Zhao J, Guo H, Ma J, Shen Z. Effect of Fluoride on Arsenic Uptake from Arsenic-Contaminated Groundwater using Pteris vittata L. International Journal of Phytoremediation. 2015;17(4):355-62. doi: 10.1080/15226514.2013.837028.
High-arsenic groundwater in inland basins usually contains high concentrations of fluoride. In the present study, the effects of fluoride on arsenic uptake by Pteris vittata and on arsenic transformation in growth media were investigated under greenhouse conditions. After P. vittata was hydroponically exposed to 66.8 μM As (V) in the presence of 1.05 mM F(-) in the form of NaF, KF, or NaF+KF for 10 d, no visible toxicity symptoms were observed, and there were not significant differences in the dry biomass among the four treatments. The results showed that P. vittata tolerated F(-) concentrations as high as 1.05 mM but did not accumulate fluoride in their own tissues. Arsenic uptake was inhibited in the presence of 1.05 mM F(-). However, in hydroponic batches with 60 μM As (III) or 65 μM As (V), it was found that 210.6 and 316.0 μM F(-) promoted arsenic uptake. As(III) was oxidized to As(V) in the growth media in the presence and absence of plants, and F(-) had no effect on the rate of As(III) transformation. These experiments demonstrated that P. vittata was a good candidate to remediate arsenic-contaminated groundwater in the presence of fluoride. Our results can be used to develop strategies to remediate As-F-contaminated water using P. vittata.
Paper is here (fee).
A human is not a large rat physiologically (some maybe socially?). So the findings of this study may or may not apply to humans. But even so, properly qualified, effects observed in animal tests may be expected to occur in humans. So said the National Academy of Sciences circa 1977.
Jiang C, Zhang S, Liu H, Guan Z, Zeng Q, Zhang C, Lei R, Xia T, Wang Z, Yang L, Chen Y, Wu X, Zhang X, Cui Y, Yu L, Wang A. Low glucose utilization and neurodegenerative changes caused by sodium fluoride exposure in rat’s developmental brain. NeuroMolecular Medicine, Vol 16(1), Mar, 2014. pp. 94-105.
Fluorine, a toxic and reactive element, is widely prevalent throughout the environment and can induce toxicity when absorbed into the body. This study was to explore the possible mechanisms of developmental neurotoxicity in rats treated with different levels of sodium fluoride (NaF). The rats’ intelligence, as well as changes in neuronal morphology, glucose absorption, and functional gene expression within the brain were determined using the Morris water maze test, transmission electron microscopy, small-animal magnetic resonance imaging and Positron emission tomography and computed tomography, and Western blotting techniques. We found that NaF treatment-impaired learning and memory in these rats. Furthermore, NaF caused neuronal degeneration, decreased brain glucose utilization, decreased the protein expression of glucose transporter 1 and glial fibrillary acidic protein, and increased levels of brain-derived neurotrophic factor in the rat brains. The developmental neurotoxicity of fluoride may be closely associated with low glucose utilization and neurodegenerative changes.
Arctic sea ice extent is cyclical. Now it is returning to past levels which is just the opposite of the global warming predictions. Here for more….
Source: Real Science
Penman, Allan D. Brackin, Bruce T. Outbreak of acute fluoride poisoning caused by a fluoride Overfeed, Mississippi, 1993 Public Health Reports. Sep/Oct97, Vol. 112 Issue 5, p403
Describes an outbreak of acute fluoride poisoning toxicity in August 1993 in a Mississippi community. Number of restaurant-associated cases of gastrointestinal illness in Mississippi; Unadjusted and adjusted relative risks of acute fluoride poisoning among restaurant patrons in 1993; Diagram of fluoridation system and faults at a water treatment plant in Mississippi.
Posted in Fluoride
During the prior week Pope Francis’s announcement to support a UN “climate change” accord in Paris next year received a lot of attention (e.g. here). The announcement provided the press an opportunity to slap the “deniers” in the face. Unfortunately, the Pope is off-base on “climate change” as it relates to poor communities.
Changes in climate (regardless of cause) affect ALL communities in a particular region whether they are large or small, rich or poor. That is the reality….
So what’s the real problem? Why are poor communities and poor countries poor? No jobs? No economic development? No infrastructure? And what is necessary to change all of these? Affordable energy. Affordable energy is a prerequisite for having sustainable community.
How many people will die as a result of the overemphasis on preventing “climate change”, which cannot be stopped, with ineffective UN and government policies and regulations that drive up the cost of energy without solving the “climate change” problem?
It is not possible even with the efforts undertaken here to avoid the ecologic fallacy. The design and extent of this study is insufficient to make any statement about bone mineral measures of “most US adolescents in fluoridated areas”. But with the US health system in disarray from Obamacare such overstatement of results will go un-noticed. Opposition to communal fluoridation will continue. This study and others like it simply cannot show fluoride addition to drinking water is safe and effective.
Levy SM, Warren JJ, Phipps K, Letuchy E, Broffitt B, Eichenberger-Gilmore J, Burns TL, Kavand G, Janz KF, Torner JC, Pauley CA. Effects of life-long fluoride intake on bone measures of adolescents: a prospective cohort study. Journal Of Dental Research 2014 Apr; Vol. 93 (4), pp. 353-9
Controversy persists concerning the impact of community water fluoridation on bone health in adults, and few studies have assessed relationships with bone at younger ages. Ecological studies of fluoride’s effects showed some increase in bone mineral density of adolescents and young adults in areas with fluoridated water compared with non-fluoridated areas. However, none had individual fluoride exposure measures. To avoid ecological fallacy and reduce bias, we assessed associations of average daily fluoride intake from birth to age 15 yr for Iowa Bone Development Study cohort members with age 15 yr dual-energy x-ray absorptiometry (DXA) bone outcomes (whole body, lumbar spine, and hip), controlling for known determinants (including daily calcium intake, average daily time spent in moderate-to-vigorous intensity physical activity, and physical maturity). Mean (SD) daily fluoride intake was 0.66 mg (0.24) for females and 0.78 mg (0.30) for males. We found no significant relationships between daily fluoride intake and adolescents’ bone measures in adjusted models (for 183 females, all p values ≥ .10 and all partial R(2) ≤ 0.02; for 175 males, all p values ≥ .34 and all partial R(2) ≤ 0.01). The findings suggest that fluoride exposures at the typical levels for most US adolescents in fluoridated areas do not have significant effects on bone mineral measures.
Qian Y, Wu M, Wang W, Chen B, Zheng H, Krasner SW, Hrudey SE, Li X.Determination of Fourteen Nitrosamines at ng/L levels in Drinking Water. Anal Chem. 2014 Dec 19.
N-nitrosamines, probable human carcinogens, are a group of disinfection byproducts (DBPs) under consideration for drinking water regulation. Currently, no method can determine trace levels of alkyl and tobacco-specific nitrosamines (TSNAs) of varying physical and chemical properties in water by a single analysis. To tackle this difficulty, we developed a single solid-phase extraction (SPE) method with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for the determination of 14 nitrosamines of health concern with widely differing properties. We made a cartridge composed of vinyl/divinyl benzene polymer that efficiently concentrated the 14 nitrosamines in 100 mL of water (in contrast to 500 mL in other methods). This single SPE-HPLC-MS/MS technique provided calculated method detection limits (MDLs) of 0.01-8.3 ng/L and recoveries of 53-93% for the 14 nitrosamines. We have successfully demonstrated that this method can determine the presence or absence of the 14 nitrosamines in drinking water systems (eight were evaluated in Canada and the U.S.), with similar occurrence to that in other surveys. N-Nitrosodimethylamine (NDMA), N-nitrosodiphenylamine (NDPhA), and the TSNA 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) were identified and quantified in authentic drinking water. Formation potential (FP) tests demonstrated that NDMA and TSNA precursors were present in (1) water samples in which tobacco was leached and (2) wastewater-impacted drinking water. Our results showed that pre-chlorination or ozonation destroyed most of the nitrosamine precursors in water. Our new single method determination of alkyl nitrosamines and TSNAs significantly reduced the time and resource demands of analysis and will enable other studies to more efficiently study precursor sources, formation mechanisms, and removal techniques. It will be useful for human exposure and health risk assessments of nitrosamines in drinking water.
Posted in NDMA