What is methanol? How does it get into drinks and cause harm?

Two Australian teenagers are severely ill in hospital in Thailand after experiencing suspected methanol poisoning while they were travelling in Laos. The pair are reportedly among several foreign nationals to become ill after unknowingly consuming alcoholic drinks containing methanol in the south-east Asian country. So what is methanol, and how does it make people sick? Methanol versus ethanol Methanol is an alcohol , like the familiar ethanol we consume in alcoholic beverages.

Like ethanol, methanol is a colourless, flammable liquid. It has a smell similar to ethanol as well. But the two have different chemical structures.

Methanol is composed of only one carbon atom, while ethanol has two. That one carbon atom makes all the difference. It means methanol is processed differently in our bodies and is much more toxic than ethanol.

Methanol is used in a variety of industrial and household products , such as windshield cleaning fluids, antifreeze and fuel. It’s not safe for human consumption. What makes methanol toxic? The difference is in how methanol is metabolised, or broken down in our bodies.

Ethanol is metabolised into a chemical compound called acetaldehyde. Acetaldehyde is toxic, but is rapidly converted to acetate (also known as acetic acid, found in vinegar). Generating an acid may sound bad, but acetate actually produces energy and makes important molecules in the body.

By contrast, methanol is metabolised into formaldehyde (a chemical used in industrial glues and f.