Research News
Retention reservoir of a water supply works. Photo: André Künzelmann / UFZ
Further Information:
Dr. Rolf Altenburger at the UFZ
UFZ Newsletter on demographic change, 02/2013 (in German)
UFZ Special "Chemicals in the Environment", 10/2012 (in German)
Medication Contaminates our Water
Owing to medical progress and improved sustenance, humans live increasingly longer lives. One aspect that tends to be neglected in this context is the effect this social change has on the quality of our water. Older people tend to consume more medication. By excretion and improper disposal, the active agents end up in waste water as well as in surface and drinking water.
A new category: environmental stable chemicals
Our body is unable to decompose many kinds of medication and sewage plants often fail to filter out these substances. Rolf Altenburger, ecotoxicologist at the Helmholtz Centre for Environmental Research – UFZ, identifies the problem: "We are in the process of producing a new category of environmentally stable chemicals." In the case of many of these active agents, the researchers as yet do not know whether these may cause damage to the environment. The painkiller diclofenac, however, has already revealed a negative impact: in Pakistan, it was released into the environment, causing large numbers of vultures to die of kidney failure. It can also cause damage to the kidneys of fish. The EU therefore now put diclofenac on the list of pollutants that are to be controlled in EU water bodies. Yet diclofenac is only one of thousands of chemicals used in large amounts.
Investigate adverse effects of drugs
Rolf Altenburger employs a combination of biological and chemical procedures: with his working group, he first examines potential damaging effects of samples from the environment by using biological reactions in fish eggs and green algae. The researchers then identify the pollutants by way of chemical analysis techniques. However, the complex chemical structures of pharmaceuticals render classical instruments of environmental analysis inapplicable. For example, in the case of certain drugs, the effects can be determined only after sustained periods of effectiveness. This includes hormones from contraceptives, which influenced the sexual maturity of fish in European water bodies and led to feminisation of fish populations. Although the scientists focus in particular on the effects on the environment and less on the effects on humans, there are methods combining both human toxicology and ecotoxicology: for instance, the researchers investigate whether the receptors a drug is designed to react to exist also in fish. By observing the fish, they can assess whether active agents in the water cause undesired or unexpected effects.
Ideas for water treatment
New technologies are required also in the field of waste water treatment. Polymer researchers from the Helmholtz-Zentrum Geesthacht Centre for Materials and Coastal Research now have developed dual switchable membranes that, depending on the size of their pores, filter out of the water different biomolecules, such as hormones, proteins and genetic material. By contrast, a project at the UFZ envisions the use of catalytically active nanoparticles absorbing the active agents in the water. The nanoparticles first are magnetised so that after the filtering process they can be fished out of the water again with the help of a magnet. Additional cleansing processes could be applied also directly where active agents enter into the water, for example, at hospitals. "Of course, the most cost-efficient method would be to find structures that are biocompatible in themselves", adds Altenburger, "but especially in the case of pharmaceuticals this is as yet not even remotely a criterion."
