Overview
Mehari and colleagues bought 49 foods from a Greensboro grocery store and measured nine elements, including lead, cadmium, chromium and nickel, by flame AAS after oven drying and nitric acid digestion. Cadmium, chromium and nickel were not detected in any food. Results are printed mainly as category summaries (average, maximum, minimum), with a few single foods named in the text.
Key numbers
- Lead, fresh fruits (n = 16): average 10, maximum 13, minimum 4.1 µg/g (Table 4).
- Lead, white coconut 13.4 µg/g and Chinese bitter melon 4.1 µg/g; “average lead (Pb) concentration of 6.98 μg/g in melon” (Section 3.3.1).
- Cadmium, chromium and nickel: below 0.1, 0.1 and 0.04 µg/g in all foods (Tables 3-6).
Methods (brief)
Diced food was oven dried at 55 °C, ground and digested in 6 M nitric acid, then analyzed by flame AAS with blank subtraction. Accuracy was checked by spike recovery (80 to 120%) and a repeat purchase 30 days later; no certified reference material was analyzed.
Evidence Fitness
Single purchases of each food from one store, category-level tables, and no reference material. Lead near 10 µg/g in every food group is far above levels typical of fruit and is hard to reconcile with flame AAS sensitivity, and the overall summary table conflicts with the category tables, so the lead data carry low confidence. The only melons were bitter melons, so for cantaloupe this is not even a close proxy and that page is not linked.