Anheuser-Busch has insisted its beer is safe to drink after the Chinese government cut off water to the Chinese city of Harbin due to toxic contamination from an industrial accident.

An accident at a petrochemical plant in the northern city of Harbin has led to severe pollution of the Songhua river. China's state environmental protection administration said that water in some parts of the Songhua river had recorded benzene contamination more than 100 times above safety levels after explosions at two chemical sites.

The Chinese government cut off water to 3.8m of the city's 9m residents for four days starting from midnight on Tuesday (22 November).

Anheuser-Busch, which owns two breweries in the region, said the shutdown had "not significantly affected" its beer production in Harbin.

"Our Harbin brewery is currently using 100% well water in its brewing process (and) the Songjiang brewery uses 100% well water and is unaffected," Alex Chiu, vice-president of Harbin's operations, told just-drinks.

"These breweries use pure well water from underground aquifers that run deep into the earth.  Because of this, and ongoing testing procedures to ensure the high quality of our ingredients and final product, we can reassure consumers that our beers are fine and safe to enjoy."