GS paper III

News excerpt

The government reports widespread arsenic and fluoride in groundwater, highlighting geogenic nature; no conclusive evidence of increase.

More details about the news

• Arsenic found in 25 states, fluoride in 27 states, impacting 230 and 469 districts, respectively.
• The Central Ground Water Board (CGWB) under the Ministry of Jal Shakti conducts regular monitoring and assessment of groundwater quality including groundwater contamination of Arsenic and Fluoride.
• These studies indicate the occurrence of arsenic and fluoride in ground water beyond permissible limits -- set by the Bureau of Indian Standards - for human consumption in isolated pockets in various states and Union Territories.
• Recently, the CGWB signed a Memorandum of Understanding with the Geological Survey of India (GSI) for study of groundwater contamination, including arsenic and fluoride, with the focus on eight states
• However, the studies conducted indicate the occurrence of arsenic and fluoride contaminations in various parts of the country which are mostly geogenic in nature (from natural source).
• It means these constituents are already in the rock or soil matrix and get into the ground water through various chemical processes.

 Arsenic

• Arsenic is a naturally occurring substance that can be found in air, water, and soil. It can also be released into the environment by certain agricultural and industrial processes, such as mining and metal smelting.
• Arsenic comes in two forms (organic and inorganic); the inorganic form is more toxic than the organic form.
• Prolonged ingestion of arsenic-containing drinking water is associated with an increased risk of bladder cancer and skin cancer, and medical exposure to arsenic has been clearly associated with skin cancer in epidemiological studies.
• In addition, cancers of the lung, digestive tract, liver, kidney, and lymphatic and hematopoietic systems have been linked to arsenic exposure.
• In India, the states of West Bengal, Jharkhand, Bihar, Uttar Pradesh, Assam, Manipur and Chhattisgarh are reported to be most affected by arsenic contamination of groundwater above the permissible level.

Fluoride

• Fluoride is found naturally in soil, water, and foods.
• Excessive fluoride intake usually occurs through the consumption of groundwater naturally rich in fluoride, particularly in warm climates where water consumption is greater, or where high-fluoride water is used in food preparation or irrigation of crops.
• Such exposure may lead to dental fluorosis or crippling skeletal fluorosis, which is associated with osteosclerosis, calcification of tendons and ligaments, and bone deformities.

Prelims PYQ

Q. Which of the following can be found as pollutants in the drinking water in some parts of India? (UPSC 2013)

1). Arsenic

2). Sorbitol

3). Fluoride

4). Formaldehyde

5). Uranium

Select the correct answer using the codes given below.

(a) 1 and 3 only

(b) 2, 4 and 5 only

(c) 1, 3 and 5 only

(d) 1, 2, 3, 4 and 5