Overview
Dróżdż and colleagues measured 13 elements, including cadmium, chromium, nickel and lead, by ICP-OES in four wild blueberry samples and two cultivated highbush blueberry samples from central Poland. Results are fresh-weight means of triplicate determinations (Table 3). Cultivated berries had more cadmium than wild berries, which the authors tie to garden soil cadmium. Hot-water infusion leached little lead or cadmium (figure only).
Key numbers
- Wild blueberry W1 (12-year-old pine forest): lead “0.556 ± 0.063a” mg/kg, cadmium “0.004 ± 0.0003a” mg/kg (Table 3, p. 176).
- Cultivated blueberry C2 (garden plot): cadmium “0.040 ± 0.0015f” mg/kg, lead “0.315 ± 0.015b” mg/kg (Table 3).
- Lead ranged 0.266 to 0.556 mg/kg across all six samples, against a stated lead LOQ of 0.5 mg/kg (Tables 1 and 3).
Methods (brief)
Frozen berries were homogenized and digested in nitric and perchloric acids, then analyzed by ICP-OES. Two certified reference materials (herb and poplar leaves) agreed with certified values, and spike recoveries were 87 to 109 percent.
Evidence Fitness
Six single lots, each analyzed in triplicate, so the n of 3 reflects replicate measurements. Most lead and all copper means sit below the paper’s own LOQs, and the authors’ statement that lead is under the 0.2 mg/kg EU limit conflicts with the printed lead means; treat lead values with caution. Blueberry is an ingredient proxy for blueberry-muffin; no baked product was measured.