Análise quali-quantitativa de microplásticos em ecossistema aquático sob influência das atividades antrópicas

Abstract

Pollution of water bodies by microplastics has become a major environmental problem. In this sense, the aim of the study was to qualitatively analyze the incidence of microplastics in the aquatic ecosystem under the influence of human activities. The study was developed at Córrego do Barbado, located in Cuiabá-MT. The analysis of environmental integrity was composed of demographic density, land use and occupation, deforestation (vegetation cover) and urban solid waste management. For the analysis of microplastics in washing water, water and stream sediment, collections were performed at four sample points. The obtaining of microplastics in washing water was through the collection of three vials of 1 liter each in homes, to obtain microplastics in the stream water, 100 liters were collected in triplicate per sampling point and to obtain microplastics in the sediment. 1 kilogram of sample was collected, consisting of a sampling point. For the processing of the samples, granulometric sieves, saline solution and hydrogen peroxide were used. Microplastics were manually quantified by separating them with the aid of a needle forceps using a stereoscope. The results of environmental integrity showed that there are factors that cooperate for the environmental degradation of the stream, requiring measures for environmental education and awareness, in addition to inspection and monitoring of the stream. All the samples of the washing water had microplastics, specifically fibers, mostly green and black. For the physical and chemical parameters the results of electrical conductivity, dissolved oxygen, total solids and turbidity demonstrated the pollution of the water body. The incidence of microplastics in water was higher than the amount of microplastics in the sediment and the highest amounts of microplastics were found in May for both water and sediment. As for the type of microplastic, the majority found was fiber and the predominant color of the microplastics found was blue. In view of the above, it is concluded that the Barbado Stream, over the years, has suffered direct and indirect influence from human activities, affecting environmental integrity around the watershed, as well as altering water quality. In addition, microplastics are present in large quantities, both in water and in sediment, directly affecting the entire ecosystem.