A team of researchers from Stanford University and icddr,b have identified that turmeric from Bangladesh is contaminated with lead. Turmeric is widely used in the country to give a yellow color to curries, clothes, traditional cosmetics, medicine, and insect repellent. After three years of research, the team identified that lead in turmeric and industrial pigments used to color the spice was the most likely cause of the lead poisoning in the country. The researchers also developed rapid tests to identify the presence of dangerous heavy metals in turmeric, which reduced the incidence of adulterated spice from 47% to no detectable lead.
https://stanmed.stanford.edu/turmeric-lead-risk-detect/