Microplastics

What are Microplastics

Microplastics are defined as plastics with a diameter of less than five millimetres, which is smaller than the typical pearl used in jewellery. It might be detrimental to aquatic life and our oceans.

The term ‘microplastics’ was introduced in the mid-2000s.

Microplastics are solid plastic particles composed of mixtures of polymers and functional additives. They may also contain residual impurities. 

Sources of Microplastics

Microplastics (plastic particles ranging in size from 5 mm to 1 nm) and nanoplastics (plastic particles smaller than 1 nm) have been found in every ecosystem on the planet from the Antarctic tundra to tropical coral reefs.

Microplastics come in two different varieties.

• The primary microplastics are microfibers shed from garments and other fabrics and microscopic particles made for industrial usage.
  E.g. Personal care products may contain microbeads, plastic fibres, or pellets of plastic.
• When bigger plastics like water bottles break down, secondary microplastics are created. The sun's rays and ocean waves are the key environmental variables that contribute to this disintegration.

The marine environment, oxidation tanks and sewage sludge, cosmetics and make-up, clothing and synthetic materials, mobility and tyres, navigation, and fishing are the sources of microplastics.

Plastic debris (including microplastics) is found in greater abundance close to its sources, and all plastic debris tends to be found in higher quantities near population centres.

Effect of microplastics

Microplastic debris are a major global environmental issue.  MP have been detected in air, water, soil, food and beverages, indicating that exposure of humans to these particles is ubiquitous.

Researchers first reported finding tiny beads and fragments of plastic, especially polystyrene, in the ocean in the early 1970s. The physical effects of plastic debris due to both entanglement and ingestion have been clearly demonstrated. However, it has proved more difficult to demonstrate these effects for microplastics.

The ecotoxicological profiles of compounds added to plastics to achieve certain properties (e.g. durability, flexibility, UV resistance) are generally well known. What is not known with enough certainty is the degree to which these additives can be transferred from a plastic particle into an organism, and whether this takes place at a level that will result in a significant impact of chemicals on the organism.

Many plastics absorb organic contaminants, such as the pesticide DDT and polychlorinated biphenols (PCBs), to a high degree. These compounds can cause
chronic human health effects, including disruption of the hormonal system (endocrine disruption), inducing genetic changes (mutagenicity) and cancer (carcinogenicity). Once ingested by fish, birds or mammals, the compounds – which penetrate the structure of the plastic – may start to leach out. The rate and direction of transfer of persistent, bioaccumulating and toxic compounds will depend on the chemical environment in the gut and the existing levels of those compounds in the tissue.

Plastic resin pellets are industrial feedstock for plastic products. They are typically spherical or cylindrical and only a few millimetres in diameter. In addition, plastic microbeads are used in many industrial applications, including as ingredients in printer inks, spray paints, injection mouldings and abrasives.

Microplastics have also been reported to be identified in blood samples of humans in levels that were over the quantification threshold. In 50% of the samples, the researchers discovered PET particles. They discovered polystyrene in 36% of the samples, polyethylene in 23%, and poly(methyl methylacrylate) in 5%. Polypropylene was not found in any detectable amounts, though. In each donor, they discovered an average of 1.6 micrograms of plastic particles per millilitre of blood.

Initiatives to tackle Microplastics

1. Elimination of Single-Use Plastic: India has implemented the ban of single use plastics, which have low utility and high littering potential, with effect from 1st July, 2022.
2. Important Requirements: According to the 2016 Plastic Trash Management Rules, each local body is in charge of setting up the necessary infrastructure for the collection, processing, and disposal of plastic waste.
3. The Extended Producer Responsibility (EPR) idea was introduced by the Plastic Waste Management (Amendment) Rules of 2018.
4. Un-Plastic Collective: The Confederation of Indian Industry, WWF-India, and UNEP-India jointly announced the Un-Plastic Collective (UPC), a voluntary effort.
5. The Collective works to reduce the negative effects plastic pollution has on the ecological and social wellbeing of our world.
6. Global Partnership on Marine Litter (GPML): In response to a demand made in the Manila Declaration, the GMPL was established during the 2012 Earth Summit.
7. London Convention, 1972: The 1972 Convention on the Prevention of Marine Pollution by Dumping Wastes and Other Matter was signed to regulate the disposal of garbage into the ocean and to limit all sources of marine pollution. The Plastics Pacts are business-led initiatives to restructure the value chain for plastic packaging across all formats and goods.

Way Forward

• Combination of Degradation Mechanisms: For efficient and thorough disintegration of microplastics, a combination of photo and biological degradation systems has been proposed.
• International Cooperation: The worldwide problem of plastic waste necessitates the creation of a new international agreement based on the Paris Agreement and the Montreal Protocol. Exclusively if all nations and decision-making bodies decide to monitor microplastics along their individual beaches and put into practise directives to use only biodegradable plastics can the world's plastic crisis be resolved.
• Reducing Plastic Consumption: Plastic consumption can be minimised to ensure the reduction in the level of microplastic pollution. Government, business and the community must work together to considerably reduce the quantity of litter seen along beaches and in oceans.Every individual can take actions to reduce microplastic pollution on their own, such as making zero-waste travels, forgoing disposable cutlery in favour of their own, discontinuing the usage of bottled water, and giving up plastic packaging.
• Economic Support for Recycling Projects: It is possible to enforce financial support for initiatives that recycle single-use goods and turn garbage into a resource, including tax breaks, R&D money, technology incubation, and public-private partnerships.

References

1. UNEP publication on Microplastics
2. WHO publication - Dietary and inhalation exposure to nano- and microplastic particles and potential implications for human health