Matcha powder
Completeness scorecard
Deterministic gap audit — no score is composite, no cell is LLM-judged. Each chip is re-derivable by re-running tools/evidence/build-ingredient-scorecard.mjs. review: residuals and missing data are worked autonomously via data/evidence/ingredient-scorecard-review-flags.csv and wiki/completeness-gaps.md.
| Dimension | Status | What’s there (auditable counts) | What’s missing |
|---|---|---|---|
| D1 Analyte coverage (tier: unset) | GAP | 0/10 HMTc analytes, total n=0 | only 0/10 analytes have evidence |
| D2 Regional coverage | OK | 3 jurisdictions, top US 50% | — |
| D3 Anthropogenic evidence | GAP | no upstream/attribution sources | link a supply-chain/ hub page |
| D4 Background mechanism | GAP | section present, 0 drivers, 0 upstream source(s) | drivers[] empty; no upstream source to substantiate |
| D5 Pooling depth | GAP | no priority analytes | — |
| D6 Speciation | OK | iAs, tHg, tAs declared | — |
| D7 Basis declaration | GAP | 0/10 populated cells declare a basis token | 10 populated cell(s) lack a basis token: Pb, Cd, iAs, tHg, Ni, Al, Cr, Sn, tAs, U |
| D8 Provenance integrity | OK | 2 claims checked, 2 supported; 1 citations, 0 orphan, 0 foreign | — |
| D9 Mitigation | GAP | 0 cited lever(s), 6 mitigation/ link(s) | section present but no source-cited lever |
| D10 Regulatory coverage | OK | 2 rule link(s), 0 metal(s) covered | — |
| D11 Standards-readiness | NOT-READY | no priority analytes | basis: 10 populated cell(s) lack a basis token: Pb, Cd, iAs, tHg, Ni, Al, Cr, Sn, tAs, U; consumption tier unset (depth bar uncheckable) |
| Principle balance | flag | consumer-protection 0.67, contamination-reduction 0.00, brand-value 0.00, legal-defensibility 0.75, scale 0.00 | spread 0.75 — starved: contamination-reduction |
This is a structural ingredient node created so product pages can link to a real wiki target. Occurrence values remain pending until a source is promoted for this ingredient.
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.
| Analyte | Coverage | Typical (ppb) | p95 (ppb) | Confidence | Key sources |
|---|---|---|---|---|---|
| Pb | data gap | — | — | — | — |
| Cd | data gap | — | — | — | — |
| iAs | data gap | — | — | — | — |
| tAs | data gap | — | — | — | — |
| tHg | data gap | — | — | — | — |
| Ni | data gap | — | — | — | — |
| Al | data gap | — | — | — | — |
| Cr | data gap | — | — | — | — |
| Sn | data gap | — | — | — | — |
| U | data gap | — | — | — | — |
Routing
This node is linked from matcha.
Contamination Profile State
The machine-readable contamination profile is pending. Ingredient-level values belong here once parsed; finished-product values belong on the relevant product-category page.
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) |
Why this commodity accumulates heavy metals
Matcha is shade-grown tencha-grade Camellia sinensis leaf, stone-ground to a fine powder consumed whole (not infused and strained). The plant-physiological aluminum-accumulator behavior of camellia sinensis (camellia-sinensis) applies in full to matcha, but the exposure pathway is fundamentally different from brewed tea: the consumer ingests the entire leaf material rather than a fraction of metals extracted into a brew. Matcha therefore delivers the full per-leaf metal load per serving, not the brew-extracted fraction.
The HMTc panel concerns for matcha are dominantly Al (the plant-physiological accumulator delivered at full leaf concentration), with secondary Cd, Pb, and Cr. Per-serving Al exposure from matcha is multiple times higher than per-serving Al from brewed tea at equivalent serving volume.
Ranges by source, region, and variety
Matcha is overwhelmingly produced in Japan (Uji, Nishio, Yame, and Shizuoka regions are the principal production areas), with smaller production in China and emerging production in Taiwan and Korea. Within Japanese matcha, ceremonial-grade matcha (made from the youngest top-leaf picks of the spring harvest) carries less Al per gram than culinary-grade matcha (made from later picks and more mature leaves). The matcha grades — ceremonial, premium ceremonial, classic, culinary, ingredient — differ in Al content roughly inversely to grade tier, mirroring the camellia sinensis leaf-age pattern.
Production-region differences exist among Japanese matcha origins; per-region Al variance is documented in Szymczykowska 2026 which characterized matcha elemental composition from multiple production regions. Chinese matcha-style products carry distinct soil-region profiles from Japanese matcha and have been documented at higher per-gram Pb in some surveys.
The “matcha-style green tea powder” market includes substantial product variation that conflates true Japanese tencha-derived matcha with cheaper green-tea-powder products. The per-product metal profile depends on the actual source material; “matcha latte mix” products may be a blend of matcha and other powdered ingredients.
Processing effects
Matcha processing is distinct from other tea processing in that the leaf is not steeped and strained. The traditional process:
- Shade-grown (kabuse-cha or tencha cultivation): the plant is shaded for 3-4 weeks before harvest, which increases chlorophyll and theanine while reducing some sun-photosynthesis byproducts. The shading does not substantially change metal-accumulation.
- Steaming to halt oxidation immediately after harvest. No metal effect.
- De-veining and de-stemming to separate the leaf-blade from harder structures, producing tencha-grade leaf. Some of the harder leaf structures carry slightly different metal profiles; the de-veining step reduces fiber but doesn’t substantially shift Al.
- Stone-grinding at low temperature in granite mills. The grinding step is the operational specification that distinguishes true matcha from green tea powder: stone-ground matcha is fine enough to suspend in water rather than precipitate. Grinding-equipment metal contact (granite vs steel) affects trace metal contamination; traditional granite stone mills avoid the steel-grinder Cr and Pb contamination pathway.
The consumer preparation step — whisking matcha powder into hot water and drinking the suspension — delivers 100 percent of the powder’s metal content to the consumer. There is no leaching-and-discard step that reduces exposure.
Ingredient-derivative risk
Matcha-flavored products (matcha lattes, matcha ice cream, matcha chocolate, matcha pastries) inherit matcha’s metal load proportional to the matcha fraction in the recipe. A typical matcha latte made with 2 grams matcha delivers approximately the same Al as ingesting 2 grams of matcha directly; the latte’s milk content does not change the matcha-portion metal load.
Matcha dietary supplements (capsules and tablets) deliver the full per-serving leaf-metal content and route to Cat 16 row 15 when sold with Supplement Facts labels.
Mitigation options
Sourcing levers (supply-chain-screening) are the dominant intervention. Choosing Japanese matcha from documented low-Pb production regions and ceremonial-grade matcha (youngest leaves, lowest Al) reduces per-serving exposure. Single-origin sourcing with per-lot Al, Cd, Pb testing is the operational specification for high-quality matcha brands.
Agronomic levers (agronomic) operate at the tea-farm level (shading practices, soil-amendment Al management, cultivar selection within tencha varieties). The aluminum-accumulator mechanism is plant-physiological and not eliminable via agronomic intervention; agronomic levers can shift Al modestly but not order-of-magnitude.
Processing levers (processing) include grinding-equipment specification (granite mills over steel grinders avoid grinding-Cr contamination) and tencha-leaf selection (de-veining and de-stemming yield slightly different metal profiles than whole-leaf grinding).
Formulation levers (formulation) for matcha-containing products include matcha-percentage adjustment in mixed products (a 1 percent matcha sprinkle in a baked good delivers far less per-serving Al than a 2-gram matcha latte) and species substitution (using a non-Camellia-sinensis green powder, such as moringa or wheatgrass, which have different metal profiles).
Testing and QC levers (testing-and-qc) include lot-level Al testing as a primary specification, with Cd and Pb testing secondary. Detection floors well below per-serving exposure equivalents of the JECFA/EFSA Al TWI guide brand-side procurement decisions. See icp-ms.
Packaging and storage levers (packaging-and-storage) are not consequential for matcha metal load. Matcha is light- and oxygen-sensitive for flavor and color reasons (not metal-content reasons); appropriate packaging is a quality-not-safety concern.
Regulatory limits that apply
- eu-2023-915 — EU Reg. 2023/915 does not currently set a matcha-specific maximum level. The general tea Pb ML applies to dry matcha powder.
- Codex Alimentarius does not maintain a matcha-specific ML.
- FDA does not maintain a binding action level for Al, Cd, or Pb in matcha specifically.
- JECFA Provisional Tolerable Weekly Intake for aluminum (2 mg/kg b.w./week) and EFSA TWI (1 mg/kg b.w./week) anchor the dose-response framing. A daily 2-gram matcha serving can deliver 2-10 mg Al per day depending on the per-gram matcha Al level, which can push heavy daily matcha consumers above the EFSA TWI on a body-weight basis. Brand-side product labeling for daily-use matcha products at the upper end of the Al range warrants serving-size guidance.
- California Prop 65 (california-prop65) Pb MADL applies to matcha sold in California; the serving-based screen governs.
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 |