Overview
Ogoko and colleagues measured eight metals by flame AAS in 40 non-alcoholic drinks from Aba supermarkets and report one mean per category for seven categories. Lead and cadmium exceeded drinking-water guideline values in every category. Results are per litre.
Key numbers
- Carbonated drinks: cadmium 0.075 ± 0.006 mg/l, lead 0.296 ± 0.082 mg/l (Table 1, p. 2579).
- Malt drinks: cadmium 0.063 ± 0.002 mg/l, lead 0.187 ± 0.022 mg/l (Table 1).
- Highest lead: yogurt 0.424 ± 0.096 mg/l; cobalt in wines below detection (Table 1).
Methods (brief)
5 mL digested with nitric, hydrochloric and perchloric acids (3:1:1) at 250 °C; flame AAS (Agilent 280FS). Detection limit 0.001 ppm for all metals; spike recoveries 89 to 101%; no certified reference material.
Evidence Fitness
Only category means are printed and the number of samples per category is not given. Several text statements contradict Table 1 (for example the iron range and mean, and which categories had the highest cadmium and lowest zinc). Carbonated and malt drinks are finished products and are only a proxy for soft-drink bases, sports-drink bases, lemon-lime soft drink and diet cola.