Microplastic Pollution in Residential Soils

The presence of microplastics (MPs) in soil has the potential to cause detrimental impacts to the environment and living organisms. These include alterations to soil characteristics, changes in microbial activity, damage to fauna, and effects on plant growth. However, the existing body of research on microplastics (MPs) in residential soils remains limited. Consequently, the present study sought to identify, quantify the abundance of, and characterise MPs in dense, medium, and low-density residential soils in Sukolilo District Surabaya City, Indonesia. Surface soil samples were collected from three locations, sieved with a 5 mm sieve, and subjected to wet peroxide oxidation (WPO) and filtration in order to separate MPs from the solution. MPs were identified by visual inspection or microscopy, and by Fourier Transform Infrared (FTIR) spectroscopy. The results demonstrated that the highest abundance of MPs was observed in dense residential soils (120.59 n/kg), followed by medium (67.10 n/kg) and low (80.64 n/kg) residential soils. The most prevalent type of microplastic observed was fragments (78.65%), particularly in areas characterised by high population density. The transparent (54.02%) and blue (50.66%) MPs were found to be more abundant than other colours. The most abundant microplastic (MP) size category was the small microplastic (SMP) (< 1 mm), representing 99.91% of the total MP abundance. The most abundant MP type was polypropylene (PP), representing 65.73% of the total MP abundance. This study offers a more nuanced understanding of MP in residential soils, which is related to human activities.