Comparative Study of Heavy Metals in Soil and Selected Medicinal Plants

Overview

Shah and colleagues measured iron, copper, manganese, nickel, chromium, zinc, cadmium, and lead in four medicinal plant species and paired soils from two sampling points in District Karak, Khyber Pakhtunkhwa, Pakistan. The paper is occurrence evidence for herbal-botanical raw materials used in traditional medicine, with leaves, stems, and roots reported separately. Values are total elemental concentrations in mg/kg; chromium is total Cr, not Cr-VI.

Key numbers

All values below are from Tables 1 and 2 and are reported as mean +/- standard deviation in mg/kg. BDL means below detection limit in the source table. No unit conversion or wet/dry conversion is applied.

The plant-part maxima are Fe 79.6 mg/kg in Tamarix articulata root at Spot-1, Cu 17.67 mg/kg in Peganum harmala root at Spot-1, Mn 84.73 mg/kg in Peganum harmala root at Spot-1, Ni 14.73 mg/kg in Tamarix articulata root at Spot-2, total Cr 9.61 mg/kg in Rhazya stricta leaves at Spot-1, Zn 71.08 mg/kg in Peganum harmala root at Spot-1, Cd 1.93 mg/kg in Rhazya stricta root at Spot-1, and Pb 9.68 mg/kg in Peganum harmala root at Spot-1.

The paired soil rows are collection-site context and should not be pooled as medicinal-plant occurrence. The source reports soil ranges of Fe 235.53 to 341.90 mg/kg, Cu 6.04 to 71.89 mg/kg, Mn 111.04 to 247.62 mg/kg, Ni 3.90 to 23.53 mg/kg, total Cr 2.63 to 32.53 mg/kg, Zn 17.81 to 93.19 mg/kg, Cd 0.15 to 1.99 mg/kg, and Pb 2.08 to 16.57 mg/kg.

Methods (brief)

The authors collected the four medicinal plants and their surrounding root-zone soils from polluted and unpolluted sampling points in District Karak, Khyber Pakhtunkhwa, Pakistan. Plant roots were washed with running water and deionized water, dried in shade at 22-25 degrees C, crushed, powdered, and digested with HNO3/H2O2 in a 2:1 mixture on a hot plate at 130 degrees C until the volume reached 3 mL; soil samples were digested with HNO3 and HClO4. Final solutions were diluted to 25 mL and analyzed by flame atomic absorption spectrophotometry using nitrous oxide-acetylene flame. The source reports total elemental concentrations; it does not report arsenic, mercury, methylmercury, inorganic arsenic, or Cr-VI.

Implications

The paper contributes plant-part-specific occurrence data for medicinal-plant raw materials from Pakistan, including both essential trace elements and toxic metals. Downstream evidence work should keep plant rows separate from soil rows because the soil measurements describe collection context rather than product concentration.

Wiki pages this source may touch

• Ingredient class — botanicals/herbs/traditional formulas
• Herbal botanicals
• Dried Herbs
• Iron
• Copper
• Manganese
• Nickel
• Chromium
• Zinc
• Cadmium
• Lead

Verification notes

• Identity checks on 2026-06-09 found no existing source page for DOI 10.1155/2013/621265, raw handle MFK_shah2013, or cite key shah2013-medicinal-plants-metals-pakistan.
• All Key numbers were re-checked against Tables 1 and 2 in /tmp/hmi-june9-117.txt extracted with pdftotext -layout. Values, BDL cells, plant parts, and spot labels are copied from the source tables without rounding, averaging, or conversion.
• Units are preserved as mg/kg, the unit printed in the table titles and results text. The page does not convert to ppb.
• Speciation check: chromium is total Cr by FAAS, not Cr-VI. The source does not report arsenic or mercury species.
• Soil values are included only as paired collection-site context and should not be pooled as plant/product occurrence.
• Brand firewall check: no commercial product brands are reported; Sigma-Aldrich and Perkin Elmer are methods/vendor names only.
• Closed vocabulary check: products, ingredients, metals, and wiki-page links use slugs present in docs/gpt-collaboration/taxonomy-snapshot.md. Exact species names such as Capparis spinosa, Peganum harmala, Rhazya stricta, and Tamarix articulata do not all have closed ingredient slugs, so they remain in table text only.

Update history

The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and 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.