MICROPLASTICS IN OCEANS
1. Context
An estimated 170 trillion plastic particles weighing about 2 million metric tons are currently afloat in the oceans across the world, according to a new study, which added that if no urgent action is taken then this number could nearly triple by 2040
2. About Microplastics
- Microplastics are tiny plastic particles that result from commercial product development and the breakdown of larger plastics.
- They are fragments of any type of plastic less than 5mm(0.20 in) in length.
- Plastic pollution is big evil and can help viruses alive and infectious in fresh water for days
- Microplastics are particularly harmful to the oceans as they don’t readily break down into harmless molecules and adversely affect the health of marine organisms, which mistake plastic for food. Moreover, these particles can trigger loss of biodiversity and threaten ecosystem balance
3. Key Findings
- Fisheries in Goa primarily operate around estuaries — vital ecological zones that provide nursery habitats for juvenile fish and feeding grounds for adults. These regions are rich in finfish and shellfish, both of which are central to local fishing practices.
- Owing to their abundance, affordability, and high protein value, these species are widely used in Indian diets.
- Small pelagic species such as anchovies, sardines, and mackerel play a crucial role in estuarine food webs. They feed on plankton and, in turn, attract larger predatory fish. As filter feeders, they capture suspended particles from the water, making them more susceptible to ingesting microplastics.
- These smaller fish serve as prey for larger species, which are themselves eaten by elasmobranchs — cartilaginous fishes like sharks inhabiting shallow coastal waters. Through this process, known as trophic transfer, microplastics move progressively up the food chain, ultimately impacting apex predators and humans.
- Researchers examined fish from the Mandovi estuarine system — part of the Mandovi-Zuari complex that accounts for nearly 97% of Goa’s total fish production. The bamboo shark, a top predator, was chosen as the focal species to study the consequences of microplastic buildup.
- This study bridges a major knowledge gap by addressing five key aspects: the extent of microplastic contamination in commercially important fish, factors influencing their ingestion, primary pathways of entry within fish bodies, evidence of microplastics in bamboo sharks, and the broader implications of such contamination for marine and human health along Goa’s coastline
| They also identified four major shape-types of microplastics: fibres (53%), fragments (29.9%), films (13.1%), and beads (4%). Marine animals use colours to detect prey, and the particles came in nine hues: blue (37.6%), black (24.3%), red (12%), discoloured (8.7%), transparent (6.8%), green (4.4%), pink/purple (2.5%), yellow (1.9%), and orange (1.7%).The types and colours of microplastics revealed their sources to be fishing gear, tire residue from roads, e-waste, packaging, and textiles. |
4. Impacts of Microplastics on Ocean and Marine life
- Several recent studies have detected microplastics in marine organisms, from phytoplankton to whales and dolphins, which might prove hazardous for them
- The ingestion of such particles can cause “mechanical problems, such as lacerations and blockages to internal systems.”
- Ingested plastics can cause chemical problems by leaching absorb chemicals into organisms
- We know that microplastics absorb many hydrophobic compounds, like DDT, PCBs and other industrial chemicals, and evidence shows they can be released when ingested
- Microplastics can also disrupt the carbon cycle of the oceans
- Normally, phytoplankton absorbs carbon and are eaten by zooplankton, who excrete the carbon in the form of faecal pellets that sink to the sea floor
- Once these carbon-containing pellets reach there, “the carbon can be remineralized into rocks preventing it from escaping back into the atmosphere,”
- If zooplanktons consume microplastics, their faecal pellets sink at a much slower rate, which means they are more likely to break apart or be eaten by other animals
- Making it less likely that the carbon will reach the seafloor and become permanently sequestered
5. How to limit plastic pollution in oceans
- Researchers of the latest study suggested that there is an urgent need to implement a global resolution to limit the production of single-use, throwaway plastic
- We need cities to be responsible for managing their waste so it does not leave their territory
- We need to reduce the amount of chemical additives in new plastic products
- If we talk about recycling, there have to be requirements that recycled plastic be used in new products
- The industries that make plastic like to talk about how technically we can recycle all of it. But they don’t like to commit to buying recycled plastic, therefore recycling fails
6. Risk Assessment
- Overall, the study classified the region and its ecosystem as having a low overall risk, though it noted that benthic organisms — those living on or near the sea floor — face greater vulnerability than pelagic species that inhabit open waters. The researchers detected 19 types of plastic polymers, of which 11 were deemed highly toxic.
- The findings also revealed that 66 out of 71 shellfish species examined had poor nutritional value. Earlier research has linked microplastic exposure in fish to reduced fitness levels, lower protein and fatty acid content, and diminished nutritional quality.
- Beyond the ecological impact, these changes may have socioeconomic consequences: as the quality of such fish declines, market demand may fall, threatening the livelihoods of coastal communities dependent on fisheries.
- Given that microplastics are now present across the planet, the study emphasizes the urgent global need to tackle plastic pollution through improved waste management systems and innovation in biodegradable alternatives
7.What is the Global Plastics Treaty?
- In March 2022, the United Nations Environment Assembly (UNEA) committed to combating plastic pollution, including in marine ecosystems. To achieve this, it established Intergovernmental Negotiating Committees (INC) tasked with drafting a treaty by the end of 2024.
- Over two years, countries convened five times to reconcile differing perspectives on addressing plastic pollution. While many nations support recycling initiatives and banning specific plastics, such as India's 2022 prohibition on single-use plastics, they remain hesitant to curb overall plastic production. This resistance stems from the economic significance of plastic manufacturing in petro-states and countries with large polymer industries.
- Ahead of the most recent negotiation round in Busan, South Korea, INC-5 Chair Luis Vayas Valdivieso presented a draft "non-paper," summarizing nations' varied approaches to managing plastic production.
- However, negotiations highlighted a stark divide between countries that see plastic pollution as a waste management issue and those advocating for production cuts at the source. This gap remains unresolved
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For Prelims: Microplastics, Nano Particles, Particulate Matter, Wastewater Management
For Mains: GS III - Environment and Ecology
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Previous Year Questions
1.Consider the following statements: (UPSC CSE 2022)
1. Other than those made by humans, nanoparticles do not exist in nature.
2. Nanoparticles of some metallic oxides are used in the manufacture of some cosmetics.
3. Nanoparticles of same commercial products which enter the environment are unsafe for humans.
Which of the statements given above is/are correct?
A. 1 Only
B. 3 Only
C. 1 and 2
D. 2 and 3
Answer (D)
2.There is some concern regarding the nanoparticles of some chemical elements that are used by the industry in the manufacture of various products. Why? (UPSC CSE 2014)
1. They can accumulate in the environment, and contaminate water and soil.
2. They can enter the food chains.
3. They can trigger the production of free radicals.
Select the correct answer using the code given below.
A.1 and 2 only
B.3 only
C.1 and 3 only
D.1, 2 and 3
Answer (D)
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Source: The Hindu
