In Baltimore, Maryland, leaky sewage infrastructure delivers tens of thousands of human doses of pharmaceuticals to the Chesapeake Bay every year.
In Baltimore, Maryland, leaky sewage infrastructure delivers tens of thousands of human doses of pharmaceuticals to the Chesapeake Bay every year. So reports a new study in Environmental Science & Technology that monitored an urban stream network over a yearlong period. Drug concentrations detected were persistent, variable, and occurred at ecologically relevant levels.
Pharmaceutical pollution to freshwaters is a global problem that is poorly quantified. Mixtures of drugs in lakes, rivers, and streams can disrupt animal biology and behavior, algal growth, and other ecological processes – with harmful cascading effects.
Lead author Megan Fork, a postdoctoral research associate at Cary Institute of Ecosystem Studies, says, “Pharmaceuticals enter freshwaters through multiple pathways, including effluent from wastewater treatment and septic systems, as well as agricultural runoff. An important, but often overlooked contributor is aging and faulty wastewater infrastructure, which is common in many older cities.”
For a year, weekly water samples were collected from six sites in Baltimore’s Gwynns Falls watershed. Fork explains, “Because Gwynns Falls streams don’t receive wastewater effluent, we were able to estimate annual loads of pharmaceutical pollution attributed to leaky pipes alone.” Sites represented a gradient of development, ranging from suburban to highly urban. The team also sampled a forested reference site to the northwest of the Gwynns Falls watershed.
Read more at Cary Institute of Ecosystem Studies
Image: Water sampling in a Gwynns Falls stream. (Credit: Credit: Benjamin Glass-Siegel/Baltimore Ecosystem Study)
