Polycyclic Aromatic Hydrocarbons in Commercial Herbal Teas

Abstract

Contamination of herbal teas with polycyclic aromatic hydrocarbons (PAHs) can occur as a result of environmental pollution as well as during processing. This research fits into current concerns directed towards establishing the PAHs' contamination level of plant resources, the focus being on the priority PAHs as established by the US Environmental Protection Agency's and by the European Union. In this study, the PAHs' content of several commercial herbal teas brands was assessed by reversed-phase high performance liquid chromatography (HPLC) using an Agilent 1100 system with fluorescence and photodiode array detectors. The obtained data revealed that the maximum overall PAH's contamination in the studied herbal teas was recorded for dandelion, mulberry and St.John's wort, all of these exposing high surface area of leaves; from the 15 tracked PAHs, only three were present in all samples (acenaphthene, fluorene and benzo(b)fluoranthene), while anthracene and benzo(g,h,i)perylene were quantified in only two samples; the maximum levels of individual PAHs were recorded in dandelion.

Human Health Risk Assessment of Arsenic and Other Metals in Herbal Products Containing St. John’s Wort in the Metropolitan Area of Mexico City

“…This may be due to the fact that the highest accumulation of heavy metals in plants is mainly in the leaves [ 61 ], which in this study were analyzed together with the stems ( Table 1 and Table 3 ) and are generally used to prepare infusions. In addition, previous studies have reported the presence of heavy metals in medicinal plants used for the preparation of herbal teas [ 62 , 63 , 64 , 65 , 66 , 67 ]. In this regard, toxic metals such as Cd, Pb and As affect the size, number, pigmentation and thickness of leaves [ 68 ].…”

A comprehensive analysis of chemical and biological pollutants (natural and anthropogenic origin) of soil and dandelion (Taraxacum officinale) samples

“…Previous studies have found T. officinale to demonstrate as much as 15-fold excess lead levels in plants growing near railway lines, accompanied by significant accumulations of PCB congeners [40,41]. In addition, studies of individual PAH levels in several commercial herbal teas have recorded high values of naphthalene, pyrene, phenanthrene and benzo(b)fluoranthene in dandelion tea [42], and mycotoxin multicontamination by aflatoxins, ochratoxin A, zearalenone, deoxynivalenol and citrinin have been noted in the plant [43]. However, no data exists regarding potential hazardous biological contaminants such as bacteria or fungi, particularly those that are pathogenic to humans and farm animals, nor by parasitic worms and protozoa.…”