Just how well was rotenone studied before EPA reached its conclusion that it does not cause cancer?
A. Rotenone was fed daily to rats, mice and dogs in studies that ranged from six months to two years. In two studies, high levels were fed daily through three generations with no evidence of significant adverse effects. No tumor induction was observed, even when 75 ppm was fed daily to rats or when 1,200 ppm was fed to mice. In the tests with both males and females of each species, there was no firm evidence that rotenone caused any increase in the incidence of tumors. In some lots, treated animals had significantly fewer tumors than untreated groups.