Environmentally relevant mixture of S-metolachlor and its two metabolites affects thyroid metabolism in zebrafish embryos

Pesticide mixture toxicity assessment through in situ and laboratory approaches using embryo-larval stages of the pacific oyster (Magallana gigas)

“…To the best of our knowledge, no other behavioral studies with embryo-larval stages of bivalves exposed to pesticides have been conducted. Concerning other embryo-larval stages, Rozmánková et al (2020) evaluated the effects of SM and its metabolites on total distance swam in light/dark locomotor test of zebrafish (Danio rerio) larvae. This study reported no impact by individual substances (up to 300 µg/L) and also by the mixture of SM, MOA, and MESA (up to 30 µg/L of each substance in the mixture).…”

Occurrence of Pharmaceutical and Pesticide Transformation Products in Freshwater: Update on Environmental Levels, Toxicological Information and Future Challenges

“…Significant decreased of SOD activity at 5 mg/L Chlorella pyrenoidosa Algae growth inhibition rate; content of pigment EC50: 0.13 mg/L; chlorophyll content significantly decreased in dose–response relationship; Fiprunil desulfinyl [fipronil] (Gong et al 2021 ) Danio rerio 0.1 to 10 mg/L 72 h Mortality and oxidative stress LC50 = 1.13 mg/L. Significant decreased of SOD activity at 5 mg/L Chlorella pyrenoidosa Algae growth inhibition rate; content of pigment EC50: 0.43 mg/L; chlorophyll content significantly decreased in dose–- response relationship; Metolachlor OXA [metolachlor] (Velisek et al 2018 ) Procambarus fallax f. virginalis 4.2, 42 and 420 µg/L 45 days Growth rate, behaviour, oxidative stress, histology and mortality Decreased growth and activity of antioxidant enzymes in all tested concentrations; delayed ontogenetic development and lower levels of reduced glutathione and lipid peroxidation Metolachlor OXA [metolachlor] (Rozmánková et al 2020 ) Danio rerio 1, 30, 100 and 300 μg/L (single exposure); 1 and 30 μg/L (mixture) 120 h Mortality, hatching success, embryonic malformations, locomotion, spontaneous movements, heartbeat and gene expression Increased craniofacial, non-inflated gas bladder and yolk sac malformations at 100 μg/L or higher. Induction of p53 gene at 100 μg/L Metolachlor ESA [metolachlor] (Rozmánková et al 2020 ) Danio rerio 1, 30, 100 and 300 μg/L (single exposure); 1 and 30 μg/L (mixture) 120 h Mortality, hatching success, embryonic malformations, locomotion, spontaneous movements, heartbeat and gene expression Increased craniofacial, non-inflated gas bladder and yolk sac malformations at 100 μg/L or higher.…”

“…The highest tested concentrations delayed ontogenetic development and decreased the levels of reduced glutathione and lipid peroxidation (Velisek et al 2018 ). More recently, a study was performed to evaluate the impacts of single and combined exposure of metolachlor and its metabolites metolachlor ESA and metolachlor OXA on zebrafish embryos (Rozmánková et al 2020 ). In this study, zebrafish embryos were exposed for 120 h to 1, 30, 100 and 300 μg/L of the single compounds or to 1 and 30 μg/L of a compound mixture and sublethal endpoints such as malformations, hatching rate, larval length, spontaneous movements, heartbeat and locomotion, as well as expression levels of eight genes linked to different critical pathways, were monitored.…”

“…For metolachlor OXA, a significant induction of p53 gene was found at 100 μg/L, compared to control, whilst for metolachlor ESA, a significant induction of p53 gene at 30 and 100 μg/L and thyroid system regulation (dio2, thra, thrb) was observed at 1 μg/L, in comparison to the control group. The disruption of the thyroid system represented a plausible danger for population maintenance, since it occurred at low environmental concentrations (Rozmánková et al 2020 ). A recent study evaluated the acute toxicity of several biocide metabolites using the rainbow trout ( Oncorhynchus mykiss ) as a test model (Hernández-Moreno et al 2022 ).…”

Análise dos efeitos de agrotóxicos à base de imidaclopride e de abamectina sobre embriões de zebrafish (Danio rerio)

“…[embriotoxicidade, infertilidade e causar defeitos congênitos (Carneiro, 2015;Choudhary et al, 2018;Kumar et al, 2020)], podem ainda agir como desreguladores endócrinos (Choudhary et al, 2018;Rozmánková et al, 2020) ou serem carcinogênicos (Milham, 1971;Carneiro, 2015;Choudhary et al, 2018).…”