evaluation of polycyclic aromatic hydrocarbon (PAH) runoff from highways into estuarine wetlands of South Carolina

• Published in: Archives of environmental contamination and toxicology 2005-10, Vol.49 (3), p.362-370
• Main Authors: Van Dolah, R.F, Riekerk, G.H.M, Levisen, M.V, Scott, G.I, Fulton, M.H, Bearden, D, Sivertsen, S, Chung, K.W, Sanger, D.M
• Format: Article
• Language: English
• Subjects: Ampelisca verrilli; Amphipoda - drug effects; Animal, plant and microbial ecology; Animals; Applied ecology; Aquatic habitats; Aquatic plants; Bioassays; Biological and medical sciences; Bivalvia - drug effects; Brackish; Combustion products; Contaminants; Ecotoxicology, biological effects of pollution; Environmental Monitoring; estuaries; Fundamental and applied biological sciences. Psychology; General aspects; Geologic Sediments - chemistry; Habitats; Highways; Marine; Mercenaria mercenaria; Motor Vehicles; Mud flats; Polychaeta - drug effects; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; Polycyclic Aromatic Hydrocarbons - radiation effects; Polycyclic Aromatic Hydrocarbons - toxicity; Roads; Roads & highways; Runoff; Seawater; sediment contamination; Sediments; South Carolina; Streblospio benedicti; Survival Analysis; Toxicity; toxicity testing; Ultraviolet Rays - adverse effects; Vehicle Emissions; Water Movements; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - radiation effects; Water Pollutants, Chemical - toxicity; water pollution; Wetlands
• ISSN: 0090-4341; 1432-0703
• DOI: 10.1007/s00244-004-0210-1

This study investigated the concentrations and potential toxicity of polycyclic aromatic hydrocarbons (PAHs) associated with highway runoff into adjacent estuarine wetlands from road segments representing three levels of average daily traffic (ADT): low (25,000 ADT) based on SC Department of Transportation data. Sediments from three estuarine wetland habitats (tidal creeks, Spartina marsh, and mud flats) adjacent to these road segments were sampled to represent nine highway use class/habitat type combinations. Surficial sediments were collected at 3, 25, and 50 meters from the upland/wetland interface along transects established perpendicular to the road at each site, with additional samples taken from the road berm. Average PAH concentrations, representing 25 compounds, ranged from 3.9 to 11,000 ng/g dry weight. Berm samples had significantly greater total PAH concentrations than samples taken in any of the wetland habitats. Average total PAH concentrations decreased with increasing distance from the road berm within the wetland habitats sampled, but the differences were not statistically significant. Average total PAH concentrations also were not significantly different among the wetland habitats compared. Analysis of PAH profiles indicated that the PAH source was dominated by pyrogenic combustion products rather than from petrogenic sources. This, combined with the presence of dibenzothio-phene, which is a tire oxidation product, indicated that the primary source of PAHs was related to vehicles. Two sites with total PAH concentrations exceeding published bioeffects levels were resampled for bioassay tests using the amphipod Ampelisca verrilli, the polychaete Streblospio benedicti, and the clam, Mercenaria mercenaria, with the first two assays conducted under UV lighting since previous studies had demonstrated enhanced UV toxicity of PAHs for these species. No toxicity was observed in the amphipod or polychaete assays. Toxicity was observed in the juvenile clam assay at one site, possibly due to the combined effects of PAHs and other contaminants present.