An explosion that killed 20 people last week at a chemical plant in Yizhou, in the southern Chinese province of Guangxi, poses no further threat, according to preliminary surveys by the Chinese health ministry.

The cause of the 26 August explosion is under investigation. Liu Xiongmin, an engineer specializing in disaster management at Guangxi University in Nanning, says the explosion may have been caused by a chemical leak coupled with very hot temperatures that day, which reached 36°C. The plant produced polyvinyl acetate, carbide and vinyl acetate.

The explosion destroyed the five-storey plant as well as nearby houses. Liu says that of the bulk chemicals used at the plant, ethanol was mostly burned in the explosion and methyl alcohol does not seem to have escaped in large amounts. Reportedly, none of the 60 people injured in the blast had toxic reactions.