Wheat

Overview

Wheat is identified across EFSA Cd 2009 and JECFA 91st 2022 as one of the top population-level dietary cadmium contributors, with the bran and germ fractions carrying higher cadmium than refined endosperm.

Heavy metal contamination profile

Per-analyte snapshot derived from the machine-readable contamination_profile in the frontmatter above. data gap indicates the literature has been reviewed for this commodity-analyte combination and no usable occurrence data was found (a finding, not a placeholder). The Key sources column shows the top 2-3 contributing sources by year and sample size, with numbered wikilink aliases.

Synthesis basis and censoring treatment

The inorganic arsenic, aluminium and chromium cells were degenerate, each carrying a p95 equal to its typical maximum because a single value had been recorded as though it were a distribution. Re-reading the contributing sources shows two distinct patterns. Inorganic arsenic in wheat and wheat products sits at or below the reporting limit in regulated markets: the UK Total Diet Study returned all bread, flour and cereal composites below its 12 ppb inorganic-arsenic limit, and the Irish study reported cereals from 0 to 20 ppb against a 10 ppb detection limit (Baxter et al. 2015; FSAI 2016). This cell is therefore a left-censored bound that acknowledges low-level detection just above the limit; high-arsenic-groundwater regions, where wheat grain inorganic arsenic exceeds 200 ppb, are elevated context only (Shi et al. 2022; Kumar et al. 2024). Inorganic arsenic is kept strictly distinct from total arsenic and is not derived from it.

Aluminium and chromium have genuine distributions whose collapsed tails understated the spread. For aluminium, large commercial datasets cluster the central near 2000 to 4500 ppb, with a German wheat-grain median of 3000 ppb and a Polish rye-wheat-bread mean of 4054 ppb, and an upper tail reflecting the German wheat-grain maximum of 19000 ppb; the far-tail aluminium-additive and baking-driven values, including Irish cereals to 47100 ppb, belong to processing rather than the grain (Stahl et al. 2017; Balbo and Wozniak 2022). For chromium the prior central of 100 to 1000 ppb overstated clean wheat: Polish wheat grain ran a median of 27 ppb, UK cereals 5 to 10 ppb, and European breads by isotope dilution 5 to 202 ppb, all as total chromium with Cr-VI below its limit (Reczajska et al. 2005; Saraiva et al. 2021). General-market Ethiopian grain at 1570 ppb anchors the commercial right tail, while industrial karst grain and heavily contaminated Ghanaian cereals are elevated context excluded from the centre (Getu et al. 2022; Li et al. 2022; Oduro et al. 2023).

Why this commodity accumulates cadmium

Wheat takes up cadmium from soil through its root system, with uptake efficiency influenced by soil cadmium concentration, zinc status, soil pH, and cultivar. Durum wheat has been documented as a more efficient cadmium accumulator than common bread wheats, producing elevated cadmium in pasta-grade wheat products. Within the wheat kernel, cadmium partitions preferentially to the bran and germ rather than the endosperm, so refined white flour carries the lowest cadmium among common wheat derivatives and whole-wheat products carry the highest.

Ranges by source, region, and variety

Pending ingest of commodity-level occurrence data. EFSA 2009 Table 1 reports a mean cadmium concentration for wheat grain and flour of 0.030 mg/kg and for wheat bran and germ of 0.065 mg/kg, reflecting the approximately two-fold bran-over-endosperm concentration factor. Durum wheat, rice bran, and whole-wheat products in cadmium-elevated growing regions carry values above the category mean.

Processing effects

Pending. Milling that removes bran and germ lowers the cadmium content of the resulting flour relative to whole grain; fermentation and baking do not remove cadmium. Wheat-protein isolation (vital wheat gluten) concentrates cadmium from the source grain proportionally with protein enrichment.

Ingredient-derivative risk

Derivative wheat products vary substantially in cadmium content by the fraction of the kernel they represent. Refined white flour, semolina, and pasta made from refined wheat are at or near the endosperm-level mean; whole wheat flour, bran-enriched cereals, wheat bran supplements, and wheat germ products are above the whole-grain mean by the bran-concentration factor. Wheat protein products (vital wheat gluten, seitan) concentrate cadmium from the source grain; per-product characterization is necessary.

Mitigation options

Pending. Cultivar selection (non-accumulator lines), zinc amendment of soils (zinc-cadmium antagonism reduces plant cadmium uptake), soil pH management, and milling practices that remove bran and germ are the primary mitigation levers.

Other metals of concern

Some metals not listed in this section because no ingested source yet covers their commodity-level concern; those will populate when the corresponding source pages are ingested.

• Pb: the FDA Closer to Zero 20 ppb Pb action level for dry infant cereals applies to wheat-based infant cereal (FDA CTZ Pb 2025; see FDA Closer to Zero — 20 ppb Lead Action Level for Dry Infant Cereals).

Regulatory limits that apply

• Codex Alimentarius — Maximum Levels for Cadmium in Food — Codex matrix-level Cd ML for cereal grains (pending ingest of CXS 193-1995). The CCCF17 2024 discussion on quinoa (held separate from cereals at 0.15 mg/kg) recorded that one Member delegation cited cereals as a “serious contributor to exposure to cadmium” in their region, consistent with the wiki’s cross-source synthesis.
• Commission Regulation (EU) 2023/915 cadmium maximum levels — EU Cd maximum levels for cereals: 0.10 mg/kg (100 ug/kg) for cereals except listed rows; 0.050 mg/kg (50 ug/kg) for barley and rye; 0.15 mg/kg (150 ug/kg) for rice, quinoa, wheat bran, and wheat gluten; 0.18 mg/kg (180 ug/kg) for durum wheat; 0.20 mg/kg (200 ug/kg) for wheat germ.
• FDA Closer to Zero — 20 ppb Lead Action Level for Dry Infant Cereals — FDA CTZ 20 ppb lead action level for dry infant cereals is the adjacent Pb rule; any future Cd analogue under the CTZ program would apply similarly to wheat-based infant cereal.

Nickel in wheat

Flyvholm et al. 1984 reports wheat flour mean Ni at 0.13 µg/g (range 0.03 to 0.3 µg/g, n=32 samples) and whole wheat at 0.33 µg/g (range 0.1 to 0.8 µg/g, n=85). The roughly 2.5x concentration gap between whole-grain wheat and refined flour reflects the bran fraction’s accumulation of Ni, parallel to the bran-effect on Cd and Mn. In the Danish average diet model, wheat flour contributes 14.7 µg Ni/day (10 percent of total dietary Ni) at a load factor F = 1.9; wheat is therefore a meaningful per-day Ni source by volume, though not a high per-gram contributor on the order of cocoa, soy, or oats. Whole wheat at 0.33 µg/g is roughly 5x higher than white bread (0.27 µg/g, n=65 samples), supporting the bran-versus-endosperm pattern.

References

Works cited in this page’s text, in first-appearance order. This is not the full corpus for this page; it is only what the prose above draws on. The complete set of sources is listed under Sources below. Each title links to its source record, which carries the ingest receipt, the extracted values, and the file hash of the document it was built from.

1. Scientific Opinion of the Panel on Contaminants in the Food Chain on a request from the European Commission on cadmium in foodEFSA Panel on Contaminants in the Food Chain (CONTAM) · The EFSA Journal · 2009 · doi.org/10.2903/j.efsa.2009.980Government
2. Cadmium: dietary exposure assessmentJoint FAO/WHO Expert Committee on Food Additives · WHO Food Additives Series, No. 82 (Safety evaluation of certain contaminants in food, prepared by the 91st meeting of JECFA) · 2022 · www.who.intGovernment
3. Total Diet Study of metals and other elements in foodBaxter M and Brereton N · Food and Environment Research Agency report for the UK Food Standards Agency, Fera report 15/06, project FS102081 · 2015 · www.food.gov.ukGovernment
4. Report on a Total Diet Study Carried out by the Food Safety Authority of Ireland in the Period 2012–2014Food Safety Authority of Ireland (FSAI) · FSAI Chemical Monitoring and Surveillance Series · 2016 · www.fsai.ieGovernment
5. Sulfur reduces arsenic and cadmium translocation from root to shoot in wheat by regulating vacuolar sequestrationShi et al. · Frontiers in Plant Science · 2022 · doi.org/10.3389/fpls.2022.1032681Review
6. High Arsenic Contamination in the Breast Milk of Mothers Inhabiting the Gangetic Plains of Bihar: A Major Health Risk to InfantsKumar A and et al. · Environmental Health 23(1) · 2024 · doi.org/10.1186/s12940-024-01115-wReview
7. Migration of aluminum from food contact materials to food - a health risk for consumers? Part I of III: exposure to aluminum, release of aluminum, tolerable weekly intake (TWI), toxicological effects of aluminum, study design, and methodsStahl T, Falk S, Rohrbeck A, Georgii S, Herzog C, Wiegand A, et al. · Environmental Sciences Europe · 2017 · doi.org/10.1186/s12302-017-0116-yReview
8. Dietary exposure and risk characterisation of multiple chemical contaminants in rye-wheat bread marketed in PolandBalbo C and Wozniak L · EFSA Journal · 2022 · doi.org/10.2903/j.efsa.2022.e200911Government
9. Determination of Chromium Content of Food and Beverages of Plant OriginReczajska W, Jedrzejczak R, and Szteke B · Polish Journal of Food and Nutrition Sciences · 2005Review
10. Speciation analysis of Cr(III) and Cr(VI) in bread and breakfast cereals using species-specific isotope dilution and HPLC-ICP-MSSaraiva MA, Jitaru P, and Sloth JJ · Journal of Food Composition and Analysis · 2021 · doi.org/10.1016/j.jfca.2021.103991Review
11. Determination of the Level of Heavy Metals in the Selected Cereals from Debre Markos Local Market, Amhara Region, EthiopiaGetu A, Seid Y, and Asrade B · International Journal of Analytical Chemistry · 2022 · doi.org/10.1155/2022/7146439Review
12. Co-exposure of potentially toxic elements in wheat grains reveals a probabilistic health risk in Southwestern Guizhou, ChinaLi D, Zhang C, Li X, Li F, Liao S, Zhao Y, et al. · Frontiers in Nutrition · 2022 · doi.org/10.3389/fnut.2022.934919Review
13. Health risks of potentially toxic metals in cereal-based breakfast meals in the Kumasi Metropolis, GhanaOduro PA, Ankar-Brewoo G, Dodd M, Ansah E, Darko C, Borquaye LS, et al. · Discover Food 3:25 · 2023 · doi.org/10.1007/s44187-023-00067-3Review
14. Action Levels for Lead in Processed Food Intended for Babies and Young Children: Guidance for IndustryU.S. Food and Drug Administration · U.S. Department of Health and Human Services, Food and Drug Administration, Human Foods Program · 2025 · www.fda.govGuidance
15. Nickel Content of Food and Estimation of Dietary IntakeMari-Ann Flyvholm, Gitte Dalsgaard Nielsen, and Allan Andersen · Zeitschrift für Lebensmittel-Untersuchung und -Forschung 179(6):427-431 · 1984 · doi.org/10.1007/BF01043419Review

Sources

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Update history

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