Abstract

 Multiple lines of evidence (LOE) were compared at several sites in the United States in sediment quality assessments. The LOE primarily included: laboratory toxicity, physicochemistry, sediment quality guidelines, biosurveys, in situ toxicity (caged organisms), and tissue residues. Effects were measured in the surface water (low and high flow), surficial sediment, and pore water/groundwater. The various LOE were compared to each other to determine their similarity and how well they predicted other LOE. Findings showed that, in general, the LOE were 40 to 70% predictive of each other. No one LOE was a reliable surrogate for other LOE, as expected. Each LOE provided unique information, associated with differing exposure/fate and effects scenarios, methodological artifacts, and/or theoretical assumptions. The field-based LOE (biosurveys, in situ toxicity and bioaccumulation) provided the most reliable indicators of impairment, as they were subject to fewer methodological artifacts, theoretical assumptions, and better characterized exposure. At sites with low to moderately high contamination, differences should be expected between LOE. Understanding the linkage of these data requires more extensive characterizations of stressors and spatial-temporal exposure patterns.