Dried Herbs
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) | tier-unset | 8/10 HMTc analytes, total n=28 | consumption tier unset; depth bar uncheckable |
| D2 Regional coverage | OK | 10 jurisdictions, top PL 25% | — |
| D3 Anthropogenic evidence | GAP | 5 soil; no supply-chain link | link a supply-chain/ hub page |
| D4 Background mechanism | OK | section present, 4 drivers, 5 upstream source(s) | — |
| D5 Pooling depth | THIN | Pb THIN, Cd THIN, iAs THIN, tAs POOLABLE, tHg POOLABLE, Ni THIN, Al THIN, Cr THIN, Sn THIN | Pb: needs 3 distinct source(s); Cd: needs 3 distinct source(s); iAs: needs 2 more study(ies); Ni: needs 1 more study(ies); Al: needs 3 distinct source(s); Cr: needs 1 more study(ies); Sn: needs 2 more study(ies) |
| D6 Speciation | OK | iAs, tAs, tHg declared | — |
| D7 Basis declaration | GAP | 0/10 populated cells declare a basis token | 10 populated cell(s) lack a basis token: Pb, Cd, iAs, tAs, tHg, Ni, Al, Cr, Sn, U |
| D8 Provenance integrity | GAP | 5 claims checked, 5 supported; 8 citations, 0 orphan, 6 foreign | 6 foreign citation(s) not naming dried-herbs: angelon-gaetz2018-lead-spices-north-carolina, chime2025-nigerian-spices-as-cd-pb, cicero2022-minerals-spices-aromatic-herbs |
| D9 Mitigation | OK | 1 cited lever(s), 0 mitigation/ link(s) | — |
| D10 Regulatory coverage | GAP | 0 rule link(s), 0 metal(s) covered | no regulations/ link in section |
| D11 Standards-readiness | NOT-READY | priority: Pb, Cd, iAs, tAs, tHg, Ni, Al, Cr, Sn; pairing 0 paired, 9 single, 0 unpaired | Pb: THIN, needs 3 distinct source(s); Cd: THIN, needs 3 distinct source(s); iAs: THIN, needs 2 more study(ies); Ni: THIN, needs 1 more study(ies); Al: THIN, needs 3 distinct source(s); Cr: THIN, needs 1 more study(ies); Sn: THIN, needs 2 more study(ies); basis: 10 populated cell(s) lack a basis token: Pb, Cd, iAs, tAs, tHg, Ni, Al, Cr, Sn, U; consumption tier unset (depth bar uncheckable) |
| Principle balance | flag | consumer-protection 1.00, contamination-reduction 1.00, brand-value 0.50, legal-defensibility 0.25, scale 0.25 | spread 0.75 — starved: legal-defensibility |
Dried herbs — the dehydrated leaves, flowers, and aerial plant parts of culinary and medicinal aromatic plants (oregano, basil, thyme, parsley, sage, rosemary, mint, chamomile, lemon balm, dill, marjoram, savory) — share the drying-concentration heavy-metals pattern with the broader herbs-and-spices category. The dominant feature is concentration: fresh herbs at 80-90% moisture content dry down to product at 8-12% moisture, producing a 7-10× per-mass concentration uplift on Pb, Cd, and other metals relative to the fresh-weight baseline. The current corpus loads 3 routed sources plus broader herbs-and-spices corpus reachable via the routing layer: Angelon-Gaetz 2018 NC home-investigation cohort (n=386, angelon-gaetz2018-lead-spices-north-carolina), Chime 2025 Nigerian-market spice trace-metal work (n=7, chime2025-nigerian-spices-as-cd-pb), Cicero 2022 multi-origin 8-metal panel (n=13, cicero2022-minerals-spices-aromatic-herbs), Fischer 2022 Polish mercury in spice plants (n=48, fischer2022-mercury-spice-plants-poland), Huff 2025 Lancaster PA spice survey (n=116, huff2025-spices-lancaster-pa), Kowalska 2021 Polish 240-sample herb-spice-tea-coffee panel (kowalska2021-metals-herbs-spices-tea-coffee-poland), LHAAC 2025 Australian Coordinated Sampling Project 41 (n=380, lhaac2025-csp41-herbs-spices-wa), NYS DOH 2019 spice-specific health-based guidance values (nys-doh2019-metals-spices-guidance).
Why this commodity accumulates heavy metals
Dried herbs accumulate metals through two combined pathways: the live plant’s soil-uptake of Cd, Cr, Ni, and trace metals plus atmospheric deposition of Pb onto the leaf surface during the growing cycle, and the drying step that concentrates these metals on a per-mass basis by 7-10× through moisture removal. Drying is not contamination but a basis change; reporting consistency (dry weight vs fresh weight) matters when comparing values across sources. Atmospheric deposition is particularly relevant for herbs harvested in roadside or industrial-corridor settings, where surface Pb-and-Cd accumulate on the leaf during the growing cycle and then concentrate per-mass during drying. The Kowalska 2021 Polish dataset (n=240 across 37 herb species and 12 spice species) identified valerian root, lemon balm leaves, common sage, and chamomile flowers as higher-Pb species (kowalska2021-metals-herbs-spices-tea-coffee-poland). The Cicero 2022 multi-origin work (n=13 across IT, SA, IN, IR, ID, VN) provides the strongest within-non-adulterated baseline across the full 8-metal panel (cicero2022-minerals-spices-aromatic-herbs). The Australian Coordinated Sampling Project 41 (n=380 retail-and-import samples) is the largest single-jurisdiction recent dataset and demonstrates the population-scale per-species variance within commercial dried-herb product (lhaac2025-csp41-herbs-spices-wa). The Winiarska-Mieczan 2023 Polish n=432 herbs-and-single-component-spices Pb-Cd panel is referenced through the fresh-herbs page as a paired-product comparison.
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 | n=7 | 100–2000 | 5000 | high | 1, 2 |
| Cd | n=6 | 50–500 | 1200 | high | 1, 2 |
| iAs | n=1 | 10–200 | — | low | — |
| tAs | n=4 | 20–300 | — | medium | 1 |
| tHg | n=3 | 1–50 | — | medium | 1, 2 |
| Ni | n=2 | 200–3000 | — | low | — |
| Al | n=2 | 1000–20000 | — | low | — |
| Cr | n=2 | 50–1000 | — | low | — |
| Sn | n=1 | — | — | — | — |
| U | data gap | — | — | — | — |
Ranges by source, region, and variety
The corpus characterises dried herbs through both directly-routed studies and the broader herbs-and-spices corpus. The Polish Kowalska 2021 dataset is the most species-diverse with 37 herb species and 12 spice species, identifying within-species variance of 2-3 orders of magnitude across Pb and Cd (kowalska2021-metals-herbs-spices-tea-coffee-poland). The Australian LHAAC 2025 Coordinated Sampling Project 41 covers 380 retail-and-import samples with the 7-metal panel including Al specifically (lhaac2025-csp41-herbs-spices-wa). The North Carolina Angelon-Gaetz 2018 home-investigation cohort identified dried-herbs among the elevated-Pb spice samples in homes of children with elevated blood-lead levels (angelon-gaetz2018-lead-spices-north-carolina). The Lancaster PA Huff 2025 retail survey (n=116) included dried-herbs within the broader spice panel and reported the regulatory-gap analysis for the US market (huff2025-spices-lancaster-pa). The Polish Fischer 2022 mercury-in-spice-plants work (n=48) provides the strongest single-jurisdiction tHg data for the dried-herb category (fischer2022-mercury-spice-plants-poland). Within-species pattern: valerian root, lemon balm leaves, common sage, and chamomile flowers consistently sit at the higher end of the Pb distribution; thyme, oregano, basil, and rosemary at the middle; parsley, dill, and chives at the lower end. Country-of-origin matters: Mediterranean dried herbs (Italy, Greece, Spain, Turkey) sit at the lower-to-middle of the distribution; some South Asian and Middle Eastern origins carry higher loads driven by soil and atmospheric Pb.
Processing effects
Drying is the dominant processing-driven concentration event, with fresh-to-dried transitions concentrating metals on a per-mass basis by 7-10× through moisture removal. This is a basis change rather than contamination. Sun-drying, oven-drying, and freeze-drying produce similar per-mass concentration outcomes; freeze-drying preserves color and flavor better but does not differ on metal load. Grinding and blending introduce minor metal pickup from equipment surfaces. Steam sterilisation, irradiation, and ethylene-oxide-based microbial-control treatments do not affect metal load. The dried-herbs category does not have the adulteration risk that ground-spices (turmeric, paprika, cinnamon) face; the adulteration mechanism (lead chromate pigment addition) does not apply to the green-and-grey-colored dried-leaf products that dominate the dried-herb category.
Ingredient-derivative risk
Whole-leaf dried herbs (whole dried oregano, whole basil leaves, whole sage) carry the baseline dry-weight metal load. Ground dried herbs (ground oregano, ground thyme) carry the same per-mass load. Herbal-tea preparations (dried chamomile flowers, dried lemon balm, dried mint) inherit the dried-herb load; brewing extracts a partial fraction into the cup (see herbal-botanical-infusions for the prepared-infusion view). Herbal-tincture and herbal-supplement preparations concentrate the parent herb’s metal load proportional to extraction concentration; supplement-grade herbal product from non-audited supply chains can carry Pb-and-Cd at concentrations of regulatory concern. Italian-seasoning, herbes-de-Provence, and similar blends inherit the highest-load component’s metals weighted by the inclusion ratio.
Mitigation options
Sourcing levers
Species selection within the dried-herbs category shifts the per-mass Pb-and-Cd distribution. Sourcing thyme, oregano, basil, rosemary, and parsley over valerian root, lemon balm leaves, and chamomile flowers reduces the per-mass load for buyers without species-specific functional requirements. Origin-country sourcing matters: Mediterranean-origin product sits at the lower-to-middle of the distribution. Specify supplier transparency on the species mix in blended product.
Agronomic levers
For brand-controlled-supply operations, soil pH management around 6.5 and avoidance of phosphate fertilisers with elevated Cd impurity reduce upstream Cd loading. Avoid sourcing from roadside or industrial-corridor production. Most agronomic interventions live with herb producers.
Processing levers
Validate equipment surfaces in grinding and blending operations. The drying method (sun, oven, freeze-dry) does not meaningfully differ on metal load. Avoid extended storage in unsealed bulk bins where atmospheric Pb dust deposition can accumulate on surface.
Formulation levers
For herb-blend formulations, characterise the metal load of each ingredient input on a dry-weight basis and weight to keep aggregate Pb-and-Cd at the lowest achievable per-serving level. Dilution with lower-metal carrier ingredients reduces per-serving exposure proportionally.
Testing and QC levers
Lot-level ICP-MS testing of every dried-herb lot at intake, with detection floors ≤ 100 ppb Pb and ≤ 50 ppb Cd. The LHAAC 2025 protocol is a useful population-screening reference (lhaac2025-csp41-herbs-spices-wa).
Packaging and storage levers
Packaging is not the dominant pathway for dried herbs. Standard food-grade glass, plastic, or paperboard does not affect the metal load.
Regulatory limits that apply
The Codex Alimentarius General Standard CXS 193-1995 does not set a dried-herbs-specific maximum. The EU Regulation 2023/915 applies a 1.5 mg/kg Pb maximum for “dried herbs and spices” (a slightly different category than the broader “spices” maximum) and 0.5 mg/kg Cd for the same category. The NYS Department of Health 2019 Technical Support Document derived health-based guidance values (Pb 0.21, Cd 0.21, Cr 0.41, iAs 0.10 mg/kg) that apply to dried herbs as well as spices (nys-doh2019-metals-spices-guidance). FDA has issued occasional import alerts and enforcement actions on dried-herb product but does not maintain a category-specific action level.
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 | Saleem et al. 2025. Concentration and Potential Non-Carcinogenic and Carcinogenic Health Risk Assessment of Metals in Locally Grown Vegetables, Foods | 2025 | Peer-reviewed | US Cd, Pb, tAs, tHg, Cr, Ni, Co, Cu, Zn, Mn, Se occurrence in 82 samples of 13 locally grown vegetable types from the Town Square Farmer’s Market in Grand Forks, North… (n=82) |
| 2 | Winiarska-Mieczan et al. 2023. The Content of Cd and Pb in Herbs and Single-Component Spices Used in Polish Cuisine, Biological Trace Element Research | 2023 | Peer-reviewed | Cd and Pb in 100 dried-herb samples across 9 species from Polish retail, with dried form carrying highest Cd and Pb among herb forms |
| 3 | Fischer et al. 2022. The Mercury Concentration in Spice Plants, Processes | 2022 | Peer-reviewed | Polish mercury in 48 spice-and-herb plant samples; strongest tHg data |
| 4 | Gill et al. 2021. The Trouble With Spices: Heavy Metals in 15 Herbs and Spices, Consumer Reports | 2021 | NGO report | US Pb, Cd, tAs occurrence in 126 individual products covering 38 brands and 15 herb/spice types from the US retail market (n=126) |
| 5 | Kowalska 2021. The Safety Assessment of Toxic Metals in Commonly Used Herbs, Spices, Tea, and Coffee in Poland, International Journal of Environmental Research and Public Health | 2021 | Peer-reviewed | Polish 37-herb-12-spice (n=240) 4-metal panel; species-variance evidence |
| 6 | Liu et al. 2018. Speciation and bioaccessibility of arsenic in traditional Chinese medicines and assessment of its potential health risk, Science of the Total Environment | 2018 | Peer-reviewed | CN tAs, iAs occurrence in Twenty-four Chinese patent medicines and sixty Chinese herbal medicines purchased from a Beijing drugstore. The patent medicines included… (n=84) |
| 7 | Adams et al. 2017. Genotoxic studies of cooked and uncooked processed spices using Allium cepa Test, International Journal of Advanced Research in Biological Sciences | 2017 | Peer-reviewed | NG Pb, Cd, Cr, Ni occurrence in Market-sold curry, thyme, suya, and pepper-soup spices purchased in Ogun State, Nigeria (n=4) |
| 8 | Kočevar et al. 2017. Accumulation of heavy metals from soil in medicinal plants, Arhiv za higijenu rada i toksikologiju | 2017 | Peer-reviewed | SI/EU Pb, Cd, Zn, Cu, Fe, Mn occurrence in Above-ground parts of four medicinal plant species collected at eight Meža Valley locations in Slovenia, with paired topsoil… (n=32) |
| 9 | Mirosławski et al. 2017. Determination of the Cadmium, Chromium, Nickel, and Lead Ions Relays in Selected Polish Medicinal Plants and Their Infusion, Biological Trace Element Research | 2017 | Peer-reviewed | PL Cd, Cr, Ni, Pb occurrence in Five peppermint-leaf preparations and five chamomile-blossom preparations from Polish pharmacy retail, with three package-level samples per producer; all… (n=10) |
| 10 | Dghaim et al. 2015. Determination of Heavy Metals Concentration in Traditional Herbs Commonly Consumed in the United Arab Emirates, Journal of Environmental and Public Health | 2015 | Peer-reviewed | AE Pb, Cd, Cu, Fe, Zn occurrence in Seven traditional herbs (parsley n=13, basil n=11, sage n=11, oregano n=11, mint n=13, thyme n=13, chamomile n=9) purchased… (n=81) |
| 11 | Khan et al. 2013. Toxic and some essential metals in medicinal plants used in herbal medicines: A case study in Pakistan, African Journal of Pharmacy and Pharmacology | 2013 | Peer-reviewed | PK Pb, Ni, Cd, Cr occurrence in Eight medicinal plant species collected from two locations within a 20 km radius of Kallar Kahar Lake, Punjab,… (n=48) |
| 12 | Kulhari et al. 2013. Investigation of heavy metals in frequently utilized medicinal plants collected from environmentally diverse locations of north western India, SpringerPlus | 2013 | Peer-reviewed | IN Mn, Cr, Pb, Fe, Cd, Ni, Co, Zn, Hg occurrence in Stem and leaf samples from ten medicinal plant species collected from Haryana and Rajasthan, India, including Jhunjhunu, Churu,… (n=20) |
| 13 | Shah et al. 2013. Comparative Study of Heavy Metals in Soil and Selected Medicinal Plants, Journal of Chemistry | 2013 | Peer-reviewed | PK Fe, Ni, Mn, Zn, Cu, Cd, Cr, Pb occurrence in Leaves, stems, and roots of four medicinal plant species collected from polluted and unpolluted sampling points in District… (n=24) |
| 14 | Barthwal et al. 2008. Heavy Metal Accumulation in Medicinal Plants Collected from Environmentally Different Sites, Biomedical and Environmental Sciences | 2008 | Peer-reviewed | IN Pb, Cd, Cr, Ni occurrence in Five medicinal plant species collected from three Lucknow, India site types (heavy traffic area, residential area, industrial area),… (n=15) |
| 15 | Khan et al. 2007. Effect of Environmental Pollution on Heavy Metals Content of Withania somnifera, Journal of the Chinese Chemical Society | 2007 | Peer-reviewed | PK Cr, Pb, Cu, Cd, Fe, Ni, Mn occurrence in Withania somnifera roots, stems, leaves, and fruits, plus paired soils, collected from three locations of N.W.F.P./Peshawar Valley, Pakistan;… |
| 16 | Divrikli et al. 2006. Trace heavy metal contents of some spices and herbal plants from western Anatolia, Turkey, International Journal of Food Science and Technology | 2006 | Peer-reviewed | TR Cu, Cd, Pb, Ni, Cr, Fe, Mn, Zn occurrence in Eleven spice and herbal plant species collected from 50 farmers in western Anatolia, Turkey, June-October 2003; four samples… (n=44) |
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 |