Trumpalaikiai kelių priežiūros druskos tirpalų ūminio toksiškumo vaivorykštiniam upėtakiui (Oncorhynchus mykiss) tyrimai

Abstract

The impact of chlorides and other traffic pollutants which fall into snow was comprehensively studied in countries using salts for road maintenance. The salt concentrations were evaluated in snow cover, soil, underground waters, plants and trees. In order to show the impact of road maintenance salts (RMS) on fish different studies were performed under laboratory conditions. Short-term toxicity test were conducted on rainbow trout Oncorhynchus mykiss using a set of biological parameters. Comparative studies of the lethal toxicity of RMS and CS did not reveal clear significant differences in the 96–hour LC50 of these chemicals. The 96-hour LC50 of the RMS was 18,25 g/l, and CS – 20,38 g/l, respectively. Probably, these differen-ces in LC50 were caused by all elements constituted RMS. Further-more, some specific differences in toxic effects of these salts were observed within the exposure period. Mortality during the first 24 h of exposure was only registered for fish exposed to the highest CS concentrations – 20,0 g/l and 22,0 g/l. Lethal effect due to RMS du-ring the 24 h occurred already at lower concentrations (16 g/l) and at all subsequent higher concentrations of this salt.