Matcha
This page is HMTc Category 5 row 12 from the locked beverage architecture. It exists as a wiki node so evidence, regulatory context, ingredient routing, and future field findings have a stable place to land.
Heavy Metal Index pages are written for several audiences at once. Each entry point below names where to start if you are reading this page with a specific question in mind.
- Brand legal and regulatory affairs
- Cherry-pick attack vectors on matcha typically center on aluminum and lead, with concentrations elevated relative to steeped tea because the powdered leaf is consumed entire. Source-of-origin and grade (ceremonial vs culinary) are the defensive core. Compare with True Tea Camellia Sinensis for the within-pair sibling. The cited sources at the bottom of this page are the citations list, written to be quoted into a Daubert brief without further editing.
- Retailer quality and compliance
- The Federal / Regulatory Limits vs Field Findings section compares the applicable regulatory cap to cited field evidence on a like-for-like basis, with basis conversion shown when conversion is well-defined and a methodology anchor when speciation differs. The Literature Evidence Summary gives source count and confidence rating per analyte.
- Brand QA and product development
- Use the Lab Result Comparator to position a single lab value inside the cited literature. The comparator positions a single lab value inside the cited literature for matcha, with leaf-consumption context for aluminum and lead.
- Regulators, journalists, and adversarial readers
- Every numeric claim on this page traces to a source page. The Evidence Governance note explains what this page is and is not (literature evidence, not HMT&C certification thresholds).
- HMT&C staff (internal)
- HMT&C certification thresholds for products in this row are developed under the certification program at heavymetaltested.com, not on this public page. The Index and HMT&C operate on the same evidence base but apply different publication rules; see the methodology for the separation.
| Field | Status |
|---|---|
| Row state | Locked row node; structured occurrence extraction pending |
| Category hub | category-5-beverages |
| Crosswalk hub | regulatory-crosswalk-field-findings |
| HMTc use | Routing and evidence-gap tracking only; not a certification threshold |
Federal / Regulatory Limits vs Field Findings
This is the fast comparison view for standards developers, regulators, retailers, brands, and legal teams. It shows the applicable federal or regulatory limit next to the current field-evidence state. It is not an HMTc pass/fail table; technical distributions remain in the evidence sections below.
| Metal | Federal / regulatory limit | Actual field finding | Decision read | Evidence |
|---|---|---|---|---|
| No loaded row | No federal or product-specific regulatory limit loaded yet | Comparable field finding extraction pending | Evidence-gap tracking only; do not infer a pass/fail status | regulatory-crosswalk-field-findings |
Evidence Handling
Finished-product findings belong on this product page. Ingredient-only findings belong on ingredient pages before they are used for product inference.
Literature Evidence Summary
The table below summarizes what the peer-reviewed and government literature cited on this page reports for heavy-metal concentrations in Matcha. Values are pulled directly from cited sources without re-aggregation; pooling, percentile selection, and threshold math sit in the staff Standards Workbench rather than this public page.
Methodology rules for speciation, basis preservation, non-detect handling, and source pooling are stated in the Methodology section above and apply to every row below.
| Analyte | Subcategory | Reported concentration range | Detection rate | Applicable regulatory cap | Sources | Confidence | Basis |
|---|---|---|---|---|---|---|---|
| Al | Matcha (no contributing evidence loaded) | No concentration data loaded for this analyte | Sample-level detection rate not reported | No applicable cap loaded | 0 | data gap | Basis not reported |
| Pb | Matcha (no contributing evidence loaded) | No concentration data loaded for this analyte | Sample-level detection rate not reported | No applicable cap loaded | 0 | data gap | Basis not reported |
| Cd | Matcha (no contributing evidence loaded) | No concentration data loaded for this analyte | Sample-level detection rate not reported | No applicable cap loaded | 0 | data gap | Basis not reported |
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 | Szymczykowska et al. 2026. Elemental Composition of Japanese Matcha Powder and Infusions—Potential Role as a Functional Food in Metabolic Health, Beverages | 2026 | Peer-reviewed | JP/PL Pb, Cr, Ni occurrence in Two Japanese organic matcha types (daily matcha and traditional matcha) from Uji region, Kyoto, Japan; two batches each,… (n=2) |
| 2 | Masri et al. 2025. Assessing Dietary Consumption of Toxicant-Laden Foods and Beverages by Age and Ethnicity in California: Implications for Proposition 65, Nutrients | 2025 | Peer-reviewed | US Pb, Cd, tAs, MeHg occurrence in Cross-sectional online dietary survey (Qualtrics) administered between 1 March and 15 June 2023 to Southern California residents (adults… (n=186) |
Who this page is for
This page is for readers who need matcha treated as its own exposure pathway rather than as ordinary steeped tea. Brand legal and QA teams should focus on the distinction between powder-as-consumed and infusion-only evidence: matcha suspends the whole leaf powder, so powder-basis Pb, total Cr, and Ni findings can matter even when brewed-tea data look modest. Retailers and regulators should use the page as a literature map, not as a pass/fail table, because the current source base is one small organic Japanese sample set and contains paper-internal tensions for powder Pb and Cr that need supplementary-table confirmation before quantitative pooling.
Methodology
Matcha evidence is handled on the basis the source reports. Powder values stay powder-basis because the product is consumed as suspended whole leaf; infusion values stay beverage-basis and are useful for preparation context but cannot substitute for powder exposure when the dry powder is ingested. Chromium values from the current source are total Cr only, not Cr(VI), and the page does not infer Cd, arsenic, mercury, aluminum, tin, antimony, or uranium from a source that did not measure them. Figure-derived values are treated as provisional anchors when the paper does not print supplementary-table numbers in the main text.
Source Evidence Inventory
szymczykowska2026-matcha-elemental-composition is the current matcha-specific occurrence source. It measured two organic Uji-region Japanese matcha products, daily matcha and traditional matcha, as both powder and infusions prepared at 25, 70, 80, and 90 C. The source reports Pb, total Cr, and Ni among the Heavy Metal Index analytes. It does not measure Cd, arsenic species, mercury species, Al, Sn, Sb, or U, so those cells remain gaps.
The source is especially useful for basis discipline. The powder results are the closest exposure basis for matcha-as-consumed, while the infusion results show the soluble fraction and the lack of a statistically significant brewing-temperature effect. Two paper-internal issues are carried forward as cautions: Figure 4 appears to show traditional-matcha powder Pb above the plant-product range the authors cite as safe, and Figure 4 powder Cr appears roughly 20 times higher than the authors’ intake-percentage statement would imply.
Broad Product Context: Author-Scope Index
Pending: regenerated by tools/evidence/apply-product-broad-context.mjs once broad-scope sources route to this page.
Levers to reduce contamination
Current evidence supports three practical levers. First, test matcha powder directly rather than relying on brewed-tea infusion data, because matcha consumers ingest the suspended leaf powder. Second, preserve origin, harvest, and grade metadata in sampling plans; the current source studied only two organic products from one Uji-region producer, so broader market claims need wider sourcing coverage. Third, include Pb, total Cr with speciation caveat, Ni, Cd, inorganic arsenic, total arsenic, mercury species, and Al in QA panels, because the current matcha-specific source covers only Pb, total Cr, and Ni and leaves several known tea-leaf concern analytes unmeasured.
How standards math uses this page
The percentile arithmetic that informs HMTc thresholds for this product category lives on the staff Standards Workbench (data/workbench/standards/<this-slug>.md). This public page reports literature evidence; the workbench applies the methodology in CLAUDE.md Part 19. The gap between literature evidence and HMTc thresholds is named honestly on the workbench, not hidden.
Historical recalls and enforcement
No matcha-specific recall or enforcement source is currently routed to this page. Until public-record regulatory events are ingested, this section should remain a gap rather than borrowing enforcement history from broader tea categories.
Page history
The five most recent substantive edits to this page. 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 | Description |
|---|---|---|
| b0f3d38 | 2026-06-12 | batch | corpus rescreen b04 old terminal skips |