 42.9 ppb Legal Limit 80 ppb National Average 30.1 ppb State Average 36.4 ppb

The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2015-2017.

ppb = parts per billion

Health Risks The health guideline of 0.15 parts per billion, or ppb, for the group of four trihalomethanes, or THM4/TTHM, was defined in a peer-reviewed scientific study by EWG and represents a one-in-one-million lifetime cancer risk level.