Vizag leak shows Bhopal lessons weren’t learnt

Ignoring these factors at the start, and intentionally turning a blind eye to them at the initial stage and during operation is risky. As a result, sustainable development has been endangered.

Vizag leak shows Bhopal lessons weren’t learnt

Rescuers evacuate people following a gas leak incident at an LG Polymers plant in Visakhapatnam. (Photo: AFP)

Achemical leak from the LG Polymers plant in Visakhapatnam early on 7 May killed at least 11 people, led to evacuation of about 3,000 people, forced admission of 270 people to various hospitals and triggered panic in the industrial coastal city. It was feared many others may be unconscious in their homes and the death toll could climb.

The leak was from two 5,000-tonne tanks that had lain unattended due to India’s coronavirus lockdown in place since late March and the families in the surrounding villages were asleep at the time of gas leak. This incident has proved that regulatory authorities and the government did not learn any lesson from the Bhopal gas tragedy in 1984 considered to be one of the world’s worst industrial disasters.

Around 3,500 people, mainly in shanties around the plant operated by Union Carbide, died in the days that followed and thousands more in the following years. People continue to suffer its after-effects to this day. The recent incident in Visakhapatnam has been widely criticised and reminds us of the necessity of strong enforcement of process safety management (PSM) systems in a real sense.


This type of incident is often attributable to the unsafe state of machinery, equipment, lack of proper maintenance of storage tank, dangerous behaviour of the operators, and the lack of a thorough safety management practice. According to preliminary reports, the chemical that caused the deaths and illness was styrene.

The factory was not in operation as it was under lockdown This accident took place when the factory was being prepared for re-opening. The workers were preparing to restart operations when the gas started to leak in the early hours. LG Polymers has informed that there was 1,800 tonnes of styrene in the storage tank. According to the statement issued by the company, styrene could have resulted in auto polymerization which could have caused vaporization due to stagnation and changes in temperature.

This statement reflects the company’s casual approach despite knowing that polymerization reactions have caused a number of serious incidents in the past. Styrene is one of the most widely used monomers and has a variety of applications in the chemical industry – to produce polystyrene, acrylonitrile– butadiene–styrene rubber, and many other polymers.

However, the storage and polymerization processes are prone to runaways as monomers are thermally unstable. Researchers have reported that 48 per cent of total runaway incidents that occurred over the period from 1962 to 1987 in the UK were polymerization reactions. A reactive chemical incidents report published by the Chemical Safety Board (CSB) noted that almost 15 per cent of incidents involving uncontrolled chemical reactions in the period from 1980 to 2001 in the US were polymerization thermal runaways.

An incident statistical study showed that 17 out of 132 (13 per cent) reactive chemical incidents recorded by the major accident reporting system in the European Commission were caused by polymerization runaway reactions. More recently, 319 major industrial incidents with significant consequences based on the United Nations Environment Program (UNEP) criterion were studied and it was found that 34 of them (11 per cent) during the years from 1917 to 2011 were related to the reactive monomer/polymer process.

Also there were 30 runaway incidents in a specific unit process between 1988 and 2013 and over 33 per cent of these were polymerization incidents. A significant number of these incidents were related to styrene production and handling. Despite this, lessons have not been learned and styrene-related incidents continue. The officers in the health and safety department as well the owners of the company would well know that styrene itself is toxic.

According to the United States Environmental Protection Agency (EPA), short-term exposure to low levels of styrene in humans can cause irritation in the mucous membrane and eye, and gastrointestinal effects. Long-term exposure, on the other hand, results in effects on the central nervous system, leading to headaches, fatigue, weakness, hearing loss, nerve damage and depression. This chemical can cause loss of consciousness and death at high exposure levels. Even low levels of chronic exposure to styrene may be carcinogenic.

Without thorough investigation and analysis of the accident, real cause can not be evaluated. A question may be raised whether death of these people was due to exposure to styrene or mixing of other chemicals with styrene or typical atmospheric behavior of the chemical at the time of leak. Several factors contribute to the highly hazardous styrene handling and polystyrene production process. First of all, the styrene polymerization reaction is relatively highly exothermic with a heat generation at around 71 kJ·mol–1.

At the same time, even without an initiator, two styrene molecules will undergo a Diels–Alder type of reaction and generate radicals to start self-polymerization upon heating. This polymerization process auto-accelerates as the reaction progresses; the system viscosity dramatically increases and the reaction becomes diffusion-controlled. With reference to the accidents that happened in many industries all over the world, it may be mentioned that regulatory authorities must have been responsible as stringent measures were not taken while industry was in operation.

While granting a license to the owner of an industry handling hazardous chemicals for production of materials, the sound and fool-proof plan-do-check-act (PDCA) management model must be in place to forestall accidents, and it must be used to improve the proposal and develop counter measures that would increase PSM performance and substantially lessen the impact of the thermal hazard. This incident clearly exposed the negligence in establishing effective solutions for safety problems.

The public health and safety as well the environment are major components of sustainable development. This incident clearly exposed that public health and safety management systems were not devised to protect people through scientific assessments. On the contrary, enforcement of safety management system was outweighed by economic and political concerns. The procedure and processes being adopted to prepare PDCA management model for clearance from health and safety department and from environment department has already eroded the trust of common people in regulatory agencies leading to loss of democratic accountability.

In India, numerous procedural and bureaucratic challenges, as well as powerful political leaders exert pressure to reform the mode of clearance to establish and operate through streamlining and simplifying licensing processes. Thereby there is little scope to address corruption, larger territorial transformations, and human rights violations.

Despite stipulating standards and strong guidelines to protect public health and safety as well environment, enforcement is poor, corruption is rampant, and the justice system is slow. But corruption or manipulation in licensing processes and in regular inspection for verifying the practice of safety management system is tricky and difficult to prove because it is a practice inherently subtle though its existence seems certain.

The manipulation depends on the interests at stake, and political or lobby pressures. Therefore, the owners of the industry do not feel any need to monitor the actual status of practicing overall management systems for the safeguard of society. But I believe critical appraisal will clearly reveal the flaws in the management system that caused this accident. As per the law, industry must fulfill the requirement in accordance with the rules and regulations stipulated by the concerned authority to address legal, technical, environmental and social issues, including social welfare, compensation, safeguards and corrective measures.

But these are toothless in practice. In the name of development, regulatory agencies with political support demonstrate economic growth and employment benefit for operating industry but many risks remain in play. Ignoring these factors at the start, and intentionally turning a blind eye to them at the initial stage and during operation is risky. As a result, sustainable development has been endangered.

If such brutal killing of people continues on account of poor governance, people will be frustrated with the impassivity of authorities and will turn violent. Considering the incidents that have already taken place in India, regulatory authorities must think in new ways about project licensing processes and modes of inspection. This could lead to decisions that avoid killing of people, environmental harm, human rights violations, and costly work stoppages.

(The writer is former Senior Scientist, Central Pollution Control Board)