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Expanding Research in Environmental Drug Residues


Published Nov 21, 2011

New funding will strengthen research at the MistraPharma Centre at KTH into more efficient wastewater treatment processes. Among the Centre’s focus areas is risk assessment studies, aiming to see whether trace amounts of common pharmaceuticals may be causing environmental bacteria to become antibiotic resistant.

Environmental risks from pharmaceutical residues in waterways are poorly understood.

Eight research groups belonging to the MistraPharma Centre can continue working to understand the impacts of drug residues in wastewater, thanks to a grant of SEK 52 million ($7.6 million) from  the Swedish Foundation for Strategic Environmental Research (Mistra).

Environmental authorities and pharmaceutical manufacturers alike are concerned about the unknown effects of biologically active substances that pass through water treatment facilities from the human body into the environment.

“Our biggest concern is emissions of antibiotics, which can result in antibiotic resistance”, says Dr Christina Rudén, physician, toxicologist and director of the MistraPharma Centre.

“Antibiotics kill all types of bacteria indiscriminately. When antibiotic-resistant human bacteria enter the environment through our toilets, they may cause other bacteria to develop resistance. This could be an enormous problem,” Rudén says.

With the rise in international trade and tourism in recent decades, researchers see a growing risk of antibiotic resistance worldwide.

Earlier studies show that synthetic hormones similar to progesterone pass unaltered through Swedish municipal sewage treatment plants, possibly affecting the reproductive cycles of fish and amphibians. Other research findings show that widely prescribed anti-inflammatory agents such as diclofenac (marketed around the world under dozens of brand names), can be harmful to the kidneys of birds and fish.

“The MistraPharma research program is now entering its second phase, which is aimed at improving available methods for identification of drugs that can have negative environmental effects”, says Rudén.

“We’re also looking closely at new technologies for water treatment. KTH Bioprocess Technology will evaluate two methods for removing drug traces that could become additional steps in the water purification process.”

Scientists at MistraPharma will bring the new technology to Swedish sewage treatment plants for large-scale testing aimed at moving toward widespread implementation.

Christina Ruden, Director the MistraPharma Centre at KTH.

“It’s important that the new treatment techniques are effective in removing the most harmful molecules, but at the same time they have to be proved economically and practically feasible for the treatment plants”, explains Rudén.

She notes that the environmental risks of pharmaceuticals are poorly understood. “The first step is to identify which substances are hazardous, and we’ve assembled a list of topics that MistraPharma will look at”, she says.

But she also makes clear that risks to human health are judged to be extremely low. Medicines are thoroughly tested for safety before being approved for prescriptions.

“Concentrations of pharmaceuticals in drinking water are very low, and we don’t see this as a health risk. But it’s different for fish that live in and ‘breathe’ water through the gills”, she says.

The issues are to be addressed in Environmental Objectives Advisory Council co-ordinated by the Swedish Environmental Protection Agency. On that board, Rudén leads a team of experts on pharmaceuticals working to supply scientific data to the government’s Strategy for a Non-Toxic Environment.

“We’re discussing how to reduce the emission of pharmaceuticals from wastewater treatment plants, and how European legislation in the field could be strengthened”, she says.

In addition to KTH, MistraPharma is supported by Sweden’s Sahlgrenska Academy at the University of Gothenburg, Umeå University, Uppsala University, Stockholm University, Chalmers University of Technology and Brunel University in London.

For more information: Christina Ruden, +46-8-790 95 87;

Read more about MistraPharma


Katrina Ahlfort