A new study by scientists based in the University of Derby has sent out a strong warning to the Irish government and to the health authorities here.
The study found that British supermarket economy teas contain ‘significantly elevated’ levels of fluoride. The study will ring alarm bells in Ireland, since we drink even more tea than the British – in addition to which we use fluoridated tap water in our kettles, thus raising even further the poisonous fluoride content in the ‘humble cuppa’.
The article, entitles “Human exposure assessment of fluoride from tea (Camellia sinensis L.): A UK based issue?”, was published in a recent issue of Food Research International. It provides evidence that consuming even an average quantity of 1 litre (four cups) a day of economy tea will lead to fluoride overexposure. The resulting excess fluoride in the diet can result in serious, detrimental health effects including dental fluorosis (mottling and structural damage of the teeth) and skeletal fluorosis (a painful arthritic-like condition that have crippling effects).
The UK study, conducted by scientists Laura Chan, Aradhana Mehra, Sohel Saikat and Paul Lynch, measured fluoride concentrations in 38 brands of tea currently on sale in the UK. It found the lowest levels of fluoride (less than 2mg/L) in pure blend and speciality teas such as Assam leaf and Pu’er. Fluoride concentrations increased through black blends, green blends and economy blends, with the latter showing alarmingly high fluoride levels of 6mg/L on average. The highest fluoride concentrations were found in Tesco and Asda economy tea-bags.
“We want the public to know that there are extremely high levels of fluoride in the teas people are drinking, and that there are health risks associated with too much fluoride,” warned scientist Laura Chan when I spoke to her over the phone.
The science can sometimes baffle people, but it is worth listening carefully.
“The National Academy of Sciences in the US recommends a dietary reference intake (DRI) of 4mg of fluoride per day for adults,” Laura Chan explained. “In our study, the DRI of 4 mg/day was used to calculate the percentage of fluoride potentially available for uptake by the human system from consuming 1 L of tea (four cups) using a 2-minute infusion, which is considered typical for preparing tea.
“We found that black blend teas with an average fluoride level of 3.3mg/L,” explains Chan, “provided between 42-66% of the daily recommended intake of fluoride, and provided 88% of the DRI if taken on an empty stomach. More worryingly, we found that economy teas with an average fluoride level of 6mg/L provide 75-120% of the daily recommended intake of fluoride, and up to 150% if taken on an empty stomach.
“In the light of how much fluoride we are consuming just from tea alone,” adds Chan, “we need to remember that tea is not the only source of fluoride in the diet; other sources include oral hygiene products, wine and seafood.”
Many medicines also contain fluoride. And in Ireland, a more perilous dimension is introduced by mandatory fluoridation of the water supply.
Speaking to Hot Press, Dr Paul Lynch, another scientist involved in the British study, made precisely this point. “In a country like Ireland, where the water is fluoridated,” he said, “all of the food products that are made with that water will also carry high levels of fluoride. So it becomes a vicious circle in terms of fluoride consumption.”
While anti-fluoride campaigners in Ireland have frequently been dismissed as cranks and subjected to ridicule – and have consistently been stonewalled accordingly by the Department of Health, until Hot Press began its current investigation – their dire warnings are directly supported by the University of Derby scientific team.
The UK article refers to international scientific studies which report on dental incidences from the consumption of teas containing high concentrations of fluoride. It also highlights an increased incidence in China, India and Tibet of dental and skeletal fluorosis as a result of excessive fluoride intake.
“Other literature suggests a possible link between exposure to fluoride with cancer,” the UK article states. “Tohyama (1996) published a positive correlation between fluoride intake and uterine cancer in the Japanese prefecture of Okinawa. Takahashi, Akiniwa, and Narita (2001) suggested fluoride should be considered as a cause of oral cavity and pharynx, colon and rectum, hepato-biliary and urinary organ cancers.”
“The concern,” asserts Laura Chan now, “is that if people are drinking lots of tea, and they have been recommended to drink lots of water (if it’s fluoridated), as well as being exposed to fluoride from toothpaste and other sources and their normal daily food, people can be overexposed to fluoride content in their bodies, and they could start suffering.”
And the risk of overexposure among infants – completely ignored by the Irish Expert Body on Fluoride, the Department of Health and the Food Safety Authority of Ireland alike – is a matter of grievous concern.
“Particularly worrying,” Laura Chan told Hot Press, “is if you’re making formula milk for babies, and you’re using these fluoridated water supplies, you are giving those babies a high dose of fluoride, even higher than what you should be giving an adult.”
Make no mistake: the Derby University scientists’ measurements of fluoride in tea correspond with other international findings, and substantiate fully the research carried out by campaigning Irish scientist Declan Waugh. It was Waugh who brought to Hot Press’ attention the stark contrast between the levels of fluoride given in these tea studies, and the data for fluoride levels in tea being provided by the Food Safety Authority of Ireland (FSAI) – leading to the 27 Questioons asked of the authority this issue.
While the UK researchers found a fluoride average of 3.3mg/L in black teas and 6mg/L in economy teas, the FSAI give fluoride levels in tea being consumed in Ireland as a mere fraction of that ­– i.e. between 0.4 and 0.7mg/L.
I asked the UK scientists for their professional opinion on how the FSAI’s figures could be so much lower than their own findings, as well as in Declan Waugh’s research – and in the international scientific literature.
“Not knowing how the experiments were undertaken by the Irish government labs, we can’t make a direct comparison,” said Lynch. “We would need to look at exactly what sort of teas the Irish government analysed, and how they were analysed. But it does seem rather strange that the figures quoted by your government are so much lower that what’s in the published literature.
“Obviously in Ireland you drink teas that are similar to ours in Britain, so there is a sense that the work we’ve done could be corrrelated to the Irish situation,” Lynch continued. “But also remember that the water we used for the study was purified, non-fluoridated water. People in Ireland are drinking tea with similarly very high levels of fluoride, but they’re also using fluoridated water to make it.”
That makes the risk of fluoride over-exposure even higher – and more dangerous.
“Given the study we’ve done,” Lynch urged, “and given the Irish issue of water fluoridation, and how people around the world are currently reducing the areas of water fluoridation, fluoride exposure is something you should be strongly encouraging your government to look at.”
Which begs a final question: just how much evidence does the Minister with responsibility for fluoridation, Alex White, need before taking action? And how much more damage will be done while we are all waiting?