Do PAHs Pose Unacceptable Ecological Risks to Terrestrial Receptors at Hazardous Waste Sites?

Abstract

ABSTRACT Polycyclic aromatic hydrocarbons (PAHs) are identified as Constituents of Potential Concern (CoPC) at many hazardous waste sites because of disposal, spills, leaking storage tanks, and incineration. The Superfund Public Information System (SPIS) RODs and CERCLIS Information database covering the period fiscal years 1996–1998 were queried for information on PAHs in soils. Forty-five sites were identified that had PAHs in soil. Predominantly, the sites were munitions facilities or military bases. Of the 45 sites, only two concluded that adverse ecological effects were occurring from PAHs. At both sites, the conclusions were based on Hazard Quotients (HQs) exceeding 1.0. For 29 sites, PAHs were characterized “as not posing an adverse effect” to plants or invertebrates. PAHs appeared not to pose an adverse effect at five other sites, but the information was equivocal. At another five sites, there “was too little information to evaluate possible PAH effects,” though PAHs did not figure in the remediation options. Empirical evidence indicates that wildlife exposures via food are mostly from foliar deposition, which tends to be low away from urban areas. To date, there is no evidence that PAHs in soils at hazardous waste sites result in adverse effects to plants, invertebrates, or wildlife.