And so do area waterways. Specifically, trace amounts of amphetamine - from both prescription drug residues and methamphetamine - is altering the ecosystems in the streams, according to people who've been researching the Gwynns Falls system for the past 18 years. The residual chemicals associated with amphetamine cause algae in the biofilm layer on the streambed to produce less oxygen, for one thing. It also changes the composition of bacterial colonies and accelerates the development of certain insect species. Which isn't to say its entirely bad; it's just different, although the reduction in oxygen production doesn't seem especially helpful.
While drugs have long been detected in urban waterways, the researchers have shown for the first time that the chemicals can cause chain reactions up the food chain long after their effects wear off for users.
For now, Baltimore needs to get cracking on fixing their leaky sewer pipes.