When sewage leaks, Baltimore's waterways are not just fouled by the waste. They also become contaminated with chemical residues of pharmaceuticals, personal care products and even illicit drugs, researchers say.
And such substances can have effects beyond those listed on warning labels.
Traces of amphetamines from prescription drugs and methamphetamine make algae produce less oxygen, speed the growth of midge flies and change the mix of bacteria on stream bottoms, according to scientists who have been gathering data from the Gwynns Falls for nearly two decades.
While drugs have long been detected in urban waterways, the researchers have shown for the first time that the...