Metals

Luis, Jose and Jose

= Metals =

 **Meta**l: are element that are good conductor of electric current and heat. Except for mercury, metal are solid at room temperature. Most metals are malleable. Many metals are ductile: that is, they van be drawn into thin wires. Metals are the oldest toxin known to man. They are present in the rocks and ores. Rain water dissolves them and distributes them in the environment. We get exposed to them because we use them for various purposes. Health effects due to exposure to metals could range from skin lesions to cancer. Metals can be classified into four different groups effects due to exposure to metals could range from skin lesions to cancer. Metals can be classified into four different groups.

**Categories:** · **Noble metals:** Noble metals are metals that are resistant to corrosion or oxidation**.** · **Ferrous metal:** The term "ferrous" is derived from the Latin word meaning "containing iron". · **Base metal:** In chemistry, the term base metal is used informally to refer to a metal that oxidizes or corrodes relatively easily, and reacts variably with dilute hydrochloric acid (HCl) to form hydrogen. Examples include iron, nickel, lead and zinc. · **Precious metal:** A precious metal is a rare metallic chemical element of high economic value. · **Mechanical metal:** Mechanical properties of metals include ductility, which is largely due to their inherent capacity for plastic deformation.

 **Types of metals**: Aluminum, Chromium, Cobalt, Copper, Gold, Iron, Lead, Magnesium, Manganese, Mercury, Nickel, Platinum, Silver, Tin, Titanium, Tungsten, Zinc.





**Major Toxic Metals** These are the most toxic metals, which produce multiple health effects in us. Listed below are the more important major toxic metals. Chronic Effects - Bronchitis, pneumonia, asthma, nasal itching and soreness, human carcinogen || Chronic Effects - irritation of the skin, dermatitis, skin lesion - hyper pigmentation, and Blackfoot disease (necrosis and gangrene). Inhalation causes lung cancer, ingestion causes skin, bladder and liver cancer. || Chronic Effects - anemia in children, behavioral and learning disabilities, spontaneous abortion in pregnant women, low birth weight, hyperactive, cancer-causing agent. || Chronic Effects - lung and nasal cancers ||
 * Metals || **Source of Exposure** || **Health Effects** ||
 * Chromium || Combustion of coal and crude oil, cement manufacturing, tanning industry, toner of copying machine. || Acute Effects - Dypsnea, coughing, and wheezing, skin burns, Nausea, vomiting, diarrhea.
 * Arsenic || Volcanoes, contaminated drinking water ( leaching from soil), defoliant, was used as an insecticide, and herbicides. || Acute Effects - nausea, diarrhea, abdominal pain, headache.
 * Lead || Leaded gasoline, food and soil, toys, battery manufacturing plants || Acute Effects - headache, dizziness, gastrointestinal symptoms, Death at high level of exposure.
 * Mercury || Freshwater fish caught from contaminated waters, dental filling, fluorescent lights, and thermometers, || tremors, inability to walk, convulsions, and even death at high doses, emotional changes, delayed onset of walking and talking in children. ||
 * Nickel || Food, nickel containing jewelry, cooking utensils, stainless steel kitchens, and clothing fasteners, spark plugs, batteries. || Acute Effects - Headache, vertigo, nausea, vomiting, insomnia, and irritability

**Essential Metals With Toxicity Potential** These are the metals which we need for our growth and development, but become toxic when taken more than what is required. Chronic - diabetes mellitus, affects liver functions and cardiovascular effects. || Chronic Effects - discoloration of the skin, deformation and loss of nails, loss of hair, excessive tooth decay and discoloration, and lack of mental alertness. ||
 * **Metals** || **Source of Exposure** || **Health Effects** ||
 * Iron || Mine, iron and steel workplace, during medical use. || Acute Effects - Vomiting, and ulceration of GIT, liver damage and renal failure.
 * Zinc || Foodstuff, water, and air, galvanized cans and utensils, and plastic pipes, higher amount in seafood, meat, whole grains, dairy products, and nuts. || Gastrointestinal distress and diarrhea, Inhalation could cause fever, ||
 * Selenium || Food, drinking water, metal industries, selenium-recovery processes, plastics, paints, enamels, inks, and rubber, antidandruff shampoos. || Acute Effects - irritation of the mucous membranes of lungs, pulmonary edema, severe bronchitis, and bronchial pneumonia. irritation of the mucous membranes of nose and throat, producing coughing, and nosebleeds, indigestion and nausea, headaches, dizziness, and irritation of the eyes, nausea, vomiting, diarrhea, aches, irritability, chills, and tremors.

**Metals with Toxicity Related to Medical Therapy** These are the metals which are used to treat a number of human ills, but they produce toxic effects when they accumulate in the body.
 * **Metals** || **Source of Exposure** || **Health Effects** ||
 * Aluminum || Cooking utensils, used in dialysis fluid, containers. || Irritated eyes, skin, irritates the lung tissues and causes pulmonary fibrosis producing restrictive and obstructive lung diseases, affects GIT. ||
 * Gold || Seawater, during medical use, industrial use. || Dermatitis, stomatitis ||

**Minor Toxic Metals**
 * **Metals** || **Source of Exposure** || **Health Effects** ||
 * Barium || Paints, soap, paper, and rubber, water, X-rays || Gastroenteritis, muscular paralysis, lungs and causes pneumoconiosis. ||

http://en.wikipedia.org/wiki/Metal,

http://encyclopedia2.thefreedictionary.com/Metals

Chorewar students, your treasure word is Tardigrade (TardyGrade)