Turmeric is marketed as a versatile spice for cooking and its anti-inflammatory properties. However, a study published in Environmental Science and Technology investigated potential sources of blood lead level contamination in Bangladesh. Investigators were able to pin-point lead chromate-adulterated turmeric as a factor by matching the specific lead isotope contained in blood samples.
Lead chromate had been introduced into turmeric production as a way to preserve the bright orange-yellow color traditionally associated with the spice. Researchers were not able to find direct evidence of adulteration outside the Bangladesh samples; however, they have warned that the periodic safety checks are most likely catching a fraction of the adulterated turmeric traded on the global market. This is supported by the fact that more than 15 brands of turmeric have been recalled due to lead levels since 2011.