Context: Emerging scientific evidence indicates that inhalable microplastics have become a significant but under-recognised air pollutant in Indian cities, aggravating the public-health burden already posed by particulate matter (PM₂.₅ and PM₁₀). These particles are ≤10 micrometres in size, enabling them to bypass upper respiratory defences and penetrate deep into lung tissue, resulting in chronic exposure.
Why Inhalable Microplastics Are a Serious Concern in India
High Urban Exposure:
A multi-city study by IISER Kolkata found an average airborne microplastic concentration of 8.8 µg/m³, implying that an average Indian inhales around 132 µg daily. This represents a continuous toxic load comparable to other major airborne pollutants.
Seasonal Amplification:
Winter conditions significantly worsen exposure. Evening concentrations rise by 74% during winter (32.7 particles/m³ compared to 18.8 in non-winter months), aligning with India’s broader seasonal smog phenomenon driven by temperature inversion and stagnant air.
City-Level Disparities:
Megacities show alarmingly high concentrations. Delhi (14.18 µg/m³) and Kolkata (14.23 µg/m³) record some of the highest exposure levels, reflecting dense traffic, waste mismanagement, and industrial activity.
Trojan-Horse Toxicity:
Microplastics act as carriers of heavy metals (lead, cadmium) and endocrine-disrupting chemicals such as diethyl phthalates. This amplifies toxicity beyond the plastic particles themselves.
Disease Vector Risk:
Studies have identified inhalable microplastics carrying fungal spores (e.g., Aspergillus fumigatus) and antibiotic-resistance genes, increasing the risk of respiratory infections and treatment failures.
Occupational Vulnerability:
Traffic police, construction workers, and street vendors face heightened exposure, particularly from tyre-wear microplastics, which are associated with carcinogenic compounds.
Measures Taken by India to Curb Microplastic Pollution
- Single-Use Plastic Ban (2022): Prohibits identified plastic items such as straws, cutlery, thin bags, and thermocol to reduce plastic fragmentation.
- Plastic Waste Management (PWM) Rules: Enforce Extended Producer Responsibility (EPR), obligating producers to collect and recycle plastic waste.
- Microbead Prohibition: Bans plastic microbeads in cosmetics and personal-care products, eliminating a direct microplastic source.
- National Action Plan for Marine Litter: Aims to curb plastic inflow into rivers and oceans, indirectly reducing secondary microplastic formation.
About Microplastics
Microplastics are plastic particles smaller than 5 mm and are classified as:
- Primary microplastics: Intentionally manufactured small particles (e.g., cosmetic microbeads, synthetic fibres).
- Secondary microplastics: Result from degradation of larger plastic items due to UV radiation, heat, and mechanical abrasion.
Conclusion
Inhalable microplastics represent a new frontier of air pollution risk in India, intersecting environmental degradation with public health, occupational safety, and antimicrobial resistance.
Addressing this invisible pollutant requires integrating microplastics into air-quality monitoring, strengthening plastic governance, and prioritising research on long-term health impacts.