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.
