A new study reveals that lead levels in turmeric sold in India, Nepal, and Pakistan exceed regulatory limits by several times.
The study, published in Science of The Total Environment, found that turmeric samples from Patna in India and Karachi and Peshawar in Pakistan had lead levels surpassing 1,000 microgram/gram (μg/g). Turmeric from Guwahati and Chennai also showed lead levels above the regulatory limit set by the Food Safety and Standards Authority of India (FSSAI).
FSSAI’s Food Safety And Standards (Contaminants, Toxins And Residues) Regulations, 2011, set the regulatory limit for lead in whole and powdered turmeric at 10 μg/g.
The researchers warned that consuming turmeric with such high lead levels could lead to lead-poisoning in the region, especially among children.
Lead, a heavy metal, mimics calcium and gets stored in bones. It disrupts metabolic processes in humans, affects intelligence, and raises the risks of heart disease, kidney failure, and premature death.
Children with a blood lead level of 10 µg/L can lose 1 intelligence quotient point.
The study also reported that 815 million children globally have blood lead levels greater than 50 µg/L, while 413 million have levels above 100 µg/L.
Even a blood lead concentration as low as 3.5 µg/dL can link to reduced intelligence, behavioral issues, and learning difficulties in children.
The researchers collected turmeric samples from 23 major cities in India, Pakistan, Sri Lanka, and Nepal between December 2020 and March 2021. They found that 14% of the samples exceeded 2 μg/g of lead. The World Health Organization maintains that no amount of lead consumption is safe.
In Patna and Guwahati, researchers found the highest lead levels—2,274 μg/g and 127 μg/g, respectively. Both cities sourced their turmeric from Bihar.
The study identified polished turmeric roots as the most contaminated, followed by loose powder, packaged branded powder, and unpolished roots.
In India and Pakistan, the permissible lead levels are the same for both loose and packaged turmeric. National food safety authorities oversee lead testing.
Polished roots and loose powder showed lead levels exceeding 1,000 μg/g. Loose, under-regulated spices were more likely to be adulterated than packaged turmeric, the study emphasized.
Lead chromate, a yellow pigment used in paints, rubber, plastics, and ceramic coatings, likely contributed to the lead contamination. The study highlighted the link between lead chromate and lead poisoning in countries such as Bangladesh and the United States.
The researchers had previously studied the turmeric supply chain in Bangladesh, where they found a widespread practice of adding lead chromate to turmeric roots to improve their appearance and sell poor-quality roots. This practice dates back to the 1980s.
The study calls for future efforts to investigate the turmeric supply chain in the affected regions to identify the sources of lead chromate contamination.
