Avoidance responses by Danio rerio reveal interactive effects of warming, pesticides and their mixtures

• Published in: The Science of the total environment Vol. 847; p. 157525
• Main Authors: Moreira, Raquel A., Cordero-de-Castro, Andrea, Polo-Castellano, Curro, Pinto, Thandy J.S., Dias, Mariana A., Montagner, Cassiana C., Espíndola, Evaldo L.G., Araújo, Cristiano V.M., Blasco, Julián
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.11.2022
• Subjects: 2,4-D; Climate change; Fipronil; Habitat disturbance; HeMHAS; Pesticide mixture; Pesticide mixture; Climate change; HeMHAS; Habitat disturbance; 2,4-D; Fipronil
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2022.157525

Temperature variations and thermal extremes events caused by climate change can have profound implications for the toxicity of pesticides in aquatic organisms. Using an innovative system (Heterogeneous Multi-Habitat Test System - HeMHAS) that allows the simulation of different scenarios within a spatially heterogeneous landscape, the effects on the habitat selection of Danio rerio fish caused by the pesticides fipronil and 2,4-D were studied as single compounds and in mixture and integrated with air temperature variation (20, 24 and 28 °C). As a result, D. rerio detected and avoided both pesticides at air temperatures of 20 and 24 °C; however, at 28 °C no significant difference was observed in habitat choice by fish. Additionally, when pesticides were mixed in a heterogeneously contaminated landscape, it was observed that D. rerio detected contamination and preferred the clean zone at 20 and 24 °C; however, at 28 °C the potential to escape from the most contaminated areas was impaired. Thus, contamination by both pesticides made the habitat selection behavior of fish at 20 and 24 °C more noticeable. In addition, the association between pesticides and temperature showed negative effects on the response of fish to detect and escape from contaminated environments, suggesting the influence of temperature in altering the ability of the organism to provide an efficient response to stress. [Display omitted] •D. rerio avoided contamination by fipronil and 2,4-D at 20 and 24 °C, but not at 28 °C.•D. rerio preferred clean areas to pesticide mixtures at 20 and 24 °C, but not at 28 °C.•Temperature influences the ability of D. rerio to respond efficiently to stress.•HeMHAS showed to be an efficient system to assess chemically heterogeneous areas.