Overview
Kakoma and Awofolu bought seven imported instant-noodle brands at four Windhoek outlets in each of four monthly rounds (48 samples) and measured zinc, cadmium, copper, lead and arsenic by ICP-OES. Per-brand values (triplicate means) are printed for each outlet and period, together with period and overall means and a health-risk assessment. Lead and arsenic gave target hazard quotients above one.
Key numbers
- Lead: “<0.05” mg/kg in most period I-II samples, not detected in period III, and 0.2 to 2.5 mg/kg in period IV; overall mean 0.4 mg/kg dry weight (Tables 2-6).
- Total arsenic: 0.2 to 2.5 mg/kg per sample; overall mean printed as 3.0 mg/kg in Table 6 but 1.4 mg/kg in the abstract.
- Cadmium: mostly “<0.05” or not detected, but 0.2 to 1.2 mg/kg in period III; overall mean 0.15 mg/kg (Tables 4 and 6).
Methods (brief)
The noodle cake was ground, sieved, digested with aqua regia and read by ICP-OES. Results are mg/kg dry weight, n=3 per value, with relative standard deviations in parentheses. No detection limit is defined and no certified reference material, recoveries or blanks are reported.
Evidence Fitness
A structured repeat-sampling design across outlets and months, but with no stated quality control. The period III cadmium values and period IV lead values jump sharply relative to other months without explanation, and the arsenic means in Table 6 do not match the per-period tables or the abstract. Whether the seasoning sachet was included and which flavors were bought is not stated. Instant noodles are direct evidence for noodles but only a proxy for chicken-noodle-soup and ramen-soup, which are not linked.