Predicting Pore Water EPA-34 PAH Concentrations and Toxicity in Pyrogenic-Impacted Sediments Using Pyrene Content

• Published in: Environmental science & technology 2011-06, Vol.45 (12), p.5139-5146
• Main Authors: Arp, Hans Peter H, Azzolina, Nicholas A, Cornelissen, Gerard, Hawthorne, Steven B
• Format: Article
• Language: English
• Subjects: Amphipoda - drug effects; Animal, plant and microbial ecology; Animals; Applied ecology; Biological and medical sciences; Characterization of Natural and Affected Environments; Contaminated sediments; Ecotoxicology, biological effects of pollution; Environmental Monitoring - legislation & jurisprudence; Fundamental and applied biological sciences. Psychology; Geologic Sediments - chemistry; Government Regulation; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; Polycyclic Aromatic Hydrocarbons - toxicity; Porosity - drug effects; Pyrenes - analysis; Risk assessment; Sediments; Statistical analysis; Temperature; Toxicity; United States; United States Environmental Protection Agency; Water - chemistry; Water Pollutants, Chemical
• ISSN: 0013-936X; 1520-5851; 1520-5851
• DOI: 10.1021/es2007935

Sediment and freely dissolved pore water concentrations of the U.S. Environmental Protection Agency’s list of 34 alkyl and parent PAHs (EPA-34) were measured in 335 sediment samples from 19 different sites impacted by manufactured gas plants, aluminum smelters and other pyrogenic sources. The total EPA-34 freely dissolved pore water concentration, Cpw,EPA-34, expressed as toxic units (TU) is currently considered one of the most accurate measures to assess risk at such sites; however, it is very seldom measured. With this data set, we address how accurately Cpw,EPA-34 can be estimated using limited 16 parent PAH data (EPA-16) commonly available for such sites. An exhaustive statistical analysis of the obtained data validated earlier observations that PAHs with more than 3 rings are present in similar relative abundances and their partitioning behavior typically follows Raoult’s law and models developed for coal tar. As a result, sediment and freely dissolved pore water concentrations of pyrene and other 3- and 4-ring PAHs exhibit good log–log correlations (r2 > 0.8) to most individual EPA-34 PAHs and also to Cpw,EPA-34. Correlations improve further by including the ratio of high to low molecular weight PAHs, as 2-ring PAHs exhibit the most variability in terms of their relative abundance. The most practical result of the current work is that log Cpw,EPA-34 estimated by the recommended pyrene-based estimation techniques was similarly well correlated to % survival of the benthic amphipods Hyalella azteca and Leptocheirus plumulosus as directly measured log Cpw,EPA-34 values (n = 211). Incorporation of the presented Cpw,EPA-34 estimation techniques could substantially improve risk assessments and guidelines for sediments impacted by pyrogenic residues, especially when limited data are available, without requiring any extra data or measurement costs.