Bioaccumulation and distribution behavior of endosulfan on a cichlid fish: Differences between exposure to the active ingredient and a commercial formulation.

DA CUÑA, R.; LO NOSTRO, F.; SHIMABUKURO, V.; ONDARZA, P.; MIGLIORANZA, K.

ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY

SETAC PRESS

Lugar: Buenos Aires; Año: 2020 vol. 39 p. 604 - 611

0730-7268

Persistent organic pollutants reach aquatic ecosystems during applicationand can bioconcentrate/biomagnificate due to their lipophilic nature.Toxicological studies focus almost exclusively on the active ingredients(AIs) of pesticides, instead of commercial formulations (CFs), whosetoxicity can differ due to non-specified ingredients. The intensive use ofendosulfan (ES) as a wide range insecticide over the last few decadesmake it one of the most frequently detected contaminants in the aquaticenvironment, even after it has been restricted worldwide. The aim of thisstudy was to evaluate the bioaccumulation and organ distribution ofwaterborne ES in the freshwater fish Cichlasoma dimerus, comparingbetween the AI and a CF. Males were exposed to 0.7 μg.L-1 ES for twoweeks. ES was quantified (GC-ECD) in liver, testes, gills, brain andmuscle. Results suggest rapid metabolization of ES isomers to ES sulfate(ES-S) in tissues. Isomers levels were highest in gills, indicative ofrecent uptake. ES-S levels were highest in liver and testes for the AI,and testes and brain for the CF. For the AI, ES-S levels showed apositive correlation with organ-lipid %. No correlation was evident for CFindicating that the presence of adyuvants alters ES distribution, as gillsand liver showed a higher uptake and mobilization of β-ES. Thesedifferences in organ distribution may alter tissue-specific toxicity,therefore additives cannot be considered inactive even if non-toxic.