ABSTRACT
Eulachon were taken from the Kitimat River downstream of the discharge of a nonbleaching kraft mill, and reference fish from the Kemano River were exposed in tanks to concentrations of mill effluent. Eulachon grease was rendered from exposed and unexposed fish by a traditional method. Gas chromatographic/mass spectrometric analyses were performed on homogenates of whole fish and on eulachon grease to measure the levels of chloroanisoles (PCAs) as well as coplanar and mono-ortho-PCBs, dioxins (PCDDs), furans (PCDFs), polyaromatic hydrocarbons (PAHs) and some sulfur aromatics. The concentrations of PCBs, PCDDs, PCDFs and PAHs (excluding dibenzothiophene and its methyl derivatives) were at low background levels without statistically significant differences between exposed and unexposed fish samples. The levels of the sulfur aromatic dibenzothiophene and its mono- and dimethyl derivatives (DBT+C1DBT+C2DBT) were 181 ng g−1 fw in exposed and 18 ng g−1 fw in unexposed fish grease samples. These substances are persistent and lipophilic components of crude oil. They also occur in oil-based defoamers used in pulp mills and, consequently, in pulp mill biosludge. Their significance as pollutants in exposed eulachons needs to be evaluated. 3,5-Dichloroanisole and 2,4,5-trichloroanisole were detectable (4–70 ng g−1 lw) in all tainted and nondetectable (<2 ng g−1) in all nontainted oil samples. Levels of these PCAs in tainted eulachon grease were similar to levels of PCAs and PCVs (polychloroveratroles) in bad-tasting fish from a watercourse receiving pulp mill wastes. The source of the PCAs in the eulachons is unknown but cannot derive from bleaching.
