Vizag gas leak: What is Styrene that leaked in LG Polymers' plant?

The styrene gas is heavier than air and comes down on spraying of water, however, it remains in the atmosphere for seven to eight hours

At least 11 people died after a leak in a chemical factory in Andhra Pradesh on Thursday. The toxic gas, Styrene, injured over 1000 people after they inhaled it once it mixed in the air following the leak around 2.30 am. 

Following the leak, the area has been vacated and over 250 families have been evacuated. The National Disaster Response Force (NDRF) said that a specialized Chemical, Biological, Radiological (CBRN) team is being flown from Pune to assist the local teams in defusing the situation and that the leaking silos are at its minimum. 

What is styrene gas? 

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