Measurement of baseline toxicity and QSAR analysis of 50 non-polar and 58 polar narcotic chemicals for the alga Pseudokirchneriella subcapitata

Linking algal growth inhibition to chemical activity: Baseline toxicity required 1% of saturation

“…In a recent study, Aruoja and co-workers (Aruoja et al, 2014) The interpretation of toxicity data on a chemical activity basis can be achieved using an 72 approach that is both relatively simple and elegant. Specifically, when a liquid compound is 73 dissolved in water, and has limited water solubility (S water ), the ratio of EC 50 /S water provides …”

Interspecies quantitative structure–activity–activity relationships (QSAARs) for prediction of acute aquatic toxicity of aromatic amines and phenols

“…Although the training datasets in this study focused on chemicals with relatively low molecular weights (≤364.9), the log P(1) -log D > 1 criterion can be expected to be applicable for chemicals with molecular weights of >364.9. Our QSAARs had lower goodness-of-fit and prediction ability than the algae models introduced by Aruoja et al [38], whose dataset consisted of 58 nonpolar and 50 polar narcotic chemicals. One reason for our poorer results is that the descriptors used in the Aruoja model [38] consisted of not only hydrophobicity or molecular size but also electronic or molecular stability effects, which were based on quantum chemical calculations.…”

“…Leverage criteria ('warning leverages' [35,36]), h* values, were calculated as 3(k + 1)/n, where k and n are the number of descriptors and the number of training data, respectively. We constructed the leverage values and the h* criteria by following the instructions of Jaworska et al [37], Aruoja et al [38] and other authors [35,36].…”

“…This was because chemical F has a fluorobenzene substructure, which is not covered by any of the indicator variables and is not in the training dataset. Aruoja et al [38] also cautioned that the applicability domain of a proposed alga multi-linear QSAR was largely defined by the structural constitution of the training set and that substitution pattern should therefore be considered when applying the model.…”

Investigation on modes of toxic action to rats based on aliphatic and aromatic compounds and comparison with fish toxicity based on exposure routes

“…Baseline toxicity is associated with chemicals acting by narcosis mechanism which is the reversible suppression of physiological function brought about by hydrophobic binding of chemicals to cell membranes and proteins. Because these weak interactions impact countless membranes and proteins non-specifically, normal physiological functions decline and lethality is approached for a broad array of chemical structures (Veith et al, 2009;Aruoja et al, 2014). It has been estimated that about 70% of monomeric industrial organic compounds exert their toxicity to aquatic organisms via the narcosis mechanism (Bradbury and Lipnick, 1990).…”