What are microplastics?
- Microplastics are defined as synthetic solid particles sized ranging 1 micrometre (μm) to 5 millimetre (mm), which are insoluble in water.
- There are two categories of microplastics: primary and secondary.
- Primary microplastics are tiny particles designed for commercial use, such as cosmetics, as well as microfibers shed from clothing and other textiles, such as fishing nets.
- Secondary microplastics are particles that result from the breakdown of larger plastic items, such as water bottles. This breakdown is caused by exposure to environmental factors, mainly the sun’s radiation and ocean waves.
- Microplastics are recognised as a major source of marine pollution.
Microplastics in oceans and rivers
- The generation of microplastics starts from rivers.
- Major sources like untreated sewage along the river’s course, industrial waste and religious offerings wrapped in non-degradable plastics pile pollutants into the river as it flows through several densely populated cities.
- The plastic products and waste materials released or dumped in the river break down and are eventually broken down into micro particles.
- The river finally transports significantly large quantities downstream into the ocean, which is the ultimate sink of all plastics being used by humans.
- The Ganga originates as Bhagirathi from the Gangotri glaciers in the Himalayas at an elevation of about 7010m in Uttarkashi district of Uttarakhand and flows for a total length of about 2525 km up to its outfall into the Bay of Bengal through the former main course of Bhagirathi-Hooghly.
- The principal tributaries joining the river are the Yamuna, the Ramganga, the Ghaghra, the Gandak, the Burhi Gandak, the Kosi, the Mahananda and the Sone. Chambal and Betwa are also the two other important sub-tributaries.
Why in the news?
- The study, ‘Quantitative analysis of Microplastics along River Ganga’ done by Delhi-based environment NGO Toxics Link has revealed pollution by microplastics in River Ganga.
- Water samples were collected at Haridwar, Kanpur and Varanasi.
- The highest concentration of such plastic was found at Varanasi, comprising single-use and secondary plastic products.
- Results show presence of at least 40 different kinds of polymers as microplastics.
- The most frequent size range observed in all the samples was <300µm.
- Various stakeholders, including industry, the government and civil society organisations, need to join hands for improving plastic waste management and the subsequent reduction in microplastic pollution
- Improved solid and liquid waste management can deter the generation of microplastics at source.