Heavy metals in Herbal botanicals

Herbal botanicals overview

Herbal botanicals in the HMI library has 502 reported results for lead, cadmium, total arsenic, inorganic arsenic, dimethylarsinic acid, total mercury, nickel, chromium, aluminium, tin, Co, Cu, Fe, Mn, Zn, V, Ba, Mo, Sr and Tl from 28 sources.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2G. N. Abdel-Rahman, Mohamed B. M. Ahmed, Bassem A. Sabry, Safaa S. M. Ali · 2019Heavy metals content in some non-alcoholic beverages (carbonated drinks, flavored yogurt drinks, and juice drinks) of the Egyptian marketsToxicology ReportsRead source →3Angelon-Gaetz KA, Klaus C, Chaudhry EA, Bean DK · 2018Lead in Spices, Herbal Remedies, and Ceremonial Powders Sampled from Home Investigations for Children with Elevated Blood Lead Levels — North Carolina, 2011–2018MMWR Morbidity and Mortality Weekly ReportRead source →4Shchukin VM, Blinkova EA, Kuzmina NE, Luttseva AI · 2022Evaluation of Elemental Impurities in Peppermint Herb and Peppermint-Based Herbal ProductsRegulatory Research and Medicine EvaluationRead source →5Assaad N, Fadel D, Argyraki A, Kypritidou Z, Bakir A, Awad E · 2020Heavy Metals Accumulation in the Edible Vegetables of Lebanese Tabbouli SaladJournal of Agricultural Science 12(7):155-162Read source →6Bua DG, Annuario G, Albergamo A, Cicero N, Dugo G · 2016Heavy metals in aromatic spices by inductively coupled plasma-mass spectrometryFood Additives & Contaminants: Part BRead source →} WHO GEMS/Food submissions reported lead in herbal botanicals, as sold from 1,791 results in 5 reporting regions, with subgroup medians from 2.2 to 1,690 µg/kg.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} For cadmium, GEMS/Food gave subgroup medians from 9 to 400 µg/kg from 1,056 results.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

Across 2 other studies of ordinary farms and markets, reported lead means and medians on an as-sold or fresh-weight basis ranged from 60 µg/kg (Shchukin et al. 2022) to 2,570 µg/kg (Shchukin et al. 2022).^{4Shchukin VM, Blinkova EA, Kuzmina NE, Luttseva AI · 2022Evaluation of Elemental Impurities in Peppermint Herb and Peppermint-Based Herbal ProductsRegulatory Research and Medicine EvaluationRead source →} For cadmium, 6 studies on a dry-weight basis reported means and medians from 30 µg/kg (Falahati et al. 2025) to 430 µg/kg (Özden 2021).^{8Falahati Naghibi E, Mehdinia SM, Amouei A · 2025Health risk assessment of Pb, Cd, and Zn in leafy and bulb vegetables from northern Iran using Monte Carlo simulationEnvironmental Research Communications 7 (2025) 065030Read source →9Özden H · 2021Assessment of toxic metals in commonly used herbs and spices in Turkeyİstanbul Journal of Pharmacy 51(3): 392-397Read source →} Higher results came from contaminated or exposed settings rather than ordinary supply. Herbal botanicals, as sold from grown independently had total mercury higher at 14.2 µg/kg, against 9.39 µg/kg for all samples in the same study.^{7Fischer A, Brodziak-Dopierała B · 2022The Mercury Concentration in Spice PlantsProcessesRead source →}

For a buyer the practical points are the form bought, the basis a result is reported on, where the herbal botanicals came from and the laboratory’s reporting limit. Testing finds contamination but does not remove it.

What counts as herbal botanicals

This page covers herbal botanicals in 5 forms kept separate in every comparison: herbal botanicals, as sold (425 results), herbal botanicals, oil (49 results), herbal botanicals, powder or ground (15 results), herbal botanicals, dried (7 results) and herbal botanicals, flour or meal (6 results).^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2G. N. Abdel-Rahman, Mohamed B. M. Ahmed, Bassem A. Sabry, Safaa S. M. Ali · 2019Heavy metals content in some non-alcoholic beverages (carbonated drinks, flavored yogurt drinks, and juice drinks) of the Egyptian marketsToxicology ReportsRead source →3Angelon-Gaetz KA, Klaus C, Chaudhry EA, Bean DK · 2018Lead in Spices, Herbal Remedies, and Ceremonial Powders Sampled from Home Investigations for Children with Elevated Blood Lead Levels — North Carolina, 2011–2018MMWR Morbidity and Mortality Weekly ReportRead source →4Shchukin VM, Blinkova EA, Kuzmina NE, Luttseva AI · 2022Evaluation of Elemental Impurities in Peppermint Herb and Peppermint-Based Herbal ProductsRegulatory Research and Medicine EvaluationRead source →5Assaad N, Fadel D, Argyraki A, Kypritidou Z, Bakir A, Awad E · 2020Heavy Metals Accumulation in the Edible Vegetables of Lebanese Tabbouli SaladJournal of Agricultural Science 12(7):155-162Read source →6Bua DG, Annuario G, Albergamo A, Cicero N, Dugo G · 2016Heavy metals in aromatic spices by inductively coupled plasma-mass spectrometryFood Additives & Contaminants: Part BRead source →}

Results stay on the basis each source reports: as sold or fresh weight, dry weight, or unstated. Dry-weight, as-sold and unstated results are never pooled, and no moisture conversion is applied.

Heavy metal contamination profile of herbal botanicals

The table holds every extracted herbal botanicals result: one row for each statistic a source reports for a form, group and metal, 502 rows in all, grouped by metal and form; percentiles, ranges and maxima for the same samples as a mean or median are shown on that row.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2G. N. Abdel-Rahman, Mohamed B. M. Ahmed, Bassem A. Sabry, Safaa S. M. Ali · 2019Heavy metals content in some non-alcoholic beverages (carbonated drinks, flavored yogurt drinks, and juice drinks) of the Egyptian marketsToxicology ReportsRead source →3Angelon-Gaetz KA, Klaus C, Chaudhry EA, Bean DK · 2018Lead in Spices, Herbal Remedies, and Ceremonial Powders Sampled from Home Investigations for Children with Elevated Blood Lead Levels — North Carolina, 2011–2018MMWR Morbidity and Mortality Weekly ReportRead source →4Shchukin VM, Blinkova EA, Kuzmina NE, Luttseva AI · 2022Evaluation of Elemental Impurities in Peppermint Herb and Peppermint-Based Herbal ProductsRegulatory Research and Medicine EvaluationRead source →5Assaad N, Fadel D, Argyraki A, Kypritidou Z, Bakir A, Awad E · 2020Heavy Metals Accumulation in the Edible Vegetables of Lebanese Tabbouli SaladJournal of Agricultural Science 12(7):155-162Read source →6Bua DG, Annuario G, Albergamo A, Cicero N, Dugo G · 2016Heavy metals in aromatic spices by inductively coupled plasma-mass spectrometryFood Additives & Contaminants: Part BRead source →} Monitoring medians are HMI calculations from individual submissions; non-detects remain intervals between zero and the reporting limit and are never read as zero.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

149 rows can be rated against an HMI reference for the same form and basis, 136 rows have a direct same-study comparison, and the rest stay unrated with the reason recorded. 4 values from 3 sources failed a check against their own source and are shown but not compared.^{6Bua DG, Annuario G, Albergamo A, Cicero N, Dugo G · 2016Heavy metals in aromatic spices by inductively coupled plasma-mass spectrometryFood Additives & Contaminants: Part BRead source →10Adeniyi O, Bayo D, Adeniyi A, Okeke-Agulu K · 2021Assessment of Heavy Metals Concentration and Health Risks of Selected Vegetables Sold In Jos MetropolisArchives of Medical Case Reports and Case Study 4(5)Read source →11Sarita Patel, Manisha Pradhan, Ashish Patel · 2023Evaluation of heavy metals in herbal plants growing in Singrauli Region of Madhya PradeshInternational Journal of Chemical and Biological SciencesRead source →}