Comparison of Essential and Toxic Metals Levels in some Herbal Teas: a Systematic Review

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#teas-herbal #cadmium #arsenic #metals-heavy #tea

Comparison of Essential and Toxic Metals Levels in some Herbal Teas: a Systematic Review

Salmani et al., 2024 | Biol Trace Elem Res | Systematic Review

Citation

Salmani Mohammad Hossein, Gholami Mahsa, ... Mokhberi Farnaz. Comparison of Essential and Toxic Metals Levels in some Herbal Teas: a Systematic Review. Biol Trace Elem Res. 2024-Feb;202(2):615-623. doi:10.1007/s12011-023-03698-w

Abstract

In the present study, we reviewed the literature as a systematic review to investigate the concentration of some metals (essential, none essential, and toxic metals) in herbal teas and their health risks. The search extended the literature from the database, including Google Scholar, PubMed, and Scopus, using the terms "herbal teas" combined with "heavy metals, essential metals, thyme, rosemary, chamomile, and tea" also with "iron, zinc, aluminum, chromium, cobalt, nickel, manganese, arsenic, cadmium, and lead" in titles and abstracts. The search was limited to articles published from 2012 to 2023 years. Initially, 212 articles were found; by detailed consideration, only 49 papers fit the inclusion criteria and were selected for further study. The mean of metal concentration, standard deviation, data distribution, and sample size were applied to generate data from the articles. The results indicated that all commonly consumed herbal teas included metals. None of them meet the requirements of the WHO requirements. However, more than 70% of their health risks are acceptable. The risks of arsenic and lead in tea and cadmium in black tea were considerably higher than in others. According to the review results, it is important to prevent heavy metal contamination of herbal teas by modifying cultivation patterns and also to prevent to consumption of low-quality herbal teas.

Key Findings

According to the review results, it is important to prevent heavy metal contamination of herbal teas by modifying cultivation patterns and also to prevent to consumption of low-quality herbal teas.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population See abstract
Sample Size See abstract
Age Range 2012 to 2023 years
Condition See abstract

MeSH Terms

  • Teas, Herbal
  • Cadmium
  • Arsenic
  • Metals, Heavy
  • Tea

Evidence Classification

  • Level: Systematic Review
  • Publication Types: Systematic Review, Journal Article
  • Vertical: chromium

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09