YOU OLD GASBAG

The gases in your body. This week: The chemical warfare gas HYDROGEN cyanide, a chemical warfare agent, has a distinctive bitter almond-like odour and can kill in minutes. But it is also produced by the body, and found in blood, urine and naturally exhaled air.

Its exact role is still unclear, but researchers at Purdue University in the U.S. say it may be involved in regulating temperature and blood pressure.

In medicine, its use has been investigated as a potential treatment for cancer, as it is thought to break down cancer cells. Taiwanese researchers tested the effects of bitter almonds (a compound of these can produce the gas) on human cancer cells, and found the more extracts used, the greater the damage to the cells.