Rusin et al. 2021 — Cd and Pb in 370 fresh, frozen, dried, and processed fruit and vegetable samples, Poland
Rusin et al. measured Cd and Pb in 370 samples of fruits and vegetables spanning fresh, frozen, dried, and processed forms purchased in Poland, constituting one of the largest Polish datasets for these matrices. The study is notable for directly comparing Cd and Pb concentrations across processing states — fresh, frozen, dried, and processed (canned/jarred) — for matched commodities, enabling quantification of how processing affects metal concentration relative to the fresh product. Drying consistently concentrated Cd and Pb on a dry-weight basis, with dried mushrooms and dried herbs showing the highest absolute Cd concentrations. Leafy vegetables showed higher Cd than root vegetables across all processing states. All fresh vegetable samples were below EU MRL limits (Regulation 1881/2006 as amended), while some dried products exceeded limits when recalculated on an as-consumed equivalent basis.
Key numbers
- 370 total samples: fresh, frozen, dried, processed fruits and vegetables; Polish retail
- Fresh leafy vegetables Cd: mean approximately 0.05–0.15 mg/kg fresh weight; range up to 0.40 mg/kg
- Fresh carrots/root vegetables Cd: mean approximately 0.02–0.05 mg/kg fresh weight
- Dried herbs and dried mushrooms: Cd concentrations up to 2–5 mg/kg dry weight (highest in dataset)
- Pb: generally below 0.10 mg/kg fresh weight in most fresh produce; some frozen samples slightly elevated
- Processing effect: freezing did not substantially alter Cd or Pb relative to fresh; drying concentrated metals proportional to water loss; canning/jarring showed variable effects
- Method: GFAAS; wet acid digestion with HNO₃/H₂O₂; QC with CRM
Methods (brief)
GFAAS; 370 samples; multiple processing states; Polish retail sourcing; EU regulatory comparison (Regulation 1881/2006); dietary risk assessment using EFSA tolerable weekly intakes.
Implications
Certification: Dried herbs and mushrooms are high-Cd ingredients that require scrutiny; their Cd density per serving is substantially higher than fresh equivalents due to concentration during drying. Courses: Processing state (fresh vs. dried) is a major modifier of metal burden per serving — not just per unit weight. This is a critical teaching point for product formulators using dried vegetable powders. App: Ingredient forms (fresh vs. dried/powdered) must be tracked separately in the app model; fresh vegetable Cd values cannot be directly applied to dried vegetable powder ingredients.