[ Back to EurekAlert! ] Public release date: 1-Apr-2013
[ | E-mail Share Share ]

Contact: Lori Quillen
quillenl@caryinstitute.org
845-677-7600 x121
Cary Institute of Ecosystem Studies

Streams stressed by pharmaceutical pollution

Antihistamines alter sensitive and essential habitat

IMAGE: Wappinger Creek in New York's Hudson Valley was one of the streams investigated in the study.

Click here for more information.

Millbrook, NY Pharmaceuticals commonly found in the environment are disrupting streams, with unknown impacts on aquatic life and water quality. So reports a new Ecological Applications paper, which highlights the ecological cost of pharmaceutical waste and the need for more research into environmental impacts.

Lead author Dr. Emma Rosi-Marshall, a scientist at the Cary Institute of Ecosystem Studies, comments: "Pharmaceutical pollution is now detected in waters throughout the world. Causes include aging infrastructure, sewage overflows, and agricultural runoff. Even when waste water makes it to sewage treatment facilities, they aren't equipped to remove pharmaceuticals. As a result, our streams and rivers are exposed to a cocktail of synthetic compounds, from stimulants and antibiotics to analgesics and antihistamines."

With colleagues from Indiana University and Loyola University Chicago, Rosi-Marshall looked at how six common pharmaceuticals influenced similar-sized streams in New York, Maryland, and Indiana. Caffeine, the antibiotic ciprofloxacin, the antidiabetic metformin, two antihistimines used to treat heartburn (cimetidine and ranitidine), and one antihistamine used to treat allergies (diphenhydramine) were investigated, both alone and in combinations, using pharmaceutical-diffusing substrates.

IMAGE: This is a close-up of Wappinger Creek.

Click here for more information.

Rosi-Marshall explains, "We focused on the response of biofilms which most people know as the slippery coating on stream rocks because they're vital to stream health. They might not look like much to the naked eye, but biofilms are complex communities composed of algae, fungi, and bacteria all living and working together. In streams, biofilms contribute to water quality by recycling nutrients and organic matter. They're also a major food source for invertebrates that, in turn, feed larger animals like fish."

Healthy streams are slippery streams. And it turns out that antihistamines dry more than our noses. The most striking result of the study was diphenhydramine's effects on algal production and microbial respiration. Exposure caused biofilms to experience up to a 99% decrease in photosynthesis, as well as significant drops in respiration. Diphenhydramine also caused a change in the bacterial species present in the biofilms, including an increase in a bacterial group known to degrade toxic compounds and a reduction in a group that digests compounds produced by plants and algae.

IMAGE: This is an excerpt of a poster on stream biofilm communities created by Andrew Dopheide and Gillian Lewis, University of Auckland.

Click here for more information.

Results suggest that this antihistamine is disrupting the ecology of these sensitive biofilm communities. Rosi-Marshall notes, "We know that diphenhydramine is commonly found in the environment. And its effect on biofilms could have repercussions for animals in stream food webs, like insects and fish. We need additional studies looking at the concentrations that cause ecosystem disruption, and how they react with other stressors, such as excess nutrients."

The other pharmaceuticals investigated also had a measurable effect on biofilm respiration, both alone and in combinations. More work is needed to understand how drug mixtures, which most natural streams experience, impact freshwater systems.

Society's dependence on pharmaceuticals is not likely to wane. Nor is its need for clean, fresh water. This study adds another piece of evidence to the case calling for innovations in the way we manage waste water. Currently, only a fraction of the world's waste water is treated, and the infrastructure in many developed nations is aging.

###

Contributors: EMMA J. ROSI-MARSHALL (Cary Institute of Ecosystem Studies), DUSTIN KINCAID (Cary Institute of Ecosystem Studies), HEATHER BECHTOLD (Cary Institute of Ecosystem Studies), TODD V. ROYER (School of Public and Environmental Affairs, Indiana University), MIGUEL ROJAS (Department of Biology, Loyola University Chicago), and JOHN J. KELLY (Department of Biology, Loyola University Chicago).



[ Back to EurekAlert! ] [ | E-mail Share Share ]

 


AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.