Ecological and economic profile of the caustic-chlorine industry | Centre for Science and Environment

Ecological and economic profile of the caustic-chlorine industry

There are broadly two categories of industries. Explained simply, one makes the final product the way we see them on the shelves and one supplies the raw material or intermediate product to make the final products. The manufacturing industry depends on the intermediary industry. The manufacturing industry is at the forefront, normally facing the brunt for any environmental pollution while the intermediary industry remains obscure from the public gaze.

That is exactly why the third rating of the Green Rating Project (GRP) is significant. This time, GRP focuses on the caustic-chlorine industry of India — a key contributor to the country’s economy as well as pollution. What makes it worse is the fact that the caustic-chlorine industry has no control over the end use of the products it manufactures.

Prior to rating the caustic and chlorine sector, GRP had rated the pulp and paper sector where pollution peaked during production while for the automobile sector, pollution was maximum during the stage of product usage. The rating of the caustic-chlorine sector is unique because the issues of concern here relate to:

The output at the end of the production process – chlorine and caustic soda – that are used extensively by industries to make products like pesticides and organo-chlorine that are highly detrimental to the environment.

The utilisation, storage and transportation of the products. For example, storage of large amount of chlorine is similar to a time bomb, which if explodes, will kill all living organism within its sphere of influence.

Products of the caustic-chlorine industry


Chlorine Sodium & calcium hypo
Caustic soda Sodium bicarbonate
Hydrochloric acid Potassium hydroxide
Hydrogen Potassium carbonate

Deadly mercury pollution and contamination arising due to emissions of mercury into air, water and land. The fact that an industrial disaster that occurred 50 years ago continues to haunt the sector and has laid the basis for a totally new environmental framework indicates the potential environmental danger associated with the sector. We are referring to the infamous Minamata tragedy where mercury was dumped into the sea by a Japanese chemical company leading to its toxic contamination (see box: Liquid death).

Another issue that has considerably impacted the environmental trends of the Indian caustic-chlorine industry has been the influence of the global market on the Indian market. A situation has been created for the Indian industry, where on one hand, it has to deal with chlorine, that is neither storage nor disposal friendly and on the other hand, it has to face a glut of caustic soda in the market, because of dumping of caustic soda by China and the countries of the Gulf region.


Liquid death


Death this time travelled through the waters and found its way into homes of innocent fishing folk in a seaside town of Japan, killing children in wombs and affecting a number of people. Statistics cannot put an estimate to the suffering that spanned three decades.


The Chisso Corporation, one of the main employers of Minamata, was making petro-chemicals and plastics. From 1932 to 1968, Chisso Corporation dumped an estimated 27 tonnes of mercury compounds into Minamata Bay. The destruction of large scale fishing areas following the dumping simply saw the exchange of money to buy people off. The logic of the company was to pay people in exchange for polluting.


It was not till mid 1950s that people began to notice a strange phenomenon in animals and humans. People began to experience numbness in their limbs and lips. Their speech slurred and their vision constricted. Some people had serious brain damage. Birds started to drop dead from the skies.


The valiant effort of a doctor from Chisso Corporation itself, Dr Hosokawa