There’s Something in the Water

A recent study from the University of York, UK, found traces of 29 different drug compounds within two local rivers (1). The drugs – detected using HPLC-MS/MS – included antidepressants, antibiotics, painkillers, and treatments for diabetes and epilepsy. The levels were in themselves low, but the team are concerned about the long-term impact of the emissions. How can the potential consequences for human (and environmental) health be better understood? And what can be done to help? We spoke to Alistair Boxall, Professor in Environmental Science at the University of York, about his quest to find out more.

Many studies have been done on pharmaceuticals emitted into the environment, but this one looked at emissions over time and in different locations. Why?

We know that pharmaceutical active ingredients occur in the environment, but we have a less developed understanding of how concentrations vary in space and time – something we need  to properly assess the risks of these molecules to aquatic organisms. Concentrations of some active ingredients in rivers can be explained based on knowledge of what doctors in an area are prescribing at the time, and of river flows. We have had some surprises; in an earlier study, we detected some compounds that aren’t prescribed in the UK, and during periods of heavy rainfall we see elevated concentrations of compounds not usually detected, possibly due to inputs from combined sewer overflows which bypass wastewater treatment.

What sources are these drug traces likely to be coming from?

In York, we think the main source is from patient use, with a small amount arising from inappropriate disposal of medicines. In monitoring in Nigeria, for example, manufacturing inputs appear to be a major contributor.

What can be done to help prevent these emissions?

Some of the measures pharma companies can take include introducing better treatments in their factories, or, if obtaining actives from a supplier, ensuring they only obtain materials from companies with good environmental standards. Longer term, they could move towards developing more environmentally benign medicines to replace the most environmentally risky molecules. Technological developments such as personalized medicine and nanomedicine, which will reduce patient doses, will also help reduce the environmental impact of medicine.

What next steps would you like to see to tackle drug traces in the environment?

In Europe and North America, I suspect that only a small proportion of the 1,500 or so active ingredients we use are causing environmental harm. We need to develop ways in which we can identify these molecules so that mitigation efforts can focus on the compounds that really matter. This will require better sharing of data by industry and academia, and the development of approaches for prioritizing active ingredients in terms of their environmental risk. This is something we are already working on in the Innovative Medicines Initiative’s Intelligence-led Assessment of Pharmaceuticals in the Environment (iPiE) project, which involves 13 pharmaceutical companies and ten research and regulatory organizations.

Elsewhere, such as areas of Asia and Africa, the problem of pharmaceutical pollution will be more acute due to things like disease pressures, a lack of connectivity to the wastewater network, and poorer regulation. We need to understand the implications for human health and the environment, and then industry, governments, academics and the NGO community need to work together to solve the problem.