EFSA CONTAM 2009 — Cadmium in Food
Summary
This is the European Food Safety Authority Panel on Contaminants in the Food Chain Scientific Opinion on cadmium in food, adopted 30 January 2009 in response to Question No EFSA-Q-2007-138 from the European Commission. It establishes the EU tolerable weekly intake for cadmium at 2.5 µg per kilogram body weight per week, superseding the long-standing Joint FAO/WHO Expert Committee on Food Additives provisional tolerable weekly intake of 7 µg/kg b.w./week. The derivation anchors on renal tubular dysfunction measured via urinary beta-2-microglobulin through a group-based BMDL5 of 4 µg cadmium per gram creatinine, a chemical-specific adjustment factor of 3.9, and a one-compartment kinetic model fit to non-smoking Swedish women that translates a critical urinary cadmium of 1.0 µg/g creatinine into a daily dietary intake of 0.36 µg/kg b.w., rounded to a weekly intake of 2.5 µg/kg b.w. The Panel concluded that mean European adult exposure is close to or slightly exceeding the TWI, with subgroups including vegetarians, children, smokers, and residents of highly contaminated areas exceeding the TWI by approximately twofold, and recommended that population-level exposure be reduced.
Key numbers
Tolerable weekly intake established by this opinion:
| Parameter | Value |
|---|---|
| TWI | 2.5 µg Cd/kg body weight per week |
| Equivalent daily intake | 0.36 µg Cd/kg body weight per day |
| Superseded value | JECFA/SCF PTWI of 7 µg Cd/kg body weight per week |
Derivation parameters (p. 107–108):
| Parameter | Value |
|---|---|
| Critical endpoint | Renal tubular dysfunction |
| Biomarker | Urinary beta-2-microglobulin (B2M) |
| Exposure metric | Urinary cadmium (U-Cd) in µg/g creatinine |
| Group-based BMDL5 | 4 µg U-Cd/g creatinine |
| Chemical-specific adjustment factor (inter-individual variation in U-Cd) | 3.9 |
| Reference point (target U-Cd) | 1.0 µg Cd/g creatinine |
| Policy target | 95 percent of the population remain below the reference point by age 50 |
| Kinetic model basis | One-compartment model fit to non-smoking Swedish women, age 58-70 |
European dietary cadmium exposure estimates, adults (p. 107):
| Population | Mean (µg/kg b.w./week) | Range (µg/kg b.w./week) |
|---|---|---|
| Adults across EU countries | 2.3 | 1.9–3.0 |
| High consumers (95th percentile) | 3.0 | 2.5–3.9 |
| Vegetarians | up to 5.4 | — |
| Regular consumers of bivalve molluscs | 4.6 | — |
| Regular consumers of wild mushrooms | 4.3 | — |
Italian population subgroup data, dietary cadmium exposure (p. 48, Table 28):
| Age (years) | n | Mean (µg/kg b.w./week, 95% CI) | P95 (µg/kg b.w./week) |
|---|---|---|---|
| 0.5–6 | 88 | 3.46 (3.17–3.75) | — |
| 7–12 | 105 | 2.56 (2.37–2.74) | — |
| 0.5–12 | 193 | 2.97 (2.79–3.15) | 5.49 (4.95–6.08) |
| 13–94 | 1747 | 1.89 (1.85–1.94) | 3.63 (3.42–3.79) |
Mean dietary cadmium exposure for children 12 years of age or less was approximately 60 percent greater than for adults, primarily due to greater food consumption relative to body weight. A UK Total Diet Study (FSA 2009) separately reported that toddlers in the 1.5 to 4.5 year range had exposure 165 percent higher than adults.
Infant intake estimates from a Czech study of 35 breast milk samples from non-smoking mothers and 8 infant formula samples:
| Source | Median concentration | Estimated infant weekly intake |
|---|---|---|
| Breast milk | 0.5 µg/kg | 0.56 µg/kg b.w./week |
| Infant formula | 0.6 µg/kg | 0.67 µg/kg b.w./week |
Occurrence data analyzed: approximately 140,000 samples on cadmium occurrence in food commodities, collected 2003 to 2007 from 20 EU Member States. Highest cadmium concentrations were observed in seaweed, fish and seafood, chocolate, and foods for special dietary uses, with fungi, oilseeds, and edible offal as specific high-concentration items. For most foods fewer than 5 percent of samples exceeded the EU maximum level under Regulation (EC) No. 1881/2006 where specified; up to 20 percent of samples exceeded the ML for celeriac, horse meat, fish, and bivalve molluscs other than oysters and cephalopods.
Major dietary contributors to overall cadmium exposure in the EU general population (p. 107): cereals and cereal products, vegetables, nuts and pulses, starchy roots and potatoes, meat and meat products. The opinion includes per-country contribution breakdowns (Figure 7) showing considerable variation across Member States.
Toxicokinetic and general toxicology anchors from this opinion:
| Parameter | Value |
|---|---|
| Gastrointestinal absorption (general population) | 3–5 percent |
| Absorption range accounting for iron status and pregnancy | 1–10 percent |
| Biological half-life in kidney and liver | 10–30 years |
| IARC classification | Group 1 human carcinogen, based on occupational studies |
| Primary target organ | Proximal tubular cells of the kidney |
Methods (brief)
The opinion is a risk assessment combining occurrence data, consumption data, and dose-response modeling. Occurrence data were solicited from EU Member States and covered approximately 140,000 samples collected 2003 to 2007. Consumption data were drawn from EFSA’s Concise European Food Consumption database, with national dietary surveys used for specific sub-groups including French vegetarians and Italian children. Analytical methods across the reporting laboratories included ICP-MS and atomic absorption spectrometry variants; the opinion notes limit-of-detection differences across laboratories and addresses lower-bound / upper-bound treatment of non-detects.
The hazard characterization used a meta-analysis of studies relating urinary cadmium to urinary beta-2-microglobulin, fitting a Hill model separately for subjects over age 50 and for the whole population. The group-based BMDL5 of 4 µg U-Cd/g creatinine was divided by a chemical-specific adjustment factor of 3.9 for inter-individual variation in urinary cadmium to produce the reference point of 1.0 µg U-Cd/g creatinine. A one-compartment toxicokinetic model was then fit to a Swedish cohort of non-smoking women (age 58 to 70) that included both dietary cadmium intake and urinary cadmium; the model translates the 1.0 µg/g creatinine reference point at age 50 into the dietary intake that keeps 95 percent of the population below that urinary value. The Panel explicitly notes that no additional adjustment or uncertainty factor was applied for individual susceptibility because the underlying data were already drawn from an early-biological-response endpoint and a sensitive population.
Limitations the opinion itself flags: the Italian children data set is small (n = 88 toddlers, n = 105 children), cross-country variability in food contribution is substantial, and the genotoxicity and cancer data were deemed insufficient for quantitative dose-response modeling (hence the TWI rests on the renal endpoint, not on carcinogenicity).
Implications
- Certification: this is the EU reference value against which HMT&C cadmium thresholds should be calibrated for products entering or made in the European market. The TWI of 2.5 µg/kg b.w./week is the tighter of the two major international reference values for cadmium; JECFA’s 2010 PTMI corresponds to a higher weekly-equivalent value. HMT&C must decide whether to calibrate to EFSA or JECFA and name the rationale per the CLAUDE.md firewall rule. Calibrating to EFSA is the more conservative and more EU-market-compatible posture; calibrating to JECFA would need explicit rationale.
- Courses: the EFSA derivation is a clean teachable example of biomarker-anchored risk assessment (urinary B2M as the early tubular damage signal, U-Cd as the exposure metric, a toxicokinetic model to back-translate to dietary intake). The contrast with EPA IRIS (US) and ATSDR (US) derivations, pending ingest, will highlight how different agency procedures can produce different reference values from overlapping literature.
- App: the 140,000-sample occurrence dataset and the food-group contribution breakdowns seed high-confidence ingredient-level contamination profiles for cereals, leafy vegetables, root vegetables, potatoes, nuts, oilseeds, pulses, meat and offal, fish, molluscs, chocolate, and mushrooms. These should be attached as ingredient pages and their
contamination_profileblocks populated on the next ingest wave. Subgroup exposure data (vegetarians at 5.4 µg/kg b.w./week, bivalve consumers at 4.6, mushroom consumers at 4.3) justifiesvulnerable_population_flagsentries in the app layer. - Microbiome: not specifically addressed in this opinion; the broader microbiome-cadmium literature will enter through the Handbook on the Toxicology of Metals chapter ingest and dedicated microbiome-ingest work later.
Provenance notes
License class public-reference-only. EFSA’s scientific opinions are publicly available but not licensed for redistribution; the raw PDF is held privately under raw/ and the access_url points to the EFSA Journal landing page for verification. The DOI 10.2903/j.efsa.2009.980 resolves through doi.org to the same record.
A 2011 EFSA statement reaffirmed this TWI after JECFA published a divergent provisional tolerable monthly intake in 2010. That 2011 statement is not in the current raw corpus and is not represented by a source page yet; the regulation page efsa-cadmium-twi flags it as pending and will be updated when the 2011 document is ingested. The TWI established here remains the operative EU reference value regardless of the 2011 reaffirmation, because the 2011 statement did not change the numeric value.