On 7th May 2020, Styrene gas was leaked from a chemical factory on the outskirts of Visakhapatnam.
- The Styrene gas is leaked at the LG Polymers chemical factory in Visakhapatnam.
- The Styrene plant is owned by South Korean electronics giants LG and located at RRV Puram near Gopalapatnam which is 15 Km from Visakhapatnam.
- By exposure to gas, 11 died and hundreds are hospitalized.
- Styrene is a derivative of Benzene (C6H6) and is an organic compound with the formula C8H8.
- In factories, it is stored in the liquid form as it evaporates easily. So, it has to be kept at temperatures under 20°C.
- For the synthesis of polystyrene, styrene acts as the main raw material.
- Polystyrene is a versatile plastic and is used in making parts of refrigerators, micro-oven, automotive parts, parts of computers, manufacturing disposal cups and food packaging.
- To produce copolymers, styrene is used as an intermediate.
Exposure to Styrene Gas
- Exposure to styrene will lead to breathlessness, respiratory problems, irritation in eyes, indigestion, nausea, transient loss of consciousness, unsteady gait, and giddiness.
- Exposure to styrene gas may also affect the central nervous system.
- The gas leakage in Vizag is exposed for a short duration and may not be any long-term effects.
- People suffering from a respiratory illness like asthma or chronic obstructive pulmonary diseases the conditions may worsen. Diabetic or hypertension patients may suffer from anxiety disorders.
- The mucous membrane is mainly affected by styrene gas.
- In Vishakhapatnam, the gas leak caused acute breathlessness among many people. Experts say that if people are exposed to a long period, there is a chance of developing leukaemia and headaches.
- As per the United States Environmental Protection Agency, tests involving exposure of rats and mice have shown styrene to have low moderate by inhalation and oral exposure.
- Animal studies show the effect on the central nervous system, liver, kidney, eye and nasal irritation. Liver, blood, kidney and stomach effects in animals following chronic oral exposure.
- LG Polymers, a chemical factory was established in 1961. It was named originally as Hindustan Polymers to manufacture polystyrene.
- The factory was merged with McDowell & Co of the UB group in 1978. Then it is taken over by South Korean based L G Chem in 1997 and renamed it as LG polymers.
- The factory manufactures general-purpose, high-impact and expandable polystyrene and also some engineering plastic compounds.
Vizag Gas Leak
- To keep the styrene stable, the chemical has to be stored in gas tanks at 20°C. The temperature has to be monitored constantly and exposure to light or heat may result in polymerization.
- Throughout the lockdown period, 15 engineers and officials remained on duty at the factory.
- The factory had an inhibitor attached to the styrene storage tank. The inhibitors are used to keep styrene stable if the temperatures rise.
- As a safety measure, the tanks are never filled to capacity.
- An official of the company said that 1800 tons of gas were stored in the tank of capacity 2400 tones. As the gas was stagnant for 44 days, it was possible that gas accumulated at the ceiling of the tank and temperature might have rose beyond 20°C and styrene started vaporizing and escaped. This process is called as auto-polymerization.