Lead pigment in turmeric is the culprit in a global poisoning mystery (2024)

I immediately tested the 5 year old Sadaf tumeric in my kitchen cabinet using a 3M lead testing kit I happened to have in my house. Thankfully it came out negative!

That doesn't sound technically plausible to me—there aren't any inexpensive tests. Do you mean something like this 3M product[0], that's intended for paint not food, and is documented as "LeadCheck™ Swabs reliabily detect lead in paints at 0.5% (5,000 ppm). 3M™ LeadCheck™ Swabs may indicate lead in some paint films as low as 0.06% (600ppm)."? If so, those aren't remotely suited for this purpose—those detection lower-bounds represent astronomically high amounts of lead, for a food item.

The highest end of Pb contamination in turmeric in Bangladesh (as in OP) is, from a cursory search, maybe 483 ppm [1]. Regulatory limits in the US are in the low parts-per-billion [2]. This metal bioaccumulates over a lifetime.

[0] (.pdf) https://multimedia.3m.com/mws/media/1581338O/3m-leadcheck-in...

[1] https://pubmed.ncbi.nlm.nih.gov/25214856/ ("Contaminated turmeric is a potential source of lead exposure for children in rural Bangladesh" / "Results: Lead concentrations in many turmeric samples were elevated, with lead concentrations as high as 483 ppm")

[2] https://www.consumerreports.org/babies-kids/baby-food/fda-pr...

Thanks for this heads up. This will be useful information for other people with the same idea I had.