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Minerals in Detail
Chemical Details | Description | Industrial Applications |
In Nature | Health Impacts | Daily Intake
ZINC
Zinc - chemical details
| Symbol | Zn |
| Atomic number | 30 |
| Atomic mass | 65.37 g.mol-1 |
| Electronegativity | 1.6 (according to Pauling) |
| Density | 7.11 g.cm-3 at 20°C |
| Melting point | 420 °C |
| Boiling point | 907 °C |
| Vanderwaals radius | 0.138 nm |
| Ionic radius | 0.074 nm (+2) |
| Isotopes | 10 |
| Electronic configuration | [ Ar ] 3d10 4s2 |
| Energy of first ionisation | 904.5 kJ.mol-1 |
| Energy of second ionisation | 1723 kJ.mol-1 |
| Energy of third ionisation | 3833 kJ·mol-1 |
| Standard potential | - 0.763 V |
| Discovered | 1746 - Andreas Marggraf |
Chemical Details | Description | Industrial Applications |
In Nature | Health Impacts | Daily Intake
Zinc - Description
Zinc is a lustrous bluish-white metal. It is found in group IIb of the periodic table. It is brittle and crystalline at ordinary temperatures, but it
becomes ductile and malleable when heated between 110°C and 150°C. It is a fairly reactive metal that will combine with oxygen and other non-metals, and
will react with dilute acids to release hydrogen.
Chemical Details | Description | Industrial Applications |
In Nature | Health Impacts | Daily Intake
Zinc - Industrial applications
The primary uses of Zinc are in galvanising and pigmentation. There are many others however. For details on
industrial applications and impact on the environment see www.lenntech.com/Periodic-chart-elements/Zn-en.htm
Chemical Details | Description | Industrial Applications |
In Nature | Health Impacts | Daily Intake
Zinc - In natural form
Zinc occurs naturally in air, water and soil, but zinc concentrations are rising unnaturally, due to addition of zinc through human activities. Most zinc is
added during industrial activities, such as mining, coal and waste combustion and steel processing. Some soils are heavily contaminated with zinc, and these
are to be found in areas where zinc has to be mined or refined, or were sewage sludge from industrial areas has been used as fertilizer.
Zinc is the 23rd most abundant element in the Earth's crust. The dominant ore is zinc blende, also known as sphalerite. Other important zinc ores are
wurzite, smithsonite and hemimorphite. The main zinc mining areas are Canada, Russia, Australia, the USA and Peru. World production exceeds 7 million tonnes
a year, and commercially exploitable reserves exceed 100 million tonnes. More than 30% of the world's need for zinc is met by recycling.
Chemical Details | Description | Industrial Applications |
In Nature | Health Impacts | Daily Intake
Zinc - Impact on health
Zinc is a trace element that is essential for human health. When people absorb too little zinc they can experience a loss of appetite, decreased sense of
taste and smell, slow wound healing and skin sores. Zinc-shortages can even cause birth defects.
Is an essential trace mineral occurring in the body in larger amounts than any other trace element except iron. It is present in all tissues. Zinc is known
for its ability to fight disease and to protect the immune system. It is involved in the Krebs cycle and energy production. More recently, blindness in the
elderly has been found to be arrested by zinc. It is also credited with increasing male sex drive and potency because of its ability to regulate
testosterone in the prostate.
It is a key factor in prostate gland function and reproductive organ growth. It is estimated that 3,000 of the hundreds of thousands of proteins in the
human body contain zinc prosthetic groups, one type of which is the so-called zinc finger. In addition, there are over a dozen types of cells in the human
body that secrete zinc ions, and the roles of these secreted zinc signals in medicine and health are now being actively studied. Zinc ions are now
considered to be neurotransmitters. Cells in the salivary gland, prostate, immune system and intestine use zinc signalling.1
Zinc is also involved in olfaction (the ability to smell): the olfactory receptors contain zinc binding sites and a deficiency in zinc causes anosmia.
Zinc is an activator of certain enzymes, such as carbonic anhydrase. Carbonic anhydrase is important in the transport of carbon dioxide in vertebrate blood.
It is also required in plants for leaf formation, the synthesis of indole acetic acid (auxin) and anaerobic respiration (alcoholic fermentation).2
Zinc is a good lewis acid, making it a useful catalytic agent in hydroxylation and other enzymatic reactions. Also Zinc has a flexible coordination geometry,
allowing enzymes using Zinc to rapidly shift conformations and perform biological reactions.3
Chemical Details | Description | Industrial Applications |
In Nature | Health Impacts | Daily Intake
Zinc - Recommended daily & maximum intake
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Risk free |
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intake? |
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Food sources? |
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Result of overdose? |
| Age Group |
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RDA |
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Limit |
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Infants
0-6 mo
7-12 mo
Children
1-3 y
4-8 y
Males
9-13 y
14-18 y
19-30 y
31-50 y
50-70 y
> 70 y
Females
9-13 y
14-18 y
19-30 y
31-50 y
50-70 y
> 70 y
Pregnancy
< 19 y
19-30 y
31+ y
Lactation
< 19 y
19-30 y
31+ y |
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(mg/d)
2.0
3.0
3.0
5.0
8.0
11.0
11.0
11.0
11.0
11.0
8.0
9.0
8.0
8.0
8.0
8.0
12.0
11.0
11.0
13.0
12.0
12.0 |
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(mg/d)
4.0
5.0
7.0
12.0
23.0
34.0
40.0
40.0
40.0
40.0
23.0
34.0
40.0
40.0
40.0
40.0
34.0
40.0
40.0
34.0
40.0
40.0 |
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Grains
Red meat
Some seafood |
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Reduced copper availability |
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Explanations:
ND = Not determinable. There is either insufficient data on adverse effects and/or concern with the body's ability to handle excess amounts. In most
instances it is wise not to supplement for this particular element, but to rely on diet to provide sufficient quantities.
RDA = Recommended Dietary Allowance. May be used as a goal for daily intake. RDAs are set at a level that should meet the needs of 97-98% of all individuals.4, 5, 6, 7
Limit = The maximum level of daily nutrient intake from all sources that is highly likely to pose no risk of adverse effects.4, 5, 6, 7
References:
- Hershfinkel, M., Silverman, W., & Sekler, I. (2007). The Zinc Sensing Receptor, a Link Between Zinc and Cell Signaling. Mol Med 13 (7-8): 331-336.
- Gadallah, M. (2000) Effects of indole-3-acetic acid and zinc on the plant growth, osmotic potential and soluble carbon and nitrogen components of soybean plants growing under water deficit. J. Arid Env., Vol 44, 4, pp. 451-467.
- Stipanuk, M. (2006). Biochemical, Physiological & Molecular Aspects of Human Nutrition, Elsevier Health Sciences: Amsterdam, pp. 1043-1067.
- Standing Committee on the Scientific Evaluation of Dietary Reference Intakes (1997). Dietary Reference Intakes for Calcium, Phosphorous, Magnesium, Vitamin D, and Fluoride. Food and Nutrition Board: Institute of Medicine.
- Standing Committee on the Scientific Evaluation of Dietary Reference Intakes (1998). Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6,
Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Food and Nutrition Board: Institute of Medicine.
- Standing Committee on the Scientific Evaluation of Dietary Reference Intakes (2000). Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Food and Nutrition Board: Institute of Medicine.
- Standing Committee on the Scientific Evaluation of Dietary Reference Intakes (2001). Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Food and Nutrition Board: Institute of Medicine.
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