@article{GrzesiukSpijkermanLachmannetal.2018,
  author    = {Grzesiuk, Malgorzata and Spijkerman, Elly and Lachmann, Sabrina C. and Wacker, Alexander},
  title     = {Environmental concentrations of pharmaceuticals directly affect phytoplankton and effects propagate through trophic interactions},
  series = {Ecotoxicology and Environmental Safety},
  volume    = {156},
  journal   = {Ecotoxicology and Environmental Safety},
  publisher = {Elsevier},
  address   = {San Diego},
  issn      = {0147-6513},
  doi       = {10.1016/j.ecoenv.2018.03.019},
  pages     = {271 -- 278},
  year      = {2018},
  abstract  = {Pharmaceuticals are found in freshwater ecosystems where even low concentrations in the range of ng L-1 may affect aquatic organisms. In the current study, we investigated the effects of chronic exposure to three pharmaceuticals on two microalgae, a potential modulation of the effects by additional inorganic phosphorus (Pi) limitation, and a potential propagation of the pharmaceuticals' effect across a trophic interaction. The latter considers that pharmaceuticals are bioaccumulated by algae, potentially metabolized into more (or less) toxic derivates and consequently consumed by zooplankton. We cultured Acutodesmus obliquus and Nannochloropsis limnetica in Pi-replete and Pi-limited medium contaminated with one of three commonly human used pharmaceuticals: fluoxetine, ibuprofen, and propranolol. Secondly, we tested to what extent first level consumers (Daphnia magna) were affected when fed with pharmaceutical-grown algae. Chronic exposure, covering 30 generations, led to (i) decreased cell numbers of A. obliquus in the presence of fluoxetine (under Pi-replete conditions) (ii) increased carotenoid to chlorophyll ratios in N. limnetica (under Pi-limited conditions), and (iii) increased photosynthetic yields in A. obliquus (in both Pi-conditions). In addition, ibuprofen affected both algae and their consumer: Feeding ibuprofen-contaminated algae to Pi-stressed D. magna improved their survival. We demonstrate, that even very low concentrations of pharmaceuticals present in freshwater ecosystems can significantly affect aquatic organisms when chronically exposed. Our study indicates that pharmaceutical effects can cross trophic levels and travel up the food chain.},
  language  = {en}
}
@article{GrzesiukWackerSpijkerman2016,
  author    = {Grzesiuk, Malgorzata and Wacker, Alexander and Spijkerman, Elly},
  title     = {Photosynthetic sensitivity of phytoplankton to commonly used pharmaceuticals and its dependence on cellular phosphorus status},
  series = {Ecotoxicology},
  volume    = {25},
  journal   = {Ecotoxicology},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {0963-9292},
  doi       = {10.1007/s10646-016-1628-8},
  pages     = {697 -- 707},
  year      = {2016},
  abstract  = {Recently pharmaceuticals have become significant environmental pollutants in aquatic ecosystems, that could affect primary producers such as microalgae. Here we analyzed the effect of pharmaceuticals on the photosynthesis of microalgae commonly found in freshwater-two species of Chlorophyceae and a member of the Eustigmatophyceae, via PAM fluorometry. As pharmaceuticals, three medicines often consumed in households were chosen: (i) fluoxetine, an antidepressant, (ii) propranolol, a beta-blocker and (iii) ibuprofen, an anti-inflammatory and analgesic medicine. The EC50 for the quantum yield of photosystem II in phytoplankton acclimated to inorganic phosphorus (P-i)-replete and P-i-limited conditions was estimated. Acute toxicity experiments over a 5 h exposure revealed that Nannochloropsis limnetica was the least sensitive to pharmaceuticals in its photosynthetic yield out of all species tested. Although the estimation of sub-lethal effects can be vital in contrast to that of LC(50)s, the EC50 values in all species and for all medicines were orders of magnitude higher than concentrations found in polluted surface water. Chlamydomonas reinhardtii was the most sensitive to fluoxetine (EC50 of 1.6 mg L-1), and propranolol (EC50 of 3 mg L-1). Acutodesmus obliquus was most sensitive to ibuprofen (EC50 of 288 mg L-1). Additionally, the sensitivity to the pharmaceuticals changed under a P-i-limitation; the green algae became less sensitive to fluoxetine and propranolol. In contrast, P-i-limited algal species were more sensitive to ibuprofen. Our results suggest that the sensitivity of algae to pharmaceuticals is (i) highly compound- and species-specific and (ii) dependent on the cellular P status.},
  language  = {en}
}