Water — 'The smell is gone'

SUMMERVILLE -- The water in Legend Oaks doesn't stink like sulfur or leave spots anymore. Dorchester County Water Authority customers now drink a blend of well water and lake water that most of the rest of the Lowcountry drinks.

"The smell is gone. The taste is better. There have been no complaints that I'm aware of," said Janette Chipas of the homeowners association.

But not everybody is happy with how the new water is disinfected.

The water authority now treats water with chloramine instead of chlorine, joining Santee Cooper, Charleston Water System and Mount Pleasant Waterworks, among others. Chloramine is created when a trace of ammonia is added to chlorine to kill bacteria in surface-water supplies. It's been widely used to disinfect water for more than a decade. It's in the water used by at least one in every five people in the United States, according to the Environmental Protection Agency.

Citizen groups have formed in at least five states to stop the use of chloramine, said Susan Pickford, co-director of the Pennsylvania-based Chloramine Information Center. They are concerned that while the disinfectant does the job, it creates chemical by-products that are not federally regulated and can cause cell damage and cancer.

Both chloramine and chlorine are disinfectants. Chloramine is generally considered weaker, but it lasts longer and reduces that chlorine taste. Utilities began moving to chloramine after concerns were raised about the level of cancer-causing by-products found in chlorine. Chloramine doesn't form those by-products. But it does form other by-products, in far smaller doses.

The EPA considers it safe, more or less, in the small amounts used for water treatment. The chemical is toxic enough to fish that it has to be removed from aquarium water.

Some research has linked by-products produced by chloramine and chlorine to cancer in animals and suggests a small risk to humans.

"Although the studies with chlorine are marginal in quality, they do give an indication that adverse effects from monochloramine are not likely to occur," the EPA concluded. Public water agencies are participating in ongoing chloramine research with the EPA and S.C. Department of Health and Environmental Control.

In the Lowcountry, Charleston Water System water tends to carry about half the level of chloramine that the EPA sets as a safe limit. Santee Cooper water tends to carry about three-fourths that amount.

"Every disinfectant that you put in the water has some desirable and undesirable effects," said Andy Fairey, chief operating officer at Charleston Water System. Chloramine is safer than chlorine for the by-products that the EPA does regulate, he said. The by-products it does create show up in levels of parts per trillion rather than parts per billion -- 1,000 times lower.

"Does it affect health at that level? There's still a lot to be learned. But it is being studied," Fairey said.

The EPA safe limit was calculated studying the effect of only chloramine in the water, not the cumulative effect of its use with other chemicals, said Olga Naidenko, senior scientist with the Environmental Working Group, a Washington based nonprofit advocate for public health and the environment. "There is a concern that needs to be addressed. In reality it's the mixture and that's what we need to look at."

Marc Edwards, a Virginia Polytechnic Institute researcher who studies the corrosion effect of chemicals in treated water, said the risk of using chloramine has to be weighed against the danger of not using it or a similar disinfectant. It can corrode lead and copper, he said, but that can take years to show up, and utilities as a rule add a phosphate corrosion inhibitor.

"In isolated cases there have been some serious health issues," he said. "There's no easy answer. It makes some things better and some things worse, and hopefully we're better off for using it. But nobody can say that for sure," he said. "I have concerns, but it is certainly one of the tools utilities have to meet current EPA regulations, often at the lowest cost. And it's not an option not to meet the regulations."

Reach Bo Petersen at 843-937-5744 or bpetersen@postandcourier.com.