Objectives: The aim of this study is to assess the toxicity of prometryne in early life stages of marbled crayfish (Procambarus fallax f. virginalis) on the basis of mortality, early ontogeny, growth rate, and histopathology during and at the end of the test.
Design: The early life stages of marbled crayfish were exposed to prometryne at four concentrations, 0.51, (reported concentration in Czech rivers), 144, 1440, and 4320 μg x l(-1) for 53 days and compared to crayfish in a non-treated control group. RESU LTS: Prometryne in concentration 144, 1444 and 4320 μg x l(-1) caused decrease of weight and specific growth rates of crayfish. Crayfish exposed the highest concentration 4320 μg x l(-1) showed delay in ontogeny development. All crayfish groups exposed to prometryne showed histopathological changes in gill. On the basis of histopathological changes the values of LOEC = 0.51 μg x l(-1) and NOEC = for 0.10 μg x l(-1) of prometryne for marbled crayfish juveniles was estimated.
Conclusions: Chronic exposure of prometryne on early life stages of crayfish has affected their mortality, growth rate, and histology. Some of the changes were observed only at higher exposures (144, 1444 and 4320 μg x l(-1)), but histopathological changes in gills were observed also in crayfish exposed to the real environmental concentration in Czech rivers (i.e. 0.51 μg x l(-1)), which is about 9 times lower than maximal concentration (4.40 μg x l(-1)) reported in surface waters of Greece. Concentrations of prometryne in World rivers have been reported to generally vary in the range of 0.1-4.40 μg x l(-1).