Per- and Polyfluoroalkyl Substances
Context:
Recently, The southern bench of the National Green Tribunal (NGT) have found the presence of Per- and Polyfluoroalkyl Substances (PFAs) in Chennai Waterbodies.
- PFAs are known to have adverse health effects such as liver damage, hormonal imbalance, immune system effects, and even cancer.
Relevance:
GS-03 (Conservation)
Per- and Polyfluoroalkyl Substances (PFAS):
- Per- and Polyfluoroalkyl Substances (PFAS) are synthetic chemicals utilized in the manufacturing of nonstick cookware, water-repellent clothing, stain-resistant fabrics, cosmetics, and firefighting foams, among various other products.
- Their properties make them resistant to grease, water, and oil.
- They are called Forever chemicals because of their tendency to stick around in the atmosphere, rainwater, and soil for long periods of time.
- PFAs are also listed in the Stockholm Convention.
- During production and usage, PFAS can seep into the soil, water, and air.
- These substances have a persistent nature, remaining in the environment for extended periods without breaking down. Consequently, repeated exposure to PFAS can lead to their accumulation in humans and animals.
Harmful Effects of PFAs Exposure:
- Exposure to PFAS poses numerous health risks, including decreased fertility, developmental issues in children, disruption of hormonal balance, elevated cholesterol levels, and heightened susceptibility to certain cancers.
- Recent studies indicate that prolonged, low-level exposure to specific PFAS compounds can impede the body’s ability to generate antibodies following vaccination against various diseases.
Methods for PFAs Removal:
- Incineration, though a common method for PFAS disposal, is challenged by the chemicals’ resistance to combustion.
- PFAS, characterized by strong carbon-fluorine bonds, necessitate temperatures of around 1,500 degrees Celsius (2,730 degrees Fahrenheit) for complete breakdown, making this process energy-intensive and reliant on specialized incinerators.
- Supercritical water oxidation which employees high temperatures and pressures to alter water’s state, offers a promising technique for PFAS destruction.
- Plasma reactors are currently being worked upon that utilizes water, electricity, and argon gas to degrade PFAS compounds.
- Filtration systems, incorporating activated carbon, can be integrated into rainwater harvesting systems to capture PFAS. Regular replacement of activated carbon and proper disposal of contaminated material are essential maintenance steps.
- Various experimental methods are used for PFAS treatment, although they are yet to be scaled up for large-scale applications.
