Microplastic contamination in bathhouses in the middle Amazon region, Itacoatiara, Brazil

Abstract The number of investigations has increased worldwide about the abundance and distribution of microplastics in different water bodies and biota. This study investigated microplastic contamination in bathhouses in the Middle Amazon, in Itacoatiara, AM, Brazil. A total of 202 microplastic particles were recorded in the five investigated areas used for recreation. These results indicate no significant difference in the number of microplastic particles between bathhouses (KW = 7.4805; P = 0.1126). The size of the microplastic particles differed significantly between the bathhouses (KW = 40.9582; P = 0.0001). Both blue and red microplastic particles were recorded, with blue particles being the most abundant. The microplastic particles were in the form of fibers and fragments. The number of microplastic particles (U = 7.4686; P = 0.0001) was significantly different between the areas within and adjacent to the bathhouses; however, the size of microplastic particles were not significantly different in the areas within and areas adjacent to the bathhouses (U = 0.6505; P = 0.5154). There was no significant correlation in the bathhouses between their frequency of use and contamination (number of microplastic particles) (rs = 0.4472; P = 0.4502). The results of this study indicate that microplastics are present in the bathhouses of the Middle Amazon and that contamination in areas used for recreation is significantly higher than in areas not used for this purpose.