Microplastics | 27 May 2024

Source: DTE

Why in News?

Recently, a study revealed the widespread occurrence of microplastics in the testicles of both humans and canines, potentially associated with decreased sperm count, with polyethene emerging as the predominant microplastic followed by PVC.

What are Microplastics?

• About:
  • They are defined as plastics less than five millimetres in diameter. It can be harmful to our ocean and aquatic life.
  • Under the influence of solar UV radiation, wind, currents, and other natural factors, plastic fragments into small particles, termed microplastics (particles smaller than 5 mm) or nanoplastics (particles smaller than 100 nm).
• Classification:
  • Primary Microplastics: They are tiny particles designed for commercial use and microfibers shed from clothing and other textiles.
    • E.g., microbeads found in personal care products, plastic pellets, and plastic fibres.
  • Secondary Microplastics: They are formed from the breakdown of larger plastics, such as water bottles.
    • Exposure to environmental factors, primarily solar radiation and ocean waves, is the cause of this breakdown.
• Applications of Microplastics:
  • Medical and Pharmaceutical Uses: Used in targeted drug delivery due to the capacity to absorb and release chemicals effectively.
  • Industrial Applications: Used in air-blasting technology for cleaning machinery and in the production of synthetic textiles.
  • Cosmetics and Personal Care Products: Used as exfoliating agents in facial scrubs, toothpaste, and other personal care products.

What are the Current Developments Regarding Microplastics?

• Microplastics in Testicular Tissues: The study reported mean total microplastic levels of 122.63 µg/g in dogs and 328.44 µg/g in humans, with polyethene (PE) being the dominant polymer. This discovery raises concerns about the potential impact on human reproductive health, including declining sperm counts.
• Global Plastic Overshoot Day (POD): In 2024, POD is projected to occur on 5th September, marking the point when plastic waste generation exceeds the world's capacity to manage it.
  • By the end of 2024, 217 countries are expected to release over 3 million tonnes of microplastics into waterways, with China and India being the top contributors.
• Microplastics in Drinking Water: A critical review assessed the quality of 50 studies on microplastics in drinking water and freshwater sources.
  • It highlighted the need for standardised sampling and analysis methods, as only four studies met all the quality criteria.
• Microplastic contamination in Ashtamudi Lake: A study highlights significant microplastic pollution in Ashtamudi Lake, a Ramsar wetland, revealing microplastics in fish, shellfish, sediment, and water.
  • Hazardous heavy metals like molybdenum, iron, and barium were found in microplastics, posing risks to aquatic organisms and humans who consume contaminated fish and shellfish.

What are the Challenges Related to Microplastics?

• Environmental Challenges:
  • Microplastics are highly persistent in the environment, and their small size allows them to be transported over long distances, making them ubiquitous pollutants.
  • Microplastics pose a threat to wildlife, especially marine organisms, as their ingestion can result in the bioaccumulation of toxic chemicals.
• Health Challenges:
  • Humans are exposed to microplastics through eating, breathing, and skin contact, which are found in tissues like the placenta and can cause health issues like oxidative stress, DNA damage, organ dysfunction, metabolic disorders, etc.
• Regulatory and Policy Challenges
  • Despite some countries banning microbeads, there's no worldwide regulation for all microplastic sources and inconsistent monitoring hampers pollution mitigation efforts.
  • Limited resources, inadequate infrastructure, and lack of public awareness impede the effective enforcement of existing regulations.
• Detection and Analysis Challenges: Detecting and quantifying microplastics in environmental samples is challenging due to their diverse properties.

Way Forward

• Scientific Research and Monitoring:
  • Developing and promoting the use of biodegradable plastics can help reduce the persistence of microplastics in the environment.
  • Filtration systems in wastewater treatment plants and devices to capture microplastics from stormwater runoff can help reduce microplastics entering aquatic environments.
    • Techniques such as Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and mass spectrometry are commonly used but need further refinement to improve accuracy and reliability.
• Regulatory Measures:
  • Implementing bans on single-use plastics and microbeads in personal care products can significantly reduce the release of primary microplastics into the environment.
    • The European Union's REACH regulation is an example of such a measure.
  • EPR schemes make producers responsible for the entire lifecycle of their products. This can incentivise manufacturers to design more sustainable products and reduce plastic waste.
• Innovative Ways to Deal with Microplastics:
  • Biodegradable Silk: Researchers at MIT have developed a silk-based system that can replace microplastics in various applications, including agricultural products, paints, and cosmetics.
  • Plant-Based Filters: The filter made of tannins and wood dust that can trap up to 99.9% of microplastics in water.
  • Natural Fiber Textiles: Natural fiber textiles do not release microplastics during washing and are biodegradable under the right conditions. These materials offer a sustainable alternative to synthetic fibers like polyester and nylon.
• Public Awareness and Education:
  • Incorporating information about microplastics and their impacts into school curricula can educate the next generation about the importance of reducing plastic pollution and adopting sustainable practices.