Acute Toxic Effects Caused by Leachate from Five Different Tree Species on Artemia Salina and Vibro Fischeri

In this study, leachates resulting from leaching tests carried out with sawdust from five tree species were investigated. The studied species were: Pedunculate oak (Quercus robur), Scots pine (Pinus sylvestris), European larch (Larix decidua), Norway spruce (Picea abies) and European beech (Fagus sylvatica). The analyses included chemical parameters such as pH, TOC and phenolic compounds (reported as total poly-phenols) and acute toxicity on two different organisms, the crustacean Artemia salina and the bacteria Vibro fischeri (Microtox^®). There are very high amounts of different phenolic compounds in the leachate, and large differences between tree species. The leachates produced by sawdust and bark of different tree species presented great variation regarding acute toxicity. V. fischeri was more sensitive than A. salina and leachates from pine sawdust and pine bark produced the highest toxicity response from V. fischeri. This study indicates that bark is one component of the tree anatomy that needs to be handled as a potential hazardous material to the aquatic environment. The large variation in toxicity presented by different tree species need to be taken into account when assessing the impacts to surrounding watercourses and constructing wastewater treatment facilities for the wood-based industry such as irrigation water, stormwater runoff from storage areas.