Comparing in vivo data and in silico predictions for acute effects assessment of biocidal active substances and metabolites for aquatic organisms

• Published in: Ecotoxicology and environmental safety Vol. 205; p. 111291
• Main Authors: Blázquez, María, Andreu-Sánchez, Oscar, Ranero, Irati, Fernández-Cruz, María Luisa, Benfenati, Emilio
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.12.2020
• Subjects: Acute toxicity; Biocides; Daphnia; Freshwater microalgae; QSAR; STP microorganisms; Daphnia; Freshwater microalgae; STP microorganisms; QSAR; Biocides; Acute toxicity
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2020.111291

The purpose of this study was to determine the acute toxicity in aquatic organisms of one biocidal active substance and six metabolites derived from biocidal active substances and to assess the suitability of available QSAR models to predict the obtained values. We have reported the acute toxicity in sewage treatment plant (STP) microorganisms, in the freshwater microalgae Pseudokirchneriella subcapitata and in Daphnia magna following OECD test methods. We have also identified in silico models for acute toxicity of these trophic levels currently available in widely recognized platforms such as VEGA and the OECD QSAR ToolBox. A total of six, four and two models have been selected for Daphnia, algae and microorganisms, respectively. Finally, we have compared the in silico and in vivo data for the seven compounds plus two previously assayed biocidal substances. None of the compounds tested were toxic for Daphnia and STP microorganisms. For microalgae, CGA71019 (1,2,4 triazole) presented an ErC50 value of 38.3 mg/L. The selected in silico models have provided lower EC50 values and are therefore more conservative. Models from the OECD QSAR ToolBox predicted values for 7 out of 9 and for 4 out of 9 chemicals for Daphnia and P. subcapitata, respectively. No predictive models were identified in such platform for STP microorganism's acute effects. In terms of models's specificity, biocide-specific models, developed from curated datasets integrated by biocidal active substances and implemented in VEGA, perform better in the case of microalgae but for Daphnia an alternative, non biocide-specific has revealed a better performance. For STP microorganisms only biocide-specific models have been identified. [Display omitted] •In vivo acute effects of one biocide and six metabolites for Daphnia, algae and microorganisms.•The compounds were nontoxic for microorganisms and Daphnia; one was toxic for algae.•Comparison with values predicted with different models included in VEGA and OECD QSAR ToolBox.•Best performing models identified.•Models implemented in VEGA provide a more complete perspective.