Fluoride levels in seven commercial phosphate fertilizers (four single superphosphate samples, two diammonium phosphate samples, and one ammonium nitrophosphate sample) were analyzed independently at three laboratories employing the techniques of ion chromatography and ion-selective electrode. The results were consistent for aqueous solutions containing 100?mg?L?1 (ppm) of fertilizer. The average values of fluoride from four different studies varied from 0.140?±?0.006–1.33?±?0.158% (w/w) for the seven fertilizer samples. The [P2O5]/[F] ratios (w/w) were computed for all the seven samples and the values were in the range of 13.79–328.57. By comparing these values with the average [P2O5]/[F] ratio in phosphate rock, it was inferred that 3–75% of fluoride originally present in rock remained in the fertilizers. IR spectral data revealed a small peak at 716?cm?1 – indicative of SiF62? – in the sample containing lowest fluoride which may be on account of fluoride stripping of intermediate phosphoric acid with reactive silica in this case. Considering 15 MMT (million metric tons) of annual consumption of phosphate fertilizers in India, the incremental load of fluoride in agricultural fields was estimated to be 127,650?±?14,550 MTy?1 based on the grand average fluoride content of 0.851?±?0.097% (w/w). While a part of this fluoride would likely get discharged into oceans through run-off, the remainder may persist in the soil, some amount may accumulate in vegetation, and a part might find its way into fresh water bodies, thereby aggravating the fluoride problem in the Country. The problem of non-point source pollution can be reduced by eliminating fluoride at source, and utilizing the recovered fluoride as feedstock. This could, in principle, satisfy the entire requirement of the fluorochemicals industry in India. Environmental costs need to be factored in while making an assessment of the viability of fluoride recovery and reuse in this manner compared to production from virgin sources of fluoride.
Fluoride in the diet of 2-years-old children
OBJECTIVES: This study aimed to calculate the fluoride concentrations of commonly consumed foods and beverages for 2-years-old children utilizing market basket information for the US Midwest region. METHODS: Total Diet Study food lists were cross-referenced with National Health and Nutrition Examination Survey-What We Eat in America data to determine the foods
Fluorosis induced by drinking brick tea
Fluorosis in China has been known to be induced by two main causes. One is water-dependent fluorosis caused by a long-time consumption of high-fluoride (F) containing water. The other is called "coal-burning type fluorosis", caused by inhalation of air polluted by coal smoke and/or ingestion of food exposed to coal
Fluoride ingestion in children: a review of 87 cases.
All cases of fluoride ingestion in children younger than 12 years old reported to the Rocky Mountain Poison Center between January 1 and December 31, 1986, were retrospectively reviewed. Eighty-seven cases were identified. Eighty-four cases involved accidental ingestion of dental fluoride products in the home (tablets, drops, rinses) in children
Potential fluoride exposure from selected food crops grown in high fluoride soils in the Makueni County, south-eastern Kenya.
Makueni County, located in south-eastern Kenya, faces challenges such as limited potable water and restricted food supplies as the result of semi-aridity. High fluoride (F) concentrations have been reported in drinking water with resultant dental fluorosis affecting the local population. To determine the potential F exposure through the consumption of
Associations of fluoride intake with children's bone measures at age 11.
BACKGROUND: Relationships between fluoride intake and bone health continue to be of interest, as previous studies show conflicting results. OBJECTIVES: The purpose is to report associations of fluoride intake with bone measures at age 11. METHODS: Subjects have been participating in the ongoing Iowa Fluoride Study/Iowa Bone Development Study. Mothers were recruited
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