Marincich et al. 2023 — Cadmium in chocolate bars, Polish market (EFSA EU-FORA)
This EFSA EU-FORA fellowship report presents cadmium occurrence data from chocolate bars purchased in Warsaw, Poland, and estimates dietary exposure for three Polish population groups (children 3–9 years, adolescents 10–17 years, adults 18–64 years). ICP-MS analysis of both milk chocolate and bitter chocolate samples found all products below EU maximum levels (Commission Regulation EC 1881/2006 as amended), and cadmium exposure from chocolate consumption did not exceed the EFSA CONTAM TWI of 2.5 µg/kg body weight per week for any population group.
Key numbers
ICP-MS (iCAP RQ, Thermo Scientific) with KED module and external standard calibration. LOQ: 0.001 µg/g ww. Standard EN 15763:2009, microwave mineralisation per EN 13805:2014 (HNO3 + H2O2 + yttrium internal standard at 210°C).
Cd occurrence in chocolate, wet weight:
- Milk chocolate: median 0.018 µg/g ww (18 ppb), P95 0.029 µg/g ww (29 ppb); EU maximum level for milk chocolate with ≥30% dry cocoa solids or chocolate with <50% dry cocoa solids: 0.30 µg/g
- Bitter chocolate: median 0.126 µg/g ww (126 ppb), P95 0.149 µg/g ww (149 ppb); EU maximum level for chocolate with ≥50% dry cocoa solids: 0.80 µg/g
All samples below applicable EU maximum levels. No left-censored data (all samples above LOQ of 0.001 µg/g).
Weekly Cd exposure from chocolate (at P95 occurrence × consumption × 7):
- Children (3–9 y): milk chocolate 0.037 µg/kg bw/week, bitter chocolate 0.063 µg/kg bw/week
- Adolescents (10–17 y): milk chocolate 0.014, bitter chocolate 0.031 µg/kg bw/week
- Adults (18–64 y): milk chocolate 0.004, bitter chocolate 0.010 µg/kg bw/week
All exposures well below EFSA TWI of 2.5 µg/kg bw/week. Consumption data from IZZ-FAO 2000 Polish survey via EFSA Comprehensive Food Consumption Database.
Methods (brief)
ICP-MS with KED, EN 15763:2009 in-house method. Microwave mineralisation EN 13805:2014. LOQ 0.001 µg/g. Yttrium internal standard. External standard calibration. No left-censored values in either chocolate matrix. EU-FORA fellowship report; primary analytical work performed at Institute of Agricultural and Food Biotechnology (IAFB), Warsaw.
Implications
Certification: Bitter chocolate at P95 = 149 ppb (0.149 µg/g ww) is well below the EU 800 ppb limit for ≥50% cocoa solids, but represents a meaningful Cd contribution relative to overall dietary exposure, particularly for frequent consumers. Milk chocolate at P95 = 29 ppb is very low.
Courses: Illustrates the cocoa content–Cd relationship: bitter chocolate has roughly 7× higher Cd median than milk chocolate, consistent with the literature on cocoa bean as the primary Cd source (shells concentrate Cd relative to nibs).
App: Cd in milk chocolate 18 ppb median / 29 ppb P95 ww; bitter chocolate 126 ppb median / 149 ppb P95 ww. Polish market 2022–2023.