Japanese rice-based drinks are becoming a central part of Western health conscious diets, such as vegan or macrobiotic diets. However, the levels of toxic inorganic arsenic contained in these types of drinks could, in fact, be cause for concern says Antonio Signes-Pastor at De Montfort University, Leicester, UK. 

High levels of arsenic have recently been found in rice-based food, explains Signes-Pastor. Now, he and his colleagues have found that drinks such as misos, syrups and amazake contain significant levels of arsenic too. 'The rice-derived products we investigated are consumed by millions of people in Japan on a regular basis, and are increasingly becoming an important part of the diet of health conscious consumers in Western countries' says Signes-Pastor. However, regularly including these types of drinks in the diet could add as much as 23 % of the daily tolerance level of arsenic, he says. 

'Although in isolation this may not seem of massive concern, for people already taking high levels of arsenic from rice and sea-weed based products this could mean exceeding maximum daily tolerance levels,' says David Polya, who researches the effects of arsenic in groundwater at the University of Manchester, UK.

Signes-Pastor explains that similar products derived from barley or millet contain much lower levels of arsenic and could be used as an alternative to the rice based drinks. This could be particularly important for people who already eat a lot of rice and sea-weed products, he adds.

Polya add that this work gives a clear implication that regulations for inorganic arsenic in foodstuffs and non-water drinks should be re-examined. He suggests 'drafting more consistent regulations for arsenic in foodstuffs and non-water drinks may lead to a reduction in the incidence of arsenic-attributable diseases, including various cancers.'

Rachel Cooper 

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