LEAD, MERCURY AND ARSENIC CONTENT IN SPICES: BLACK, WHITE AND GREEN PEPPER, BLACK CUMIN AND GINGER

Abstract

In order to evaluate the safety of selected commercial spices brands, concentration of lead, mercury and arsenic, as well as  moisture and mineral contents were analyzed in samples of dried black and white pepper powders, black, white and green peppercorns, black cumin seeds and ginger powder. Lead (Pb), mercury (Hg) and arsenic (As) concentrations in spice samples purchased from local markets in Belgrade were determined, after a microwave digestion of the samples, by atomic absorption spectrometry (AAS), using the graphite furnace AAS technique (Pb), cold vapor AAS technique (Hg) and hydride generation AAS technique (As). Trace levels of Pb, Hg and As in the selected dried spices samples were in the range 0.10 ppm - 0.79 ppm, 0.01 ppm - 0.10 ppm and 0.01 ppm - 0.51 ppm, respectively. The maximum Pb concentration was determined in the sample of ginger and it was 0.79 ppm, the maximum concentration of Hg was 0.10 ppm, determined in green peppercorns samples, while the maximum concentration of As in powdered black pepper sample was 0.51 ppm. The moisture and mineral contents in the different analyzed spices were in the range 1.70-13.10% and 3.40-6.50%, respectively. According to the obtained results, the concentrations of the analyzed toxic elements, as well as the moisture and mineral content in selected spices, were below the maximum permissible limits declared by the national legislations deemed safe for human consumption. SADRŽAJ OLOVA, ŽIVE I ARSENA U ZACINIMA: CRNI, BELI I ZELENI BIBER, CRNI KIM I ĐUMBIR U ovom radu, u cilju utvrđivanja bezbednosti odabranih komercijalnih zacina, analizirane su koncentracije teskih metala, kao i sadržaj vlage i ukupnih mineralnih materija, u uzorcima susenog crnog i belog bibera u prahu, crnog, belog i zelenog bibera u zrnu, semena crnog kima i đumbira u prahu. Koncentracije olova (Pb), žive (Hg) i arsena (As) u uzorcima zacina iz lokalnih prodavnica u Beogradu, određene su nakon mikrotalasne digestije atomskom apsorcionom spektrometrijom (AAS), primenom tehnike grafitne peci (Pb), tehnike hladne pare (Hg) i hidridne tehnike (As). Određene koncentracije Pb, Hg i As u uzorcima susenih zacina su u opsegu 0,10 ppm - 0,79 ppm, 0,01 ppm - 0,10 ppm i 0,01 ppm - 0,51 ppm, redom. Maksimalna koncentracija Pb od 0,79 ppm određena je u uzorku đumbira, maksimalna koncentracija Hg od 0,10 ppm u uzorcima zelenog bibera u zrnu, dok je maksimalna koncentracija As određena u uzorku crnog bibera u prahu i iznosila je 0,51 ppm. U uzorcima ispitivanih zacina sadržaj vlage i mineralnih materija je u opsegu 1,70-13,10% i 3,40-6,50%, redom. Dobijeni rezultati pokazuju da su koncentracije ispitivanih teskih metala, kao i sadržaj vlage i mineralnih materija ispod maksimalno dozvoljenih vrednosti propisanih zakonskom regulativom Republike Srbije, kao i da su ispitivani uzorci crnog, belog i zelenog bibera u prahu i zrnu, crnog kima u zrnu i đumbira u prahu propisanog kvaliteta u ovom smislu. HIGHLIGHTS Commercially formulated anti-dandruff shampoos contain zinc pyrithione (ZPT) as an active ingredient that has antifungal, antibacterial and anti-seborrheic effects; In ZPT, pyrithione (PT) forms a complex with a zinc ion in the 2 : 1 ratio; Determination of ZPT concentration in commercial anti-dandruff shampoos by differential pulse polarography was based on an electrochemical reduction of zinc ions in ammoniacal buffer at pH 10.2; Surface active ingredients (anionic and amphoteric) and micro-components in the shampoos did not exert a polarographic interference for the determination of zinc and did not affect the determination of the content of ZPT active ingredient; This simple and sensitive differential pulse polarography method is suitable for a routine and rapid control of the active ingredient content, as well as for the quality control of anti-dandruff shampoos.