ABSTRACT:

The present study evaluated the amount and types of microplastics (MP) in ten wells where drinking water is extracted for human consumption and domestic activities of two rural communities of the State of Tlaxcala: San Diego Xocoyucan and Ixtacuixtla, Mariano de Matamoros, México. For groundwater sampling, the possible aerial deposition of microplastics was considered; in each well, two samples were taken, one of surface water (from the first 5 cm of depth) and another of water without contact with air; the last one was obtained with a fountain pump submerged into the deepest part of the wells. In both cases, samples were filtered in situ with a number 35 sieve. The average abundance of microplastics was 0.34 MP/L, and there was no difference between the communities. The MPs measured 2,100 to 4,400 μm in length, averaging 2,995 ± 437. 100% of the MP found were fragments. Regarding color abundance, black > white > blue > green > gray coincided in both communities. The polymers found were nylon, High Density Poly Ethylene (HDPE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyethylene terephthalate (PET). Seasonally, there were no differences in the abundance of MP by aerial deposition. However, the groundwater deep in the wells presented a statistical difference with the highest abundance in the dry season (Ixtacuixtla 0.49 MP/L; Xocoyucan 0.47 MP/L), which indicates that rainwater dilutes this pollution (Ixtacuixtla 0.36 MP/L; Xocoyucan 0.34 MP/L). The communities of San Diego Xocoyucan, Tlaxcala and Ixtacuixtla de Mariano Matamoros, Tlaxcala, generate domestic, agricultural and industrial waste. Even more, there is no efficient management of urban solid waste, as well as wastewater; All of the above generates the state of plastic pollution in the region and therefore its groundwater.