Overview
Hexavalent chromium (Cr-VI, Cr(VI), or Cr6+) is the high-oxidation-state form of chromium found in chromate (CrO4^2-) and dichromate (Cr2O7^2-) anions. The species is operationally distinct from trivalent chromium (Cr3+), which is far less toxic and was historically (and contestedly) treated as an essential trace nutrient. The Heavy Metal Index maintains the Cr-VI / Cr(III) split throughout, treating hexavalent chromium as a separate analyte from total or trivalent chromium. Total chromium reported by a source is never substituted for Cr-VI on this wiki; sources that do not speciate are routed to chromium as total chromium and labeled as such. See also chromium for the parent element page.
Toxicology
Cr-VI crosses cell membranes through sulfate and phosphate transporters because the chromate and dichromate oxyanions resemble those nutrients structurally. Once inside the cell, Cr-VI is reduced to Cr(III) through reactive Cr-V and Cr-IV intermediates, generating reactive oxygen species and DNA damage along the way. The toxicology chapter Ufelle and Barchowsky 2021 characterizes Cr-VI as the high-concern carcinogenic chromium species and identifies its principal toxic endpoints as corrosive injury at high acute exposure, allergic contact dermatitis on chronic skin contact, acute renal injury after high-dose ingestion, and lung cancer and genotoxicity after inhalation exposure. The same chapter explicitly names chromium among the metals that can provoke immune reactions, alongside mercury, gold, platinum, beryllium, and nickel. Children and elderly individuals are highlighted as more susceptible than most adults at any given exposure level.
The carcinogenicity of Cr-VI is best characterized for inhalation exposure (occupational settings, chromate production, electroplating, leather tanning) where lung cancer is the canonical endpoint. The carcinogenicity of Cr-VI by ingestion is documented in animal studies and is the basis of the California OEHHA public-health goal for Cr-VI in drinking water and the related California maximum contaminant level. Ingested Cr-VI is partially reduced to Cr(III) in saliva and gastric fluid before systemic absorption, which complicates dose-response extrapolation from inhalation studies; the surviving systemic Cr-VI fraction is the toxicologically relevant dose for ingestion-route effects.
Typical exposure routes
Inhalation is the dominant occupational and environmental Cr-VI exposure route and is outside the dietary scope this wiki primarily tracks. The relevant Cr-VI exposure pathways for food and supply chain are drinking water used in food preparation, water and process water in the manufacturing chain, and contact with chromated stainless steel, chromated wood preservatives, or other chromate-bearing materials in equipment, packaging, or storage. Geogenic Cr-VI in groundwater is documented in regions with serpentinite or chromite-bearing geology and in some agricultural watersheds.
In finished food matrices, ambient Cr is overwhelmingly trivalent chromium, both because Cr-VI is oxidatively unstable in many food matrices and because the analytical methods that resolve speciation are uncommon in routine occurrence surveys. The result is that nearly all chromium occurrence data this wiki has cataloged report total chromium, not Cr-VI; the corpus contains a single peer-reviewed Cr-VI food-occurrence study at present. See the speciation gap section below.
Food sources and occurrence
Soares et al. 2000 is, at the time of this writing, the only food-occurrence source loaded on the wiki that reports Cr-VI explicitly rather than total chromium. The study used an ion-exchange separation followed by electrothermal atomization atomic absorption spectrometry to measure Cr-VI selectively in 20 commercial powdered milk infant formulas from the Portuguese market. In the seven newborn-formula samples, the reported Cr-VI mean was 24 ng/g and the source-scope range was below 10 to 75 ng/g, which is equivalent to mass-basis 24 ppb mean and below 10 to 75 ppb range; the lower end is censored at the method limit. Group means for follow-up and dietetic milk subgroups were 12 to 33 ng/g.
The Soares 2000 dataset is small, market-specific, and reports group means and ranges rather than sample-level values, so it provides direct Cr-VI occurrence context for the dairy-based powdered formula row but cannot, on its own, support a percentile calculation for Cr-VI. The occurrence row is retained as direct dairy / non-soy powdered formula context per the Cr-VI species discipline. The result is also useful as a Cr-VI method reference: it documents an analytical pathway for routine selective Cr-VI quantification in a complex food matrix.
Regulatory limits
No regulation in the current wiki corpus carries a Cr-VI maximum level for a food matrix. The regulatory instruments that do address hexavalent chromium specifically sit in adjacent domains, principally drinking water and consumer-product labeling, and two of them are now cited here.
California sets an enforceable drinking-water Maximum Contaminant Level for hexavalent chromium of 10 µg/L (0.010 mg/L), adopted by the State Water Resources Control Board on April 17, 2024 and effective October 1, 2024 (California — Maximum Contaminant Level for Hexavalent Chromium in Drinking Water). This MCL is species-specific to Cr-VI and is tighter than the total-chromium MCL of 50 µg/L it supplements; an earlier California Cr-VI MCL at the same value took effect in 2014 and was invalidated in 2017 for an inadequate economic-feasibility record before the present re-adoption. Hexavalent chromium is also listed under California Proposition 65, as a carcinogen since February 27, 1987 and as a developmental and reproductive toxicant since December 19, 2008, with a cancer No Significant Risk Level of 0.001 µg/day by inhalation and a reproductive Maximum Allowable Dose Level of 8.2 µg/day by the oral route (California Proposition 65 — Hexavalent Chromium Listing and Safe-Harbor Levels).
Both instruments are drinking-water or product-labeling measures, not food maximum levels. The MCL governs the concentration of Cr-VI permitted in public-water-system water, and the Proposition 65 listing governs consumer-product warning obligations; neither sets a permitted concentration in a food. The other frameworks that touch hexavalent chromium remain un-ingested: the US EPA national primary drinking-water regulation sets a total-chromium MCL (100 µg/L) that is not Cr-VI-specific, occupational exposure limits (OSHA, NIOSH, ACGIH) are inhalation values, and Codex Alimentarius general standards do not separately specify Cr-VI for food. The practical consequence is unchanged: there is at present no food-specific regulatory benchmark for Cr-VI, so any concentration of toxicological concern for a food matrix is derived from drinking-water-derived toxicology and a thin food-occurrence base, not from a food-specific regulatory limit.
Testing methods
Selective Cr-VI quantification in food matrices is non-trivial because total digestion methods (microwave-assisted nitric acid digestion typical of ICP-MS occurrence surveys) reduce Cr-VI to Cr(III) and report only total chromium. Speciation-preserving methods route the chromium-bearing analyte through an ion-exchange or chromatographic step before quantification. Soares 2000 used Chromabond NH2 anion-exchange retention of chromate followed by nitric-acid elution and electrothermal atomic absorption at 357.9 nm; modern speciation work more typically uses ion chromatography coupled to ICP-MS with isotope-dilution standards or post-column hydride generation. Drinking-water Cr-VI is most commonly measured by EPA Method 218.7 (ion chromatography with post-column reaction).
A dedicated chromium-speciation testing page in testing is a near-term addition; the current testing index does not yet carry a Cr-VI-specific entry.
Microbiome effects
The current wiki corpus does not carry a microbiome-Cr-VI mechanism page. Cr-VI’s documented intracellular reduction by gastric and intestinal contents implies a real interaction with the gut microbial environment, but the metals/microbiome literature within this corpus is silent on Cr-VI specifically. Cr-VI microbiome content should be drafted when peer-reviewed mechanism or taxon-level evidence is added; it would crosswalk to WikiBiome as a Cr-VI-specific microbial-axis page.
Vulnerable populations
Infants and young children fed reconstituted powdered formula are the principal Cr-VI dietary vulnerable group identifiable from the loaded corpus. Cr-VI exposure assessment for this population would draw from formula Cr-VI concentration (Soares 2000 type data), water Cr-VI concentration (jurisdiction-specific drinking-water surveys not yet ingested), and reconstitution volume per serving. Body-weight-normalized Cr-VI intake is a more stringent test of exposure adequacy than absolute concentration because infant intake per kilogram body weight far exceeds adult intake per kilogram body weight. Children and elderly individuals are flagged in Ufelle and Barchowsky 2021 as more susceptible than most adults at any given exposure level.
The speciation gap
This is the most important short-term finding for the Cr-VI page. The wiki currently has total-chromium occurrence data from at least seven peer-reviewed and government sources that explicitly disclaim Cr-VI measurement: Chuchu et al. 2013, UK FSA 2016, Milani et al. 2023, Chekri et al. 2019, Chung et al. 2021, Meli et al. 2024, and the broader survey ecosystem. Each of these sources reports total chromium with an explicit note that the chromium quantity is not speciated. None of them can be substituted for Cr-VI under the species-discipline rule that total chromium is never reported as Cr-VI.
The result is that the loaded corpus has many total-chromium values and exactly one Cr-VI dataset (Soares 2000, n=20, Portugal, 2000). For any application that requires category-representative Cr-VI occurrence data, this is a structurally weak evidence base: a single small market-specific dataset cannot characterize a food-matrix Cr-VI distribution, and the literature does not at present support a food-specific Cr-VI concentration of toxicological concern. Closing the gap requires either commissioning Cr-VI speciation work for category-representative samples, or surfacing additional Cr-VI-specific peer-reviewed studies from the broader ingest corpus that have not yet been promoted to source pages.
Open questions
How does Cr-VI in finished powdered formula relate to Cr-VI in the reconstitution water? Soares 2000 used doubly deionized water for reconstitution, isolating the dry-product Cr-VI signal. A real-feeding Cr-VI exposure depends on both the powder and the tap or bottled water used to prepare it. The two-component exposure model is missing from the loaded corpus.
What is the rate at which dietary Cr-VI is reduced to Cr(III) in saliva and gastric fluid before absorption, and how does that rate vary with infant gastric pH? Infant gastric pH is higher (less acidic) than adult gastric pH, which would reduce the Cr-VI to Cr(III) conversion efficiency before systemic absorption and elevate the systemic Cr-VI dose per unit of ingested Cr-VI. This is a quantitative gap with direct consequences for infant Cr-VI exposure assessment and is not currently characterized in the corpus.
What Cr-VI speciation evidence exists outside the infant-formula matrix? Drinking water and produce grown on chromite-bearing or chromated-irrigation soils are the obvious candidate matrices. The current ingest is silent on these.
How do supply-chain Cr-VI exposures (chromated wood pallets, chromate-containing process equipment, chromated leather and gelatin) propagate into finished food? This is a manufacturing and packaging question, not a primary-agriculture question, and the loaded sources do not address it.
Frequently asked questions
What is hexavalent chromium and how is it different from regular chromium?
Hexavalent chromium (Cr-VI) is the high-oxidation-state form of chromium found in chromate and dichromate anions, and it is operationally distinct from trivalent chromium (Cr3+), which is far less toxic and was historically treated as an essential trace nutrient. The wiki keeps the two species separate throughout and never substitutes total chromium reported by a source for Cr-VI. Sources that do not distinguish the species are routed to the total-chromium page and labeled as such.
Why is hexavalent chromium considered harmful?
Once inside a cell, Cr-VI is reduced to Cr(III) through reactive intermediates, generating reactive oxygen species and DNA damage along the way. According to Ufelle and Barchowsky 2021, its principal toxic endpoints are corrosive injury at high acute exposure, allergic contact dermatitis on chronic skin contact, acute renal injury after high-dose ingestion, and lung cancer and genotoxicity after inhalation. Its carcinogenicity is best characterized for inhalation exposure, while carcinogenicity by ingestion is documented in animal studies.
How would hexavalent chromium get into food?
Inhalation is the dominant Cr-VI exposure route but falls outside this wiki’s dietary scope. For food and the supply chain, the relevant pathways are drinking and process water used in food preparation and manufacturing, and contact with chromated stainless steel, chromated wood preservatives, or other chromate-bearing materials in equipment, packaging, or storage. Geogenic Cr-VI in groundwater is documented in regions with serpentinite or chromite-bearing geology and in some agricultural watersheds.
How much hexavalent chromium is actually found in food?
The wiki notes that in finished food matrices ambient chromium is overwhelmingly trivalent, and nearly all occurrence data report total chromium rather than Cr-VI. The only food-occurrence source that reports Cr-VI explicitly is Soares et al. 2000, which measured 20 commercial powdered milk infant formulas from the Portuguese market; the seven newborn-formula samples had a Cr-VI mean of 24 ppb and a range from below 10 to 75 ppb, with the low end censored at the method limit. That dataset is small and market-specific, so it provides context for dairy-based powdered formula but cannot support broad conclusions on its own.
Are there legal limits on hexavalent chromium in food?
No regulation in the current wiki corpus sets a Cr-VI maximum level for a food matrix. The frameworks that do impose Cr-VI limits are in adjacent domains, including drinking-water standards such as California’s state-level Cr-VI maximum contaminant level of 10 ug/L, occupational inhalation exposure limits, and California Proposition 65 listings of Cr-VI as a carcinogen and reproductive toxicant. Codex Alimentarius general standards do not separately specify Cr-VI for food.
Why is it so hard to test food specifically for hexavalent chromium?
Selective Cr-VI measurement is difficult because the total digestion methods typical of routine occurrence surveys, such as microwave-assisted nitric acid digestion for ICP-MS, reduce Cr-VI to Cr(III) and report only total chromium. Speciation-preserving methods must route the analyte through an ion-exchange or chromatographic step first; modern work typically uses ion chromatography coupled to ICP-MS, and drinking-water Cr-VI is most commonly measured by EPA Method 218.7. Because speciation methods are uncommon in routine surveys, the wiki holds many total-chromium values but only one Cr-VI food dataset.
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.
- Toxic Effects of Metals (Chapter 23), in Casarett & Doull’s Essentials of Toxicology, Fourth EditionTextbook
- Selective Determination of Chromium (VI) in Powdered Milk Infant Formulas by Electrothermal Atomization Atomic Absorption Spectrometry after Ion ExchangeReview
- The aluminium content of infant formulas remains too highReview
- Survey of metals in commercial infant foods, infant formula and non-infant specific foodsGovernment
- Trace Elements in Soy-Based Beverages: A Comprehensive Study of Total Content and In Vitro BioaccessibilityReview
- Trace element contents in foods from the first French Total Diet Study on infants and toddlersReview
- Content and Dietary Exposure Assessment of Toxic Elements in Infant Formulas from the Chinese MarketReview
- Chemical characterization of baby food consumed in ItalyReview
Sources
Auto-generated from source-page frontmatter. The "Used on this page for" column is populated by the orchestrator's POPULATE-SOURCE-LEGEND action; pending entries appear as *[awaiting synthesis]*.
| # | Citation | Year | Type | Used on this page for |
|---|---|---|---|---|
| 1 | Ioniță et al. 2026. Molecular and Cellular Mechanisms of Plant Responses to Heavy Metal Stress in Mining-Impacted Environments, Plants | 2026 | Peer-reviewed | Cd, Pb, tAs, Ni, Cr, Cr-VI occurrence in Narrative synthesis review; no primary measurements. |
| 2 | Alblooshi 2025. The impact of perfumes and cosmetic products on human health: a narrative review, Frontiers in Toxicology 7:1646075 (Frontiers in Toxicology; published 29 August 2025; corrected 16 December 2025) | 2025 | Review | US/EU/CA Pb, Cd, tHg, tAs, Ni, Cr, Cr-VI occurrence in Single-author narrative review compiling peer-reviewed literature published 2005–2025 on health impacts of perfumes and cosmetic products. Sources drawn… |
| 3 | Cwielag-Drabek et al. 2025. Heavy Metal Content in Tattoo and Permanent Makeup Inks and European Standards-Is There Still a Health Risk?, Toxics | 2025 | Peer-reviewed | EU Pb, Cd, Zn, Cr, Cr-VI, Ni, Cu, iAs, Co, Sb, Se, Mn, tHg occurrence in Commercial tattoo inks, permanent makeup inks, and dual-use inks purchased in the European Union in 2022-2023 (n=41) |
| 4 | Hardy 2025. Substances in tattoo inks and permanent make-up: restriction decision, UK REACH restriction decision report, Department for Environment, Food and Rural Affairs | 2025 | Government report | GB Ni, Cr-VI occurrence in UK REACH regulatory decision for tattoo inks and permanent make-up, drawing on the Health and Safety Executive Agency… |
| 5 | Jităreanu et al. 2025. An Overview of Heavy Metals in Cosmetic Products and Their Toxicological Impact, Applied Sciences 15: 12883 | 2025 | Review | EU/US/CA Pb, Cd, tHg, tAs, iAs, Cr, Cr-VI, Ni, Al, Fe, Cu, Zn, Co occurrence in Narrative review of heavy-metal contamination in cosmetics; literature 1990 - November 2025 retrieved via PubMed, Web of Science,… |
| 6 | National Health and Medical 2025. Australian Drinking Water Guidelines 6 2011 Version 4.0 Updated June 2025, National Water Quality Management Strategy | 2025 | Government report | AU Al, Sb, tAs, Cd, Cr-VI, Pb, tHg, Ni concentrations |
| 7 | Yang et al. 2025. The Strategies Microalgae Adopt to Counteract the Toxic Effect of Heavy Metals, Microorganisms | 2025 | Review | CN Cr, Cr-VI, Cd, tAs, Ni, Cu, tHg, Pb, Zn occurrence in Narrative review of microalgal heavy-metal removal strategies. No primary sampling, no PRISMA, no quantitative synthesis. Authors at Sichuan… |
| 8 | Aishwarya et al. 2024. Role of Extremophiles in the Removal of Heavy Metal and E-Waste, Trends in Biotechnology of Polyextremophiles (Shah MP, Dey S, eds.), Springer Nature, Chapter 15, pp. 361-371 | 2024 | Review | Pb, Cd, Cr, Cr-VI, Ni, Cu, tHg, tAs, Zn occurrence in Narrative book-chapter review of extremophile microbiology in heavy-metal bioremediation and e-waste remediation. No primary sampling, no PRISMA, no… |
| 9 | Board 2024. California SWRCB DDW-21-003 Hexavalent Chromium MCL regulation text, SWRCB-DDW-21-003 regulation text | 2024 | Government report | US-CA Al, Sb, tAs, Cd, Cr-VI, Cr-total, tHg, Ni concentrations |
| 10 | EPA 2024. IRIS Toxicological Review of Hexavalent Chromium [Cr(VI)] (CASRN 18540-29-9), EPA/635/R-24/164Fa, Integrated Risk Information System, Center for Public Health and Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency, Washington, DC | 2024 | Government report | US Cr-VI, Cr concentrations |
| 11 | EPA 2024. EPA’s Safer Choice and Design for the Environment (DfE) Standard (August 2024), U.S. EPA Safer Choice Program, Office of Pollution Prevention & Toxics (federal program standard document; first issued June 2009 as the DfE Standard for Safer Products; revised April 2011, September 2012, February 2015 as EPA’s Safer Choice Standard; current August 2024 revision) | 2024 | Government guidance | US Cd, Pb, Hg, Cr-VI occurrence in Not applicable: federal program standard document. The 36-page Standard body (plus four annexes A-D giving sample partnership-agreement templates)… |
| 12 | Ewubare et al. 2024. An Academic Review on Heavy Metals in the Environment: Effects on Soil, Plants Human Health, and Possible Solutions, American Journal of Environmental Economics 3(1) 70-81 | 2024 | Review | NG Pb, Cd, tHg, MeHg, Cr, Cr-VI, tAs, Ni, Cu, Zn, Mn, Co, Sb, Tl, Mo occurrence in Narrative review article; no primary samples. Synthesizes literature retrieved from Google Scholar, Frontier in Microbiology, AJOL, Scopus, Web… |
| 13 | Luo et al. 2024. Peptides Used for Heavy Metal Remediation: A Promising Approach, International Journal of Molecular Sciences | 2024 | Peer-reviewed | Pb, Cd, tHg, Cr, Cr-VI, Ni, tAs occurrence in Narrative review; no primary measurements. |
| 14 | Association 2024. OEKO-TEX® Limit values: New regulations 2024, OEKO-TEX® Service GmbH customer information notice, 09 January 2024, Zurich, Switzerland. Updates applicable test criteria, limit values, and requirements for the OEKO-TEX® STANDARD 100, ORGANIC COTTON, LEATHER STANDARD, ECO PASSPORT, and STeP certification labels; new values binding from 01 April 2024 after a three-month transition period. | 2024 | Industry | INT/EU/CH Pb, Cd, tAs, Sb, Cr, Cr-VI, Ni, tHg occurrence in Not a primary-measurement study. The notice publishes the OEKO-TEX Association’s updated 2024 limit values for the STANDARD 100,… |
| 15 | Si et al. 2024. Research progress in the detection of trace heavy metal ions in food samples, Frontiers in Chemistry | 2024 | Review | CN Pb, Cd, tHg, Cr-VI, Cu, Zn, Fe occurrence in Mini-review of nanomaterial-based analytical methods for trace heavy-metal detection in food samples; covers electrochemical, colorimetric, and fluorescence sensing… |
| 16 | Song et al. 2024. Development of a Fast Method Using Inductively Coupled Plasma Mass Spectrometry Coupled with High-Performance Liquid Chromatography and Exploration of the Reduction Mechanism of Cr(VI) in Foods, Toxics 12(5): 325 | 2024 | Peer-reviewed | CN Cr-VI, Cr occurrence in Seven commercially purchased food samples from a local supermarket in Nanjing, China — milk powder, rice flour, whole… (n=7) |
| 17 | California State Water Resources Control Board 2024. California Hexavalent Chromium Drinking-Water Maximum Contaminant Level Regulation (SWRCB-DDW-21-003), California State Water Resources Control Board | 2024 | Regulation | US-CA Cr-VI occurrence in Regulatory instrument. California Code of Regulations Title 22 maximum contaminant level for hexavalent chromium, applicable to all community… |
| 18 | Yang et al. 2024. Metallothionein: A Comprehensive Review of Its Classification, Structure, Biological Functions, and Applications, Antioxidants | 2024 | Peer-reviewed | Cd, Pb, iAs, Cr-VI, Ni, tHg occurrence in Narrative review; no primary measurements. |
| 19 | ATSDR 2023. Exposure Dose Guidance for Soil/Sediment Dermal Absorption (Version 3), ATSDR / U.S. Department of Health and Human Services - Public Health Service | 2023 | Government report | US As, Cd, Pb, Hg, MeHg, Ni, Cr, Cr-VI, Sb, Ba, Cu, Mn, Se, Ag, Tl, V, Zn, Be occurrence in Regulatory exposure-assessment guidance; no original sampling. Default ABSd and adherence-factor values from EPA RAGS Part E (2004); skin-surface… |
| 20 | Napier et al. 2023. Childhood Lead Exposure Linked to Apple Cinnamon Fruit Puree Pouches — North Carolina, June 2023–January 2024, Morbidity and Mortality Weekly Report | 2023 | Peer-reviewed | US Pb, Cr-VI occurrence in Children aged 1–3 years in North Carolina with confirmed blood lead levels ≥5 µg/dL linked to apple cinnamon… (n=22) |
| 21 | CIRS – C&K Testing (Hangzhou C&K Testing Technic Co. 2023. REACH ANNEX XVII — Restrictions on the Manufacture, Placing on the Market and Use of Certain Dangerous Substances, Mixtures and Articles, CIRS – C&K Testing (Hangzhou C&K Testing Technic Co., Ltd), Hangzhou, China; downloadable consolidated reproduction of Annex XVII to EU REACH Regulation (EC) No 1907/2006; document header states ‘Last update: 2023-07-17’. 64 pages, two-column ‘Column 1 (substance or group) / Column 2 (conditions of restriction)’ tabular layout reproducing entries 1 through 77. | 2023 | Industry | EU Pb, Cd, tHg, iHg, Cr-VI, Ni, tAs, Sn occurrence in Not a primary-measurement study. The document is a third-party reproduction of Annex XVII to EU REACH Regulation (EC)… |
| 22 | Deka et al. 2023. Monitoring Strategies for Heavy Metals in Foods and Beverages: Limitations for Human Health Risks, IntechOpen (Heavy Metals – Recent Advances) | 2023 | Book chapter | IN Pb, Cd, tHg, Cr, Cr-VI, tAs, Ni, Al, Sb, Mn, Fe, Co, Ba, Be occurrence in Narrative review chapter; no primary samples. Surveys analytical and remediation literature for heavy metals across foods and beverages… |
| 23 | ECHA 2023. Investigation report to support the Commission on the preparation of a restriction proposal for the use and presence of CMR 1A or 1B substances in childcare articles based on REACH Article 68(2), European Chemicals Agency (ECHA), Helsinki, Finland. Investigation report version 2.0 (Final), 31 October 2023, prepared at the request of the European Commission under REACH Article 68(2). | 2023 | Regulatory agency report | EU Pb, Cd, Cr-VI, Co, tAs, tHg, Sn, Li, V occurrence in Not a primary-measurement study. The report aggregates 1,559 entries reporting measurements of CMR 1A or 1B substances in… |
| 24 | Gautam 2023. Health Risk Assessment: Heavy Metals (Antimony, Arsenic, Barium, Cadmium, Chromium, Lead, Mercury, and Nickel) in Tattoo Ink (Intra-Dermal Contact), Institute of Environmental Science and Research Limited (ESR) client report FW23035, prepared for Manatu Hauora/Te Whatu Ora | 2023 | Government report | NZ/EU/US Ba, Pb, Ni, Cr-VI, tHg, Cd, Sb, tAs occurrence in Agency health-risk assessment using maximum tattoo-ink metal concentrations selected from the 2012 New Zealand Ministry of Health survey… (n=169) |
| 25 | He et al. 2023. In Situ Growth of Ti3C2/UiO-66-NH2 Composites for Photoreduction of Cr(VI), Catalysts | 2023 | Peer-reviewed | CN Cr-VI, Cr, Ti occurrence in Six photocatalyst conditions tested against synthetic potassium dichromate solution: Ti3C2, UiO-66-NH2, and Ti3C2/UiO-66-NH2 composites containing 5, 10, 15,… (n=6) |
| 26 | Hu et al. 2023. One-Pot Fabrication of 2D/2D CdIn2S4/In2S3 Heterojunction for Boosting Photocatalytic Cr(VI) Reduction, Catalysts | 2023 | Peer-reviewed | CN Cr-VI, Cr, Cd occurrence in Five photocatalyst conditions tested against synthetic aqueous Cr(VI): CdIn2S4 (CIS), In2S3 (IS), 0.25 CISI, 0.5 CISI, and 0.75… (n=5) |
| 27 | Meng et al. 2023. The innovative and accurate detection of heavy metals in foods: A critical review on electrochemical sensors, Food Control | 2023 | Review | CN/WHO Pb, Cd, iAs, tHg, Cr, Cr-VI, Cu, Zn, Ag occurrence in Critical review of the electrochemical-sensor literature (through ~2022) for heavy-metal detection in food matrices. |
| 28 | Nazari et al. 2023. Impacts of Heavy Metals in Seed Crops and Oil Seed on Human Health: A Threat to Food Safety — Review, Carpathian Journal of Food Science and Technology, 15(2), 106-124 | 2023 | Review | global/EU/IR Pb, Cd, iAs, tAs, tHg, MeHg, Ni, Cr, Cr-VI occurrence in Narrative literature review of published studies on heavy metal occurrence in oilseeds (sunflower, pumpkin, sesame, rape, mustard, linseed,… |
| 29 | New York State Department 2023. Toxic Chemicals in Children’s Products Program: Chemicals and Practical Quantitation Limits Under Consideration (Draft Update, Feb. 2023), NY DEC Toxic Chemicals in Children’s Products Program — stakeholder draft for public comment | 2023 | Regulation | US-NY Sb, tAs, Cd, Cr, Cr-VI, Pb, tHg, MeHg, Ni occurrence in Draft regulatory chemical list — proposes Chemicals of Concern (COCs) and High Priority Chemicals (HPCs) plus practical quantitation… |
| 30 | Shi et al. 2023. Effect of External Aeration on Cr (VI) Reduction in the Leersia hexandra Swartz Constructed Wetland-Microbial Fuel Cell System, Applied Sciences | 2023 | Peer-reviewed | CN Cr, Cr-VI, Cr-III occurrence in Five lab-scale up-flow Leersia hexandra constructed-wetland microbial-fuel-cell reactors treating synthetic Cr(VI) wastewater at five cathode dissolved-oxygen conditions (3.0,… (n=5) |
| 31 | Vasilachi et al. 2023. Analysis of Heavy Metal Impacts on Cereal Crop Growth and Development in Contaminated Soils, Agriculture | 2023 | Review | Pb, Cd, tAs, Cr, Cr-VI, Ni, Al, tHg, MeHg occurrence in Narrative literature review synthesising prior studies on cereal crops (wheat, rice, maize, barley, rye, oats, millet) grown in… |
| 32 | Yang et al. 2023. Asymmetric Alternative Current Electrochemical Method Coupled with Amidoxime-Functionalized Carbon Felt Electrode for Fast and Efficient Removal of Hexavalent Chromium from Wastewater, Nanomaterials | 2023 | Peer-reviewed | CN Cr-VI, Cr occurrence in One amidoxime-functionalized commercial carbon-felt electrode tested against prepared Cr(VI) wastewater solutions in batch adsorption and asymmetric-AC flow-through electrochemical… (n=1) |
| 33 | California Department of Justice, 2022. People of the State of California v. McWane, Inc. (dba AB&I) — Complaint for Injunctive Relief and Civil Penalties (Prop 65 hexavalent chromium air emissions, AB&I Foundry, East Oakland), Superior Court of California, County of Alameda (filed 15 February 2022 by Attorney General Rob Bonta; Supervising Deputy Attorney General Christie Vosburg; Deputy Attorney General Erin Ganahl) | 2022 | Regulatory | US-CA Cr-VI occurrence in Not a primary sampling study. The complaint is a civil enforcement pleading filed by the California Attorney General’s… |
| 34 | Office of the Attorney 2022. Complaint for Injunctive Relief and Civil Penalties — People of the State of California v. McWane, Inc. (AB&I Foundry), Superior Court of California, County of Alameda (filed 15 February 2022) | 2022 | Legal filing | US-CA Cr-VI concentrations |
| 35 | Ma et al. 2022. Application of Cerium Dioxide Nanoparticles and Chromium-Resistant Bacteria Reduced Chromium Toxicity in Sunflower Plants, Frontiers in Plant Science | 2022 | Peer-reviewed | Cr, Cr-VI occurrence in Pot experiment: sunflower grown in chromium-contaminated soil (0, 25, 50 mg/kg) treated with cerium dioxide nanoparticles and Staphylococcus… |
| 36 | Riyazuddin et al. 2022. A Comprehensive Review on the Heavy Metal Toxicity and Sequestration in Plants, Biomolecules | 2022 | Peer-reviewed | Cd, Pb, tAs, tHg, Cr, Cr-VI, Ni, Al occurrence in Narrative review; no primary measurements. |
| 37 | Sacchi et al. 2021. Natural Background Levels of Potentially Toxic Elements in Groundwater from a Former Asbestos Mine in Serpentinite (Balangero, North Italy), Water | 2021 | Peer-reviewed | IT/EU Cr, Cr-VI, Co, Ni, Mn, Fe, Zn occurrence in Thirty groundwater monitoring stations (29 retained after pre-selection) sampling four hydrogeological formations around the former Balangero chrysotile asbestos… (n=30) |
| 38 | Saraiva et al. 2021. Speciation analysis of Cr(III) and Cr(VI) in bread and breakfast cereals using species-specific isotope dilution and HPLC-ICP-MS, Journal of Food Composition and Analysis | 2021 | Peer-reviewed | FR/DK/EU Cr, Cr-VI occurrence in Selection of bread and breakfast cereal samples analysed at Anses (France) and Technical University of Denmark; exact n… |
| 39 | Saraiva et al. 2021. Chromium speciation analysis in raw and cooked milk and meat samples by species-specific isotope dilution and HPLC-ICP-MS, Food Additives & Contaminants Part A 38(2):304-314 | 2021 | Peer-reviewed | Cr-VI concentrations in milk and dairy (n=30) by ICP-MS |
| 40 | Saraiva et al. 2021. Development and validation of a single run method based on species specific isotope dilution and HPLC-ICP-MS for simultaneous species interconversion correction and speciation analysis of Cr(III)/Cr(VI) in meat and dairy products, Talanta 222 (2021) 121538 | 2021 | Peer-reviewed | FR/DK Cr, Cr-VI occurrence in Three composite food matrices acquired from retail shops in Maisons-Alfort, France for method validation: baby milk (500 mL… (n=3) |
| 41 | Villarreal et al. 2021. Ensuring toy safety from hexavalent chromium to meet European regulations using IC-ICPMS quantification, Thermo Fisher Scientific Application Brief AB000383, EMEA Customer Solution Center, Paris, France | 2021 | Industry | EU Cr-VI occurrence in Three method-validation samples drawn from toy materials in EN 71-3:2019 categories II (liquid or sticky materials) and III… (n=3) |
| 42 | EU 2020. Commission Regulation (EU) 2020/2081 amending REACH Annex XVII as regards substances in tattoo inks or permanent make-up, Official Journal of the European Union | 2020 | Government report | EU tHg, Ni, Sb, tAs, Cd, Cr-VI, Pb concentrations |
| 43 | Green Seal 2020. GS-51: Green Seal Standard for Laundry Care Products for Industrial and Institutional Use, Edition 1.6, Green Seal, Inc. voluntary environmental certification standard; Edition 1.6 issued April 8, 2020, replacing Edition 1.5 from September 12, 2019, with corrections/clarifications last made July 30, 2021. | 2020 | Regulatory standard | US Pb, tHg, Cd, Cr-VI, tAs, Co, Mn, Ni occurrence in Not applicable: this is the binding text of Green Seal GS-51 Edition 1.6 for industrial and institutional laundry… |
| 44 | New York State Department 2020. Cleansing Product Information Disclosure Program — Recommended Best Management Practices, New York State Department of Environmental Conservation (NY DEC) — undated post-court-ruling Recommended Best Management Practices (BMP) document supporting the statutory household-cleansing-product disclosure requirement at 6 NYCRR Part 659.6 (authorised by Environmental Conservation Law (ECL) Article 35). The predecessor Program Policy on Household Cleansing Product Information Disclosure was declared null and void by the NYS Supreme Court (Household & Commercial Products Association v. Seggos, ruling issued August 2020); DEC maintains the present BMP document as recommended practice while moving forward to implement the underlying statute and regulation. Document text references EPA’s pre-MCL drinking-water values for 1,4-dioxane (350 ppt) and PFOA/PFOS (70 ppt combined), consistent with pre-July-2020 publication of the BMP framework prior to NY DOH’s August 2020 adoption of stricter state MCLs for those chemicals. | 2020 | Government guidance | US-NY Pb, Cd, tAs, tHg, Cr-VI, Ni occurrence in Not applicable: post-2020 court-ruling Recommended Best Management Practices (BMP) guidance document. The 22-page document (sections A. Form of… |
| 45 | Hernandez et al. 2019. Cr(VI) and Cr(III) in milk, dairy and cereal products and dietary exposure assessment, Food Additives & Contaminants Part B: Surveillance | 2019 | Peer-reviewed | Cr-VI dietary exposure estimates in cheese |
| 46 | Bureau of Toxic Substance 2019. Technical Support Document for Derivation of Health-Based Guidance Values for Metals in Spices, New York State Department of Health | 2019 | Government report | US iAs, Cd, Cr-VI, Pb occurrence in Methodology document; no direct food-sampling data; uses FCID 2005-10 consumption data for children (0 to <7 years) and… |
| 47 | EU 2018. Commission Regulation (EU) 2018/1513 - REACH CMR restrictions in textiles, Official Journal of the European Union | 2018 | Government report | EU Cd, Cr-VI, tAs, Pb concentrations |
| 48 | Ren et al. 2018. One-Step and Nondestructive Reduction of Cr(VI) in Pork by High-Energy Electron Beam Irradiation, Journal of Food Science | 2018 | Peer-reviewed | CN Cr-VI, Cr occurrence in Laboratory experiment using lean, fat, and marbled pork purchased from a market in Hefei, China; pork tissues (2… |
| 49 | Piccinini et al. 2016. Safety of tattoos and permanent make-up. Final report, JRC Science for Policy report EUR 27947 EN, JRC101601; prepared for DG JUST under Administrative Arrangement N. 2014-33617 | 2016 | Government report | EU/CH/DE tAs, Ba, Cd, Co, Cr, Cr-VI, Cu, tHg, Ni, Pb, Se, Sb, Sn, Zn occurrence in JRC synthesis of RAPEX notifications and national tattoo/permanent-make-up ink surveillance: 126 RAPEX alerts for tattoo/PMU inks through 2015… |
| 50 | Suvarapu et al. 2016. Determination of heavy metals in the ambient atmosphere: A review, Toxicology and Industrial Health 33(1): 79–96 | 2016 | Review | CN/IN/KR Pb, Cd, tHg, MeHg, Cr, Cr-VI, tAs, Ni, Al, Cu, Zn, Mn, V, Co occurrence in Narrative review of approximately 70 quality research papers on heavy metal determination in ambient air (TSPM, PM10, PM2.5)… |
| 51 | Caterbow et al. 2016. Women and Chemicals: The impact of hazardous chemicals on women — A thought starter based on an experts’ workshop, Women in Europe for a Common Future (WECF) / Women International for a Common Future (WICF), in cooperation with UNEP (Geneva expert workshop 2014; publication completed mid-2015; ©2016 WECF) | 2016 | NGO report | global/EU/CN Pb, tHg, tAs, Cd, Cr-VI occurrence in Not applicable — scoping / policy review document, not a measurement study. The single embedded quantitative dataset reported… |
| 52 | EFSA 2014. Scientific Opinion on the risks to public health related to the presence of chromium in food and drinking water, EFSA Journal 2014;12(3):3595 | 2014 | Government report | EU Cr, Cr-VI occurrence in Analytical results submitted to EFSA on chromium in food (27,074) and drinking water (52,735) reported by EU Member… (n=79809) |
| 53 | EU 2014. Commission Regulation (EU) No 301/2014 of 25 March 2014 amending Annex XVII to Regulation (EC) No 1907/2006 as regards chromium VI compounds, Official Journal of the European Union L 90/1 | 2014 | Government report | EU Cr-VI concentrations |
| 54 | Stasinos et al. 2014. The Bioaccumulation and Physiological Effects of Heavy Metals in Carrots, Onions, and Potatoes and Dietary Implications for Cr and Ni: A Review, Journal of Food Science | 2014 | Review | GR/LV/US Pb, Cd, tAs, Cr, Cr-VI, Ni, Al, tHg, MeHg, Cu, Zn, Mn, Co occurrence in Narrative review compiling open-field and greenhouse studies of heavy-metal bioaccumulation in three root and tuber vegetables (Daucus carota,… |
| 55 | Stefaniak et al. 2014. Dissolution of the metal sensitizers Ni, Be, Cr in artificial sweat to improve estimates of dermal bioaccessibility, Environmental Science: Processes & Impacts 16: 341-351 | 2014 | Peer-reviewed | US Ni, Be, Cr, Cr-VI occurrence in Triplicate samples of three metal-sensitizer powders (beryllium metal, nickel metal, chromium carbide Cr3C2) extracted in artificial sweat (pH… (n=9) |
| 56 | EC 2013. Toy Safety Directive 2009/48/EC — An Explanatory Guidance Document (Rev 1.7), European Commission, Enterprise and Industry Directorate-General, Single Market for Goods; Rev 1.7, 13/12/2013 | 2013 | Government report | EU Al, Sb, tAs, Ba, B, Cd, Cr, Cr-VI, Co, Cu, Pb, Mn, tHg, Ni, Se, Sr, Sn occurrence in Regulatory guidance document interpreting EU Toy Safety Directive 2009/48/EC, including the 19-element migration-limit table at Annex II Part… |
| 57 | Centre for Food Safety 2012. Safety Issues of Baby Bottles and Children’s Tableware (Risk Assessment Studies Report No. 47), Centre for Food Safety, Food and Environmental Hygiene Department, Government of the Hong Kong Special Administrative Region. Risk Assessment Studies Report No. 47, January 2012 | 2012 | Government report | HK/EU/US Pb, Cd, Ni, Cr, Cr-VI, Al occurrence in Narrative literature review; no original measurements. The review summarises secondary toxicology and migration evidence from FAO/WHO, EFSA, USFDA,… |
| 58 | Johnson et al. 2012. Status Report: Review of Metals in the Toy Safety Standard, ASTM F 963, U.S. Consumer Product Safety Commission Status Report, Directorate for Health Sciences, 14 March 2012; bundles Versar/SRC final contractor report Contract CPSC-D-06-0006 Task Order 008 dated 16 July 2010 | 2012 | Regulatory | US/EU Sb, iAs, Ba, Cd, Cr, Cr-VI, Pb, iHg, Se occurrence in Regulatory status report, not a sampling study. The bundled Versar/SRC literature review covered ~13,000 references identified between 2000… |
| 59 | General Administration of Quality 2012. GB 28480-2012 饰品 有害元素限量的规定, National Standard of the People’s Republic of China | 2012 | Government report | CN Ni, tAs, Cr-VI, tHg, Pb, Cd, Sb, Cr-total concentrations |
| 60 | UL 2012. Chemicals in Children’s Toys: Addressing Stricter Limits and Environmental Concerns, UL LLC White Paper (UL Environment), 8 pp. | 2012 | Industry | US/EU Pb, Cd, tHg, Cr, Cr-VI, Ni, Al, Sb occurrence in No primary contamination measurements. UL LLC marketing white paper introducing UL 172, the voluntary UL Standard for Sustainability… |
| 61 | EU 2011. Directive 2011/65/EU on restriction of the use of certain hazardous substances in electrical and electronic equipment - consolidated version of 1 March 2023, Official Journal of the European Union / EUR-Lex consolidated text | 2011 | Government report | EU Pb, tHg, Cd, Cr-VI concentrations |
| 62 | Mahmud et al. 2011. Estimation of Chromium (VI) in various body parts of Local Chicken, Journal of the Chemical Society of Pakistan | 2011 | Peer-reviewed | PK Cr-VI occurrence in Local chicken parts (meat: sternum, leg, arm, gizzard, neck, heart, liver; bones: chest cage, neck, leg, head, arm)… |
| 63 | EU Scientific Committee on 2010. Evaluation of the Migration Limits for Chemical Elements in Toys (SCHER Opinion), European Commission DG Health & Consumers; SCHER Opinion adopted 1 July 2010 | 2010 | Government report | EU tAs, Cd, Cr-VI, Pb, tHg, Sn occurrence in Regulatory opinion evaluating EU Toys Safety Directive 2009/48/EC migration limits for 19 chemical elements |
| 64 | OEHHA 2008. Chromium (Hexavalent Compounds) — California Proposition 65 Chemical Listing, California Office of Environmental Health Hazard Assessment, Proposition 65 Listings | 2008 | Regulation | US-CA Cr-VI occurrence in Regulatory instrument. California Proposition 65 chemical listing for chromium (hexavalent compounds), with associated safe-harbor levels; applies to consumer… |
| 65 | OEHHA 2000. Appendix F - Dermal Uptake of Chemicals from Soil (Technical Support Document for Exposure Assessment and Stochastic Analysis), Cal/EPA OEHHA Air Toxics Hot Spots Program - Technical Support Document for Exposure Assessment and Stochastic Analysis | 2000 | Government report | US tAs, Cd, Pb, tHg, Ni, Cr-VI, Be occurrence in Regulatory guidance; per-chemical dermal absorption fraction (ABS) point estimates derived from review of in-vivo and in-vitro percutaneous-absorption studies… |
| 66 | Soares et al. 2000. Selective Determination of Chromium (VI) in Powdered Milk Infant Formulas by Electrothermal Atomization Atomic Absorption Spectrometry after Ion Exchange, Journal of AOAC International 83(1):220-223 | 2000 | Peer-reviewed | Cr-VI concentrations in infant formula (n=20) |
| 67 | European Chemical Industry Ecology 1992. Nickel, Cobalt and Chromium in Consumer Products: Allergic Contact Dermatitis, ECETOC Technical Report No. 45, Brussels, March 1992 (ISSN 0773-8072-45) | 1992 | Industry | EU/US/IL Ni, Co, Cr, Cr-VI occurrence in Literature-review compilation of nickel, cobalt and chromium concentrations measured in consumer products by 28 published studies (1956-1990) and… |
| 68 | IARC 1990. Chromium, Nickel and Welding, IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 49 | 1990 | Government report | INTL Cr, Cr-VI, Ni occurrence in International scientific working group; review of global occupational, environmental, dietary, and experimental data for Cr, Ni, and welding… |
Total-chromium sources that explicitly do not speciate Cr-VI
These are useful as total-chromium occurrence context only and should not be cited as Cr-VI evidence.
- Chuchu et al. 2013
- UK FSA 2016
- Chekri et al. 2019
- Chung et al. 2021
- Milani et al. 2023
- Meli et al. 2024
Update history
The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git. When DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.
| Commit | Date | Change | Description |
|---|---|---|---|
| a8052bb | 2026-08-09 | major | 8 sources added; contamination-profile values revised; 21 sections added |