According to environmental experts, drug residues in drinking water are a growing problem.Over 150 active ingredients have been repeatedly detected in the environment in research projects and special measurement programs – mostly in lakes, streams and rivers. According to the Federal Environment Agency, antihypertensive agents, beta blockers , anti-epileptic drugs, pain relievers such as diclofenac and ibuprofen, antibiotics and, above all, X-ray contrast media can be found in the environment and, accordingly, in our drinking water. Researchers suspect that in view of the aging society and the associated increase in drug consumption, water pollution will continue to increase.
Medicines enter the water cycle in many ways
How do the drugs get into the drinking water? Let us consider this question using the example of diclofenac : Around 85 tons of pain relievers are used in Germany every year. However, 70 percent of the active ingredient leaves the body naturally – and ends up in the wastewater. About 60 tons of diclofenac enter the water cycle via the urine.
If a person drinks an average of two liters of water a day throughout their life, they will use over 50,000 liters of water in 80 years. It is difficult to calculate how much drug residues he will take up.
Very little is known about possible reactions; all residues of the around 3,000 drugs approved in Europe come together. However, it is known from the animal world that sex changes have been observed in fish that live at sewage treatment plant exits after ingestion of estrogen (ethinylestradiol from the birth control pill ).
Medicines in the water: Incorrect disposal and animal husbandry
In the opinion of the Federal Environment Agency, however, it is also a problem that ignorant or overly comfortable consumers simply dispose of medicines that have not been taken or that have expired in the toilet or sink. From there they end up in the ground and surface water. Conventional sewage treatment plants and water treatment technology can usually only filter the residues poorly.
And another problem arises thanks to the intensive animal husbandry: Due to the manure treatment of the meadows and fields, there is an additional burden of medication from veterinary medicine – antibiotics, hormones, etc. In fish farming, antibiotics and wormers are discharged directly into surface waters.
There is a need for research
It is true that the proven agents in drinking water are many times lower than the prescribed daily dose. But that doesn’t mean they are safe. A scientifically based assessment of the risk does not yet exist. Above all, the effect that could result if consumers ingested several active ingredients simultaneously in low concentrations through drinking water for many years is still unclear.
But there is a great need for research here. Because two very worrying trends are associated with drug residues in water: The increasing incidence of fertility disorders and multi-resistant microorganisms.