Biota - Sediment partitioning of aluminium smelter related PAHs and pulp mill related diterpenes by intertidal clams at Kitimat, British Columbia

► Aluminium smelter coke, pitch and pyrogenic PAHs are not bioavailable to soft shell clams. ► PAHs from oil discharges, plant detritus and pulp mill effluent are all bioavailable to clams. ► Pulp mill diterpenes/PAHs are at high concentrations and ∼1000-fold more bioavailable than smelter PAHs. ► Biota compositions do not reflect sediments when only a tiny fraction of sediment PAHs accumulates. ► The release of plant terpenes by pulp mills may represent an undocumented risk to aquatic biota.