• UGI USER
  • Aug 17, 2023
  • 24 Likes
  • 0 Comments

Q. Arsenic pollution is becoming a severe environmental issue in India. Enumerating its various sources, discuss the consequences and measures to tackle it.

Approach:

  • Highlight the magnitude of the issue of arsenic pollution in India.
  • Enumerate the sources of arsenic contamination and discuss its consequences.
  • List the methods to tackle arsenic pollution.
  • Conclude accordingly.

Answer:

Central Ground Water Board in a recent report highlighted that 21 states have pockets with arsenic levels higher than the Bureau of Indian Standards’ (BIS) stipulated permissible limit of 0.01 milligram per litre (mg/l) and states along the Ganga-Brahmaputra-Meghna (GBM) river basin such as UP, Bihar, Jharkhand, West Bengal and Assam are the worst affected.

Further, despite arsenic contaminating the food chain, mitigation measures are targeted towards groundwater or surface water. Also, arsenic contamination testing has been restricted to drinking water sources excluding water sources used for irrigation.

Arsenic is introduced into soil and groundwater through various sources, such as:

  • During natural processes like weathering of rocks and minerals followed by subsequent leaching and runoff. It is also widely distributed throughout the air, water and land and is highly toxic in its inorganic form.
  • From anthropogenic activities like intense exploitation of groundwater, application of fertilizers, burning of coal and leaching of metals from coal-ash tailings. It is also used as an alloying agent and in the processing of glass, pigments, textiles, paper etc.

 Arsenic contamination has far-reaching consequences including:

  • Drinking arsenic water results in cancer of skin, bladder, kidney and lung, diseases of the blood vessels and reproductive disorders.
  • Intense groundwater irrigation leads to uptake of Arsenic by the crops causing photo- accumulation of arsenic in them. Thus, Arsenic enters the food chain. For example, paddy farms are exposed to Arsenic pollution. Also, when leaves are sprayed with such water, it may lead to bio-accumulation.
  • The entry of arsenic into the food chain, in addition to drinking water increases possibilities of biomagnification.
  • Rice husk used as fodder for livestock exposes them to impacts of arsenic contamination. This leads to potential risk for humans when they consume cattle-based food products.
  • The presence of arsenic in food crops means that spread of arsenic is much wider and beyond the areas where they are grown such as the GBM river basin.

The measures to combat arsenic poisoning are:

  • Treatment technologies based on lime softening and iron co-precipitation are deemed to be effective to tackle arsenic contamination.
  • Innovative technologies, such as permeable reactive barriers, phytoremediation, biological treatment and electro kinetic treatment can also be used to treat contaminated water and soil.
  • Rainwater harvesting and recharging of groundwater table should be diligently practiced to avoid fall in groundwater level and check leaching of metals into groundwater.
  • Substitution of high-arsenic sources, such as groundwater, with low-arsenic safe sources such as rainwater and treated surface water.

The extent and severity of arsenic contamination should be recognized and necessary steps should be taken to combat it. Further, the government should develop a national plan of action and ensure that mitigation measures are implemented in a coordinated manner. It should also work with academic and research institutions to improve the understanding of the causes, extent and impact of arsenic contamination.