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Fresh 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.

DimensionStatusWhat’s there (auditable counts)What’s missing
D1 Analyte coverage (tier: unset)tier-unset6/10 HMTc analytes, total n=12consumption tier unset; depth bar uncheckable
D2 Regional coverageOK4 jurisdictions, top IR 50%
D3 Anthropogenic evidenceGAP1 agricultural-soil + 1 irrigation-water; no supply-chain linklink a supply-chain/ hub page
D4 Background mechanismOKsection present, 4 drivers, 1 upstream source(s)
D5 Pooling depthTHINPb CONFIDENT, Cd CONFIDENT, tAs THIN, tHg THIN, Ni THIN, Al THIN, Cr THINtAs: needs 2 more study(ies); tHg: needs 1 more study(ies); Ni: needs 2 more study(ies); Al: needs 2 more study(ies); Cr: needs 2 more study(ies)
D6 SpeciationOKiAs, tAs, tHg declared
D7 Basis declarationGAP0/10 populated cells declare a basis token10 populated cell(s) lack a basis token: Pb, Cd, iAs, tAs, tHg, Ni, Al, Cr, Sn, U
D8 Provenance integrityGAP6 claims checked, 6 supported; 3 citations, 0 orphan, 1 foreign1 foreign citation(s) not naming fresh-herbs: lhaac2025-csp41-herbs-spices-wa
D9 MitigationGAP0 cited lever(s), 0 mitigation/ link(s)section present but no source-cited lever
D10 Regulatory coverageGAP0 rule link(s), 0 metal(s) coveredno regulations/ link in section
D11 Standards-readinessNOT-READYpriority: Pb, Cd, tAs, tHg, Ni, Al, Cr; pairing 0 paired, 7 single, 0 unpairedtAs: THIN, needs 2 more study(ies); tHg: THIN, needs 1 more study(ies); Ni: THIN, needs 2 more study(ies); Al: THIN, needs 2 more study(ies); Cr: 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 balanceflagconsumer-protection 1.00, contamination-reduction 0.00, brand-value 0.50, legal-defensibility 0.25, scale 0.25spread 1.00 — starved: contamination-reduction

Fresh herbs — the live or freshly-cut leaves, flowers, and aerial plant parts of culinary aromatic plants (basil, parsley, cilantro, dill, mint, thyme, oregano, sage, rosemary, chives, tarragon, marjoram) — sit at the lower end of the herbs-and-spices category by per-mass concentration because the fresh form has not undergone the 7-10× concentration uplift that drying produces. Fresh herbs are commonly grown in home gardens, community gardens, urban allotments, and small-scale commercial production, which means siting variability (roadside, industrial-corridor) drives much of the within-category variance on Pb specifically. The current corpus loads 3 directly-routed sources: Fischer 2022 Polish mercury in spice plants (n=48 including fresh-leaf samples, fischer2022-mercury-spice-plants-poland), LHAAC 2025 Australian Coordinated Sampling Project 41 covering both fresh and dried product (n=380, lhaac2025-csp41-herbs-spices-wa), and Winiarska-Mieczan 2023 Polish Cd-Pb in 432 herb-and-single-component-spice samples covering fresh herbs as a subset (winiarska-mieczan2023-cd-pb-polish-herbs-spices). The paired-product comparison with dried-herbs establishes the fresh-vs-dried-basis factor; the same plant species at the same source carries roughly 1/8 to 1/10 the per-mass Pb-and-Cd of the dried form purely from the moisture-removal accounting.

Why this commodity accumulates heavy metals

Fresh herbs take metals through the same plant-physiology pathways as the broader leafy-vegetable category (see leafy-vegetables): root uptake of soluble soil metals (Cd, Cr, Ni) via the transpiration stream, and direct atmospheric deposition of particulate Pb onto the leaf surface during the growing cycle. The surface-area-to-volume ratio of fresh-herb leaves (typically thin, large surface area per gram) makes them efficient collectors of atmospheric Pb relative to root vegetables or compact-head leafy vegetables. The siting of fresh-herb production is highly variable: commercial Mediterranean herb production (Italy, Greece, Spain, Turkey) is dominantly in cropland settings with managed soil and water; home-garden and urban-garden production often sits in settings with elevated soil or atmospheric Pb backgrounds (former industrial sites, roadside plots). The Polish Winiarska-Mieczan 2023 dataset (n=432 herbs and single-component spices) is the largest single-jurisdiction recent dataset for the Cd-and-Pb profile across fresh and dried product on a comparable methodological basis (winiarska-mieczan2023-cd-pb-polish-herbs-spices). The Fischer 2022 Polish mercury-in-spice-plants work characterises the mercury profile across 48 fresh-leaf samples, finding generally low mercury but with detectable concentrations in some species (fischer2022-mercury-spice-plants-poland). The Australian LHAAC 2025 CSP 41 covers both fresh and dried product at scale (n=380) with the 7-metal panel (lhaac2025-csp41-herbs-spices-wa).

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.

AnalyteCoverageTypical (ppb)p95 (ppb)ConfidenceKey sources
Pbn=310–300800high1
Cdn=35–80200high1
iAsdata gap
tAsn=15–50low
tHgn=20–10medium1
Nin=1
Aln=1
Crn=1
Sndata gap
Udata gap

Ranges by source, region, and variety

The Polish Winiarska-Mieczan 2023 dataset (n=432) is the most species-diverse fresh-herbs dataset in the loaded corpus, covering common Polish-cuisine herbs and single-component spices in their fresh and dried forms; the work confirms the fresh-vs-dried-basis factor of ~7-10× concentration on a per-mass basis (winiarska-mieczan2023-cd-pb-polish-herbs-spices). The Australian LHAAC 2025 CSP 41 covers both fresh and dried product across n=380 retail-and-import samples with the 7-metal panel (lhaac2025-csp41-herbs-spices-wa). The Fischer 2022 Polish mercury-in-spice-plants work (n=48 fresh-leaf samples) is the most species-specific tHg data for fresh herbs (fischer2022-mercury-spice-plants-poland). Species-level variance is substantial: parsley, dill, chives, and basil sit at the lower end of the fresh-herb Pb-and-Cd distribution; sage, lemon balm, and chamomile sit at the higher end (mirroring the dried-herb pattern); thyme, oregano, mint sit at the middle. Siting matters more than species for the Pb pathway specifically: roadside-grown parsley can carry more Pb than commercially-grown lemon balm grown on Mediterranean cropland away from atmospheric sources.

Processing effects

Drying is the major processing transition for fresh herbs, with fresh-to-dried producing the 7-10× per-mass concentration uplift documented above. The transition is well-characterised and is a basis change rather than contamination. Washing fresh herbs before consumption removes surface particulate Pb (the atmospheric-deposition fraction) but does not affect internalised Cd, Cr, or Ni. Blanching and freezing (used for some processed fresh-herb products) loses small fractions of soluble Cd and Cr to the blanch water. Chopping and mincing do not affect the per-mass metal load. Herb purees and pestos concentrate the per-mass metal load proportional to the moisture-removal during processing.

Ingredient-derivative risk

Fresh whole-leaf herbs represent the baseline. Bagged or packaged fresh-herb product carries the same per-mass load with surface contamination reduced. Frozen herbs lose a small fraction of soluble metals to the freezing-and-blanching step. Herb pestos (basil pesto, parsley pesto, cilantro chutney) concentrate metals on a per-mass basis through moisture removal. Herb-infused oils carry a much smaller fraction of the parent herb’s metal load because most metals partition with the solid residue rather than the oil phase. Herb-infused vinegars and herb teas extract a fraction of the parent herb’s soluble metals into the liquid; per-serving exposure tracks the herb mass and the extraction efficiency.

Mitigation options

Sourcing levers

Source from production regions and operations with documented soil-and-water screening, away from roadsides and industrial corridors. For home-gardeners and urban-gardeners, soil testing before planting is the upstream intervention. Specify commercially-grown Mediterranean-origin product for the lower-end of the distribution.

Agronomic levers

Soil pH management around 6.5 reduces Cd bioavailability. Avoidance of phosphate fertilisers with elevated Cd impurity reduces Cd loading. For brand-controlled-supply operations, raised-bed and container-growing with imported clean substrate eliminates the inherited-soil Pb pathway.

Processing levers

Washing reduces surface Pb but not internalised metals. Drying concentrates metals on a per-mass basis (basis change, not contamination). Avoid extended storage in unsealed bulk where atmospheric Pb dust deposition can accumulate.

Formulation levers

For finished-product applications using fresh herbs as one ingredient, the inclusion ratio caps per-serving exposure. Substitution between fresh-herb species shifts the per-mass profile modestly.

Testing and QC levers

Lot-level ICP-MS testing for Pb (detection floor ≤ 10 ppb fresh-weight) and Cd (≤ 5 ppb fresh-weight) is appropriate for commercial fresh-herb buyers, with conversion to dry-weight equivalent reporting where the downstream product is dried.

Packaging and storage levers

Packaging is not the dominant pathway for fresh herbs. Standard food-grade clamshell and bag packaging do not affect the metal load.

Regulatory limits that apply

The Codex Alimentarius General Standard CXS 193-1995 applies the leafy-vegetable Pb maximum of 0.30 mg/kg fresh weight to fresh herbs, and Cd at 0.20 mg/kg fresh weight (general vegetables; some fresh herbs fall under specific tighter categories). The EU Regulation 2023/915 applies tighter limits: 0.30 mg/kg Pb for “leafy vegetables and fresh herbs,” and 0.20 mg/kg Cd for leafy vegetables and stems excluding celery and salsify. The Australian LHAAC 2025 CSP 41 found commercial fresh-herb product generally compliant with applicable Australian caps on a fresh-weight basis (lhaac2025-csp41-herbs-spices-wa). The Polish Winiarska-Mieczan 2023 work confirmed similar compliance for the Polish-market fresh-herb category (winiarska-mieczan2023-cd-pb-polish-herbs-spices).

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]*.

#CitationYearTypeUsed on this page for
1Winiarska-Mieczan et al. 2023. The Content of Cd and Pb in Herbs and Single-Component Spices Used in Polish Cuisine, Biological Trace Element Research2023Peer-reviewedPolish fresh-and-dried herb Cd-Pb panel (n=432); largest single-jurisdiction dataset establishing fresh-vs-dried-basis factor
2Fischer et al. 2022. The Mercury Concentration in Spice Plants, Processes2022Peer-reviewedPolish mercury in 48 fresh-leaf spice-plant samples; strongest tHg data
3Souri et al. 2019. Plant growth stage influences heavy metal accumulation in leafy vegetables of garden cress and sweet basil, Chemical and Biological Technologies in Agriculture2019Peer-reviewedIR Cd, Pb, Ni, tAs, Cr, Co, Cu, Mn, Zn occurrence in Garden cress and sweet basil from five wastewater-irrigated farms in Shahre Rey, south of Tehran, Iran; field samples… (n=5)
4Ghasemidehkordi et al. 2018. Concentration of lead and mercury in collected vegetables and herbs from Markazi province, Iran: a non-carcinogenic risk assessment, Food and Chemical Toxicology 113:204-2102018Peer-reviewedIR Pb, tHg occurrence in Ten species of green leafy vegetables and herbs (Allium ampeloprasum L. [leek], A. wakegi L. [Welsh/Japanese bunching onion],… (n=160)
5Salehipour et al. 2015. Health Risks from Heavy Metals via Consumption of Cereals and Vegetables in Isfahan Province, Iran, Human and Ecological Risk Assessment: An International Journal2015Peer-reviewedIR Pb, tAs, Ni, Zn, Cu occurrence in Seventy edible-part samples of nine commodities — onion (Allium cepa), leek (Allium pp.; species not stated by authors),… (n=70)
6Kazimov et al. 2014. Examination and Hygienic Assessment of Health Risk Depending on Heavy Metals Content in Foods, Kazanskiy Meditsinskiy Zhurnal (Kazan Medical Journal), vol. 95, no. 5, pp. 706–7092014Peer-reviewedAZ Pb, Cd, Cr, Ni, Cu, Zn occurrence in 57 adults (28 men, 29 women, age 19–49) sampled by random selection from Baku, Azerbaijan; 18 food items… (n=57)

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.

CommitDateDescription
b0f3d382026-06-12batch | corpus rescreen b04 old terminal skips