The content of lead in herbal drugs and tea samples

Abstract

Heavy metals are highly toxic to living organisms even in low concentrations owing to their cumulative effect. In this study the overall content of lead in herbal drugs was determined, as well as the content of lead which was released from tested drugs during the preparation of tea drinks. To determine the content of toxic lead, the highly sensitive microanalytical technique of the potentiometric stripping analysis (PSA) with oxygen as the oxidant was used. The lowest overall content of lead was detected for chamomile and ranged from 0.73 to 0.77 µg/g, while the greatest content of lead was determined in the samples of the frangula bark, and yielded approximately 3 µg/g. The lead content in the prepared tea drinks ranged from 0.26 to 1.23 µg/g and depended on the manner in which tea drink was prepared. All of the herbal drugs in this study contain a certain amount of the toxic metal lead, but at the same time, the contents were below the levels prescribed for this metal. The content of lead released from the herbal drug into the tea drink was three to five times lower than those of the overall content of this metal.

Analysis of Tea for Metals by Flame and Graphite Furnace Atomic Absorption Spectrometry with Multivariate Analysis

“…Mint, nettle, St. John's Wort, and thyme represent relatively well-studied herbs (mint: Gallaher et al 2006;Gentscheva, Stafilov, and Ivanova 2010;Pytlakowska et al 2012;Rubio et al 2012;Tokalıoglu 2012;Prkić et al 2013;Dghaim et al 2015;Aziz et al 2016;nettle: Łozak et al 2002;Özcan et al 2008;Kara 2009;Balabanova, Stafilov, and Bačeva 2015;Samolińska et al 2017; St. John's Wort: Baranowska et al 2002;Ražić et al 2005;Pytlakowska et al 2012;Muntean et al 2013;Mihaljev 2014;thyme: Arpadjan et al 2008;Özcan et al 2008;Karadas and Kara 2012;Mihaljev 2014;Milani, Morgano, and Cadore 2016). For the rest of the examined tea samples, significantly lower number of studies have been performed (hawthorn: Özcan et al 2008;Juranović Cindrić et al 2015;Konieczynski, Arceusz, and Wesolowski 2015;yarrow: Ražić et al 2005;Arpadjan et al 2008;Mihaljev et al 2014;elderflower: Gasser et al 2009;Konieczynski, Arceusz, andWesolowski 2015 andbearberry: Arpadjan et al 2008;Kaličanin and Velimirović 2013). In general, the majority of studies deal with the determination of the total metals, while others also determined metals in the infusions.…”

Heavy Metal Concentration in Black Tea in Iran

“…Therefore, health of tea is a very important factor and consumers of this beverage should be assured on the absence of pollutants such as heavy metals in consumed tea. Heavy metals are very toxic elements to living organisms even in low concentrations because of their cumulative effects, may cause some problems such as cancer and other dangerous diseases (36,37). In this study, the level of two essential elements (Mn and Cu) and one non-essential element (Cd) in commercially available black tea from different brands was determined by ICP.…”

Comparative Analysis of Heavy Metal and Arsenic Content in Various Herbal Dosage Forms Marketed in Russia

“…Полученные данные о содержании свинца в ЛРП хорошо согласуются с данными отечественных и зарубежных исследователей [10][11][12][13][14][15][16], что свидетельствует об отсутствии существенных различий в контаминации свинцом дикорастущих и выращиваемых растений. Следует отметить, что содержание свинца в растениях очень чувствительно к влиянию антропогенного фактора [17,18], так, например, повышенное содержание свинца в ЛРП наблюдается в местах разработки свинцовых руд и в районе расположения металлообрабатывающих предприятий [19,20], отмечено увеличение содержания свинца (до 25 мг/кг) в образцах ЛРС из Кемеровской области [4].…”