Quantitative analysis of microplastic particles in digestive system of peasant work bees Scaptotrigona postica (Hymenoptera: Apidae)

Abstract

Microplastics are emergent contaminants that can be found in marine and terrestrial ecosystems. Same as non-particulate plastics, microplastics can bring a lot of problems to environment by carrying and releasing toxic substances to animals, like bisphenol A and other organic toxicants that can be absorbed by microplastics (persistent organic pollutants - POPs). Despite the bees being terrestrial organisms, they are bioindicators of fresh water pollution and in a variety of geobotanical landscapes, once they are the main phanerogamous plants pollinators. Because of that characteristics, they are subject to intoxication by various xenobiotics, either by contact or indirect ingestion. Although the toxicologic importance of microplastics in fresh water bodies, there isn't studies about their presence in bee's digestive system. Therefore, is proposed an analysis of microplastics presence in peasant works bee's intestines of Scaptotrigona postica species. The study will be made by collecting 60 bees in field, for dissection and digestion of their digestive system, in a solution composed of KOH and H2O2. The solutions resultant from the digestion of the digestive system, will be used for a quantitative analysis, in Neubauer's Chamber, of microplastics per mm3 of intestines. Will be made quantitative analysis (polarity and hydrophobia), using a fluorescence microscope with green specter filter, the solutions will be died with Nile red and the fluorescence index, R= (G + B)/R, will be calculated. It will be used Milli-Q water as control in the experiment and in the digestion solutions, to ensure that will not be microplastic contaminants in the sample. It's important to accentuate that this is the first study to propose this investigation and methodology on bees in the current literature, therefore the originality of the project can bring great impacts in the bees ecotoxicology area.