By contrast, when the he used five parts water to one part rice and washed the excess water off, levels of arsenic were almost halved, while in the third method, in which the rice was soaked overnight,  levels of the toxin were reduced by 80 per cent.

The safest method of cooking rice is therefore to soak it overnight, then wash and rinse it until the water is clear, before draining it well and boiling in a saucepan, with a ratio of five parts water to one part rice.

According to 2014 research from Channel 4’s Dispatches and the Institute for Global Food Security, around 58 per cent of rice-based products in the UK contained high levels of arsenic. However, new legal limits were introduced last year by the EU in response to safety concerns