Context: A new study has revealed that microplastics (tiny plastic particles measuring less than 5mm in diameter) can block the flow of blood in the brains of mice. It is still unclear if plastics could cause similar blockages in the human brain, the analysis is concerning due to the increasing presence of microplastics in the human body.
Relevance of the Topic: Prelims: Key facts about Microplastics; their impact.
What are Microplastics?
- Microplastics are small pieces of plastic, less than 5 mm (0.2 inch) in diameter, that occur in the environment as a consequence of plastic pollution.
- Microplastics are likely to degrade into smaller nanoplastics through chemical weathering processes & mechanical breakdown.
- Nanoplastics are smaller than 1 µm (1nm - 1000 nm).
- Microplastics accumulate in the air, terrestrial ecosystems and aquatic and marine ecosystems (even found at deep layers of ocean sediment).
- Humans are exposed to microplastics by oral intake, inhalation, and skin contact. Researchers have detected the existence of microplastics in human lungs, testicles, bone marrow and even in blood.
- According to a report by the World Economic Forum, it is estimated that the average person can eat, drink or breathe between 78,000 and 211,000 microplastic particles annually.
Types of Microplastics:
Microplastics can be divided into primary and secondary microplastics.
- Primary microplastics are items of plastic that are already smaller than 5mm. E.g., nurdles (plastic beads used in plastic manufacturing), microbeads from cosmetics, fibres from clothing, spills during manufacturing or transport.
- Secondary microplastics are formed from the breakdown of larger plastics via exposure to wave action, wind abrasion, and ultraviolet radiation from sunlight.
Impacts of Microplastics
- Microplastics exposure in humans can cause:
- intestinal injury, liver infection
- neurotoxicity
- lipid accumulation and metabolic disorder
- increases expression of inflammatory factors, autoimmune disorders
- reduces the quality of germ cells, and affects embryo development
- inhalation of airborne microplastics can cause asthma, lung cancer.
- Environmental impacts:
- Causes water pollution. Bioaccumulation and biomagnification in aquatic fauna.
- In terrestrial ecosystems, microplastics reduce the viability of soil ecosystems.
- Microplastics can act as a reservoir of microbes resistant to antimicrobials.