Sulfonic acid, which can cause serious harm to human health, has leaked into the Rio Seco in Joinville, southern Brazil.

The substance – used to produce detergents and household cleaning materials – was released when a truck crashed, triggering a local state of emergency.

A treatment station was closed on Monday morning to prevent the intake of contaminated water – potentially affecting dozens of neighbourhoods’ access to drinking water.

Video on social media showed people stockpiling bottled water.