Human health risk perspective study on characterization, quantification and spatial distribution of microplastics in surface water, groundwater and coastal sediments of thickly populated Chennai coast of South India

Abstract

Microplastics (MPs) are defined as plastic particles smaller than 5 mm in size. They are primarily derived from larger pieces of plastic debris that degrade into smaller pieces. The current study identified, characterized, and quantified MPs in Chennai coast coastal aquifers, seawater, and foreshore sediments. The spatial distribution and polymer composition of MP particles were studied to identify and evaluate their abundance and characteristics (composite, size, color, and shape of MPs). The foreshore and river mouth sediment samples were found to be contaminated by MPs with a total of 263 particles in 12 samples collected from different locations (average of 22 particles 5 g⁻¹ of dry sediment (d.s.)). The surface water and groundwater samples were also contaminated by MPs with a total of 315 particles in 25 samples collected from different locations (average of 13 particles/L). Size of majorities of MPs ranged from 1 mm to 300 μm. The study also confirmed the presence of MPs in sediments and water samples collected from the study area using Fourier transform infrared spectroscopy (FTIR). FTIR results revealed that nylon, polyvinylchloride, and polyethylene terephthalate were the predominant types of MPs. The spatial variation map showed that high concentration of MPs was observed on tourist beaches. Remediation technologies are highly effective in eliminating and preventing MPs pollution in our environment. The existence of MPs in water samples suggests that it is essential to take preventive steps to avoid MPs causing health issues like neurotoxicity, Alzheimer, and cancer.

Keywords:

• microplastics
• surface and subsurface water
• coastal and river mouth sediments
• health risks
• remediation
• Chennai coast
• South India