Kočevar Glavač et al. 2017 - soil-to-medicinal-plant metals in Slovenia

Kočevar Glavač and coauthors measured Cd, Pb, Zn, Cu, Fe, and Mn in four wild medicinal plant species and paired soil samples from eight locations in Slovenia’s Meža Valley, including sites near a former lead smelter. The plant occurrence data are directly relevant to herbal-botanical raw material; the soil data are supply-chain context rather than product concentrations. The paper also reports hot-water extraction from Urtica dioica at two locations, giving a prepared-infusion view separate from the dried plant table.

Key numbers

All Table 1, Table 3, Table 4, and Table 5 values below preserve the source units (mg kg-1 or percent) and are not converted. Soil values are included only as growing-site context; plant and hot-water-extract values are the routeable occurrence data.

Plant concentrations

Table 3 reports plant concentrations in mg kg-1 for above-ground plant parts. Source-highlighted cells above the European Commission plant limits are not re-marked here; the printed EC limit row is Cd 1.0 mg kg-1 and Pb 5.0 mg kg-1.

Range summary from Table 3: Urtica dioica Cd 0.2-0.9, Pb 1.1-15.5, Zn 29.1-73.5, Cu 5.0-18.7, Fe 77.1-190.4, Mn 14.9-318.0 mg kg-1; Hypericum perforatum Cd 0.2-4.2, Pb 2.1-25.1, Zn 26.9-103.4, Cu 6.3-11.7, Fe 32.2-115.0, Mn 7.8-75.4 mg kg-1; Achillea millefolium Cd 0.3-5.7, Pb 1.5-15.9, Zn 23.2-211.7, Cu 4.2-9.9, Fe 47.8-145.5, Mn 16.6-163.2 mg kg-1; Plantago lanceolata Cd 0.3-16.0, Pb 1.4-195.9, Zn 33.3-799.5, Cu 4.2-10.2, Fe 58.5-338.7, Mn 10.3-75.4 mg kg-1.

Soil context

Table 1 reports paired soil concentrations in mg kg-1. These figures document growing-site contamination and are not product occurrence values.

The authors state that the highest soil Cd, Pb, and Zn levels exceeded Slovenian limit values 75-fold, 49-fold, and 14-fold, respectively, and exceeded critical limits 6-fold, 8-fold, and 4-fold, respectively.

Bioconcentration and hot-water extraction

Table 4 reports average bioconcentration factors across eight locations. Cd was the highest-accumulating metal across all species (all-species factor 0.46±0.62), while Pb had an all-species factor of 0.03±0.04. Plantago had the highest all-metals factor (0.22±0.34), and Urtica had the lowest all-metals factor (0.13±0.16).

Table 5 reports hot-water extraction from Urtica dioica as mg kg-1 expressed per kg herbal drug, n=3: Topolščica Cd 0.05, Pb below LOD, Zn 14.39, Cu 1.64, Fe 7.51, Mn 26.20; Žerjav 1 Cd 0.06, Pb below LOD, Zn 34.56, Cu 1.79, Fe 9.96, Mn below LOD. In the Results text, the authors describe the same Cd comparison as 0.053 versus 0.063 mg kg-1 and state extraction rates of 7-22% for Cd, 47-48% for Zn, 18-19% for Cu, 4-13% for Fe, and 8% for Mn.

Methods (brief)

Soil and plant samples were collected in June 2014 from eight Meža Valley locations, including three Žerjav sites near a former smelter and five surrounding locations. Above-ground parts of Achillea millefolium, Hypericum perforatum, Plantago lanceolata, and Urtica dioica were collected as three plants per species-location, 1 to 3 m apart, then air-dried for seven days and ground. Soil samples were taken at 5 to 10 cm depth, air-dried, ground, and passed through a 2-mm sieve. Plant digestion used 0.5 g sample additionally dried at 80 °C for 12 hours with 7.0 mL HNO3 and 2.0 mL H2O2 in closed-vessel high-pressure microwave digestion; soil digestion used 0.5 g with 9.0 mL HCl and 3.0 mL HNO3. Cd and Pb were measured by Perkin Elmer AAnalyst 600 graphite-furnace AAS with HGA 400; Fe, Mn, Zn, and Cu were measured by Varian AA240 AAS. The source reports total elemental metals only; no speciation is reported.

Implications

Certification: This paper contributes occurrence evidence for wild-harvested medicinal-plant raw material from a known mining/smelting contamination area and separate prepared-infusion evidence for Urtica dioica. Product-row synthesis should not pool the soil table with the plant table, and should keep dried plant material separate from the hot-water extraction table.

Courses: The study is a useful supply-chain case for soil-to-botanical transfer, showing that paired soil data can explain source risk without becoming product occurrence data.

App: The source can support herbal-botanicals and dried-herbs contamination profiles for Cd and Pb, with Zn, Cu, Fe, and Mn retained as cross-metal context for multi-element botanical surveys.

Wiki pages this source may touch

• herbal-botanical-infusions
• supplements-botanicals-herbs
• herbal-botanicals
• dried-herbs
• cadmium
• lead
• zinc
• copper
• iron
• manganese

Verification notes

• Identity checks on 2026-06-09: DOI 10.1515/aiht-2017-68-2990, raw handle MFK_10.1515-aiht-2017-68-2990, and cite-key kocevar-glavac2017-medicinal-plants-soil-metals returned no existing source page hits before creation.
• All Key numbers values were re-checked against /tmp/hmi-june9-005.txt extracted with pdftotext -layout. Table 3 plant occurrence rows, Table 1 soil context rows, Table 4 bioconcentration factors, and Table 5 hot-water extraction values are transcribed without unit conversion.
• Speciation check: Cd, Pb, Zn, Cu, Fe, and Mn are total elemental measurements by AAS; no arsenic, mercury, Cr-VI, or other speciation issue is present.
• Soil-only values are included as supply-chain context and are not treated as product occurrence. The routeable values are the plant concentrations and the Urtica dioica hot-water extract values.
• License left unknown; the extracted PDF did not show an explicit Creative Commons or reuse license statement.
• No sampled-product brand names are present. Place names are retained because they are geographic sampling locations, not commercial sampled-product identifiers.

Page history

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