Tonska et al. 2020 — Pb and Cd in conventional vs. organic carrots, Poland
Tonska et al. compared Pb and Cd concentrations in 18 conventional and 18 organic carrot samples purchased at retail in Poland, and assessed dietary risk using EFSA/WHO tolerable weekly intake values. Organic and conventional carrots showed no statistically significant differences in Pb or Cd content, contradicting a common consumer assumption that organic produce has lower heavy metal burden. Both categories were below EU maximum residue limits for Pb (0.10 mg/kg fresh weight) and Cd (0.050 mg/kg fresh weight for carrots under EU Regulation 1881/2006), though individual samples approached those limits. The study provides a European baseline for carrot Pb and Cd from a major EU carrot-producing country.
Key numbers
- 36 carrot samples: 18 conventional, 18 organic; Polish retail
- Pb: conventional mean approximately 0.015–0.025 mg/kg fresh weight; organic mean similar (not significantly different)
- Cd: conventional mean approximately 0.012–0.020 mg/kg fresh weight; organic mean similar
- All samples below EU MRL for Pb (0.10 mg/kg) and Cd (0.050 mg/kg)
- Dietary risk assessment concluded exposure from carrot consumption well below EFSA/WHO tolerable intakes for both metals
- Method: FAAS or GFAAS (atomic absorption); wet weight basis
Methods (brief)
FAAS/GFAAS; 36 samples from Polish retail; wet acid digestion; EU regulatory comparison (Regulation 1881/2006); EFSA/WHO dietary risk assessment framework applied.
Implications
Certification: Organic labeling does not reduce Pb or Cd in carrots — soil history and geology are the primary drivers, not farming certification. This is a useful counterpoint to consumer assumptions. Courses: Illustrates that “organic” does not automatically mean lower heavy metals; the determinant is soil contamination history. App: Organic vs. conventional designation is not a reliable proxy for carrot Pb/Cd risk level.