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HealthWiki > Workers' Guide to Health and Safety > APPENDIX B: Common chemicals and materials > Metals

Metals usually are solids, although mercury is a metal that is a liquid. Larger amounts of metals are harmful. Heavy metals are dangerous at any level of exposure because they accumulate in your body. Even though you might be exposed to only small amounts each day, it adds up over time to dangerous levels.

Toxic exposure to metals occurs primarily through inhaling metal dust and fumes when metals are heated, soldered, or cut. After you work with them, particles of metal or metal dust on your fingers and hands may also rub off onto food or drop into water and get into your body. Metals are most heavily used in the electronics industry in batteries, welding, recycling, and coatings. In the garment and shoe industries, metals are used in dyeing fabrics and tanning leather.

The charts include only some of the metals that exist. See Learn about chemicals used in your factory and how to find information about other metals. See the Index of chemical names to find alternative names for metals.

Prevent or reduce exposure:

  • Use ventilation systems that extract fumes and replace or dilute dirty air with clean air (see Chapter 17: Ventilation).
  • Enclose operations where possible.
  • Wear metalworking gloves when working with metals. Use a face shield when heating, soldering, or cutting metals. Wear correct respirators that fit you, especially when heating metals. All protective clothing should be clean, available each day, put on before work, and never taken home with you (see Chapter 18: Personal protective equipment).
  • Have an emergency plan that includes first aid treatment and protective equipment for spills, splashes, and accidental exposures. Keep necessary emergency supplies at the worksite, well stocked, and accessible to workers.
  • Wash your hands and face carefully before eating, drinking, or smoking.


Cadmium (Cd) CAS No. 7440-43-9

fire or explosive

Harms reproductive health

Known to cause cancer


Chromium hexavalent (Cr(VI), chromium (VI), hexavalent chromium) CAS No. 18540-29-9

fire or explosive

Known to cause cancer


Copper (Cu) CAS No. 7440-50-8

Might harm reproductive health


Lead (Pb) CAS No. 7439-92-1

Might harm reproductive health

Known to cause cancer

Mercury (Hg) CAS No. 7439-97-6

Might harm reproductive health

Nickel (Ni) CAS No. 7440-02-0

fire or explosive

Known to cause cancer

Tin (Sn) CAS No. 7440-31-5

Metals are usually solids of various colors and without odors. But some metals, such as mercury, are liquid. Others, such as chromium hexavalent can be solid or liquid. Solid chromium hexavalent is usually yellow, orange, or red. Cadmium is blue-tinged and shiny. Copper is red-orange and turns a dull, brown color when exposed to air. Lead is blue-white and turns a grey color when exposed to air. Mercury is a silver-white, heavy, and odorless liquid. Nickel is a shiny silver metal. Tin is a silvery-white solid or a grey-green powder.
Metals are used in electronic, garment, and shoe industries. Cadmium, chromium hexavalent, copper, and lead are used in electronics and in dyes in garments and shoes. Mercury, nickel, and tin are used in electronics. Nickel is also used in metal buttons on jeans, buckles, zippers, and clasps.

They can irritate your skin. Copper, mercury, and nickel cause rashes and itching. Mercury might discolor your skin grey or brown. See First Aid.


They irritate the eyes. Chromium hexavalent can damage the eyes. See First Aid.


They can irritate your nose, throat, and lungs, causing coughing, wheezing, and difficulty breathing. Breathing chromium hexavalent can cause a burning sensation. Inhaling fumes can cause dizziness and headaches. They can also create a buildup of fluid in the lungs, called lung edema. Inhaling fumes may cause “metal fume fever,” which feels like a short-lived flu. Lead can cause severe irritability, chest pain, reduced memory, disturbed sleep, and mood and personality changes. Severe mercury poisoning results in shaking, memory loss, difficulty concentrating, weight loss, personality changes, and hallucinations. See First Aid.

They can damage the gastrointestinal tract and stomach. Some signs include loss of appetite, nausea, vomiting, diarrhea, and abdominal pain. Increased salivation and metallic taste are also signs of exposure to metals. See First Aid and seek medical attention.

All metals can harm your liver, kidneys, bones, and lungs.

Cadmium and lead can cause hypertension (high blood pressure). Cadmium can also cause bronchitis, anemia, loss of the sense of smell, and discolored teeth. It can damage the baby in the womb and damage men and women’s reproductive systems. It can cause kidney, prostate, and lung cancer.

Chromium hexavalent can cause lung cancer. It can damage the respiratory tract causing nose sores and nose bleeds. It can cause skin blisters and ulcers.

Copper can cause discoloration of the skin, hair, and teeth, and may reduce fertility in men and women.

Lead may cause birth defects and harm the baby in the womb. It may reduce fertility in men and women. It can cause lung, stomach, brain, and kidney cancers.

Mercury causes permanent psychological and neurological problems. It may cause miscarriages, reduce fertility in men and women, and harm the baby in the womb.

Nickel may cause lung cancer.

Tin damages the nervous system, causing shaking and tremors.

Use Silver Shield or latex inner gloves, and nitrile or neoprene outer gloves with long cuffs (see Gloves).

Use a respirator with filters that can filter metal dust and fumes.