A POLAR-HIGH MOLECULAR MASS CONSTITUENT OF BLEACHED KRAFT MILL EFFLUENT IS TOXIC TO MARINE ORGANISMS

A high molecular mass constituent (HMM) of whole bleached kraft mill effluent (BKME), which represents the majority of toxicity to early life stages of marine animals and a plant, has been isolated and partially characterized. BKME was subjected to fractionation coupled with toxicity testing to determine the toxicity of each isolated fraction. The toxic mode of action was also tracked throughout the fractionation using echinoderm sperm motility as an indicator. While most fractions inhibited sperm motility, BKME and HMM did not. Yet, HMM exhibited most of the toxicity of BKME to echinoderm sperm, mollusc embryos, larval sole, and kelp gametophytes. HMM was soluble only in water and appeared to be free of the resin and fatty acids or chlorinated aromatic compounds that are implicated in freshwater acute toxicity of BKME to salmonid fish. Structural analyses indicate that this polar, high molecular mass constituent was devoid of aromatic structure and had other characteristics indicative of lignin breakdown products.