After massive underground plumes of an industrial solvent were discovered in the nation's water supplies, the Environmental Protection Agency mounted a major effort in the 1990s to assess how dangerous the chemical was to human health.
Following four years of study, senior EPA scientists came to an alarming conclusion: The solvent, trichloroethylene, or TCE, was as much as 40 times more likely to cause cancer than the EPA had previously believed.
The preliminary report in 2001 laid the groundwork for tough new standards to limit public exposure to TCE. Instead of triggering any action, however, the assessment set off a high-stakes battle between the EPA and Defense Department, which had more than 1,000 military properties nationwide polluted with TCE.
By 2003, after a prolonged challenge orchestrated by the Pentagon, the EPA lost control of the issue and its TCE assessment was cast aside. As a result, any conclusion about whether millions of Americans were being contaminated by TCE was delayed indefinitely.
What happened with TCE is a stark illustration of a power shift that has badly damaged the EPA's ability to carry out one of its essential missions: assessing the health risks of toxic chemicals........
http://www.latimes.com/news/science/environment/la-na-toxic29mar29,0,5610036.story?coll=la-home-headlines