Explainer | Methanol poisoning, its symptoms and why it is so deadly

Alcohol tainted with methanol is suspected to be the cause of death of six foreign tourists at the popular backpacker destination of Vang Vieng in Laos.

Methanol is a toxic alcohol used in industrial and household products like antifreeze, photocopier fluids, de-icers, paint thinner, varnish, and windscreen wiper fluid.

Colourless, flammable, and with a similar smell, it can be easily confused with its molecular cousin ethanol, which is usually found in alcoholic drinks.

But methanol is toxic to humans, with exposure or ingestion being extremely dangerous if left untreated.

Drinking just 25-90 millilitres (0.85 to 3 fl oz) of it can be lethal, according to the Methanol Institute, a global trade association for the industry.