title: Aqueous and tissue residue-based interspecies correlation estimation models provide conservative hazard estimates for aromatic compounds.
abstract: Interspecies correlation estimation (ICE) models were developed for 30 nonpolar aromatic compounds to allow comparison of prediction accuracy between 2 data compilation approaches. Type 1 models used data combined across studies, and type 2 models used data combined only within studies. Target lipid (TLM) ICE models were also developed using target lipid concentrations of the type 2 model dataset (type 2-TLM). Analyses were performed to assess model prediction uncertainty introduced by each approach. Most statistically significant models (90%; 266 models total) had mean square errors < 0.27 and adjusted coefficients of determination (adj R(2) ) > 0.59, with the lowest amount of variation in mean square errors noted for type 2-TLM followed by type 2 models. Cross-validation success (>0.62) across most models (86% of all models) confirmed the agreement between ICE predicted and observed values. Despite differences in model predictive ability, most predicted values across all 3 ICE model types were within a 2-fold difference of the observed values. As a result, no statistically significant differences (p > 0.05) were found between most ICE-based and empirical species sensitivity distributions (SSDs). In most cases hazard concentrations were within or below the 95% confidence intervals of the direct-empirical SSD-based values, regardless of model choice. Interspecies correlation estimation-based 5th percentile (HC5) values showed a 200- to 900-fold increase as the log KOW increased from 2 to 5.3. Results indicate that ICE models for aromatic compounds provide a statistically based approach for deriving conservative hazard estimates for protecting aquatic life.
authors.affiliation: Research Planning, Columbia, South Carolina, USA.
authors.forename: Adriana C
authors.initials: AC
authors.lastname: Bejarano
authors.affiliation: US Environmental Protection Agency, Gulf Breeze, Florida, USA.
authors.forename: Mace G
authors.initials: MG
authors.lastname: Barron
mesh_terms: D000465:Algorithms; D000818:Animals; D059001:Aquatic Organisms; D004784:Environmental Monitoring / Q000379:methods / Q000706:statistics & numerical data; D006841:Hydrocarbons, Aromatic / Q000737:chemistry / Q000633:toxicity*; D007928:Lethal Dose 50; D050356:Lipid Metabolism; D008954:Models, Biological; D015203:Reproducibility of Results; D013045:Species Specificity; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*; D014877:Water Pollution, Chemical / Q000009:adverse effects*
chemical_list: D006841:Hydrocarbons, Aromatic; D014874:Water Pollutants, Chemical
keywords: Aromatic compounds; Hazard concentrations; Interspecies correlation estimation; Species sensitivity distributions; Target lipid model