Microplásticos em água potável e de abastecimento: eficiência de remoção em estações de tratamento e potenciais riscos à saúde.

Abstract

Microplastics (MPs) have garnered global attention as persistent emerging pollutants and that pose a threat to the environment. In addition to causing various physical and biological effects, they can act as adsorbents for hazardous contaminants. Recently, studies have detected their presence in both raw and treated water from drinking water treatment plants (DWTPs), highlighting a potential risk to human health. The study quantifies microplastics based on their shape and color, analyzes seasonal variations in supply water, evaluates the removal efficiency of microplastics in DWTPs, and estimates the daily and annual intake of these pollutants through drinking water. To achieve these objectives, surface water (SW), water column (WC), and treated drinking water (DW) samples were analyzed during both the dry and rainy seasons using a combination of sieving, density separation, digestion, oxidation, vacuum filtration, and optical microscopy techniques. Microplastics were found in all water samples, in both dry and rainy periods, with average concentrations ranging from 294 ± 73 to 118 ± 41 MPs/L in SW, from 164 ± 42 to 105 ± 35 MPs/L in WC, and from 48 ± 11 to 28 ± 12 MPs/L in DW. The comparison of samples before and after treatment showed that 68% of the particles were removed at the DWTP. The estimated daily intake for children was 2.8 ± 1.6 MPs/kg/L/day, totaling 1038 ± 590 MPs/kg/L/year, and for adults, 1.2 ± 0.6 MPs/kg/L/day, totaling 427 ± 228 MPs/kg/L/year. This study contributes to bridging the knowledge gap regarding emerging microplastic pollution in drinking water and freshwater sources, which is of concern due to the potential for human exposure to these pollutants.