Microplastics in Goa tap water samples: Study

Context 

• A recent study has found Microplastics in samples of tap water supplied to Goa households.
• The study was carried out by CSIR-National Institute of Oceanography and Delhi-based research and advocacy organisation Toxics Link.

Major Findings 

• Microplastics were detected in all tap water samples as well as water samples collected from different Water Treatment Plants (WTPs). 
• Plastic pipes in drinking water distribution systems may be an important source of microplastics.

• The water treatment process may reduce a portion of the microplastics, some microplastics still remain in tap water. 
• However, although there is no documented evidence to date that ingesting microplastics can directly harm human health, however, the potential threat of microplastics cannot be ignored.

Microplastics

• They are plastics that are less than 5 millimetres in size but are a major source of marine pollution. 
• It is non-degradable plastics that often entered the Ganga through industrial waste or packaging of religious offerings.
• They are insoluble in water.

Impacts

• Polluting water channels: Rivers, water pipelines are being toxicated by the presence of microplastics in them. This water is used for cooking, drinking, washing etc.
• Agriculture: Same river water is used for irrigation allowing these particles to enter crops and food.
  • Microplastics in river water can cause toxicity through various means. 
    • They also have a tendency to absorb various toxins present in water, including harmful chemicals.

• Alteration of the food chain: Once these substances reach the sea, they’re ingested by fauna (especially plankton, invertebrates, fish, seagulls, sharks, whales and dolphins) and can alter the food chain. 
  • According to the environmental research institution ISPRA, 15 to 20 per cent of marine species that end up on our tables contain microplastics.
  • According to researchers from the National University of Ireland, who fished mesopelagic species that live from 200 to 1000 metres deep in the North Sea, this concentration reaches 73 per cent.

• Genetic modification diseases in humans: The pollutants released by microplastics can be ingested and absorbed by humans. 
  • These can interfere with the human endocrine system and produce genetic modifications.

Sources of Microplastics

• Global plastic production:  It went from 1.5 million tonnes to more than 280 million tonnes from the 1930s to the first decade of the 2000s (with a 38 per cent growth in the last ten years).
  • The consequences are obvious: as more plastic is used, more is thrown into the sea, directly or indirectly.

• Marine Environment: Various shapes and forms of plastic are present in marine environments: bags, microbeads, packaging, construction coating, polystyrene containers, tape and fishing equipment. 
• Oxidation tank and sewage sludge: Water depuration systems can trap plastic and fragments of various sizes through oxidation tanks or sewage sludge
  • Nevertheless, a large portion of microplastics manages to pass through this filtration system and reach seas & oceans after being thrown into rivers.

• Cosmetics and make-up: During the 1990s, cosmetics and make-up manufacturers started to use “microbeads” in skin detergents, toothpaste and shaving foams. 
  • In the second half of the 2000s, investigations have found these plastic microspheres in public water systems and in nature, ultimately ending up in the water that runs from our taps.

• Clothes and synthetic materials:
  • The fibres in synthetic materials contain large amounts of microplastics that then end up in wastewater and aquatic environments. 

• Mobility and tyres: The external part of a tyre is made from synthetic polymers mixed with rubber and other additives. 
  • According to research carried out by the IUCN, a large number of microplastics are created by the friction of tyres on asphalt. 
  • The plastic fibres released are then carried into marine environments by wind or rain. 
  • The research also explains that road signs (made with thermoplastic)release small particles under certain weather conditions.

• Navigation and fishing: Ships still cause very large amounts of marine waste: 
  • Even though an international agreement that forbids fishing boats from abandoned fishing nets and plastic entered into force in 1988, the amount of plastic left at sea was around 6.5 million tonnes at the start of the 1990s.

Challenges/Issues

• Lack of proper definition:  The lack of a solid definition of what can be considered microplastic makes it difficult to compare the results obtained in different investigations
• Lack of Technology: Lack of technology that effectively retains this kind of material at wastewater facilities is need of the hour
• Lacking exhaustive data: With greater research and data, water-management experts can set thresholds for microplastics in water, beyond which it would be considered unsafe for drinking or use in agriculture.

Initiatives on Microplastics Pollution

• India and Norway have pledged to work together to address the issue of marine plastic litter and microplastics. 
• More than 20 States and Union Territories have joined the fight to beat plastic pollution, announcing a ban on single-use plastics such as carry bags etc.
• Global efforts like “Beat Plastic Pollution” to address plastic pollution. 

Way Ahead

• Development of standard methods: Standard methods for measuring microplastic particles, including nano plastics in water should be developed to improve the quality of studies and enable researchers to compare and reproduce results. 
• Improved understanding of sources of microplastics into freshwater: Although surface run-off and wastewater effluent are considered the main sources of microplastics into freshwater, better data are required to quantify their contributions relative to other inputs and identify the original sources of contamination through these pathways. 
  • This may require establishing reliable methods to track origins and identify major sources of microplastics in freshwater. 
• Understanding of overall microplastic exposures in the environment: A better understanding of occurrence in these environmental compartments,  including the quality of these studies, will be useful in articulating relative exposure through drinking water compared to other sources.
• Segregation of the wastes at source: More focus on single-use plastics into usable recycled products using low-cost technology.
• Responsibility of manufacturers: There should be a way for the manufacturer/seller responsibility to recycle the used plastic products from the consumers through incentives/caution money deposit schemes through a public participatory approach.
• National Marine Litter policy: A policy needs to be framed to control and manage the litter at the land boundary as it is impossible to remove the litter once it enters the marine environment.

Source: IE