Overview
Woldetsadik and colleagues screened 40 turmeric and curry powders from Ethiopian, Kenyan and Ugandan markets by portable X-ray fluorescence to judge their value as mineral sources for refugees. Tables give potassium, calcium, manganese, iron, zinc, rubidium and strontium by origin and by branded versus non-branded turmeric. Arsenic and lead were measured but reported only as below 1 mg/kg with the data not shown, and the authors found no sign of lead chromate adulteration.
Key numbers
- Arsenic and lead in all turmeric and curry powders: “less than 1 mg kg−1 (Data not shown)” (Discussion, p. 6).
- Turmeric, Uganda: manganese “176 ± 47.3” mg/kg, zinc “36.7b ± 4.83” mg/kg (Table 1, p. 5).
- Curry powder, Ethiopia: iron “1.62a ± 0.81” g/kg (Table 1).
Methods (brief)
Powders were measured three times each in sealed sample cups with a benchtop-mounted portable XRF unit using the manufacturer’s calibrations. Detection limits ranged from 3.9 mg/kg (rubidium) to 1040 mg/kg (potassium); limits for arsenic and lead are not stated, and no reference material was run.
Evidence Fitness
For heavy metals this paper offers only a qualitative ceiling of 1 mg/kg for arsenic and lead, without detection limits, so it cannot support numeric occurrence values. Portable XRF without reference materials is a screening method. Curry powder is at most a seasoning proxy for brown-gravy, which is not linked.