Context:
Groundwater contamination due to arsenic, fluoride are not addressed effectively by Central Ground Water Authority (CGWA)
Arsenic:
- Highly toxic element
- Present in – Earth crust and groundwater
- WHO’s provisional guideline value –
- Drinking water – 0.01 mg/l (10 μg/l)
- Permissible limit (in India in absence of an alternative source) – 0.05 mg/l (50 μg/l)
- Sources of exposure –
- Emitted into the atmosphere by high-temperature processes such as coal-fired power plants, burning vegetation and volcanism
- In water – Particularly groundwater from sulfide mineral deposits and sedimentary deposits deriving from volcanic rocks
- Concerns – Long-term exposure from drinking-water and food can cause cancer, skin disease, cardiovascular disease and diabetes
Fluoride:
- Present in – Soil, water, plants, and foods contain trace amounts
- Highly toxic – Death may result from ingesting as little as 2 g of fluoride in an adult and 16 mg/kg in children
- According to WHO 1984 and Indian standard drinking water specification 1991 –
- Maximum permissible limit of fluoride in drinking water – 1.5 ppm
- Highest desirable limit – 1.0 ppm
- Sources of exposure – Fluoridated water, foods and beverages prepared with fluoridated water, toothpaste and other dental products containing fluoride
- Concerns – Prolonged fluoride consumption in higher concentrations in drinking water can cause dental fluorosis, skeletal fluorosis, kidney diseases and arthritis
- Measures – Fluoride Remediation Using Biochars
Fluoride Remediation Using Biochars:
- Renewable biochar produced from rice husk biomass has the potential to absorb fluoride pollutants from groundwater
- Showed significant removal at neutral pH
- Biochar-mediated sand columns can be used for defluoridation in hand pumps and tube wells.
Read more about: Ground Water Resource Assessment Report 2023, Groundwater Management, Central Ground Water Authority
Source: Down to Earth
Previous Year Question
Which of the following are the reasons/factors for exposure to benzene pollution?
1. Automobile exhaust
2. Tobacco smoke
3. Wood burning
4. Using varnished wooden furniture
5. Using products made of polyurethane
Select the correct answer using the code given below:
[UPSC Civil Services Exam – 2020 Prelims]
(a) 1, 2 and 3 only
(b) 2 and 4 only
(c) 1, 3 and 4 only
(d) 1, 2, 3, 4 and 5
Answer: (d)
