Microplastics Pollution Threatens Goa’s Fisheries and Human Health

Why in the News ?

• A new study by scientists from the CSIR–National Institute of Oceanography (Goa) and the Academy of Scientific and Innovative Research (Ghaziabad) has traced microplastic contamination in fish species along the Goan coast, particularly in the Mandovi estuarine system.
• The findings reveal bioaccumulation of microplastics in commercially important fish species, posing threats to marine biodiversity, human health, and coastal livelihoods.
  

Background

• Microplastics are plastic particles smaller than 5 mm, originating from the breakdown of fishing gear, packaging, e-waste, tyre residue, and textiles.
• These particles enter marine and estuarine ecosystems through wastewater discharge, runoff, and fishing activities.
• Goa’s estuaries, especially the Mandovi-Zuari system, which contributes 97% of the State’s fish output, serve as nurseries and feeding zones for diverse fish species.
• The study, published in Environmental Research (August 2025), examined 251 fish of nine species of finfish and shellfish captured from various depths.

Feature

Study Overview

• A total of 4,871 polluting particles were identified; 3,369 (≈69%) were plastic polymers of 19 different types.
• Benthic habitats (sea floor sediments) showed higher contamination than pelagic (open water) zones.
• Main sources: degraded fishing materials and wastewater discharge from human settlements.

Species Studied

• Included mackerel, sardine, anchovy, oyster, clam, catfish, sole fish, bamboo shark, and green mussels.
• Anchovies had the highest microplastic concentration among pelagic fish (8.8 MP/individual).
• Catfish led among benthic species (>10 MP/individual).
  Bamboo sharks, apex predators, had the lowest (3.5 MP/individual).

Pathways and Bioaccumulation

• Filter feeders and planktivores (anchovies, sardines) ingest microplastics directly from water.
• These move up the food chain via trophic transfer, accumulating in larger predators – a process termed bioaccumulation.
• More microplastics are found in digestive tracts than in gills, suggesting ingestion via prey or water.
• Fish living closer to contaminated sediments ingest more particles.
• Interestingly, longer-bodied fish accumulated fewer microplastics
  

Shape, Colour, and Type

• Shape: Fibres (53%), Fragments (29.9%), Films (13.1%), Beads (4%).
• Colours: Blue (37.6%), Black (24.3%), Red (12%), others — linked to fishing gear, tyres, e-waste, packaging.
• 11 of 19 polymer types identified were highly toxic.
  

Biological & Human Health Impacts

• Fish exhibited disrupted gene expression, oxidative stress, reproductive damage, and reduced growth.
• Shellfish (e.g., clams and oysters): 66 of 71 showed poor nutritional quality.
• For humans, potential risks include immune dysfunction, cancer risk, neurotoxicity, and hormonal disruption.
  

Challenge

Ecological Impact:

• Declining nutritional quality and survival rates of fish threaten biodiversity and fisheries sustainability.
• Estuarine ecosystems, vital for juvenile fish, are turning into pollution hotspots.

Economic Impact:

• Reduced market value of contaminated fish may hurt coastal livelihoods dependent on fisheries.

Health and Regulatory Gap:

• No national standard for permissible levels of microplastics in seafood.
  Limited monitoring infrastructure for coastal water and sediment pollution.

Scientific Gaps:

• Lack of long-term datasets on microplastic flux in Indian estuaries.
  Inadequate awareness and waste management systems along fishing harbours.
  

Way forward

Policy & Regulation

• Establish a National Microplastics Monitoring Framework under the Ministry of Environment, Forest and Climate Change (MoEFCC).
• Integrate marine litter indicators into Coastal Regulation Zone (CRZ) and Blue Economy policies.

Waste Management

• Strengthen fishing gear recycling systems and enforce Extended Producer Responsibility (EPR) for marine plastics.
• Improve urban wastewater treatment to prevent plastic inflow into estuaries.
  Research & Innovation
• Support CSIR, ICAR, and NCPOR for standardised microplastic surveillance in Indian waters.
• Promote biodegradable fishing nets and textiles.

Community Participation

• Involve local fisherfolk in citizen science programmes for beach and estuary cleanup drives.
• Create awareness campaigns about microplastic ingestion risks.
  International Collaboration
• Align national efforts with the UNEP Global Partnership on Marine Litter and the G20 Osaka Blue Ocean Vision to curb marine plastics.
  

Conclusion

The Goa study reveals how microplastic pollution has silently invaded marine food webs, posing multidimensional threats to ecology, economy, and human health.
While the contamination levels are currently categorised as low-risk, the findings are a warning bell for India’s coastal policy framework — underscoring the urgency to phase out single-use plastics, invest in scientific monitoring, and restore estuarine resilience before the damage becomes irreversible.

MAINS PRACTICE QUESTION:

Question: The presence of microplastics in India’s coastal ecosystems poses emerging risks for marine biodiversity, food security, and public health. Discuss the findings of the recent Goa study on microplastics in estuarine fisheries and suggest policy measures to address microplastic pollution in India.