Key Terms & Concepts — UPSC Mains
Microplastics
"Plastic particles less than 5 mm in size, either manufactured at that size or created by fragmentation of larger plastics, found in oceans, soil, air, and human tissue"
Microplastics are plastic particles smaller than 5 millimetres in any dimension. They are classified as primary (manufactured at micro-scale, microbeads in cosmetics, plastic pellets) or secondary (fragmented from larger plastic debris through UV exposure, wave action, or mechanical abrasion). Nanoplastics are a subset below 1 micron. Microplastics have been detected in every ecosystem on Earth, deep ocean trenches, Arctic ice, Himalayan snow, agricultural soil, drinking water, human blood, placentas, and lungs.
UPSC relevance in GS3 (Environment, pollution, marine ecosystems) and GS2 (Governance, plastic regulation, Extended Producer Responsibility). India's 2025 Sundarbans study (UNESCO) detected microplastics in mangrove sediments, linking plastic pollution to blue carbon ecosystem degradation. India's single-use plastic ban (2022) and EPR rules for plastic packaging are India's primary regulatory responses.
- 1 Microplastics = plastic particles <5 mm; primary (manufactured) or secondary (fragmented)
- 2 Sources, single-use plastic breakdown, synthetic textile washing (microfibers), tyre abrasion, cosmetic microbeads, aquaculture nets
- 3 Marine concentration, Great Pacific Garbage Patch contains 1.8 trillion plastic pieces; ~80% entered via rivers
- 4 India's rivers, Ganga, Brahmaputra identified as major plastic pathways to ocean; Sundarbans receives riverine microplastics
- 5 Impacts, ingestion by marine organisms → bioaccumulation through food chain → enters human diet; endocrine disruption suspected
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- 7 GESAMP (Group of Experts on the Scientific Aspects of Marine Environmental Protection), UN body monitoring marine microplastics
- 8 India's response, Single-use plastic ban (July 2022); EPR on plastic packaging; Plastic Waste Management Rules, 2016
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A 2025 UNESCO-supported study detected microplastic contamination in Sundarbans mangrove sediments, raising concern that plastic pollution is not only a marine debris problem but a direct threat to the Sundarbans' capacity to function as a blue carbon sink, since microplastics disrupt the sediment microbiology that enables long-term carbon storage.
