|
Minerals in Detail
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts | Daily Intake
BORON
Boron - chemical details
| Symbol | B |
| Atomic number | 5 |
| Atomic mass | 10.81 g.mol-1 |
| Electronegativity | 2.0 (according to Pauling) |
| Density | 2.3 g.cm-3 at 20°C |
| Melting point | 2076 °C |
| Boiling point | 3927 °C |
| Vanderwaals radius | 0.098 nm |
| Ionic radius | 0.027 nm |
| Isotopes | 2 |
| Electronic configuration | [ He ] 2s22p1 |
| Energy of first ionisation | 800.5 kJ.mol-1 |
| Energy of second ionisation | 2426.5 kJ.mol-1 |
| Energy of third ionisation | 3658.7 kJ.mol-1 |
| Discovered | 1808 - Sir Humphry Davy |
| 1808 - Joseph Gay-Lussac |
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts | Daily Intake
Boron - Description
Boron is a non metallic element and the only non-metal in group 13 of the periodic table the elements. Boron is electron-deficient, possessing a vacant
p-orbital. It has several forms, the most common of which is amorphous boron, a dark powder, unreactive to oxygen, water, acids and alkalis. It does react
with other metals to form borides. At standard temperatures boron is a very poor electrical conductor, but it becomes a better conductor the higher the
temperature.
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts | Daily Intake
Boron - Industrial applications
Boron is used in preserving wood, producing fibreglass, preservatives and detergents. For details on industrial applications and impact on the environment
see www.lenntech.com/Periodic-chart-elements/B-en.htm
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts
Boron - In natural form
Boron does not occur in nature in elemental form. It is found combined with other elements in borax, boric acid, kernite, ulexite, colemanite and borates.
Vulcanic spring waters sometime contains boric acids. Borates are mined in the US, Tibet, Chile and Turkey, with world production being about 2 million
tonnes per year.
Chemical Details | Description | Industrial Applications | In Nature | Health Impacts | Daily Intake
Boron - Impact on health
The importance of boron to human health did not even become apparent to scientists until the mid-1980's, so it isn't surprising if you know little about
this trace element.
For many centuries healers gave people who were excited the "sedative salt" boric acid, a compound containing boron. Today it has been scientifically
demonstrated that boron is important to brain function, especially in enhancing memory, cognitive function, and hand-eye coordination.
Evidence continues to mount that boron may reduce either the symptoms or incidence of arthritis. Although the connection between arthritis and boron was
first discovered in scientific studies with sheep and chickens, researchers have found a curious association between the amount of boron in the soil and
drinking water, and the incidence of arthritis in a population.
In post-menopausal females who are magnesium deficient, it has been scientifically demonstrated that 3 milligrams of boron a day added to the diet resulted
in:
1. improvements in both calcium and magnesium retention,
2. elevations in circulation serum concentrations of testosterone, and
3. elevations in circulating serum concentrations of 17-beta-estradiol (a form of estrogen).
Similar improvements can also be seen in Vitamin D deficient post-menopausal females.
Humans can be exposed to boron through fruit and vegetables, water, air and consumer products. With a regular daily intake of about 2 mg, humans have about
18 mg in their bodies naturally. When consuming large amounts of boron-containing food, the boron concentrations in the body may rise to levels that can
cause health problems. Boron can infect the stomach, liver, kidneys and brains and can eventually lead to death. When exposure to small amounts of boron
takes place irritation of the nose, throat or eyes may occur. It takes 5g of borc acid to make a person ill and 20 grams or more to put life in danger.
Eating fish or meat will not increase the boron concentrations in the body, as boron does not accumulate within the tissues of animals.
Chemical Details | Description | Industrial Applications |
In Nature | Health Impacts | Daily Intake
Boron - Recommended daily (RDA) & maximum (Limit) intake
|
| _________ |
|
_________ |
|
_________ |
|
_________________ |
|
_________________ |
| (Maximum) |
|
Risk free |
|
intake? |
| |
Food sources? |
| |
Result of overdose? |
| Age Group |
| |
RDA |
| |
Limit |
| |
|
| |
|
| _________ |
| |
_________ |
| |
_________ |
| |
_________________ |
| |
_________________ |
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 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
(mg/d)
ND
ND
3
6
11
17
20
20
20
20
11
17
20
20
20
20
17
20
20
17
20
20 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Avocado
Fruit
Fruit Juice
Legumes
Milk
Peanut
Peanut Butter
Potatoes |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Reproductive and developmental effects as observed in animal studies. |
| _________ |
| |
_________ |
| |
_________ |
| |
_________________ |
| |
_________________ |
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.3, 4, 5, 6
Limit = The maximum level of daily nutrient intake from all sources that is highly likely to pose no risk of adverse effects.3, 4, 5, 6
References:
- Shils, M.E. & Young, V.R. (1988). Modern Nutrition in Health and Disease, 7th Edition. Lea & Febiger: Philadelphia.
- Schauss, A.G. (1996). Minerals, Trace Elements and Human Health. Life Sciences Press: Tacoma, (WA).
- 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.
|
