Comparison of Fluoride Ion Concentration in Black, Green and White Tea

Abstract

Back ground: Tea is one of the most commonly used drinks in the world. Drinking too much tea might affect the health. Tea is known for its fluoride resources; hence, consuming tea especially together with other fluoride resources can increase the risk of appearance of dental fluorosis. Considering the unspecified concentration of fluoride in white tea in Iran, the current study has carried out to evaluate the concentration of fluoride in different types of black tea, green tea and white tea of Refah Factory of Lahijan. Method and Material: In this study, the content of the fluoride of the black, green and white teas were measured. One gram samples of each type of tea were provided. Each time, the samples were placed in 200 milliliters of boiling distilled water, then it was moved to 80 degrees of Celsius incubator to be brewed. After 5 and 15 minutes, the solution was filtered. Concentration of the fluoride was measured through chromatography method and was recorded by measure of milligrams per liter. Data were analyzed using SPSS21 software. And significant level of less than 0.05 was considered. Findings: The concentration of the fluoride of the black, green and white solutions at the time of 5 minutes of brewing were respectively 1.38, 1.07 and 0.18 milligrams per liter and significantly increased he concentration of fluoride in all three types of tea with increasing drainage time (p value<0.05). Conclusion: The concentration of the fluoride of the three tea types were significantly different, to the extent that the least fluoride concentration belonged to the white and the most concentration belonged to black tea at both brewing times. By increasing the time of brewing the tea, its concentration was increased.

Fluoride Content of Matcha Tea Depending on Leaf Harvest Time and Brewing Conditions

“…Thus, the use of higher temperatures is associated with an increase in the fluoride content of the infusion, which may lead to exceeding the safety limits for consumption, bearing in mind how many food products contain this mineral. Few scientific reports confirm that the positive correlation between the concentration of fluoride and the temperature of the infusion may be associated with an increase in the release of fluoride from dried plants, which may be related to the loosening of the raw material and an increase in kinetic energy [32][33][34]. In an article by P. Gupta and N. Sandesh, the influence of various brewing methods on the concentration of fluorides in 16 teas was examined.…”

The Influence of the Preparation of Tea Infusion on the Content of Fluoride and the Assessment of Health Risk for the Consumer in Poland

“…and various tea brewing conditions (time, tea weight to water volume ratio, and form of tea), the fluoride content in the infusion may be within a wide range. This is reflected in the literature data, according to which the fluoride content in tea infusions ranges for black leaf tea from 0.32 to 6.81 mg/L, black tea in bags from 0.6 to 6.01 mg/L, black granulated tea from 1.06 to 6.87 mg/L, leafy green from 0.06 to 5.31 mg/L, white from 0.37 to 5.39 mg/L, and pu-erh from 0.39 to 2.87 mg/L [23,29,31,38,39,[47][48][49][50][51][52].…”

Fluoride Toxicity Limit—Can the Element Exert a Positive Effect on Plants?

“…According to research. Esfehani et al [50] the differences in fluoride content depending on the type of tea are presented in Table 1. However, Mochammad [51] marked fluoride contents of tea after 5 min ranged from 0.95 to 4.73 mg/L for black teas, from 0.70 to 1.00 mg/L for green teas.…”

“…Fluoride concentration in all three types of tea (in mg/L) average time of brewing 5 and 15 min[50].…”