Kim et al. (year unknown) — Ultra-trace minerals in commercial dry dog foods: Cr, Ni, Mo, Si, Al
Forty-nine commercially available dry dog foods from US retail outlets were analyzed for chromium, nickel, molybdenum, silica, and aluminum by ICP-AES (Thermo Scientific iCAP 6500) at the USDA Robert Holley Center for Agriculture and Health, Ithaca, NY. Results were expressed per megacalorie (Mcal) of metabolizable energy and compared to WHO average daily human intake values. Chromium, molybdenum, and aluminum concentrations in all dog foods were above average human daily consumption on a caloric basis. Nickel and silica were comparable to human intake patterns, with outliers exceeding twice the upper range of human daily intake. No evidence of potential chronic toxic exposure was found based on presumptive intake extrapolated from WHO toxic intake concentrations. A wide range of silica intake (2.96-83.67 mg/1,000 kcal) may have implications for dogs prone to silica urolithiasis.
Key numbers
n=49 dry dog foods. Metals measured: Cr, Ni, Mo (molybdenum), Si (silica), Al. Cr, Mo, and Al: above average human daily consumption per caloric basis. Ni and Si: comparable to human intake patterns; outliers present. Silica range: 2.96-83.67 mg/1,000 kcal ME. No chronic toxic exposure risk identified. ICP-AES (axially viewed, 150mm lens for matrix interference reduction). Year of publication not determinable from the markdown file — date not stated; manifest assigns year unknown. Based on the journal (Dove Press, Veterinary Medicine: Research and Reports), likely 2013-2016 range based on the pet food recall context cited.
Methods (brief)
Dry dog food samples pulverized; 0.5 g portions digested with 60:40 HNO3-HClO4 + yttrium internal standard; heated at 120-195°C; ICP-AES. Concentrations normalized to ME per manufacturer data. Compared to WHO average daily intakes.
Implications
Certification: aluminum, chromium, and nickel levels in dry dog food provide a comparison reference point for these metals in manufactured food products. Aluminum concentrations above average human intake on a caloric basis across all tested dog foods is a potentially relevant data point for aluminum discussions.
Courses: useful as a secondary reference for Cr, Ni, and Al occurrence in manufactured food products, and for the regulatory gap (no AAFCO or NRC standards for these ultra-trace minerals in pet food).
App: dog food is not within the human food scope of the app; not applicable.