Pharmaceuticals in the Environment


Elimination of pharmaceutical active substances from municipal sewage plants and aquatic systems.

Issue

Using pharmaceuticals is a fundamental component in modern medicine today. Currently there are approximately 8,500 preparations with about 2,900 different active agents available on the pharmaceutical market. Just in human medicine 30,000 t of active agents are put into circulation each year, according to recent studies. Active agents of applied and naturally egested as well as of improperly disposed pharmaceuticals (disposal of drugs via toilet/sink) end up in  municipal sewage plants via the municipal sewer  system. The elimination of these mainly persistent substances within sewage plants is rather inefficient. Therefore these substances partly enter aquatic ecosystems (lakes, rivers, ground water) with the treated wastewater from the sewage plant effluent. In this way those substances, which are often environmentally relevant, reach drinking water via drinking water abstraction and hence they end up in the food chain. Still there is deficient knowledge about long term consequences for humans, aquatic communities and ecosystems of these feeds, despite of increased efforts of research in this field since the 70’s.

Entry paths of pharmaceutical active agents into aquatic systems

(Pharmaceutical) Industry, humans and agriculture are to be referred to as the three originators of pharmaceutical charges into environment. But one has to differentiate that those originators contribute in considerably different amounts. Figure 1 shows schematically possible entry paths into surface waters respectively directly into ground water.

 

pharma charge flow

 

At current state of knowledge, the discharge of pharmaceutical substances into environment from municipal sewage plant effluents is quantitatively most significant. The  sewage plant inflows are mainly fed from municipal and clinical wastewater (occasionally also pre-treated industrial wastewater). By intended use of remedies, they, respectively their metabolites, enter municipal wastewater via urine/stool and hence the feed of sewage plants. This entry path also applies to the discharge of unused pharmaceutical products via the toilet.

In agricultural livestock farming the main entry of pharmaceuticals occurs via the soil (deploying semi-liquid manure as a fertilizer on the fields). From there, pharmaceuticals reach hydrous ground layers or groundwater horizons due to their chemical structure. The speed of this process is depending on the substance’s mobility.

Objective

Due to its special structure in staff the institute of Medical Biotechnology is able to bundle competences from environmental engineering, medicine and chemistry. Therefore innovative solutions for the elimination of pharmaceutical substances from aquatic systems will be achieved. The working group „Medical Environmental Engineering“ (supervised by Dr. Georgiadis) has its main focus on municipal wastewaters (sewage plants).  It is intended to develop modular cleaning techniques for pharmaceutical substances in municipal wastewaters, using high quality, sensitive (trace-) analytics (HPLC/MS-MS). Those cleaning techniques are to be characterized by a high selectivity to certain groups of pharmaceutical substances, economic feasibility, reliability and robustness.

Literature

  • Stan, H.-J.; Heberer, T.; Linkerhägner, M.: Vorkommen von Clofibrinsäure im aquatischen System - Führt die therapeutische Anwendung zu einer Belastung von Oberflächen-, Grund- und Trinkwasser? Vom Wasser 83, S. 57-68, 1994
  • Ternes, Th.: Vorkommen von Pharmaka in Gewässern , Wasser & Boden, 53/4, 2001.
  • Umweltbundesamt: UBA Forschungsvorhaben Mengenermittlung und Systematisierung von Arzneimittelwirkstoffen im Rahmen der Umweltprüfung von Human- und Tierarzneimitteln gemäß §28 AMG, FKZ 299 67 401/1, Berlin, UBA F&E-Bericht 20067401, 2003
  • Götz, K., Keil, F.: Medikamentenversorgung in privaten Haushalten: Ein Faktor bei der Gewässerbelastung mit Arzneimittelwirkstoffen?, UWSF-Z Umweltchem. Ökotox. 18(3) 180-188, 2007.
  • Bergmann, A.; Fohrmann, R.; Hembrock-Heger, A.: Bewertung der Umweltrelevanz von Arzneistoffen, Umweltwiss Schadst Forsch (2008) 20: 197-208, DOI 10.1007/s12302-008-0005-5, Springer Verlag, 2008.
  • Kümmerer, K.: Pharmaceuticals in the Environment, 3rd Edition, Springer-Verlag Berlin Heidelberg, 2010, ISBN: 978-3-642-09412-5.