How safe is rotenone to people?
A. In 1973, a Spanish investigator claimed that rotenone fed to six rats resulted in mammary tumors in three of the animals. Many investigators have since tested rotenone on large numbers of animals; some using the very same approach as the Spanish study. None has observed any tumor-inducing effects. EPA has ruled that the Spanish study was not valid and that the allegations are not supported by sound scientific evidence.