Evaluation of the biological effects of microplastic, triclosan and 17α ethinylestradiol interaction in tropical estuarine species: An ecotoxicological approach.

Author(s)

Caio Rodrigues Nobre

• Document type: Doctoral Thesis
• Press: São Vicente. 2022-05-17.
• Institution: Universidade Estadual Paulista (Unesp). Instituto de Biociências. São Vicente
• Defense date: 2022-03-31
• Advisor: Camilo Dias Seabra Pereira; Paloma Kachel Gusso Choueri

Abstract

Domestic wastewater is a complex mixture of different substances, including microplastics and pharmaceuticals and personal care products (PPCPs). Microplastics have affinity with hydrophobic substances such as the synthetic hormone 17α ethinyl-estradiol or the antimicrobial triclosan, and can interact in aquatic environments acting as vectors for the dispersion of these substances, with potential synergistic or additive effects. In this context, the present study aims to assess the environmental risk of microplastics as vectors of PPCPs through an ecotoxicological approach using estuarine organisms. The oyster (Crassostrea brasiliana), crab (Ucides cordatus) and fish (Centropomus undecimalis) organisms were exposed to treatments: control (C); contamination-free microplastics (MP); and microplastic contaminated with 17α ethinyl estradiol (MPE); microplastic contaminated with triclosan (MPT). The organisms were exposed for 3 and 7 days. For oysters and crabs, after exposure to 10 organisms/treatment/time, their cellular health was evaluated using the lysosomal membrane stability assay in hemolymph. After the end of the trials, tissues of 7 organisms were also separated for the analysis of biochemical biomarkers (EROD, DBF, GST, GPx, GSH, LPO, DNA damage and ChE) in oysters (gills, digestive glands and adductor muscles), crabs (gills, hepatopancreas and muscles) and GST, GPx, GSH, LPO, DNA damage and ChE in fish (gills, liver, intestine, muscle and brain). The 3 remaining organisms of each species were separated for analytical determinations at the levels of 17α ethinyl estradiol and triclosan. Both the substances evaluated EE2 and TCS had their presence detected in the water and in the exposed organisms. When inserted in the experimental medium, the polyethylene particles without contamination and contaminated with EE2 and TCS were able to promote biochemical effects on phase I, phase II enzymes, anti-oxidant system, lead to oxidative stress and trigger DNA damage and neurotoxic and cytotoxic effects in the three model species C. brasiliana, U. cordatus and C. undecimalis in the different tissues evaluated. When comparing the effects of substances adsorbed by MPs, TCS, even at lower concentrations, was more toxic than EE2 for the model species. When the organisms were compared with each other, the species factor proved to be the most relevant for the occurrence of PM effects in general. Based on the data obtained, it is possible to infer that the polyethyne microplastics associated with FPCPs 17α ethinyl-estradiol and triclosan pose a risk to tropical estuarine ecosystems and the species Crassostrea brasiliana, Ucides cordatus and Centropomus undecimalis can generate ecological disturbances to the estuarine food chain. (AU)

• FAPESP's process: 17/12193-9 - EVALUATION OF THE ENVIRONMENTAL RISK OF THE INTERACTION OF MICROPLASTIC, DRUG AND ANTIMICROBIAL: AN ECOTOXICOLOGICAL APPROACH
• Grantee: Caio Rodrigues Nobre
• Support Opportunities: Scholarships in Brazil - Doctorate