Phyto-toxicological effects of chromated copper arsenate preservative and wood extractives from selected Malaysian timber species

The wastewater and contaminated soil from wood extractives and both the wood–preservation and wood processing industries are considered significant pollutants because of their chemical components such as tannins, lignins, chlorinated compounds and wood preservation. This study evaluated the phyto-toxicity effects of wood extractives from four selected Malaysian timbers species and CCA (Chromated Copper Arsenate) on lettuce seed germination. The wood extractives were obtained using hot and cold water extractives. The concentration of both wood extractives for each species and CCA solution were diluted into three different concentrations. The seed germination method was employed to test the phytotoxicity of the wood extractives and CCA solution. The experimental result of this study indicates that concentration > 0.75 % w/w CCA caused < 50% of the lettuce seed death and the mean of germination was 41.3 %. At concentration < 0.25 % w/w CCA, no observed effect concentration (NOEC) on lettuce seed germination was observed and the germinating rate was recorded as 96.3 to 88.8 %. The phyto-toxic effects of wood extractives for each species suggested that no observed effect concentration (NOEC) on the mean of seed germination