The Texas Commission on Environmental Quality reported Wednesday that the city of Lancaster’s drinking water exceeds the maximum contaminant level for trihalomethanes.

Trihalomethanes, a group of organic compounds formed when chlorine reacts with organic matter, reached 0.091 milligrams per liter, or 0.011 over the maximum level set by the TCEQ’s drinking water standards.

Those who drink excessive amounts of water containing TTHM may experience liver, kidney or nervous system problems. There’s also an increased risk of cancer.

City officials said most residents can still safely drink the water, but those with health concerns should talk to a doctor.

The city’s water provider, Dallas Water Utilities, has made adjustments in its water treatment process to lower levels of TTHM, city officials said. City officials are also looking into other options.