CHALLENGES FOR DETECTING MICROPLASTICS IN FISH

Resumo

INTRODUCTION: Consumption of fish has been increasing, but concern about contamination by microplastics (MPs) has gained prominence in the scientificcommunity, since it can interfere with the quality of fish meat and the population'sdietary pattern. The lack of public policies and proper management of plastic wasteinBrazil directly implies contamination of environmental matrices and promotesbioaccumulation in river basins. This is due both to the lack of support fromBrazilianenvironmental legislation and the lack of standardised methodologies for detectingMPcontaminants in the aquatic environment and in foodstuffs such as fish. The MPs aresmall structures derived from the fragmentation of plastic, which, when ingested byfish, can also contaminate humans and trigger various health problems. OBJECTIVES: Inthis context, this study compared the efficiency of methodologies for detecting MPs inorder to corroborate their detection, identification and quantification. MATERIALANDMETHODS: The protocols used to digest the intestinal tract of fish are time-consumingand require several steps. In this study, three parts of the fish were digested: thegastrointestinal tract, gills and fat of Pseudoplatystoma corruscans species acquiredbylocal fishermen in Aruanã-GO. A 10% potassium hydroxide (KOH) solutionwasprepared at room temperature for three weeks until the organic matter was completelydigested (Foekema et al., 2013). In parallel, another method was used, combininga35% solution of hydrogen peroxide (H2O2) and 4% potassium hydroxide (KOH) at 60ºCfor 72 h; 10:40 of 68% perchloric acid (HClO4) and 65% nitric acid (HNO3) were added(Abbasi et al., 2018). After vacuum filtration, it was visualised under astereomicroscope. RESULTS AND CONCLUSION: According to the analysis, microplastic particles were found in all the samples in both methods. Thus, the most viable, economical and safe method was digestion with 10% KOH, as proposedby(Foekema et al., 2013). Therefore, the applicability of this method was possible; thereisan urgent need to implement public policies in Brazil against the improper disposal of plastic waste, to establish methodological standards for monitoring and controllingplastic pollution in the aquatic environment, and to raise public awareness about fishquality.