Active ingredients from medicines can get into the environment through a variety of routes, and once there they can prove harmful to wildlife and ecosystems. In the EU, new medicines are required to undergo an environmental risk assessment (ERA). However, very few existing medicines have been checked for their environmental impact.
Here, there are two major challenges. Firstly, it is hard to assess which existing medicines might be most harmful to the environment and so should be prioritised for testing. Secondly, monitoring the levels of the active pharmaceutical ingredient (API) of a drug in the environment is a mammoth task and is extremely costly.
The Innovative Medicines Initiative (IMI) project iPiE developed a tool called ePiE, which models the path of an API from the moment the medicine is taken by a patient, via the toilet and sewage pipes to waste water treatment plants, to the moment it is released into a river. Now the IMI project PREMIER is building on the results of iPiE, including the ePiE tool.
Previous studies have shown that ePiE works well. Now, researchers have tested the ability of ePiE to predict levels of ibuprofen in four major European river basins: Ouse and Tyne (UK), Rhine (Germany), Tagus (Spain) and Sava (Slovenia and Croatia). They chose the painkiller ibuprofen because it may be included the list of priority substances in the EU’s Water Framework Directive which is designed to ensure Europe’s waters are kept clean. The river basins selected allowed the team to test the model in regions with different ibuprofen consumption rates, population densities and climates. In the study, the PREMIER team provided the improved iPiE model, while Ramboll and Reckitt provided the data on ibuprofen.
The team fed data on ibuprofen consumption in the different regions into the model and compared the results to actual concentrations of ibuprofen as measured in the different rivers. Their results, published in the journal Environmental Research, reveal that ePiE makes ‘useful, conservative’ exposure predictions. Furthermore, incorporating specific information relating to the river basin or country under study, such as custom waste water treatment plant removal rates for the drug, improves the accuracy of the predictions.
The team warns users against extrapolating consumption data between countries when modelling the environmental exposure to pharmaceuticals, as levels of per capita consumption can vary wildly from one country to another. They also note that consumption can change over time.
In conclusion, ePiE can provide a suitable alternative to fill gaps in physically monitoring levels of APIs in Europe’s many river basins.
There are other models for predicting water quality in European rivers. However, one thing that sets ePiE apart is its inclusion of the details of all the wastewater treatment plants in Europe, information which is essential for predicting concentrations of APIs in water.
Meanwhile the PREMIER team is continuing to develop ePiE, which now covers 1 500 European river basins. For example, the team is updating the information the model uses on wastewater treatment plants to reflect the growing numbers of plants that use three treatment steps (currently ePiE allows for two treatment steps). The team also wants to expand the model to include the levels of APIs in river sediment.
Looking to the future, they are exploring how to include scenarios that would give an idea of the levels of APIs in agricultural soils (e.g. for cases where effluent from waste water treatment plants is used to irrigate crops). They’re also planning a module that can predict API levels in living things such as worms, fish and birds of prey, and so describe the accumulation of APIs in simplified food webs.
iPiE and PREMIER are supported by the Innovative Medicines Initiative, a partnership between the European Union and the European pharmaceutical industry.
Find out more
Read the article in Environmental Research
Read this report on how EU-funded projects, including iPiE, are addressing micropollutants in water systems