Linhares DP, Garcia PV, Amaral L, Ferreira T, Dos Santos Rodrigues A. Safety Evaluation of Fluoride Content in Tea Infusions Consumed in the Azores-a Volcanic Region with Water Springs naturally Enriched in Fluoride. Biological trace element research. 2017 Jan 24. doi: 10.1007/s12011-017-0947-9.
Tea is the second most commonly consumed beverage in the world. It is well recognized that the consumption of tea in high quantities can promote the development of fluorosis. The main objective of this study is to estimate the exposure to fluoride in the Azores through drinking tea prepared with water from different volcanic locations, by i) investigating the fluoride (F) content of various commercial brands of tea (Camellia sinensis) marketed in Azores and ii) comparing tea releasing rates of F according to brewing time, considering the fluoride concentration in the different types of water used for the infusion. Fluoride contents were determined by ion-selective electrode in 30 samples of drinking water from three different locations and in 450 samples of tea (black and green tea) from three different brands. Fluoride concentration in water ranged from 0.29 to 1.56 ppm (Porto Formoso and Sete Cidades village, respectively). Fluoride concentrations increased with brewing time, reaching the highest values in the Azorean black and green tea infusions. For all the studied brands, a negative correlation was found between tea fluoride contents and the pH of the water used to prepare the infusion. Fluoride concentration in infusions was significantly associated with the background fluoride concentration in drinking water. Since the fluoride concentration in groundwater varies accordingly to the geological conditions and tea consumption can contribute to fluoride intake, it is important to define the limits for tea consumption, particularly in fluoride-rich areas.
Wasana HM, Perera GD, Gunawardena PS, Fernando PS, Bandara J. WHO water quality standards Vs Synergic effect(s) of fluoride, heavy metals and hardness in drinking water on kidney tissues. Scientific reports 2017 Feb 14;7:42516. doi: 10.1038/srep42516.
Despite WHO standards, waterborne diseases among the human being are rising alarmingly. It is known that the prolong exposure to contaminated water has major impact on public health. The effect of chemical contaminations in drinking water on human being is found to be chronic rather than acute and hence can be defined “consumption of contaminated drinking water could be a silent killer”. As the WHO recommended water quality standards are only for individual element and synergic effects of trace metals and anions have not been considered, investigation of synergic effects of trace metals and anions and their effect on human being is of prime important research. By an animal trial, we investigated the synergic effect(s) of heavy metals, aluminium, arsenic, fluoride and hardness in drinking water on kidney tissues of mice. Our investigation strongly suggests existing of a synergic effect especially among Cd, F and hardness of water which could lead to severe kidney damage in mice, even at WHO maximum recommended levels. Hence, the synergic effect(s) of trace metals, fluoride and hardness present in drinking water should be investigated meticulously when stipulating the water quality at WHO maximum recommended levels.
Bandlapalli Pavani, Mandava Ragini, David Banji, Otilia J F Banji, N Gouri Pratusha. Fluoride Toxicity – A Harsh Reality. International Research Journal of Pharmacy, Vol 2, Iss 4, Pp 79-85 (2011).
There are many incidents of fluoride toxicity whether it is acute or chronic. Fluoride toxicity is an environmental hazard which arises from the upper layers of geological crust and is dissolved in water. Prolonged drinking of such water causes chronic fluoride toxicity. Use of fluoride containing compounds for various purposes such as dental products, metal, glass, refrigerator and chemical industries act as a source of fluoride poisoning and increase the risk of toxicity. This review reflects the deleterious effects of fluorides on various organs in the physiological system.
Spittle B. Development of Fluoride Toxicity Including Cognitive Impairment with Reduced IQ: Pathophysiology, Interactions With Other Elements, and Predisposing and Protective Factors. Fluoride. Jul-Sep2016, Vol. 49 Issue 3, Part 1, p189-193.
The development of toxicity to the fluoride ion (F) may be complex and multifactorial with a number of pathophysiological path ways being possible, with the potential for interactions between toxins involving additivity, synergism, and antagonism, and with a number of other factors having predisposing and protective effects. In addition to cognitive impairment with a reduced intelligence quotient (IQ) in children developing through other mechanisms such as disturbed thyroid hormone metabolism and sonic hedgehog signalling, other pathophysiological factors such as reduced brain glucose uptake following a fluoride-induced reduction in insulin secretion may contribute. Environmental contamination with cadmium in a coal combustion fluorosis-affected rural area within China’s Three Gorges region may contribute to the dental and skeletal health problems in the population and the possibility of interactions between Cd and F affecting cognitive functioning requires further investigation. The propensity for the development of toxicity to F may involve interactions with a number of other factors as well as the levels of F exposure.
Olszowski T, Sikora M, Chlubek D. Combined Toxicity of Fluoride and Cadmium. Fluoride. Jul-Sep2016, Vol. 49 Issue 3, Part 1, p194-203.
Fluoride (F – ) and cadmium (Cd) are toxicants found ubiquitously in the human environment. The aim of this review was to identify and characterize studies that attempted to determine the combined toxicity of F – and Cd. The effects of F – and Cd on liver and kidney (with a special focus on chronic kidney disease of unknown etiology), bone, tooth enamel, dental caries, and brain were taken into consideration. Based on the results of the studies described in this review, various types of combined toxicity of F – and Cd might occur: additive, synergistic, or antagonistic, with the latter two being true interactions. However, the type of combined action occurring seems to depend on many factors, such as which toxic effect is considered, the dose levels of F – and Cd and their dose ratio, exposure duration, presence of other elements, etc. Moreover , when analyzing the combined toxic effects of F – and Cd, the possible interactions of these toxicants with other elements (e.g., fluoride with aluminum and arsenic; cadmium with lead, arsenic, zinc, selenium, and calcium) should also be taken into consideration. We also may not exclude the independent action of F – and Cd on some selected functions/health outcomes. Due to the huge gaps in knowledge, additional studies are required to address this important public health issue, i.e., the combined effects of exposure to these common environmental toxicants , especially among people with high exposure to these elements.
Chakraborti D, Rahman MM, Chatterjee A, Das D, Das B, Nayak B, Pal A, Chowdhury UK, Ahmed S, Biswas BK, Sengupta MK, Lodh D, Samanta G, Chakraborty S, Roy MM, Dutta RN, Saha KC, Mukherjee SC, Pati S, Kar PB. Fate of over 480 million inhabitants living in arsenic and fluoride endemic Indian districts: Magnitude, health, socio-economic effects and mitigation approaches. Journal of trace elements in medicine and biology. 2016 Dec;38:33-45. doi: 10.1016/j.jtemb.2016.05.001.
During our last 27 years of field survey in India, we have studied the magnitude of groundwater arsenic and fluoride contamination and its resulting health effects from numerous states. India is the worst groundwater fluoride and arsenic affected country in the world. Fluoride results the most prevalent groundwater related diseases in India. Out of a total 29 states in India, groundwater of 20 states is fluoride affected. Total population of fluoride endemic 201 districts of India is 411 million (40% of Indian population) and more than 66 million people are estimated to be suffering from fluorosis including 6 million children below 14 years of age. Fluoride may cause a crippling disease. In 6 states of the Ganga-Brahmaputra Plain (GB-Plain), 70.4 million people are potentially at risk from groundwater arsenic toxicity. Three additional states in the non GB-Plain are mildly arsenic affected. For arsenic with substantial cumulative exposure can aggravate the risk of cancers along with various other diseases. Clinical effects of fluoride includes abnormal tooth enamel in children; adults had joint pain and deformity of the limbs, spine etc. The affected population chronically exposed to arsenic and fluoride from groundwater is in danger and there is no available medicine for those suffering from the toxicity. Arsenic and fluoride safe water and nutritious food are suggested to prevent further aggravation of toxicity. The World Health Organization (WHO) points out that social problems arising from arsenic and fluoride toxicity eventually create pressure on the economy of the affected areas. In arsenic and fluoride affected areas in India, crisis is not always having too little safe water to satisfy our need, it is the crisis of managing the water.
Ma Y, Ma Z, Yin S, Yan X, Wang J. Arsenic and fluoride induce apoptosis, inflammation and oxidative stress in cultured human umbilical vein endothelial cells. Chemosphere. 2016 Oct 14;167:454-461. doi: 10.1016/j.chemosphere.2016.10.025.
Excessive amount of inorganic arsenic (iAs) and fluoride (F) coexist in drinking water in many regions, which is associated with high risk of vascular diseases. However, the underlying mechanisms are not well studied. The present study was to evaluate the effects of iAs and F individual or combined exposure on endothelial activation and apoptosis in vitro. Primary human umbilical vein endothelial cells (HUVECs) were exposed to 5 μM As2O3 and/or 1 mM NaF. Changes in endothelial cell apoptosis, inflammation, oxidative stress and nitric oxide (NO) production were analyzed. The results showed that iAs and/or F induced significant increase in endothelial cell apoptosis and inflammation as indicated by the increase of mRNA and protein expression of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and pentraxin 3. Furthermore, iAs and/or F exposure induced intracellular reactive oxygen species and malondialdehyde generation. Results showed iAs and/or F exposure increased the activity of NADPH oxidase (NOX) and up-regulated the mRNA expression of NOX subunits p22phox. The results indicated that activation of NOX was related to oxidative stress induced by iAs and/or F. Also, iAs and/or F reduced NO production in HUVECs. The up-regulation of inflammation genes expression and oxidative stress in iAs and F co-exposed ECs were less pronounced as compared to single F-exposed cells, which showed an antagonistic effect between iAs and F. In conclusion, endothelial activation and apoptosis induced by iAs and/or F are potential mechanisms in their vascular toxicity. Oxidative stress and impaired NO production are involved in their pro-inflammatory and pro-apoptotic effects.