@hun-ren.hu
HUN-REN Hungarian Research Network, CERS
Environmental Science, Environmental Engineering, Waste Management and Disposal
Scopus Publications
V. Varjú and Ágnes Óvári
Informa UK Limited
Ágnes Óvári, András Donát Kovács, and Jenő Zsolt Farkas
Elsevier BV
Viktor Varjú, Ágnes Óvári, Cecília Mezei, Andrea Suvák, and Csaba Vér
Ubiquity Press, Ltd.
David Sanjuan-Delmás, Sue Ellen Taelman, Alessandro Arlati, Andreas Obersteg, Csaba Vér, Ágnes Óvári, Davide Tonini, and Jo Dewulf
Elsevier BV
Rolf Altenburger, Werner Brack, William R. Greco, Matthias Grote, Klaus Jung, Agnes Ovari, Janet Riedl, Katrin Schwab, and Eberhard Küster
American Chemical Society (ACS)
N-phenyl-2-naphthylamine, a sediment contaminant previously identified as a major toxicant of site-specific importance was investigated for its mode of toxic action. From short-term bioassays with daphnids, fish eggs, bacteria, and algae it appears that this compound has specific phytotoxic properties at concentrations below 100 microg/L, which cannot be explained assuming an unspecific narcosis type of action in plants. Also, hydroxy-, nitro-, and methylderivatives show clear excess toxicity as compared to baseline toxic effects. Of several plant-specific growth and development processes investigated, only photosynthesis could be demonstrated to be affected at short exposure times and low concentrations. Disturbance of primary photosynthetic reactions such as oxygen evolution and fluorescence quenching, however, becomes only apparent after 2-3 h of exposure, which is in sharp contrast to known specific inhibitors targeting processes such as electron transport or ATP production. This, and concentration-time-effect modeling lead to the suggestion that N-phenyl-2-naphthylamine acts intracellular as a reactive compound in cell membranes producing irreversible, and thus cumulative, damage over time in algae. The effects may become first apparent in membrane-rich compartments such as the algal chloroplast.