title: Effects of nano-TiO(2) in combination with ambient UV-irradiation on a leaf shredding amphipod.
abstract: Production and use of engineered nanoparticles, such as titanium dioxide nanoparticles (nTiO(2)), is increasing worldwide, enhancing their probability to enter aquatic environments. However, direct effects of nTiO(2) as well as ecotoxicological consequences due to the interactions of nTiO(2) with environmental factors like ultraviolet (UV) irradiation on representatives of detrital food webs have not been assessed so far. Hence, the present study displayed for the first time adverse sublethal effects of nTiO(2) at concentrations as low as 0.2 mg L(-1) on the leaf shredding amphipod Gammarus fossarum both in presence and absence of ambient UV-irradiation following a 7-d exposure. In absence of UV-irradiation, however, the effects seemed to be driven by accumulation of nTiO(2) at the bottom of the test vessels to which the gammarids were potentially exposed. The adverse sublethal and lethal effects on gammarids caused by the combined application of nTiO(2) and ambient UV-irradiation are suggested to be driven by the formation of reactive oxygen species. In conclusion, both the accumulation of nTiO(2) at the bottom of the test vessel and the UV induced formation of reactive oxygen species clearly affected its ecotoxicity, which is recommended for consideration in the environmental risk assessment of nanoparticles.
authors.affiliation: Institute for Environmental Sciences, University of Koblenz-Landau, Fortstrasse 7, D-76829 Landau/Palatinate, Germany. bundschuh@uni-landau.de
authors.forename: Mirco
authors.initials: M
authors.lastname: Bundschuh
authors.forename: Jochen P
authors.initials: JP
authors.lastname: Zubrod
authors.forename: Dominic
authors.initials: D
authors.lastname: Englert
authors.forename: Frank
authors.initials: F
authors.lastname: Seitz
authors.forename: Ricki R
authors.initials: RR
authors.lastname: Rosenfeldt
authors.forename: Ralf
authors.initials: R
authors.lastname: Schulz
mesh_terms: D033304:Amphipoda / Q000187:drug effects*; D000818:Animals; D020387:Food Chain; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D018515:Plant Leaves; D017382:Reactive Oxygen Species / Q000633:toxicity; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D017382:Reactive Oxygen Species; C009495:titanium dioxide; D014025:Titanium