Joss sticks smoke linked to cancer risk

Joss-stick smoke contains benzene, 1,3-butadiene and benzo(a)pyrene, which is better-known as PAH, said Dr Manoon Leechawengwong of the Chulabhorn Research Institute.

A recent study of three famous temples in Ayutthaya, Chachoengsao and Samut Prakan found their air had high levels of these cancer-causing substances, he said during a ceremony at the Rama IX Temple. At the temple, 500 leaflets and 40 signs were distributed to campaign for people to blow out their joss sticks after praying.

The study compared blood and urine samples from 40 temple workers with samples taken from 25 people living in a joss stick fume-free environment.

The temple workers were found with traces of damaged DNA and 8-hydroxydeoxyguanosine (8-OHdG) in white blood cells, which could pose a risk of genetic code change and cancer, double that of the other group, he said.

The ability of the temple workers' bodies to repair damaged DNA was also less than that of the other group.

Each year, people around the world light up joss sticks weighing tens of thousands of tonnes, he said.

One tonne of burning joss sticks would emit 325.1 kilograms of carbon dioxide and 7.2kg of methane, he said.

Dr Panuwat Panket, chief of the Non-Communicable Diseases Bureau, urged people to use shorter joss sticks or electric ones, or put the stick outdoors and stub it out after praying.