title: Toxmatch--a chemical classification and activity prediction tool based on similarity measures.
abstract: Chemical similarity forms the underlying basis for the development of (Quantitative) Structure-Activity Relationships ((Q)SARs), expert systems and chemical groupings. Recently a new software tool to facilitate chemical similarity calculations named Toxmatch was developed. Toxmatch encodes a number of similarity indices to help in the systematic development of chemical groupings, including endpoint specific groupings and read-across, and the comparison of model training and test sets. Two rule-based classification schemes were additionally implemented, namely: the Verhaar scheme for assigning mode of action for aquatic toxicants and the BfR rulebase for skin irritation and corrosion. In this study, a variety of different descriptor-based similarity indices were used to evaluate and compare the BfR training set with respect to its test set. The descriptors utilised in this comparison were the same as those used to derive the original BfR rules i.e. the descriptors selected were relevant for skin irritation/corrosion. The Euclidean distance index was found to be the most predictive of the indices in assessing the performance of the rules.
authors.affiliation: Institute for Health and Consumer Protection, Joint Research Centre-European Commission, 21027 Ispra (VA), Italy. annag@iqc.udg.es
authors.forename: Ana
authors.initials: A
authors.lastname: Gallegos-Saliner
authors.forename: Albert
authors.initials: A
authors.lastname: Poater
authors.forename: Nina
authors.initials: N
authors.lastname: Jeliazkova
authors.forename: Grace
authors.initials: G
authors.lastname: Patlewicz
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Worth
mesh_terms: D006801:Humans; D007509:Irritants / Q000737:chemistry* / Q000145:classification / Q000633:toxicity; D021281:Quantitative Structure-Activity Relationship; D012867:Skin / Q000187:drug effects; D023422:Skin Irritancy Tests / Q000379:methods; D012984:Software; D014116:Toxicology / Q000379:methods
chemical_list: D007509:Irritants