Fluoride Content in Tea

Introduction


Camellia sinensis, the tea plant, produces what can be called "true teas" such as green, black, and oolong (#Parkinson). Accumulation of Fluoride in the tea plant comes from its natural ability to absorb Fluoride from surrounding soil. It is estimated that up to 98% of the Fluoride content in the tea plant is deposited in its leaves, particularly the old ones, following the release of Fluoride from aluminum Fluoride complexes initially formed at the roots (#Lu, et al., 2004). Fluoride has been suggested as an efficient, cost-effective indicator of maturity as well as a negative indicator of quality. Reason for the latter is due to the increase of Fluoride content paralleling a decline in beneficial polyphenols as the tea plant ages (#Lu, et al., 2004). The most notable catechin polyphenol found in Camellia sinensis is epigallocatechin gallate (EGCG), a strong anti-oxidant that reduces LDL and acts as an anti-Cancer agent (#Parkinson).

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Release of Fluoride from Tea


Tea infusion readily releases Fluoride from tea leaves into water. As such, it is considered a significant dietary source of Fluoride (#Lu, et al., 2004). Studies from certain countries have found teas containing 0.03 ppm-25.7 ppm Fluoride (#Szpir, 2005). Alongside consideration of when leaves are harvested relative to the growth of the tea plant and which leaves are selected for a particular tea, processing can be another determinant in Fluoride content of the final tea product. One study done in Taiwan found tea packaged in teabags had higher Fluoride concentrations in infusions than loose leaf teas (#Lung, et al., 2003).

Regulation


The current FDA regulation standard for fluoride levels in beverages and bottled water is 1.4-2.4 ppm (#US FDA, 2006). Certain American brand teas have been found to exceed the standard amount (#Rao, 1984). Studies from other countries have also found their local teas to contain fluoride levels higher than the recommended amounts (#Lung, et al., 2003 and #Tokalioglu, et al., 2004).

The EPA has an enforceable standard of 4 mg/L for fluoride content in drinking water alongside a recommended standard of 2 mg/L to protect against dental fluorosis and advises kids under the age of 9 to not drink water exceeding the recommended standard (#EPA).

Instant Tea Mixes


Instant tea brands in the United States have recently come under scrutiny after a woman developed bone fluorosis, following her daily drinking regimen of 1-2 gallons of instant ice tea. Recent testing published in The American Journal of Medicine (Jan 2005) show that Fluoride levels of several instant tea drinks from American brands including Lipton and Arizona range from 1.0-6.5 ppm (#WebMD, 2005).


 

References



EPA gound water and drinking water: Current drinking water standards. Available at: http://www.epa.gov/safewater/hfacts.html. Accessed July 11, 2007.


Lu, Y., Guo, W.F., & Yang, X.Q. 2004. Fluoride content in tea and its relationship with tea quality. J. Agric. Food Chem. 52: 4472-4476.


Lung, S.C., Hsiao, P.K., & Chiang, K.M. 2003. Fluoride concentrations in three types of commercially packed tea drinks in Taiwan. Journal of Exposure Analysis & Environmental Epidemiology. 13(1): 66-73.


Parkinson, R. Green tea health benefits: the miracle of tea. About.com. Available at: http//chinesefood.about.com/library/weekly/aa011400a.htm. Accessed May 5, 2006.


Szpir, M. 2005. Food safety: A tea-time mystery. Environ. Health Perspect. 113(8):A518.


Tokalioglu, S. Kartal, S. Sahin, U. 2004. Determination of fluoride in various samples and some infusions using a fluoride selective electrode. Turk J Chem. 28:203-211.


United States Food and Drug Administration, Department of Health and Human Services. Bottled water. 2006. (codified at 21CFR165.110).


Rao, G. 1984. Dietary intake and bioavailability of fluoride. Ann. Rev. Nutr. 4: 115-36.


WebMD Medical News. (Jan 25, 2005). "Harmful fluoride levels found in instant tea: Instant ices tea mixes may contain excessively high fluoride levels". Retrieved July 11, 2007..

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