Turmeric has long been prized in Ayurvedic medicine for its anti-inflammatory properties and in Asian cuisines for its earthy flavour and vibrant hue. But for the millions of South Asians who habitually consume it, turmeric’s skin-staining yellowness can be deceptive and deadly.
To heighten their colour, the rhizomes from which the spice is extracted are routinely dusted with lead chromate, a neurotoxin. The practice helps explain why South Asia has the highest rates of lead poisoning in the world. The heart and brain diseases it causes accounted for at least 1.4 mn deaths in the region in 2019. The economic cost is crippling; that year lead poisoning is estimated to have lowered South Asian productivity by the equivalent of 9% of GDP. Yet it turns out that with clever policies, enlightened leadership and astute messaging this blight can be greatly reduced. Bangladesh has shown how.
At the instigation of teams from Stanford University and the International Centre for Diarrhoeal Disease Research, the country launched a nationwide campaign against turmeric adulteration in 2019. Rules against adulteration were enforced and well-publicised stings carried out against wholesalers who persisted in it.
According to newly published data, the country thereby reduced the prevalence of turmeric adulteration to zero in just two years. That slashed lead levels in the blood of Bangladeshi turmeric-mill workers by about a third. Nationwide, it probably saved thousands of lives.
Other countries where lead poisoning is rife should follow Bangladesh. Recent estimates suggest a staggering 815 mn children have been poisoned by the metal. According to the Centre for Global Development, a think-tank in Washington, this disaster explains a fifth of the learning gap between children in rich and poor countries.
The poisoning has many causes. Weak or absent regulators permit lead-infused cooking utensils, cosmetics and other products. Yet adulterated turmeric looks like a major culprit almost everywhere, chiefly owing to poor practice in India, which produces 75% of the spice. India was the source of much of the poisonous pigment found in Bangladesh and is estimated to have the highest incidence of lead poisoning of any country.
Bangladesh’s response could work in many countries. Its key elements included an openness to foreign expertise; effective NGOs; a willingness by the government to work with them; and the formation of an even broader coalition, also including journalists and private firms, to maximise the effort.