title: Novel view on predicting acute toxicity: decomposing toxicity data in species vulnerability and chemical potency.
abstract: Chemical risk assessment usually applies empirical methods to predict toxicant effects on different species. We propose a more mechanism-oriented approach, and introduce a method to decompose toxicity data in a contribution from the chemical (potency) and from the exposed species (vulnerability). We use a database for acute aquatic toxicity, and focus on some well-defined chemical classes. Potency is strongly related to hydrophobicity and vulnerability differences between species are small for narcotic compounds. Potencies show less relation with hydrophobicity and interspecies differences are larger for organophosphate- and carbamate insecticides. Photosynthesis inhibitors generally act narcotic to animals, but were more potent for algae. Using these potencies and vulnerabilities, acute toxicity values were well predicted by the proposed approach (within a factor of 3-6). The proposed approach has potential for predicting toxicity for untested species-compound combinations; however, there is a need for a better definition of 'mode of action' in ecotoxicology.
authors.affiliation: National Institute for Public Health and Environment (RIVM), Laboratory for Ecological Risk Assessment, PO Box 1, NL-3720 BA, Bilthoven, The Netherlands.
authors.forename: Tjalling
authors.initials: T
authors.lastname: Jager
authors.forename: Leo
authors.initials: L
authors.lastname: Posthuma
authors.forename: Dick
authors.initials: D
authors.lastname: de Zwart
authors.forename: Dik
authors.initials: D
authors.lastname: van de Meent
mesh_terms: D000465:Algorithms; D000818:Animals; D002219:Carbamates / Q000633:toxicity; D056890:Eukaryota / Q000187:drug effects* / Q000378:metabolism; D005399:Fishes; D057927:Hydrophobic and Hydrophilic Interactions; D007306:Insecticides / Q000633:toxicity*; D009294:Narcotics / Q000737:chemistry / Q000633:toxicity*; D009943:Organophosphorus Compounds / Q000633:toxicity; D011237:Predictive Value of Tests; D018570:Risk Assessment; D013045:Species Specificity; D023382:Toxicity Tests, Acute; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D002219:Carbamates; D007306:Insecticides; D009294:Narcotics; D009943:Organophosphorus Compounds; D014874:Water Pollutants, Chemical