Cooking rice incorrectly can lead to arsenic poisoning according to scientists.
Experiments show that a common method of cooking rice can expose those who eat it to traces of arsenic poison, according to The Independent. The method in question is simply boiling the rice in a pan until the water has steamed out.
Arsenic contaminates rice while it is growing as a result of industrial toxins and pesticides. The poisonous chemical has been linked to a number of serious health problems such as heart disease, diabetes, cancer and development problems.
The BBC reports that arsenic can be particularly toxic in the form of inorganic arsenic (iAs), which is classified as a category 1 carcinogen by the European Union. The classification means it is known to cause cancer in humans.
It was generally believed that traces of arsenic are expelled when the rice is cooked. However, new experiments suggest that this can only be achieved if the rice is soaked overnight.
Professor of biological sciences at Queens University Belfast, Andy Meharg, tested three ways of cooking rice to see how the levels of arsenic changed. Meharg, who has worked in the field for decades regularly tests rice and rice products and shared his findings with the BBC programme Trust Me, I’m a Doctor. In his first test, Meharg found used a ratio of two parts water to one part rice to cook the rice. Most of the arsenic was still present after the water was steamed out.
When the professor used five parts water to one part rice and washed the excess water off, levels of arsenic were almost halved. Meharg’s third method of soaking rice overnight, arsenic levels were reduced by 80%.
Meharg’s conclusion was therefore that the safest method of cooking rice is to soak it overnight first. The rice must then be washed and rinsed until the water is clear and then draining it well before being boiled in a saucepan. The ratio should be five parts water to one part rice.
The professor also found the following:
- Basmati rice contains lower levels than other rice
- Brown rice usually contains more arsenic than white rice (because of the husk)
- Growing rice organically doesn’t make a difference to levels
- Rice cakes and crackers can contain levels higher than in cooked rice.
- The levels of arsenic found in rice milk far exceed the amounts that would be allowed in drinking water
Channel 4’s Dispatches and the Institute for Global Food Security found that around 58% of rice-based products in the UK contain high levels of arsenic. The BBC reports that rice consumption is rising in the UK, with 150 million kilograms eaten in 2015.
