"Why the United States Leaves Deadly Chemicals on the Market"

"A six-month investigation finds that the revolving door between government and private industry has led the EPA to rely on potentially skewed research."

"Scientists are trained to express themselves rationally. They avoid personal attacks when they disagree. But some scientific arguments become so polarized that tempers fray. There may even be shouting.

Such is the current state of affairs between two camps of scientists: health effects researchers and regulatory toxicologists. Both groups study the effects of chemical exposures in humans. Both groups have publicly used terms like 'irrelevant,' 'arbitrary,' 'unfounded' and 'contrary to all accumulated physiological understanding' to describe the other’s work. Privately, the language becomes even harsher, with phrases such as 'a pseudoscience,' 'a religion' and 'rigged.'

The rift centers around the best way to measure the health effects of chemical exposures. The regulatory toxicologists typically rely on computer simulations called 'physiologically based pharmacokinetic' (PBPK) modeling. The health effects researchers—endocrinologists, developmental biologists and epidemiologists, among others— draw their conclusions from direct observations of how chemicals actually affect living things."

Valerie Brown and Elizabeth Grossman report for In These Times November 2, 2015.