%0 Journal Article
%T The Benefits and Risks of Consuming Brewed Tea: Beware of Toxic Element Contamination
%A Gerry Schwalfenberg
%A Stephen J. Genuis
%A Ilia Rodushkin
%J Journal of Toxicology
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/370460
%X Background. Increasing concern is evident about contamination of foodstuffs and natural health products. Methods. Common off-the-shelf varieties of black, green, white, and oolong teas sold in tea bags were used for analysis in this study. Toxic element testing was performed on 30 different teas by analyzing (i) tea leaves, (ii) tea steeped for 3-4 minutes, and (iii) tea steeped for 15¨C17 minutes. Results were compared to existing preferred endpoints. Results. All brewed teas contained lead with 73% of teas brewed for 3 minutes and 83% brewed for 15 minutes having lead levels considered unsafe for consumption during pregnancy and lactation. Aluminum levels were above recommended guidelines in 20% of brewed teas. No mercury was found at detectable levels in any brewed tea samples. Teas contained several beneficial elements such as magnesium, calcium, potassium, and phosphorus. Of trace minerals, only manganese levels were found to be excessive in some black teas. Conclusions. Toxic contamination by heavy metals was found in most of the teas sampled. Some tea samples are considered unsafe. There are no existing guidelines for routine testing or reporting of toxicant levels in ˇ°naturallyˇ± occurring products. Public health warnings or industry regulation might be indicated to protect consumer safety. 1. Introduction The drinking of tea has a history that likely began in China more than 3000 years ago. It has a relatively recent history in the west beginning in the 16th century when it was introduced to Portuguese priests and merchants. It became popular in Britain in the 17th century. The use of tea bags was not common until after WWII. Tea originates from the plant Camellia sinensis, a tree that may grow up to 52 feet in height unless cultivated. Tea plants require significant rainfall of 50 inches a year and grow in acidic soil. Contaminants may vary in the soil, air, or water in which the plants are grown. Acidic soil may result in excess available aluminum and fluoride [1]. An acid or alkali soil pH also enhances leaching of toxic heavy metals from the soil [2]. Increasing pH with soluble calcium would reduce the absorption of fluoride [1]. Environmental pollutants such as fluoride and aluminum have been found in tea in part due to the tea plants absorption and deposition and concentration of these compounds in the leaves [3]. The drinking of more than 5 liters of tea per week may result in dental or skeletal fluorosis [4]. Mercury, lead, arsenic, and cadmium as well as other toxic elements have been found in tea leaves as described in the literature
%U http://www.hindawi.com/journals/jt/2013/370460/