Chemical Disasters in India have been notorious for causing over 130 significant chemical accidents according to the National Disaster Management Authority (NDMA).  The Vizag Gas Leak will remain an important topic for [General Studies paper 2 and 3 of UPSC Mains].

Much like the infamous Bhopal Gas Tragedy of 1984, a deadly industrial chemical disaster in Visakhapatnam, Andhra Pradesh has resulted in destruction of human and animal life in Visakhapatnam in May 2020.

This Industrial disaster has occurred amid the lockdown to fight COVID-19 pandemic. Heres a roundup of what happened and the issues surrounding this Visakhapatnam Gas Leak Accident. Such Industrial Tragedies are a result of lack of systemic accountability.


What happened in Vizag gas Tragedy?

Styrene gas leaked from a storage tank located in industrial complex of LG Chem Polymers (owned by South Korean electronics giant -LG since 1997). It is located at RRV Puram, 15 km from Visakhapatnam city. Presence of this Industrial unit in a residential area was a disaster waiting to happen. Even though the unit was initially set up away from settlement, over the years the city has engulfed the industrial complex. This has also raised questions about unplanned urbanisation in Indian cities.

This Vizag industrial unit manufactures general-purpose polystyrene and high-impact polystyrene, expandable polystyrene, and engineering plastics compounds.


Why the Vizag Styrene Gas Leak Happened?

The Vizag gas leaked from its storage tank when the factory was being reopened after being shut for 44 days due to the Coronavirus lockdown. There was 1,800 tonnes of styrene stored in a tank of capacity 2,400 tonnes. About half the gas leaked before it was contained.


Storage Guidelines for storing Styrene Gas:

  1. Styrene gas has to be stored under 20°C to keep it stable.
  2. The temperature has to be continuously monitored, as any exposure to light or heat may result in polymerisation.
  3. If temperature rises, inhibitors are added to keep the styrene stable.
  4. As a safety measure, the styrene tanks are never filled to capacity.


What caused Vizag Gas Leak?

The cause for Vizag gas leak tragedy is auto polymerization (chemical reaction) and vapourisation of the styrene.

  • As the styrene was stagnant for 44 days, some gas accumulated at the ceiling of the storage tank and its temperature rose beyond the specified 20°C.
  • An inhibitor tank was attached to the styrene storage tank but it failed to stabilise it in time.
  • the Styrene started vaporising and escaped. This is called auto-polymerisation.

However, the exact cause is not yet explained, especially how the storage tank ruptured and the gas escaped.


What is Styrene?

Styrene is a volatile and a mucous membrane irritant organic gas which is used extensively in plastics and synthetic rubber industries.

Styrene is taught in Organic Chemistry in senior secondary in India. This organic compound with the formula C8H8, is used for synthesis of polystyrene (C8H8)n.

Styrene is classified as a toxic and hazardous chemical in India according to The Manufacture, Storage and Import of Hazardous Chemicals Rules, 1989.

The Styrene monomer is a flammable liquid that is used in –

  • manufacturing of polystyrene plastics packaging materials for foods and to make parts of various appliances such as refrigerators or micro-ovens; automotive parts; and parts of electronics such as computers;
  • expanded polystyrene foam, which is a ubiquitous material used for disposable coffee cups, insulated shipping containers, etc. ;
  • the production of resins such as styrene–butadiene polymer used for synthetic rubber and fiberglass.


Health effects of Styrene Exposure

Short-term exposure to styrene can result in respiratory problems, irritation in the eyes, irritation in the mucous membrane, and gastrointestinal issues.

Long-term exposure of Styrene can drastically affect the central nervous system (CNS) and lead to other neurological problems like peripheral neuropathy. It could also lead to leukemia cancer and depression in some cases.


What are the symptoms of exposure to styrene?

It affects the mucous membrane that is mainly affected by exposure to styrene gas. The symptoms of Styrene exposure are –

  • Breathlessness,
  • respiratory problems,
  • irritation in eyes,
  • indigestion,
  • nausea,
  • transient loss of consciousness,
  • unsteady gait,
  • giddiness


Legislation and guidelines on storage of hazardous chemicals in India

After the Bhopal gas tragedy 1984, much legislation was enacted. At the time of the Bhopal gas tragedy, the Indian Penal Code (IPC) was the only relevant law specifying criminal liability for such incidents. Here is a concise list of legislation framework governing the hazardous chemicals in India specifying safeguards and penalties :

  1. Bhopal Gas Leak (Processing of Claims) Act, 1985, -It  gives powers to the central government to secure the claims arising out of or connected with the Bhopal gas tragedy. Under the provisions of this Act, such claims are dealt with speedily and equitably.
  2. Environment (Protection) Act, 1986 – It gives sweeping powers to Central government to undertake measures for improving the environment and set standards and inspect industrial units.
  3. Environment (Protection) Rules, 1986 – Specify discharge and product standards for restricting pollution and for regulating quality of life and environmental protection
  4. Hazardous Waste (Management Handling and Transboundary Movement) Rules, 1989 – Specifies that industry is required to identify major accident hazards, take preventive measures and submit a report to the designated authorities
  5. Manufacture, Storage And Import Of Hazardous Chemicals Rules, 1989 – Importer must furnish complete product safety information to the competent authority and must transport imported chemicals in accordance with the amended rules.
  6. Chemical Accidents (Emergency, Planning, Preparedness and Response) Rules, 1996 – Mandates the Centre to constitute a central crisis group for management of chemical accidents; and set up quick response mechanism termed as the crisis alert system. Each state is required to set up a crisis group and report on its work.
  7. Factories Amendment Act, 1987 – Provisions to regulate siting of hazardous units; safety of workers and nearby residents and mandates for on-site emergency plans and disaster control measures
  8. National Green Tribunal, 2010 – It provides for the establishment of a National Green Tribunal for effective and expeditious disposal of cases related to environmental protection and conservation of forests.
  9. Public Liability Insurance Act, 1991 – It is an insurance meant to provide relief to persons affected by accidents that occur while handling hazardous substances. This imposes a no-fault liability on the owner of hazardous substance and requires the owner to compensate victims of accident irrespective of any neglect or default. For this, the owner is required to take out an insurance policy covering potential liability from any accident.
  10. The National Environment Appellate Authority Act, 1997 –  the National Environment Appellate Authority can hear appeals regarding the restriction of areas in which any industries, operations or processes or class of industries, operations or processes shall not be carried out or shall be carried out subject to certain safeguards under the Environment (Protection) Act, 1986.

Actions taken on Vishakhapatnam Gas Leak Accident

The National Green Tribunal (NGT)  has directed LG Polymers India to deposit an initial amount of  Rs 50 crore for the damage caused by the gas leak in Visakhapatnam. These directions came after the green panel took suo motu cognisance of the Vizag styrene gas leak incident.