Ecotoxicological effects of the microplastic polyethylene and the pesticide imidacloprid, alone and in a mixture, on the aquatic invertebrates Daphnia similis (Cladocera) and Hyalella meinerti (Amphipoda)

• Grant number: 24/00791-2
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: May 01, 2024
• End date: February 28, 2027
• Field of knowledge: Biological Sciences - Ecology - Applied Ecology
• Principal Investigator: Evaldo Luiz Gaeta Espindola
• Grantee: David Silva Alexandre
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 22/12104-4 - Fate and impacts of microplastics and pesticides in aquatic and terrestrial matrices in agricultural contexts, AP.TEM
• Associated scholarship(s): 24/16532-6 - Cytotoxic effects of polyethylene microplastics isolated and mixed with the pesticides imidacloprid and tebuconazole on fish: an in vitro approach, BE.EP.DR

Abstract

Since 1950, global plastics production has reached 8.9 billion tonnes, with 2.6 billion still in use and 6.3 billion discarded. In 2018, Brazil contributed 11.3 million tons of plastic waste, ranking it as the fourth largest producer in the world. Furthermore, the country leads the global consumption of pesticides, totaling approximately 130 thousand tons annually. Given this scenario, it is crucial to understand the effects of these contaminants on the ecosystem and non-target species. Therefore, this research aims to investigate the ecotoxicological effects of polyethylene microplastic (MP) and the insecticide imidacloprid, alone and in mixture, on the species Daphnia similis (Crustacea: Cladocera) and Hyalella meinerti (Crustacea: Amphipoda). The project will be divided into three parts. In the first stage, in situ bioassays will be conducted in mesocosms at four different times (one, twenty, forty and sixty days after contamination with both contaminants), using the species H. meinerti as a test organism. The assessment will cover parameters such as survival, microplastic ingestion, acetylcholinesterase (AChE) biomarkers and determinations of energy reserves (carbohydrates, lipids and proteins), as well as biomass and growth analyses. In the second part, ex situ tests will be carried out, with the simultaneous collection of water and sediment samples at eight different time intervals (one day before contamination with polyethylene; one, seven and fourteen days after; as well as one, seven and fourteen days after contamination with imidacloprid and, finally, on the last day of the experiment) with a view to carrying out ecotoxicological tests. Given the epibenthic habits observed only in the species H. meinerti, ecotoxicological tests will be conducted with both matrices (water and sediment), evaluating the endpoints survival, swimming behavior, reproduction, ingestion of polyethylene microparticles, couple formation, biomarkers ( AChE, carbohydrates, proteins and lipids), biomass and growth. For the species D. similis, tests will be carried out only with water samples, evaluating survival, deformity, reproduction, MP intake and biomarkers (AChE, carbohydrates, proteins and lipids). The third part will include toxicokinetic studies, a step scheduled to take place during the exchange period (BEPE-FAPESP) at Wageningen University & Research, Netherlands, under the supervision of researcher Dr. Paul J. Van den Brink, coordinator of Aquatic Ecology and Water Quality Management Group. Based on the results obtained in the tests and statistical analyzes applied, this project aims to understand the effects of polyethylene MP alone and in mixture with the pesticide imidacloprid on species of aquatic crustaceans, as well as identifying the associated environmental risks.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ALEXANDRE, DAVID SILVA; OGURA, ALLAN PRETTI; MOHEDANO, RODRIGO DE ALMEIDA; THIBAU, LORENA BITTENCOURT GUIMARAES. Potential of two floating aquatic macrophytes in improving water quality: A case study in two tropical streams. REVISTA BRASILEIRA DE CIENCIAS AMBIENTAIS, v. 60, p. 14-pg., 2024-01-01. (24/00791-2, 21/14789-1)

DA COSTA, VANESSA BORGES; OGURA, ALLAN PRETTI; ALEXANDRE, DAVID SILVA; SOARES, MATHEUS BORTOLANZA; ALLEONI, LUIS REYNALDO FERRACCIU; ESPINDOLA, EVALDO LUIZ GAETA; DA SILVA PINTO, THANDY JUNIO. How much biochar is safe? Exploring potential ecotoxicological consequences for soil invertebrates and plants. APPLIED SOIL ECOLOGY, v. 202, p. 9-pg., 2024-07-30. (22/08032-8, 22/14293-9, 24/00791-2, 21/14789-1)