Overview
Collumb and colleagues measured 14 elements, including cadmium, chromium, nickel, cobalt, barium, molybdenum and aluminum, by ICP-OES in 47 pastas and flours bought in Las Vegas in June 2018: 42 gluten-free rice-based products and 5 wheat pastas as controls. Table 1 prints every sample (dry weight, µg/kg) and Table 2 gives group statistics. Lead and arsenic were not measured.
Key numbers
- All products: cadmium mean 278 µg/kg, range 150 to 600 µg/kg (Table 2).
- Wheat pasta (n = 5): cadmium mean 260 µg/kg, range 200 to 350 µg/kg; chromium mean 1700 µg/kg (Table 2).
- Asian-imported gluten-free products: cadmium mean 333 µg/kg, maximum 500 µg/kg (Table 2).
Methods (brief)
Homogenized with a mortar and pestle, hot aqua regia digestion (USEPA 3050B) and ICP-OES (USEPA 6010B), in triplicate with RSD below 20%. A certified reference sample from a USEPA-certified supplier was checked; recoveries are not reported. Values below the instrument detection limit are printed as ”-“.
Evidence Fitness
Every sample is printed, but there is no lead or arsenic, recoveries are not given, and aqua regia digestion is not a total digestion. Cadmium levels are high for cereal products and may reflect the method. Dry pasta is a proxy only for canned-spaghetti, chicken-noodle-soup, macaroni-and-cheese, pie-crust and whole-wheat-pasta (the wheat pastas are not stated to be whole wheat); those pages are not linked.