Fluoride is an element found in rocks and minerals. 氟化物是岩石和矿石中含的一种元素。
Since then, many studies have confirmed the value of fluoride. 从那以后,许多研究都证实了氟化物的价植。
fluoride
[ noun ] a salt of hydrofluoric acid <noun.substance>
Fluoride \Flu"or*ide\ (? or ?; 104), n. [Cf. F. fluoride.] (Chem.) A binary compound of fluorine with another element or radical.
{Calcium fluoride} (Min.), fluorite, {CaF2}. See {Fluorite}.
It is known chemically as polyvinylidene fluoride and is sold under the trade name Kynar.
But a vocal minority condemns fluoride as an industrial waste product that not only mottles teeth, but kills thousands of people every year.
The high doses contained fluoride in far greater amounts than humans are exposed to in toothpaste and water, Brown said.
It then diffuses sodium fluoride through a thin membrane into the saliva for six months.
In Kracow, for example, sulfur, carbon monoxide and fluoride fumes are contributing to the destruction of the city's distinctive Gothic architecture.
Everyone was cheering." That included Leland Gershell, who spent the last 18 months designing and performing an experiment that linked the fluoride content of dental patients' saliva with their susceptibility to cavities.
On average, volcanoes release a total of up to 15.4 million tons of hydrogen chloride and hydrogen fluoride to the atmosphere a year, but less than a tenth reaches the stratosphere, they calculated.
But the Chicago-based ADA said Tuesday the public should not fear sodium fluoride because humans ingest much smaller amounts of the chemical.
High doses of stannous fluoride can cause gastrointestinal upset and vomiting, which could limit the amount ingested and the adverse effects, the FDA said.
Four rats in another group of 80 developed cancer _ three osteosarcomas _ after drinking fluoride at 79 parts per million during the period.
That helps alleviate gastrointestinal discomfort and allows the fluoride to be absorbed slowly into the blood, at an effective but not toxic rate, Pak said.
The most direct competition for Arm & Hammer will come from Peak, a Colgate toothpaste that contains baking soda but doesn't have fluoride.
In those days, right-wingers believed that water treated with fluoride was a dangerous left-wing conspiracy; Ms. O'Connor's newsletter cheerfully assured everyone that fluoride had not been added to the train's water supply.
In those days, right-wingers believed that water treated with fluoride was a dangerous left-wing conspiracy; Ms. O'Connor's newsletter cheerfully assured everyone that fluoride had not been added to the train's water supply.
Uses for polyvinylidene fluoride, sold by Pennwalt as Kynar plastic resin, include coating electrical wires and lining pipes in chemical plants.
If the trend away from tap water lowers fluoride intake, supplements may be in order, writes Sheila McGuire, D.D.S., Harvard Dental School.
The reduction in dental caries in the decades since fluoride was introduced is substantial.
A further 2m live in areas with naturally high fluoride levels.