Tea

REFERENCE SET:

Tea & Fluorosis - Global Perspective
(2006)

Latest News:

NEW RESEARCH: Scientists call for governmental and international agencies to adopt safe standards of fluoride content in tea commodities.
(February 2006)

Tibet:
Tea-induced dental fluorosis not just “cosmetic”
(Feb. 23, 2005)

USA:
Fluoride in Instant Teas
(Jan. 25, 2005)

(More pages are in the PFPC Members Science section)

Fluoride in Tea: USA

Fluoride in Tea: UK

Chile:

Sergio-Gomez S, Weber A, Torres C - "Fluoride content of tea and amount ingested by children" Odontol Chil 37(2):251-5 (1989)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2641960&dopt=Abstract

    “...Sixty eight per cent of children drinking tea as usual beverage, therefore it was estimated that about 22.1% of this sample have risk of dental fluorosis.”

Villa AE, Guerrero S - “Caries experience and fluorosis prevalence in Chilean children from different socio-economic status” Community Dent Oral Epidemiol 24(3):225-7 (1996)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8871025&&dopt=Abstract

    “Differences in prevalence and severity of enamel fluorosis between both groups are tentatively attributed to a different pattern of tap water and tea consumption at pre-school ages.”

Senegal:

Pontie M, Rumeau M, Ndiaye M, Diop CM - “The fluorosis problem in Senegal: data evaluation and presentation of a new method for defluoridating the water supply” Sante 6(1):27-36 (1996)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8612011&dopt=Abstract

Yam AA, Kane AW, Cisse D, Gueye MM, Diop L, Agboton P, Faye M - “Traditional tea drinking in Senegal. A real source of fluoride intake for the population” Odontostomatol Trop 22(87):25-8 (1999)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11372150&dopt=Abstract

Kenya:

Opinya GN , Bwibo N, Valderhaug J, Birkeland JM, Lokken P - “Intake of fluoride through food and beverages by children in a high fluoride (9 ppm)
area in Kenya” Discovery Innovation 3 (4):71-76 (1991)

  • “Tea accounted for nearly half of the fluoride intake among 1-2-year-old children.”

Opinya GN, Valderhaug J, Birkeland JM, Lokken P = “Fluorosis of deciduous teeth and first permanent molars in a rural Kenyan community” Acta Odontol Scand 49(4):197-202 (1991)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1927283&form=6&db=m&Dopt=r

China/Tibet/BrickTea:

Cao J, Liu JW, Tang LL, Sangbu DZ, Yu S, Zhou S, Yu Y, Qu HY - "Dental and early-stage skeletal fluorosis in children induced by fluoride in brick-tea" Fluoride 38(1):44-47 (2005)

    Fluorosis from brick-tea was discovered during the last decade in western and northern parts of China. Dental fluorosis has a high prevalence among children in these brick-tea endemic areas, but skeletal fluorosis does not normally become apparent until adulthood. In July 2002 we examined 132 primary school children, age 8 to 13 years, in a low-fluoride area of Naqu County, Tibet, and found that 111 of the children (84.1%) had dental fluorosis from drinking traditional brick-tea. Among these 111 children, 96 (86.5%) were found by radiological examination to have developmental skeletal abnormalities in the wrist. We view these findings as warning signs of early-stage skeletal fluorosis indicating that dental fluorosis in children should be considered more than a matter of cosmetic concern.

Cao et al. - “Prevention and control of brick-tea type fluorosis--a 3-year observation in Dangxiong, Tibet” Ecotoxicol Environ Saf 56(2):222-7 (2003)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12927553&dopt=Abstract

Cao J, Bai X, Zhao Y, Liu J, Zhou D, Fang S, Jia M, Wu J - "The relationship of fluorosis and brick tea drinking in Chinese Tibetans" Environ Health Perspect 104(12):1340-3 (1996)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9118877&dopt=Abstract

Cao J, Zhao Y, Liu J - "Brick tea consumption as the cause of dental fluorosis among children from Mongol, Kazak and Yugu populations in China" Food Chem Toxicol 35(8):827-33 (1997)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8883478&dopt=Abstract

Cao J, Zhao Y, Liu JW - "Safety evaluation and fluorine concentration of Pu'er brick tea and Bianxiao brick tea" Food Chem Toxicol 36(12):1061-3 (1998)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9862647&dopt=Abstract

Cao J, Chen H, Zhao Y, Liu J, Shen N - "Dental fluorosis of brick tea type in rats" Hunan I Ko Ta Hsueh Hsueh Pao 23(3):257-60 (1998)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10681753&dopt=Abstract

Turkey:

Şükrü Kalayci S, Somer G - “Factors affecting the extraction of fluoride from tea: application to three tea samples” Fluoride 36(4):267-270 (2003)

    Summary: Infusion time and water hardness were examined for their effects on fluoride extraction from three different brands of tea (Çaykur-Kamelya, Rize-Turist, and Lipton-Ceylon). With soft water (18 mg eq CaCO3/L), extraction after 10 min at 80°C was over 90% complete but only 75% with hard water (79mg eq CaCO3/L). After extraction for 20 min with soft water, the water-soluble fluoride contents of the three brands of tea were determined as 98, 53, and 83 ppm, respectively. Addition of lemon or lemon juice to the tea extract did not change free fluoride content.

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

US:

Behrendt A, Oberste V, Wetzel WE - “Fluoride concentration and pH of iced tea products” Caries Res 36(6):405-10 (2002)
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12459612

Chan JT,  Koh SH -"Fluoride content in caffeinated, decaffeinated and herbal teas" Caries Res 30(1):88-92 (1996)

Chan JT, Yip TT,  Jeske AH - "The role of caffeinated beverages in dental fluorosis" Med Hypotheses 33(1):21-2 (1990)

Cook HA - “Crippling arthritis related to fluoride intake: Case report” Fluoride 5 (4):209-213 (1972)

  • “In a 55-yr-old woman with long-standing arthritis, but no obvious signs of fluorosis, X-rays exhibited degeneration of discs and calcification in disc spaces. Her daily fluoride intake, mainly from tea, exceeded 9 mg; her daily urinary excretion was 3 mg. When she discontinued consuming tea, her fluoride intake fell below 1 mg daily; excretion through the urine exceeded intake; the arthritic pains iminished and virtually ceased in 6 mo; mobility of her spine was restored and she was able to resume work. Arthritis of the spine of unknown cause might represent subclinical fluorisis which is not demonstrable radiologically.”

Whyte MP, Essmyer K, Gannon FH, Reinus WR - “Skeletal fluorosis and instant tea” Am J Med 118(1):78-82 (2005)

Jordan:

Fraysse C, Bilbeissi MW, Mitre D, Kerebel B - "The role of tea consumption in dental fluorosis in Jordan" Bull Group Int Rech Sci Stomatol Odontol 32(1):39-46 (1989)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2924014&dopt=Abstract

    “For social and climatic reasons, Jordanian children drink daily high quantities of tea. Analysis of tea prepared on Jordanian way revealed a concentration of 1.2 mg F/l. This continuous intake of fluoride might explain the high severity of dental fluorosis in Jordan.”

India:

Gulati P, Singh V, Gupta MK, Vaidya V, Dass S, Prakash S - "Studies on the leaching of fluoride in tea infusions" Sci Total Environ 138(1-3):213-21 (1993)

“Danger Of Fluorosis Increases With Intake Of Black Tea” - Times of India/Dainik Bhasker - Aug.8, 2001

  • “As black tea, pan masala and toothpastes have very high fluoride contents, they increase the possibility of causing fluorosis. This was told by Health & Family Welfare Minister Mr. Rajendra Choudhry during the inauguration of book ‘Fluorosis In Rajasthan’ yesterday in Jaipur.

Israel:

Mann J, Sgan-Cohen HD, Dakuar A, Gedalia I - "Tea drinking, caries prevalence, and fluorosis among northern Israeli Arab youth" Clin Prev Dent 7(6):23-6 (1985)

Shomar B, Muller G, Yahya A, Askar S, Sansur R - “Fluorides in groundwater, soil and infused black tea and the occurrence of dental fluorosis among school children of the Gaza strip” J Water Health 2(1):23-35 (2004)
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15384727&query_hl=3&itool=pub med_docsum

    “The occurrence of the disease was due to intake of high amounts of fluorides in drinking water, tea and fish. Communication with population indicated a heavy intake of tea starting from a very young age; not uncommonly tea is put in nursing bottles.”

Ireland:

Kavanagh D, Renehan J - “Fluoride in tea--its dental significance: a review” J Ir Dent Assoc 44(4):100-5 (1998)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10530119&dopt=Abstract

Pakistan:

Cook HA - “Case report-tea and fluorosis” Pak Dent Rev 18(3):100 (1968)

Poland:

Skorkowska-Zieleniewska - “In heavy tea and coffee drinkers nutritional status of fluoride in relation to that of other mineral elements.” Fluoride 16 (1):20-23 (1983)

Sri Lanka:

van der Hoek W, Ekanayake L, Rajasooriyar L, Karunaratne R - “Source of drinking water and other risk factors for dental fluorosis in Sri Lanka” Int J Environ Health Res. 13(3):285-93 (2003)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12909559&dopt=Abstract

Taiwan:

Lung SC, Hsiao PK, Chiang KM - “Fluoride concentrations in three types of commercially packed tea drinks in Taiwan” J Expo Anal Environ Epidemiol 13(1):66-73 (2003) FULL PAPER

Germany:

Behrendt A, Oberste V, Wetzel WE - “Fluoride concentration and pH of iced tea products” Caries Res. 36(6):405-10 (2002)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12459612&dopt=Abstract

pH & Calcium

Ruan J, Ma L, Shi Y, Han W - “The Impact of pH and Calcium on the Uptake of Fluoride by Tea Plants (Camellia sinensis L.)” Ann Bot (Lond) 93(1):97-105 (2004)
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12927553&dopt=Abstract

OTHER:

Kjellevold Malde M, Greiner-Simonsen R, Julshamn K, Bjorvatn K - “Tealeaves may release or absorb fluoride, depending on the fluoride content of water” Sci Total Environ. 2005 Dec 11
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16356534&query

Lu Y, Guo WF, Yang XQ - “Fluoride content in tea and its relationship with tea quality” J Agric Food Chem 52(14):4472-6 (2004)
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15237954&query_hl=3&itool=pub med_docsum

Aluminum and Fluoride

Fung KF, Zhang ZQ, Wong JW, Wong MH - “Aluminium and fluoride concentrations of three tea varieties growing at Lantau Island, Hong Kong” Environ Geochem Health 25(2):219-32 (2003)

    The present project aims to investigate aluminium (Al) and fluoride (F) contents
    in teas (Camellia sinensis (L.) O. Kuntze). Three different commercial tea
    varieties: Assam variety and two China sub-varieties, a large leafed variety and
    small leafed variety, were collected in two tea gardens of Lantau Island tea
    plantation of Hong Kong. In general, high concentrations of Al and F were
    accumulated in the mature leaves (15.3 and of 2.07 g kg-1 respectively). Among
    the three varieties, 'the small leafed' variety exhibited the highest Al and F
    contents followed by the 'large leafed' variety whereas the Assam variety had
    the lowest Al and F concentrations in its tea bushes. Tea products from a
    plantation were also analysed and it was noted that black tea had higher Al and
    F concentrations than green tea. The amount of Al and F released into tea liquor
    was also tested and the results showed that higher concentrations of Al and F
    were released into tea liquor under repeated infusion method than continuous
    infusion method.