This crisis began when a chemical known as MCHM, used to clean impurities from coal, leaked from a storage tank owned by a company called Freedom Industries.

这场危机的源头是一种被称为MCHM的化学物质, 这种用于清洁煤炭杂质的物质从一家名为自由工业公司的储罐中泄漏引发了这次危机。