Engineered Nanoparticles in the Environment: A Plea for Effect Assessment at the Community and Ecosystem Level
Thursday, November 10, 2011
Joint Seminar with Biology
Mark O. Gessner, Ph.D.
Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB)
Department of Ecology, Berlin Institute of Technology, Germany
Abstract: Engineered nanoparticles are pervading our lives. Their very properties that are so useful for industrial applications potentially pose severe risks to both human health and the environment. This is particularly true for silver nanoparticles, which exert strong antimicrobial properties. This notwithstanding, there is a huge mismatch between the rates of nanoparticle design, production and proliferation, and the rate of knowledge generation about their fate and effects. Furthermore, studies addressing environmental effects are typically limited to classical ecotoxicological tests targeting individual organisms or indicators (endpoints) at the subcellular level. In the presentation, I will argue that effect assessments are urgently needed at the community and ecosystem level of biological organization. Key in this context is the recognition of indirect effects in biological communities resulting from species interactions such as predation, competition and facilitation. Application of these concepts in a risk-assessment context can build on a long tradition in community ecology. An additional central consideration is that organisms can profoundly influence their environment. This suggests that approaches targeting biologically mediated ecosystem processes are critically needed to assess impacts of nanoparticles at the ecosystem level. I will present these concepts and will attempt to illustrate them based on very scant data from a recently started project on silver nanoparticle effects on stream communities and processes, and from previous work carried out by colleagues.