Qualifying ecotoxicity research on tropical hardwood leachates
G M F Van Eetvelde, P Marchal, M Stevens
Almost as a rule, quantification and identification of various types of environmental contamination is grounded on chemical evaluation principles. Yet for monitoring surface water pollution, aquatic bio-assays may provide a more direct way to assess the potential hazard of environmental samples. A battery of such tests is experienced onto leachates of tropical hardwoods used in ground and water contact. Four of seven wood species tested exhibited no acute toxic profile, whilst afzelia, afrormosia and mainly merbau revealed a considerable toxicity response for all organisms tested. These results, although at screening level, demonstrate the natural toxicity of particular tropical hardwood extractives towards the aquatic compartment. Hence, a welcome source of information is obtained, so as to weigh the ecotoxicity results previously gathered on preservative treated wood.