A study released in Environmental Science & Technology has found that pharmaceutical and illicit drugs are polluting steams in Baltimore. We talked to the study’s coauthor Emma Rosi-Marshall to find out the impact this is having on stream life.
ResearchGate: Could you explain your study and the impact that too-high amphetamine levels have on aquatic ecosystems?
Emma Rosi-Marshall: Our research team studied the concentrations of a number of pharmaceuticals in urban streams in Baltimore that have been studied as part of an NSF-funded urban long-term Ecological Research site. We detected a number of pharmaceuticals, including amphetamines, and were interested in whether these may have an effect on aquatic organisms.
At the Cary Institute’s artificial stream facility, we measured the effects of environmentally-relevant concentrations of amphetamine on stream algae, stream bacteria, and aquatic insects. We found that amphetamine suppressed the rates of algal production, changed the community composition of bacteria and diatoms, and led to the earlier emergence of aquatic insects. Algae, bacteria, and insects are at the base of aquatic food webs. They have an influence on the health of other aquatic life, including fish and animals that live along streams such as spiders, birds, and bats.
RG: Why are the levels of amphetamines in waterways increasing?
Rosi-Marshall: Although we did not study changes in pharmaceutical concentrations over time, we know that the human population is increasing and that pharmaceutical use is on the rise globally, with no sign of slowing down. More drugs are being produced and consumed, yet at the same time, our sewage infrastructure is decaying and inadequate. This is likely to lead to a continued presence of pharmaceuticals, including amphetamines, in streams and potentially increased concentrations over time. What we put in our bodies or use in our everyday lives can eventually make its way into aquatic ecosystems. It’s not just amphetamines that are on the rise, but the occurrence of a wide array of compounds that may have effects on aquatic ecosystems.
