Are some chemicals more dangerous at low doses?
Scientific American
April 3, 2009
By David Biello
There are some 82,000 chemicals used commercially in the U.S., but only a fraction have been tested to make sure they're safe and just five are regulated by the U.S. Environmental Protection Agency (EPA), according to congressional investigators. But a government scientist says there's no guarantee testing actually rules out health risks anyway.
The basic premise of safety testing for chemicals is that anything can kill you in high enough doses (even too much water too fast can be lethal). The goal is to find safe levels that cause no harm. But new research suggests that some chemicals may be more dangerous than previously believed at low levels when acting in concert with other chemicals.