May 22, 2001
Delegates from 127 countries formally voted approval of the Stockholm Convention on Persistent Organic Pollutants (POPS), a treaty calling for the initial elimination of 12 of the most dangerous man-made chemicals, nine of which are pesticides. POPS are often toxic at very low levels, resist degradation and thus persist for decades or longer, because they become concentrated in living tissue, are readily spread by atmospheric and ocean currents.
