"A largely ignored contaminant doesn’t just resemble bisphenol A, the chemical found to leach out of hard plastic water bottles. It’s BPA’s fluorinated twin — on steroids.

New laboratory studies in Japan indicate that the twin, called bisphenol AF, or BPAF, may be even more potent than BPA in altering the effects of steroid hormones such as estrogens in the body.

The unusual way that BPAF blocks some estrogen actions and fosters others “could make this a vicious compound, a very toxic compound,” says Jan-Åke Gustafsson, a molecular endocrinologist at the University of Houston. The chemical is an ingredient of many plastics, electronic devices, optical fibers and more."

Janet Raloff reports for Science News May 12, 2010. [2]