The Pentagon stalled efforts to clean water supplies contaminated by a carcinogenic chemical despite evidence that it posed a significant health risk to millions of people, it was reported yesterday.

The Environmental Protection Agency (EPA) investigated the solvent, trichloroethylene, extensively used on military bases, after significant quantities were found in water supplies. In its report, published in 2001, the EPA found it to be 40 times more likely to cause cancer than had been previously thought, and recommended tough safety standards to limit public exposure. There was also evidence the chemical played a role in birth defects.

But the Los Angeles Times reported that the defence department, which owns 1,400 bases and other sites contaminated by trichloroethylene (TCE), fought the findings, challenging their scientific basis. Under pressure from the Pentagon, political appointees at the EPA overruled their own scientists, took them off the case and postponed action pending a further study by the National Academy of Sciences, which is due to report this summer.

"The evidence is that there was some monkey business going on between the EPA and the Pentagon," said Gina Solomon, an expert on environmental medicine at the University of California, who was on the scientific board that reviewed the EPA report. "The 2001 report was an excellent piece of scientific work," Dr Solomon told the Guardian.

A Pentagon spokeswoman, Major Susan Idziak, said the defense department believed "a better scientific understanding of the toxicity of TCE [was needed] so that cleanup levels are accurately set at levels protective to public health and the environment."

© Guardian Newspapers Limited 2006

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