Abstract: An inspection of an already developed QSAR model is necessary to verify the reproducibility of the model itself, and its present applicability to new chemicals, if a version of calculation software for theoretical molecular descriptors is updated. A QSAR model for bioconcentration in fish, published by the authors and based on 5 molecular descriptors of different ...

Abstract: The use of Quantitative Structure?Activity Relationships in assessing the potential negative effects of chemicals plays an important role in ecotoxicology. (LC50)96h in Pimephales promelas (Duluth database) is widely modeled as an aquatic toxicity end-point. The object of this study was to compare different molecular descriptors in the development of new ...

Abstract: This study presents an analysis of the ability of a two-parameter response surface, a multiple linear regression and a neural network model to produce global quantitative structure–activity relationships (QSARs) to predict the toxic potency of phenols to Tetrahymena pyriformis. The phenolic toxicity data set analysed is characterised by multiple mechanisms ...

Abstract: Because of its environmental and industrial importance, the aromatic amines are the single chemical class most studied for its ability to induce mutations and cancer. The large database of mutagenicity and carcinogenicity results has been studied with Quantitative Structure-Activity Relationship (QSAR) approaches by several authors, leading to models for the ...

Abstract: To comply with the REACH (Registration, Evaluation, Authorisation and restriction of Chemicals) regulations, the generation of chronic fish toxicity data is required for chemicals produced or imported within or into the EU in quantities greater than 100 tonnes per year. This comes at a great cost to industry and consumers alike and requires the sacrifice of ...

Abstract: QSARINS (QSAR-INSUBRIA) is a new software for the development and validation of multiple linear regression Quantitative Structure-Activity Relationship (QSAR) models by Ordinary Least Squares method and Genetic Algorithm for variable selection. This program is mainly focused on the external validation of QSAR models. Various tools for explorative analysis of ...

Abstract: The risk of the presence of haloacetic acids in drinking water as chlorination by-products and the shortage of experimental mutagenicity data for most of them requires a research work. This paper describes a QSAR model to predict direct mutagenicity for these chemicals. The model, able to describe more than 90% of the variance in the experimental activity, was ...

Abstract: Chemically reactive, α, β-unsaturated carbonyl compounds are common environmental pollutants able to produce a wide range of adverse effects, including, e.g. mutagenicity. This toxic property can often be related to chemical structure, in particular to specific molecular substructures or fragments (alerts), which can then be used in specialized software or ...

Abstract: The purpose of the analyses presented in this report was to contribute to an evaluation of the possibility of using QSAR predictions for regulatory purposes. To this end QSAR predictions were compared with SIDS test data. Furthermore, the models were also assessed according to the extent to which they meet OECD principles for QSAR validation (OECD ENV/JM/Mon ...

Abstract: All compounds are considered to act by polar narcosis. This is well established for non-reactive compounds. Acute lethality is brought about by accumulation in cellular membranes causing their disruption and ultimately death of the organism. The ability of the compound to accumulate in a cellular membrane is thought to be related to its intrinsic hydrophobicity. ...