Microplastics, Types, Efforts to Combat Microplastics

Table of Contents

Context: Researchers at the Indian Institute of Science (IISc) have designed a sustainable hydrogel to remove microplastics from water.

What is a Hydrogel?

Hydrogels are three-dimensional, hydrophilic polymer networks that can retain a large amount of water while maintaining structure due to their cross-linked nature.
Properties:
- They are soft and flexible, similar to natural tissue, due to their significant water content.
- Hydrogels can respond to environmental stimuli such as temperature, pH, or light, making them suitable for a variety of applications, including medical and environmental.

Features of the IISc Hydrogel

Composition: The hydrogel is composed of three different polymers: chitosan, polyvinyl alcohol, and polyaniline.
- These are intertwined to form an interpenetrating polymer network (IPN), enhancing the structural integrity and functionality of the hydrogel.
Functional Additives: Copper substitute polyoxometalate (Cu-POM) nanoclusters are infused into the polymer matrix.
- These nanoclusters act as catalysts that utilise UV light to break down contaminants, such as microplastics.
Mechanism of Action: The hydrogel functions by adsorbing microplastics onto its surface and then degrading them under UV light exposure, facilitated by the catalytic action of the Cu-POM nanoclusters.
Efficiency: In tests, the hydrogel has proven highly effective, capable of removing about 95% and 93% of two different types of microplastics found in water.
Advantages Over Conventional Methods: Unlike traditional filtration methods, which use membranes that may clog, the hydrogel does not suffer from clogging and maintains its effectiveness over time, making it more sustainable.
Sustainability Aspect: The hydrogel is designed to be reused multiple times, reducing waste and increasing its environmental friendliness.

Potential Applications

Water Treatment: Primarily used for removing microplastics from wastewater, thus preventing environmental pollution and protecting aquatic life and human health.
Scalability: The design and materials used suggest potential for scaling up for industrial applications, offering a feasible solution for large-scale water treatment facilities.

Microplastics and its Types

Microplastics are plastic particles less than 5mm in diameter.

Primary Microplastics

These are small plastic particles specifically manufactured for certain products such as cosmetics and include microfibers released from textiles like clothing and fishing nets.
Primary microplastics directly enter ecosystems through various pathways including the use of consumer products, accidental losses during industrial processes or transport, and abrasion during activities like laundering.

Secondary Microplastics

These microplastics originate from the degradation of larger plastic items, such as disposable water bottles and other plastic goods.
Secondary microplastics form when larger plastic pieces degrade due to environmental factors like wave action in oceans, wind abrasion on land, and ultraviolet radiation from sunlight leading to weathering.

Dangers of Microplastics to Humanity and Biodiversity

Environmental Persistence: Microplastics are highly persistent in the environment due to their durability and resistance to degradation.
- They can remain in ecosystems for extended periods, posing long-term risks to wildlife and habitats.
Impact on Wildlife: Microplastics are ubiquitous and can be ingested by marine organisms. They can disrupt feeding, growth, and reproduction in wildlife, affecting entire ecosystems.
- Studies have shown that microplastics can accumulate in the digestive tracts of various marine species, including fish, seabirds, and sea turtles.
Threat to Marine Life: Ingestion of microplastics can be lethal to marine organisms.
- For example, fish may mistake microplastics for prey, leading to reduced fitness and survival rates.
Health and Developmental Risks: Exposure to microplastics can result in stunted growth and behavioural changes in some species.
- These particles can interfere with normal physiological processes.
Ingestion by Marine Animals: Microplastics have been found inside the viscera of deceased sea birds, turtles, whales, and other marine reptiles.
- Their ingestion can lead to physical harm and internal damage.
Waste and Human Health Risks: Plastics that end up in landfills can leach harmful chemicals into the environment, posing direct threats to human health.
- These chemicals may include endocrine disruptors and carcinogens.
Environmental Degradation: Due to their slow degradation, plastics accumulate in ecosystems, affecting soil quality, water bodies, and habitats.
- This persistence can lead to long-term environmental presence and potential integration into food chains.
Carrier of Toxins: Microplastics can transport toxic chemical compounds, including carcinogens.
- For instance, they can adsorb and transport polycyclic aromatic hydrocarbons (PAHs) and other harmful substances.
- A recent study found that people with microplastics or nanoplastics in their blood vessels were more likely to experience heart attacks, strokes, or death.

Measures to Address the Menace of Microplastics

Local Initiatives: Effective local measures are crucial for reducing plastic pollution.
Regulatory Actions: Implementing bans on microplastics in cosmetics and providing incentives to reduce plastic use are essential steps.
International Collaboration: Countries should work together to set and achieve quantifiable plastic waste reduction targets.
Media Involvement: Media organisations should play a proactive role in educating and mobilising the public against the use of microplastics.
Civil Society Engagement: The active participation of civil society is vital in preventing the industrial use of microplastics.
Stricter Policies: Governments should enforce stringent policies with severe penalties, including heavy fines and imprisonment for violations.
Public Education: Raising awareness about the dangers of microplastics is critical for public health and environmental conservation.
Prohibition of Plastics: The most effective solution may be to ban the production and distribution of plastics altogether.
Waste Management: Promoting waste segregation can facilitate material recovery and reduce environmental impact.
Promotion of Alternatives: Encouraging and adopting eco-friendly alternatives like cloth, paper, and jute bags can significantly reduce reliance on plastics.

Efforts to Combat Microplastics

Global Actions

Global Partnership on Marine Litter (GPML): Tackles marine litter globally.
GloLitter Partnerships Project: Focuses on reducing litter from maritime activities.
London Convention (1972): Regulates dumping into the seas.

India’s Initiatives

Single-use Plastic Ban: Aims to eliminate single-use plastics.
Plastic Waste Management Rules (2016): Regulates plastic waste handling.
- Plastic Waste Management (Amendment) Rules, 2024: The 2024 amendment of the Plastic Waste Management (Amendment) Rules specifies biodegradable plastics must degrade biologically without producing microplastics.
Un-Plastic Collective: Encourages plastic waste reduction.
Kerala’s Beat Plastic Pollution Initiative: State-level effort against plastic pollution.

International Approaches to Single-use Plastic:

UN Resolution: 124 countries, including India, agreed to formulate a legally binding agreement covering the entire lifecycle of plastics to curb pollution.
Bag Bans: 68 countries enforce plastic bag bans.
Bangladesh: First to ban thin plastic bags in 2002.
China: Implemented a phased plastic bag ban in 2020.
European Union: Prohibits certain single-use plastics with available alternatives.