Laboratory examination of all 28 brands of soy sauce produced within Thailand are safe for consumers and do not contain dangerous levels of carcinogenic chemicals, according to the Public Health Ministry's Medical Sciences Department.

The results of the long-term research were revealed yesterday, one week after UK food agencies warned consumers away from allegedly cancer-causing soy sauce brands from Asia, and many months after the laboratory investigation in Thailand began.

Britain last week placed a ban on 21 Asian-made soy sauces, including a Thai product called Golden Mountain, but the director of the Medical Sciences Department, Dr Bhakdi Bothisiri, has stressed that extensive testing of samples has failed to show up dangerous levels of either 3-MPCD or 1,3DCP, the carcinogenic chemicals claimed to be present by UK scientists.

"These sauce samples are proved to have far less than the levels believed to be at risk of causing cancer. Therefore, we can say the products made in Thailand are safe from containing toxic chemicals," he said.

Part of the confusion, he added, is down to the accepted levels of the chemicals in food, which are different in Thailand and the UK. "The British standard level - 0.01 mg/kg - [...] is not the real international safety standard," insisted Bothisiri. In Thailand, the chemicals must not exceed the level of 0.1 mg/kg.