Three more rural water districts -- one in Arkansas and two in Texas -- have been found to have high levels of a cancer-causing chemical in their drinking water, likely because of old plastic pipes.

Sixteen districts in Kansas and Missouri already had reported high levels of vinyl chloride, a chemical known to cause cancer in humans. The Arkansas and Texas districts are the first in which high levels of the carcinogen have been found in those states.

Representatives for the plastic pipe industry and the vinyl industry said they thought the problem was centered in the nation's rural midsection, especially in Kansas and Missouri, where the contamination was revealed last year.

"We're looking in the most likely place," said Bill Carroll, who represents the vinyl industry and was in Kansas City on Friday.

But the Environmental Protection Agency is not satisfied.

Robert Morby, who heads the EPA's public drinking water office in Kansas City, Kan., said his agency was urging other regional offices, state regulators and water districts to check for vinyl chloride if they have pipe manufactured before 1977.

"We think there's a need to look in some other places," Morby said.

The vinyl chloride problem appears to develop during warm weather in systems made before 1977 that have long lengths of pipe, such as dead-end sections, in which water can sit for extended periods, experts say.

Carroll said that information is comforting, because it shows that those conditions must be present for vinyl chloride contamination to occur.

"We've seen nothing other than that type of situation," Carroll said.

About 500 rural water systems in eight states have been tested for vinyl chloride, industry representatives told the EPA on Friday. Sixty-nine systems showed some level of vinyl chloride in their water, but only 19 were above the federal limit of 2 parts per billion.

Kansas, with 11, has the most systems with high levels. The state tested 125 of its 250 rural water systems last year.

In some cases, state regulators or water district officials have taken steps to reduce vinyl chloride levels.

The Kansas City Star reported in February 1998 that state and federal agencies that regulate public drinking water had known for at least six years that parts of a rural water system in Doniphan County, Kan., were contaminated with vinyl chloride.

The agencies did not act to reduce customers' exposure until the newspaper inquired about the contamination.

Water districts are not required to sample for the contaminant after water enters the distribution system. As a result, the high levels of vinyl chloride have not been considered violations of federal drinking water regulations.

In Doniphan County, Morby said, more than 40 customers remain on bottled water as the district tries to find money to pay for new pipe. The industry has offered to give the water district free replacement pipe.

Morby and Carroll said they could not explain why Kansas seems to have so many more water districts with vinyl chloride than other states.

Carroll added that the vinyl industry would concentrate its efforts and money this year on helping states find ways to reduce vinyl chloride levels in water districts with the problem. One solution might be fairly simple: Increase the water flow through the distribution system.

Morby said he would ask EPA headquarters to make more money available for further testing this summer of rural water systems.

Pub Date: 3/22/99