Chemical has Pittsboro water customers worried

PITTSBORO -- High levels of a chlorine byproduct in the town's water supply have some residents concerned about possible health risks.

Over the past year, residents have received several notices in the mail that levels of total trihalomethanes in the water have exceeded federal standards.

Total trihalomethanes, known as TTHMs, are formed when chlorine added for disinfection reacts with natural organic matter in the water.

The federal standard for TTHMs is 0.08 milligrams per liter. The average level in Pittsboro water for the first quarter of 2007 was 0.118.

Research connects long-term exposure to TTHMs with bladder cancer, said Philip Singer, director of the Drinking Water Research Center at the UNC School of Public Health.

Pittsboro utility director John Poteat says the town has known about the problem since 2003 and is working with engineering firm Hobbs Upchurch and Associates to reduce TTHMs.

The town initially thought flushing fire hydrants to remove sediment from the water supply would do an adequate job of lowering TTHM levels, but this method proved insufficient, Poteat said.

A report by the engineers will be presented to the town by Nov. 26.

One possible solution would be switching disinfectants from chlorine to a compound called chloramine, which is used in the southern Orange County, Hillsborough, Durham and Raleigh water supplies and does not produce TTHMs, Singer said.

Boiling water or using approved filters on home faucets are effective at removing TTHMs from drinking water, though residents don't need to worry about any immediate health risks, Singer said.

"The regulation is to try to limit lifetime exposure," he said.

Pittsboro Town Board member Gene Brooks promised citizens at a recent meeting that the town is working on the problem.

"We're not ignoring this," he said.