Interaction of Heavy Metals with Plastic Contaminated Soil

Abstract

Microplastic (MP) contamination is a threat to soil and groundwater system. Disintegration of used plastic products under exposure to solar radiations, application of sewage sludge to the soil, plastic mulching in agricultural activities leads to the formation of microplastics in significant amounts in soil. Hence there is a need from the geo environment engineering perspective on microplastic contamination in soils. Landfills and industrial areas have microplastic pollution in abundance. The presence of microplastic may alter the behaviour of liner material and surface soil in terms of heavy metal retention capacity, shrinkage, permeability and various other properties. In the present study, the soil is artificially polluted with shredded polypropylene (Pp) fragments from single use facial mask which is extensively being used in post COVID-19 situation. Heavy metals such as Lead, Nickel, Copper and Zinc at different concentrations similar to an industrially polluted soil is applied to the plastic contaminated (Pc) and normal soil. The filtrates from the test batches are studied for Total Dissolved Solids (TDS) and concentration of heavy metals using Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES). The obtained results concluded that plastic pollution significantly varied leached out heavy metals concentration to a maximum of 4.9 times that of normal soil. The TDS of the filtrate collected from plastic polluted soil varied by 31.29%.