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Title: {Sigma}PAH: A model to predict the toxicity of polynuclear aromatic hydrocarbon mixtures in field-collected sediments

Journal Article · · Environmental Toxicology and Chemistry
; ; ; ; ;  [1];  [2];  [3]
  1. Environmental Protection Agency, Newport, OR (United States)
  2. Oregon State Univ., Corvallis, OR (United States)
  3. AScI Corp., Newport, OR (United States)

The {Sigma}PAH model estimates the probability of toxicity of PAH-contaminated sediments using a combination of equilibrium partitioning, WSAR, toxic unit, additivity, and concentration-response models. The sediment concentration of organic carbon and 13 PAH (polynuclear aromatic hydrocarbon) compounds were measured. Interstitial water concentrations (PAH{sub iw}) of the 13 compounds were predicted by equilibrium partitioning. The 10-d LC50 of each compound in interstitial water (10-d LC50{sub iw}) was predicted by a QSAR regression of 10-d LC50{sub iw} (From spiked sediment tests) to K{sub ow}. Toxic unit concentrations of individual compounds (TU{sub i}) were predicted as PAH{sub iw}/10-d LC50{sub iw}. The total number of toxic units of the 13 compounds ({Sigma}TU{sub i}) was calculated assuming the additivity of toxic effects of PAHs. {Sigma}TU{sub i} was used to predict the probability of toxicity to marine and estuarine amphipods using a concentration-response model derived from spiked sediment toxicity tests. The {Sigma}PAH model was verified by comparing predicted and observed toxicity in field-collected sediment samples. There was 86.6% correspondence and no significant difference between predicted and observed toxicity at PAH-contaminated sites. Ecological-effect levels predicted by the {Sigma}PAH model correspond with several sediment-quality guidelines.

Sponsoring Organization:
USDOE
OSTI ID:
136755
Journal Information:
Environmental Toxicology and Chemistry, Vol. 14, Issue 11; Other Information: PBD: Nov 1995
Country of Publication:
United States
Language:
English