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