SAN ANGELO, Texas — The Texas Commission on Environmental Quality (TCEQ) on Thursday notified the city of San Angelo that its drinking water has elevated levels of potentially carcinogenic chemicals known as trihalomethanes (THMs).
THMs are a group of four chemicals that are formed along with other disinfection byproducts when chlorine or other disinfectants used to control microbial contaminants in drinking water react with naturally occurring organic and inorganic matter in water.
The U.S. Environmental Protection Agency’s Maximum Contaminant Level (MCL) for THMs is 80 parts per billion (ppb). According to the public notice, San Angelo’s water has 96 ppb.
TCEQ said that residents don''t need to seek a new water supply and that the contaminant is only harmful if ingested over long periods of time.
"Some people who drink water containing trihalomethanes in excess of the (maximum contaminant level) over many years may experience problems with their liver, kidney, or central nervous systems, and may have an increased risk of getting cancer," the public notice stated.
The city will make improvements to its water treatment plant chemical feed, mixing and chlorination system to address the problem, according to the story.