Lead has been a part of human civilization for thousands of years, but it's been a mixed blessing -- exposure to high levels of the metal can cause a raft of health problems. And if you think that safety regulations are protecting you and your family from lead poisoning, think again.

Basic Facts About Lead

Lead is a metallic element that's found all over the world, on every continent, and is usually mined as an ore with zinc, copper, silver or other heavy metals.

Because lead has a relatively low melting point, it could be separated from ore by even the most primitive societies: Archaeologists believe lead has been in use since around 6500 B.C.

Lead also is a relatively soft, heavy metal that can be hammered into pots, jewelry, cookware, plumbing and other implements. In fact, the word "plumbing" has its roots in the Latin name for lead, "plumbum." This is also the source of lead's symbol on the periodic table of elements: Pb.

But its usefulness in plumbing and cookware has a dark side: lead poisoning. Wine fermented or stored in lead containers, and food cooked in lead pots, contain dangerously high levels of the element. Though it was once believed the use of lead pipes contributed to the downfall of the Roman Empire, that theory is now largely disproved. Lead poisoning was, however, not uncommon in the ancient world, and it's distressingly common even today.

The Industrial Revolution contributed to an enormous jump in the mining, smelting and distribution of lead.

Lead was widely used in the soldering for canned foods, in paints -- especially white interior paints -- and in leaded gasoline. It's also used in batteries, lead ammunition, X-ray shields and hundreds of other industrial uses.

Though strict regulation has eliminated most lead paints and leaded gasoline around the world, its use was so pervasive that lead is now found in soils worldwide, and people alive today have much higher levels of lead in their blood than people living in pre-industrial societies. And even in developed nations like the United States, most buildings built before 1978 -- including schools, churches, homes and offices -- contain some lead paint.

Lead can also be found in cosmetics like lipstick and hair coloring, drinking water, certain glazed ceramics, toys and game pieces, solder in some cans, artificial Christmas trees, bullets, and in the meat of animals that are hunted with bullets that contain lead. In many cases, levels of lead are higher in items like toys and ceramics that are imported from developing countries.

Warning Signs of Lead Poisoning

Lead poisoning was once called "painter's colic" because it was so common among people who worked daily with lead paints. Even the ancients recognized that lead seemed to contribute to paralysis and other conditions.

Symptoms of lead poisoning are difficult to specify because different levels of exposure to lead cause different symptoms over time; the differences can be especially pronounced between children and adults. In adults, symptoms of lead exposure may include insomnia, high blood pressure, disturbed mental functioning, numbness or tingling in feet and hands, headache, abdominal pain, memory loss or mood disorders.

Among children, lead poisoning can cause irritability, loss of appetite, weight loss, fatigue, stomach pain, nausea, constipation or learning difficulties. At very high levels of exposure, lead poisoning in kids and adults can result in wrist or foot drop, difficulty concentrating, partial paralysis, delirium, seizures or encephalopathy (characterized by brain swelling).

Lead Poisoning: Take Action

If it's caught early, lead poisoning can be treated with therapies that draw lead out of the bloodstream. There may be no way, however, to reverse damage caused by exposure to high levels of the heavy metal.

Preventing lead exposure is therefore critical. There are some simple steps that everyone can take to prevent lead poisoning, especially in families with young children (who are particularly susceptible to it). The following guidelines are adapted from information provided by the EPA and the CDC:

• Use only cold water to prepare food and drinks (hot water absorbs more lead by sitting in pipes and water heaters longer).
• Flush all water outlets used for drinking or food preparation.
• Clean outlet screens or aerators on faucets on a regular basis.
• Keep your home clean and dust-free.
• Wipe up any paint chips or visible dust with a wet sponge or rag. Clean dust around areas where there is friction and dust can be generated, such as doors, windows, and drawers.
• Wash children's hands, bottles, pacifiers and toys often.
• Teach children to wipe and remove their shoes and wash hands after playing outdoors.
• Ensure that your family members eat well-balanced meals. (Lead interferes with some of the body's basic functions, and our bodies can't tell the difference between lead and calcium, a mineral that strengthens bones. Children with healthy diets absorb less lead.)
• Make sure any contractors working in your home are "Lead-Safe Certified."
• Talk to your state or local health department about testing paint and dust from your home for lead.
• Make sure children do not have access to peeling paint or chewable surfaces painted with paint that may contain lead.
• Pregnant women and children should not be present in housing built before 1978 that is undergoing renovation.