Microplastic menace in Antarctica, UN to analyse penguin droppings, water (GS Paper 3, Environment)
Why in news?
- Scientists from the International Atomic Energy Agency (IAEA) and the Argentine Antarctic Institute (IAA) have embarked on an expedition to Antarctica to investigate the extent of microplastic pollution in this remote region.
Details:
- Utilizing nuclear science techniques, the team aims to analyse samples from the icy waters, seabed sediment, and even penguin droppings to gain insights into the presence and origins of these pollutants.
- This initiative is part of the IAEA's NUTEC Plastics Initiative, which has been examining microplastic pollution across various countries. The study in Antarctica is particularly significant due to the continent's crucial role in the planet's overall health.
- The investigation also seeks to determine whether the microplastics found in Antarctica have been transported by sea currents from other parts of the world or if they originate from local sources.
- This distinction is critical for developing effective measures to address the issue.
Microplastics:
- Microplastics, defined as particles smaller than 5 millimeters, have become a pervasive environmental issue, with their harmful effects extending to even the most isolated corners of the Earth.
- These tiny particles are often ingested by wildlife, leading to the accumulation of toxins within organisms and potentially causing diseases.
Why it matters?
- The presence of microplastics in Antarctica is a stark reminder of the global scale of plastic pollution. Since plastics were introduced to the market, an estimated 7 billion tons have been discarded into the environment, with a significant portion ending up in marine ecosystems.
- The findings from this study are expected to contribute to the urgent need for policies and actions to mitigate the impact of microplastics on the environment and wildlife, not only in Antarctica but globally.
Way Forward:
- As the world grapples with the challenges of pollution, this collaborative effort between the IAEA and IAA highlights the importance of international cooperation in preserving the pristine nature of Antarctica and protecting the health of our planet.
Majority of Indian cities far from clean air target, says study
(GS Paper 3, Environment)
Why in news?
- The Centre’s ambitious attempt to improve air quality in some of India’s most polluted cities suggests that a majority of Indian cities are far from making significant progress.
- In 49 cities whose particulate matter numbers were consistently available for five years, 27 showed a decline in PM 2.5 while only four had met or exceeded the targeted decline, according to an analysis by Respirer Living Sciences and Climate Trends.
National Clean Air Programme (NCAP):
- The stated goal of the ₹9,631-crore National Clean Air Programme (NCAP) is to reduce average particulate matter concentrations 40% by 2026 (compared to 2017) in 131 cities.
- When the programme was initiated, the aim was to cut pollution 20-40% by 2024 in this cities but this goalpost was later shifted to 2026.
Key Findings:
- While the deadline is still three years away, some of India’s biggest cities are reporting marginal declines or even increasing pollution loads. Delhi, for instance, has seen average, annual PM 2.5 levels decline only 5.9%. Navi Mumbai, a suburb of Mumbai, has seen a 46% rise in PM 2.5 levels.
- Among the cities that showed a sharp decline in PM 2.5 from 2019-2023 were Varanasi, with a 72% average reduction in PM 2.5 levels and 69% reduction in PM 10 levels.
Monitoring stations:
- Another factor that significantly influences annual concentrations of pollutants in a city is the number and spread of continuous ambient air quality monitors.
- While cities such as Mumbai and Delhi have several such stations spread across the breadth of the cities to account for pollution in diverse areas, most Indian cities have only a handful.
- Only four of the 92 cities part of the analysis have more than 10 such stations.
- Varanasi in 2019 had only one such station, which only worked 24% of the time whereas by 2024 it has four stations that have been operational all days. Majority of cities have less than five stations.
Way Forward:
- The National Clean Air Programme has made noteworthy progress, witnessing notable reductions in PM 2.5 and PM 10 levels in top polluted cities.
- Despite these positive strides, persistent challenges exist, with some urban areas facing an uptick in pollution concentrations.
Could sisal leaves make sanitary napkins more sustainable in India?
(GS Paper 2, Health)
Why in news?
- The ancient Aztec and Mayan civilisations were perhaps the first to begin making paper out of sisal leaves. Since then, they have been used to make twine, cloth, and carpets. The plant itself is also used to make mezcal, a distilled alcoholic beverage.
- Now, in a move to make menstrual hygiene products more environmentally sustainable, scientists at Stanford University have reported a method to produce from sisal leaves a “highly absorbent and retentive material”.
Potential:
- The material can potentially replace cotton, wood pulp, and chemical absorbents in sanitary napkins.
- The absorption capacity of the material is higher than those found in commercial menstrual pads.
- The method uses no polluting or toxic chemicals, can be carried out locally at a small scale, and is environmentally sustainable.
Access to menstrual hygiene products:
- Access to menstrual hygiene products remains limited for around 500 million people worldwide. In rural India, for example, only 42% of adolescent women use exclusively hygienic methods to manage their periods.
- One key barrier in making menstrual hygiene products, like sanitary napkins, accessible is the rising cost of raw materials and distribution.
- The absorbent material in sanitary napkins is often a combination of wood pulp and synthetic superabsorbent polymers (SAPs). The latter are materials that can absorb a large amount of fluid relative to their own mass.
Non-biodegradable waste:
- Even as State and Central governments in India are working to make sanitary napkins available widely at lower prices, experts say that their widespread use is environmentally unsustainable.
- Menstrual sanitation waste is adding non-biodegradable waste in the environment and in turn, constituting an environmental hazard.
- The single-use sanitary napkins contain dioxin, which is a persistent environmental pollutant as well as a carcinogen that puts users of sanitary napkins at risk of cancer. The International Agency for Research on Cancer (IARC) classifies dioxin as a “known human carcinogen”.
Why sisal?
- Like all succulents, which are plants with thickened parts to store more water, sisal has an uncanny ability to store water and thrive in drought-prone areas. Its leaves grow up to 2 m long.
- The lifespan of a sisal plant is about 7-10 years, during which it produces 200-250 usable leaves.
- Each leaf has about a thousand fibres that can be used to make ropes, paper, and cloth. Now, it could be used to make a highly absorbent material as well.
- Given the cultivation of sisal requires less water and is less environmentally damaging than cotton industries. There is a “25-fold difference” in water use “for cultivation and harvesting” “between cotton and sisal”.
Mechanism:
- The recently developed process begins by feeding sisal leaves into a machine. This machine is a decorticator: it mechanically separates the fibres.
- In the next step, called delignification, a polymer called lignin, found in plant cell walls that repels water, is dissolved away. What remains is highly absorbent cellulose fibre.
- Traditionally, the delignification process for converting wood to absorbent wood pulp involves treating wood chips with a harsh chemical mixture containing water, sodium hydroxide (a strong alkali), and sodium sulphide. This process, called the Kraft process, is effective but also produces volatile and toxic by-products that can cause both air and water pollution.
- For a more environmentally sustainable way to delignify sisal leaves, they found two organisms particularly adept at converting wood to wood pulp: termites and wood-rot fungi.
Way Forward:
- A robust research is required to ensure plant fibre-based menstrual hygiene products live up to existing quality standards.
- The on-field performance of such plant based fibre products is [often] not at par with existing products.
