title: Predicting algal growth inhibition toxicity: three-step strategy using structural and physicochemical properties.
abstract: We propose a three-step strategy that uses structural and physicochemical properties of chemicals to predict their 72 h algal growth inhibition toxicities against Pseudokirchneriella subcapitata. In Step 1, using a log D-based criterion and structural alerts, we produced an interspecies QSAR between algal and acute daphnid toxicities for initial screening of chemicals. In Step 2, we categorized chemicals according to the Verhaar scheme for aquatic toxicity, and we developed QSARs for toxicities of Class 1 (non-polar narcotic) and Class 2 (polar narcotic) chemicals by means of simple regression with a hydrophobicity descriptor and multiple regression with a hydrophobicity descriptor and a quantum chemical descriptor. Using the algal toxicities of the Class 1 chemicals, we proposed a baseline QSAR for calculating their excess toxicities. In Step 3, we used structural profiles to predict toxicity either quantitatively or qualitatively and to assign chemicals to the following categories: Pesticide, Reactive, Toxic, Toxic low and Uncategorized. Although this three-step strategy cannot be used to estimate the algal toxicities of all chemicals, it is useful for chemicals within its domain. The strategy is also applicable as a component of Integrated Approaches to Testing and Assessment.
authors.affiliation: a Centre for Health and Environmental Risk Research , National Institute for Environmental Studies , Tsukuba , Japan.
authors.forename: A
authors.initials: A
authors.lastname: Furuhama
authors.affiliation: a Centre for Health and Environmental Risk Research , National Institute for Environmental Studies , Tsukuba , Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hasunuma
authors.affiliation: a Centre for Health and Environmental Risk Research , National Institute for Environmental Studies , Tsukuba , Japan.
authors.forename: T I
authors.initials: TI
authors.lastname: Hayashi
authors.affiliation: a Centre for Health and Environmental Risk Research , National Institute for Environmental Studies , Tsukuba , Japan.
authors.forename: N
authors.initials: N
authors.lastname: Tatarazako
mesh_terms: D000818:Animals; D055598:Chemical Phenomena; D000460:Chlorophyta / Q000187:drug effects* / Q000254:growth & development; D003621:Daphnia / Q000187:drug effects; D057927:Hydrophobic and Hydrophilic Interactions; D009294:Narcotics / Q000737:chemistry / Q000633:toxicity; D010575:Pesticides / Q000737:chemistry / Q000633:toxicity; D021281:Quantitative Structure-Activity Relationship; D011789:Quantum Theory; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000633:toxicity*
chemical_list: D009294:Narcotics; D010575:Pesticides; D014874:Water Pollutants, Chemical
keywords: Algal growth inhibition toxicity; Verhaar scheme; category approach; interspecies QSAR; non-polar and polar narcotic; structural alert