Limited bioavailability of sediment pah near an aluminum smelter: Contamination does not equal effects

Abstract

Abstract-A Sediment Quality Triad study involving synoptic measures of polycyclic aromatic hydrocarbon (PAH) contamination, toxicity, and resident community (benthic infauna, crab) alteration was conducted to assess impacts from an aluminum smelter discharge. No sediment toxicity was observed, despite extensive testing since 1988 on four test species. Evidence of effects on resident communities was minimal. Effects were not expected in areas Ͼ1 km from the smelter, because PAH concentrations have decreased with recent effluent improvements to below levels associated with effects in other studies. However, concentrations within 1 km of the smelter were high (maximum concentration was 10,000 mg/kg total PAH, although most were Ͻ150 mg/kg). Based on the literature, those concentrations should have had significant effects on toxicity test responses and benthic communities. Because they did not, we conclude that availability of sediment PAH was limited. Concentrations of parent PAH and metabolites in Dungeness crab (Cancer magister) were also low, supporting the hypothesis of limited bioavailability. Bioavailability may be limited because much of the PAH is present as pitch or coal particles. This study indicates that high contaminant concentrations may not be associated with effects, if availability is limited.

Relationship between soft bottom macrofauna and polycyclic aromatic hydrocarbons (PAH) from smelter discharge in Norwegian fjords and coastal waters

“…Details of the organisms than PAHs in a dissolved state. Similar conoccurrence and distribution patterns of PAHs in the clusions were reached by Paine et al (1996), as they fjords are given by NES et al (1995) and N z s & Oug were unable to document toxicity from heavily PAH-(1997PAH-( , 1998. The smelters are located near the heads contaminated sediments near a Canadian aluminium smelter.…”

“…Indeed, studies of PAH profile patterns in the fjords have indicated that the PAHs are resistant to degradation and transformation reactions (Nces & Oug 1997, 1998. Correspondingly, Paine et al (1996) concluded that sediment PAHs present in the form of pitch or coal tar particles in smelter-affected Canadian fjords are of limited bioavailability and do not exhibit toxic effects on the benthic fauna.…”

Predicting bioavailability of PAHs and PCBs with porewater concentrations measured by solid‐phase microextraction fibers

“…Due to their persistence and potential for bioaccumulation, these contaminants are of high concern to environmental risk assessors. Assessment of toxicity and bioaccumulation of HOCs with total extractable contaminant concentration in the sediment (bulk sediment concentration) is unreliable and often provides poor predictions [1,2]. Sediment porewater concentration of HOCs, particularly the freely dissolved porewater concentration, however, has been shown to be a good indicator of bioavailability [2][3][4][5].…”

Demonstration and Evaluation of Solid Phase Microextraction for the Assessment of Bioavailability and Contaminant Mobility

“…Assessment of toxicity and bioaccumulation of HOCs with total extractable contaminant concentration in the sediment (i.e. bulk sediment concentration) is unreliable and often provides poor predictions 31 . Sediment porewater concentration of HOCs, particularly the freely dissolved porewater concentration, however, has been shown to be a good indicator of bioavailability 32,33,34,35 .…”