Betel quid

Study: New proof that chewing betel quid causes oral cancer

Chewing betel quid or nuts – the fourth most popular psychoactive substance in the world after tobacco, alcohol, and caffeine – exposes its 600 million users, including many in South Africa, to substances that act as direct carcinogens in the mouth, scientists are reporting in a new study.

In a new study published in the journal Chemical Research in Toxicology, Taiwanese scientists, Mu-Rong Chao and Chiung-Wen Hu, explain that betel quid (BQ) or paan consists of nuts from the arcea tree, sometimes combined with spices, such as cardamom or saffron, and other ingredients.

Available in commercial forms, BQ is popular among people in China, India, and other Asian countries, and people of Asian heritage living in the US and other countries.  BQ is typically chewed before spitting or swallowing.

According to a study in the SA Medical Journal (SAMJ), the betel nut can be chewed alone or as part of the betel package (paan or pan). The latter is a fresh mature betel leaf with the undersurface smeared with lime made up into a package which contains cuttings of the betel nut, catechu and at times tobacco. Many other innocuous condiments, sweetening and flavouring agents are sometimes added.

The bolus formed as a result of chewing is usually swallowed or can be kept in the mouth for prolonged periods of time, even during sleep. When the package contains tobacco, the bolus is spat out after chewing.

The betel vine is grown in South Africa but the nut is imported from India and it is used either raw, baked or boiled.

Scientists have known for decades that chewing BQ can lead to oral cancer, and showed recently that the substances in BQ could be changed into carcinogens in the body. The authors of this study explored whether there were any substances in the arcea nut that can cause cancer directly, without any need for the body to change or “activate” them.

They discovered that compounds in the arcea nut can “alkylate” the genetic material DNA, causing changes that increase the risk of cancer, and they are present in betel quid in amounts high enough to do so.

“Our study showed that these alkylating agents are present at levels sufficient to cause DNA damage and could potentially have adverse implications to human health, particularly in the case of the development of oral cancer for BQ chewers,” they say.

The article can be found at: Hu CW et al. (2012) Direct-Acting DNA Alkylating Agents Present in Aqueous Extracts of Areca Nut and Its Products.