BHOPAL, India — Chlorine gas leaked Monday from the Union Carbide plant where an accident four months ago killed more than 2,000 people in history's worst chemical disaster. The latest leak caused widespread panic but only minor injuries to seven people. Hundreds fled their shanty homes near the plant amid rumors that deadly methyl isocyanate gas again was leaking from the facility as it did on Dec. 3, causing widespread deaths and injury to at least 250,000 persons in the central Indian city 360 miles south of New Delhi.
Residents returned only after the Madhya Pradesh state government gave assurances that the fumes had dissipated.
Roy Choudhary, works manager of the Union Carbide plant, told reporters that chlorosulfonic acid spilled Sunday night while it was being transferred to tank trucks.
Chlorosulfonic acid is a fuming liquid that decomposes in water to sulfuric acid and hydrochloric acid and is used in pharmaceuticals, pesticides and dyes. Sulfuric and hydrochloric acids are both toxic substances.
Choudhary said when rain began falling in the morning, the liquid "reacted with water, and fumes started coming,"
Three plant operators were exposed to the fumes and were treated in the factory hospital, he said. Another four people working in the railway station behind the plant also were treated.