Henri Moissan

9

Fluorine F 18 decays by positron ,(β+) emission and has a half-life of 109.7 minutes. The principal photons useful for diagnostic imaging are the 511 keV gamma photons, resulting from the interaction of the emitted positron with an electron (Table 1).

Fluorine F 18 decays by positron (β+) emission and has a half-life of 109.7 minutes.

gamma radiation

The name fluorspar is derived from the Latin fluere, “to flow.” The mineral subsequently proved to be a source of the element, which was accordingly named fluorine.

If fluorine is absorbed too frequently, it can cause teeth decay, osteoporosis and harm to kidneys, bones, nerves and muscles. Fluorine gas is released in the industries. This gas is very dangerous, as it can cause death at very high concentrations. At low concentrations it causes eye and nose irritations.

Sources of Fluoride

Approximately 99% of the fluoride in the human body is found in bones and teeth. Fluoride is incorporated into tooth and bone by replacing the hydroxyl ion in hydroxyapatite to form fluorohydroxyapatite.

Coffee contains 0.10–0.58 mg/L of fluoride in the infusion solution and 0.15–0.56 mg/L in instant pack.

Pork, beef, turkey, chicken, fish, shellfish, and eggs contain high amounts of selenium. Some beans and nuts, especially Brazil nuts, contain selenium.

Vegetables: all vegetables — cruciferous vegetables are fine to eat in moderate amounts, especially when cooked. Fruits: all other fruits, including berries, bananas, oranges, tomatoes, etc. Gluten-free grains and seeds: rice, buckwheat, quinoa, chia seeds, and flax seeds.

Selenium deficiency can cause Keshan disease (a type of heart disease) and male infertility. It might also cause Kashin-Beck disease, a type of arthritis that produces pain, swelling, and loss of motion in your joints.

What are the symptoms?

• infertility in men and women.
• muscle weakness.
• fatigue.
• mental fog.
• hair loss.
• weakened immune system.

The safe upper limit for selenium is 400 micrograms a day in adults. Anything above that is considered an overdose.

High Selenium Leads to Weight Gain. Chemist Wayne Chris Hawkes prepares to test a rice sample from China for selenium content. Meals rich in selenium may slow the rate at which your body burns calories, ARS researchers report.

Spinach, cooked from frozen, will provide you with about 11 mcg of selenium per cup. It’s also packed full of folic acid and vitamin C.

Best selenium capsules

• Klaire Labs Seleno Met. SHOP NOW AT Amazon. Price: $$
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Most of our common foods, however, contain a very low level of selenium; for example, natural garlic contains <0.05 μg Se/g garlic (32). The selenium content of plants is dependent upon the amount of selenium in the soil.

Brazil nuts are the most potent source of selenium available. Just one nut contains 95 micrograms, almost twice your daily requirement. However, it’s important to moderate your portions to the recommended amounts.