Retention and toxicity of a coal liquid in artificially contaminated sediments

Columbia River fine sediments were artificially spiked with coal liquids and removal rates and composition of retained phenolics were characterized following sequential water extractions. Acute (48 h) exposure of invertebrates Daphnia magna and Chironomus tentans within test containers provided an index of toxicity. Total phenols in the water column declined rapidly, with resultant reduced toxicity to pelagic D. magna. Significant mortalities to C. tentans larvae residing in the sediments were noted at the lowest sediment exposure level of 0.28 mg 1−1 total phenolics. Relative rates of phenolic compound removal from the sediments were noted as: C1, C2, C3, C4 phenols > C1, C2 indanols > phenol > C3 indanols. Sediment retention of less soluble, higher molecular weight phenolics may affect behavior and survival of sediment dwelling organisms following observance of transient effects in the water column.