Fish cell lines as screening tools to predict acute toxicity to fish of biocidal active substances and their relevant environmental metabolites

• Published in: Aquatic toxicology 2022-01, Vol.242, p.106020, Article 106020
• Main Authors: Hernández-Moreno, D, Blázquez, M, Navas, JM, Fernández-Cruz, ML
• Format: Article
• Language: English
• Subjects: Animals; Aquatic; Biocide; Cell Line; Cyprinodontiformes; Cytotoxicity; Degradation product; Disinfectants; In vivo; Oncorhynchus mykiss; Screening; Toxicity Tests, Acute; Water Pollutants, Chemical - toxicity
• ISSN: 0166-445X; 1879-1514
• DOI: 10.1016/j.aquatox.2021.106020

•Toxicity data for 7 biocides or metabolites in rainbow trout and 16 in fish cells.•Correlation of data in fish cell lines versus fish for 46 substances.•Approach using different fish cell lines and endpoints and categorization of data.•Good predictions for the high toxic substances (100% of coincidence).•Same categorization in terms of toxic/non-toxic for 85% of the substances. Biocidal substances and their environmental relevant metabolites are highly toxic for fish. However, an important scarcity of toxicity data for metabolites is recognised. This article provides new data about the toxicity to fish of these compounds and evaluates the potential use of fish cell lines as screening tools to assess the acute toxicity of these compounds in fish. To this aim, acute toxicity of 7 substances was tested in Oncorhynchus mykiss (OECD TG203) and cytotoxicity of 16 substances was assessed in fish cell lines from two species; Poeciliopsis lucida (PLHC-1) and O. mykiss (RTH-149, RTG-2 and RTgill-W1) performing three cytotoxicity tests: Alamar-Blue, 5-carboxyfluorescein diacetate, acetoxymethyl ester and Neutral Red Uptake. Additionally, in vitro and in vivo data from the LIFE-COMBASE database were included in a dataset finally comprising 33 biocides and 14 metabolites. Hazard data were categorized into 4 toxicity groups, according to the intervals established in Regulation (EC) 1272/2008. Finally, the Spearman correlation test was performed and coincidences between in vitro-in vivo data established. In vitro and in vivo results revealed a high positive correlation, with a complete coincidence for 56.5% of the substances, a 2% of false positives (non-toxic in vivo) and a 13% of false negatives (toxic in vivo) for the 4 toxicity categories. However, when results were grouped in toxic or non-toxic coincidence was obtained for 85% of the substances. In conclusion, although fish denote a greater sensitivity, the use of at least two fish cell lines and three cytotoxicity endpoints appear to be valid approaches for fish acute toxicity screening of biocides and their metabolites.