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HERDIN Record #: R07-USC-14052014314453 Submitted: 20 May 2014 Modified: 14 October 2014

Study of lead content of four selected herbal teas

With the growing popularity of herbal fomulations, there is no doubt that people are turning their attention to these kinds of products for health promotion. Believing in the "natural", as associated with herbal formulation, is related to being safe. Tea, as one form of herbal preparation, became the subject of this study because of its growing demand for public use. But as it popularity is boosting among masses, is it enough to say that consumption of herbal tea is safe just because it is natural? This study focused on proving the presesnce or absence of lead int the four selected tea. Four teas were selected according to their uses. These sample do not have the Bureau of Food and Drug (BFAD) registratiom numbers. The contents in the tea bag were digested in a microwave with the reagents nitric acid and hydrogen peroxide to the chosen heavy metal. The digested sample were analyzed at the University's Water Laboratory for lead content using the Atomic Absorption Spectroscopy. The concentration of lead can be calculated from the absorbance reading which is the data detected by the instrument . Results show that all test solutions had a recorded of below 0.0044 absorbance reading and all test solutions had an actual concentration of below 5ppm. The presence did not exceed the allowable limit set by the Bureau of Food and Drug(BFAD), thus researchers concluded that the selected four tea samples are safe to consume with regards to the lead content. The determination of presence or absence of other metals susch as arsenic and mercury in tea samples is recommended.

Publication Type
Thesis Degree
Publication Date
March 2009
LocationLocation CodeAvailable FormatAvailability
University of San Carlos - Josef Baumgartner Learning Resource Center, Science and Technology Section T/542w Abstract Print Format
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