By Sara Jerome
Wastewater researchers have an unusual new tool at their disposal: bathtubs pumped full of speed.
Scientists are pouring amphetamines into fiberglass bathtubs — albeit, shallow, narrow tubs meant to serve as artificial streams — to recreate the effect of pharmaceuticals and personal care products (PPCPs) on the environment, a crucial issue for the wastewater industry.
Researchers, policy officials, and environmentalists say drugs are escaping wastewater treatment processes and contaminating rivers and streams. “Most treatment plants lack the often-expensive technologies necessary to filter out amphetamines and other potentially dangerous ‘chemicals of emerging concern,’” Ars Technica explained in a recent close-up on PPCP research. The practice of dumping untreated sewage also presents an opportunity for PPCPs to enter the environment.
Researchers at the Cary Institute, an environmental research group, are using tubs to examine this problem in the lab.
“While previous studies have looked at whether drugs are present in bodies of water like streams and ponds, this is one of the first that systematically examines the biological implications of their presence,” the report said.
“To quantify ecosystem change, the scientists outfitted eight of the Cary Institute’s artificial streams with rocks, stream microorganisms, bacteria, algae, and aquatic insects collected from an untainted stream in upstate New York. At the start of the experiment, they added D-amphetamine to four tubs until they had a similar concentration to [certain Baltimore] streams. The other four were not treated,” the report said.
Here’s what happened to the contaminated ecosystem simulated in the lab:
After just a week, life in the amphetamine-treated streams began changing. The aquatic insects they contained developed and reproduced like they were on speed — much more quickly. The amount of algae was down by nearly 50 percent compared to untreated streams; the algae that was present produced much less oxygen. After three weeks, DNA tests revealed that the diversity and number of bacteria and diatoms (a simple type of algae) present in the treated streams was markedly different from those in the untreated streams.
The Cary Institute hosts a video of its artificial streams. The scientists called for more research because some of the effects of amphetamines on the human body are unknown.
PPCPs are only found in tiny concentrations in waterways, but research suggests they may affect wildlife and possibly even humans. PPCPs are unregulated, but the U.S. EPA has placed various pharmaceuticals on its Contaminant Candidate List 4 (CCL4), meaning that the agency is monitoring whether regulatory action is appropriate.
To read more about PPCPs visit Water Online’s Source Water Contamination Solutions Center.
Image credit: "Erich Ferdinand," Pills (white rabbit) © 2006, used under an Attribution 2.0 Generic license: https://creativecommons.org/licenses/by/2.0/