@article{EckertDiCesareKettneretal.2017, author = {Eckert, Ester M. and Di Cesare, Andrea and Kettner, Marie Therese and Arias-Andres, Maria and Fontaneto, Diego and Grossart, Hans-Peter and Corno, Gianluca}, title = {Microplastics increase impact of treated wastewater on freshwater microbial community}, series = {Environmental pollution}, volume = {234}, journal = {Environmental pollution}, publisher = {Elsevier}, address = {Oxford}, issn = {0269-7491}, doi = {10.1016/j.envpol.2017.11.070}, pages = {495 -- 502}, year = {2017}, abstract = {Plastic pollution is a major global concern with several million microplastic particles entering every day freshwater ecosystems via wastewater discharge. Microplastic particles stimulate biofilm formation (plastisphere) throughout the water column and have the potential to affect microbial community structure if they accumulate in pelagic waters, especially enhancing the proliferation of biohazardous bacteria. To test this scenario, we simulated the inflow of treated wastewater into a temperate lake using a continuous culture system with a gradient of concentration of microplastic particles. We followed the effect of microplastics on the microbial community structure and on the occurrence of integrase 1 (intl), a marker associated with mobile genetic elements known as a proxy for anthropogenic effects on the spread of antimicrobial resistance genes. The abundance of intl increased in the plastisphere with increasing microplastic particle concentration, but not in the water surrounding the microplastic particles. Likewise, the microbial community on microplastic was more similar to the original wastewater community with increasing microplastic concentrations. Our results show that microplastic particles indeed promote persistence of typical indicators of microbial anthropogenic pollution in natural waters, and substantiate that their removal from treated wastewater should be prioritised. (C) 2017 Elsevier Ltd. All rights reserved.}, language = {en} } @article{AriasAndresKettnerMikietal.2018, author = {Arias Andr{\´e}s, Mar{\´i}a de Jes{\´u}s and Kettner, Marie Therese and Miki, Takeshi and Grossart, Hans-Peter}, title = {Microplastics: New substrates for heterotrophic activity contribute to altering organic matter cycles in aquatic ecosystems}, series = {The science of the total environment : an international journal for scientific research into the environment and its relationship with man}, volume = {635}, journal = {The science of the total environment : an international journal for scientific research into the environment and its relationship with man}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0048-9697}, doi = {10.1016/j.scitotenv.2018.04.199}, pages = {1152 -- 1159}, year = {2018}, abstract = {Heterotrophic microbes with the capability to process considerable amounts of organic matter can colonize microplastic particles (MP) in aquatic ecosystems. Weather colonization of microorganisms on MP will alter ecological niche and functioning of microbial communities remains still unanswered. Therefore, we compared the functional diversity of biofilms on microplastics when incubated in three lakes in northeastern Germany differing in trophy and limnological features. For all lakes, we compared heterotrophic activities of MP biofilms with those of microorganisms in the surrounding water by using Biolog (R) EcoPlates and assessed their oxygen consumption in microcosm assays with and without MP. The present study found that the total biofilm biomass was higher in the oligo-mesotrophic and dystrophic lakes than in the eutrophic lake. In all lakes, functional diversity profiles of MP biofilms consistently differed from those in the surrounding water. However, solely in the oligo-mesotrophic lake MP biofilms had a higher functional richness compared to the ambient water. These results demonstrate that the functionality and hence the ecological role of MP-associated microbial communities are context-dependent, i.e. different environments lead to substantial changes in biomass build up and heterotrophic activities of MP biofilms. We propose that MP surfaces act as new niches for aquatic microorganisms and that the constantly increasing MP pollution has the potential to globally impact carbon dynamics of pelagic environments by altering heterotrophic activities. (C) 2018 Elsevier B.V. All rights reserved.}, language = {en} }