The objective of this preliminary study was to compare the relative acute toxicity and water chemistry of leachate from different species of wood waste typically landfilled or used as cover in landscaping or equestrian facilities in the Lower Mainland of British Columbia. Comparisons of the relative toxicity of wood waste (mostly bark and sapwood) leachate from six different tree species, red cedar, yellow cedar, sitka spruce, Douglas fir, western hemlock, and black cottonwood, were made for Microtox, 96-hr LC50 rainbow trout and 48-hr LC50 daphnia magna bioassays. The leachate from different species were generated concurrently in a laboratory by statically soaking the wood waste in a leachant of de-ionized water for 28 days. Dissolved oxygen, pH, conductance, chemical oxygen demand, acidity pH 8.3 and Microtox were monitored throughout the course of the experiment. A number of other water chemistry parameters were also monitored at the end of the 28 day experiment. The results in this report were based upon a limited number of samples and further research would be needed to substantiate the findings.
Moore, Karen. 1992. Wood Waste Leachate Characterization Study. B. C. Environment