Are drugs harmful for the environment?

Medicines released into the environment may be a risk to living species in the long term. Jeanne Garric’s ecotoxicology team at Cemagref Lyon has shown that certain molecules disrupt reproduction, embryo development and growth of representative organisms in aquatic environments. Toxicity tests have been conducted in the laboratory on Daphnia, Rotifera and zebra fish under standard protocols. Active pharmaceuticals ingredients (APIs) concentrations in the environment however are found to be 1000 to 100,000 times too low to cause acute toxicity.

Cemagref scientists have tested a dozen of the most widely used APIs in France and Europe, covering a wide spectrum of molecular diversity. The research was carried out as part of the European Rempharmawater research programme and French Enimed programme under the PNETOX national ecotoxicology programme funded by the environment ministry.

In France and Europe as a whole, most drugs swallowed end up in rivers after passing through a wastewater treatment station. Any drug not entirely broken down will reach surface waters. For this reason degradability and biodegradability in STP and receiving ecosystem is one of the important key parameters to understand for the risk assessment of such APIs.. But even in small amounts, a drug, may have toxic effects. Very low concentrations of the some b-blockers, in surface waters may affect invertebrate reproduction.

Answering questions as to the environmental impact of medicines has become vitally important, in terms of sustainable development. Mutual interactions between different drugs and their effects on sediments also needs investigating. This is a major challenge, because a continuous stream of such molecules are pouring into the environment.