We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Ecological footprint of microplastics in coastal and estuarine environments of India: Sediment-water interface analysis
Summary
This study mapped microplastic pollution across 16 coastal and estuarine sites along India's coastline, finding contamination everywhere with concentrations varying based on local human activities like port operations, tourism, and fishing. The microplastics were mostly small fibers and fragments under 500 micrometers, and certain plastic types were especially good at absorbing heavy metals. This means microplastics in coastal waters serve as carriers that can transport toxic metals into the seafood chain and ultimately into human diets.
Understanding the distribution and characteristics of microplastics (MPs) in varied aquatic ecosystems is essential for assessing their environmental impact. This study investigates microplastic pollution across 16 coastal and estuarine sites along the Indian coastline, spanning distinct marine regimes including the Bay of Bengal, Arabian Sea, and Gulf of Mannar, aiming to compare site-specific contamination and assess the potential of plastic debris to act as vectors for associated heavy metals. MP abundance in surface water and sediment ranged from 1.1 to 4.8 particles/L and 416.7-983.3 particles/kg, respectively, reflecting strong spatial heterogeneity driven by site specific human activity (port operations, tourism, fishing etc.), hydrodynamics, and ecological conditions. MPs were primarily fibres and fragments <500 μm in size, with black, white, and blue being the most common colours. SEM-EDS analysis qualitatively indicated surface weathering and the presence of elements on microplastic surfaces, particularly in fragments, which showed greater potential for heavy metal adsorption compared to fibres. Raman spectroscopy identified 12 polymer types in MPs and 10 in macro-plastic debris, with common polymers (e.g., PP, PS, PES, PU, and PE) suggesting shared sources. ICP-OES results confirmed that certain polymers (notably PES and HDPE) retained substantial amounts of metals such as Fe, Zn, Mg, and Ca, highlighting polymer-specific sorption behaviour which is strongly influenced by natural availability as well as different ionic states of metals, polymer-specific surface chemistry, degree of environmental weathering, and surface morphology. Pollution Load Index (PLI) values ranged 1.0-2.045 across different study sites, identifying several regions as pollution hotspots. Overall, this study not only quantifies MP pollution but also links polymer-specific properties to metal retention potential, highlighting the dual threat of MPs as both physical and chemical pollutants in Indian aquatic environments.
Discussion
Log in to join the discussion
Sign in