| LEAD
Also known as: Lead flake, Orow (polish), Pb, CI pigment Metal 4
Chemical reference number (CAS): 7439-92-1
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WHAT IS LEAD?
Lead is a naturally occurring toxic metal. It may be found in its pure form or in
combination with other minerals. Lead has no nutritional value, but is very valuable in
manufacturing. In industry, lead is used in the production of batteries, solder, paints,
ammunition, sheet metal, and other metal alloys.
Lead is often found in paint sold before 1978. Since 1978, paint sold for residential
use can contain no more than 600 parts per million lead. Most lead is now used to
manufacture car batteries. Other lead sources include bullets, fishing weights, curtain
weights, some glazed ceramics, and plumbing solders made before 1986. Less common sources
include the solder on some imported canned goods, cosmetics (ceruse, surma or kohl), folk
medicines (azarcon, Greta, Pay-loo-ah), and paints used on steel structures such as
bridges or water towers.
HOW ARE PEOPLE EXPOSED TO LEAD?
Drinking/Eating: People can be exposed to lead when they ingest
contaminated water or foods that are stored in lead-glazed ceramic dishware.
The most common route for lead exposure in children is by mouth. Young children like to
put their fingers, toys and other objects in their mouths. They especially like to do this
when they are teething. Dust or chips from lead-based paint can easily poison pre-school
aged children.
Less common, but more dangerous exposures occur when children eat paint chips or soil
containing lead. Lead tastes sweet, which makes it attractive to children, especially to
hungry children.
People who work with lead products can expose their family to lead. Exposure may occur
if they bring lead-covered work clothes home for laundering or wear their contaminated
clothes around the home.
Lead can dissolve from the solder of water pipes, particularly if the water is heated
or naturally soft. Use cold water when cooking or when preparing infant formula. Hot water
tends to dissolve lead from solder in pipes.
Breathing: Lead in the air results from emissions from smelting
operations or waste incinerators. Soil and dust may contain fine lead particles created by
car exhaust (when burning leaded gasoline) or from sanding or grinding old lead paint.
Soldering leaded glass, firing ceramic glazes that contain lead, melting lead or burning
old lead paint can release hazardous metal fumes.
Touching: Lead is not readily absorbed through the skin.
DO STANDARDS EXIST FOR LEAD IN DRINKING WATER?
State and federal drinking water standards for lead are set at 15 parts per billion
(ppb). We suggest you stop drinking water containing more than 15 parts per billion (ppb)
of lead. If your plumbing system contains lead solder or lead pipes, running the cold
water two to three minutes before using the water will usually lower the lead in the water
to safe levels.
WHAT ARE THE SYMPTOMS OF LEAD POISONING?
The average person in the U.S. has less than 5 micrograms of lead per deciliter (dL) of
blood.
Lead is a tricky poison to identify. At low or moderate levels of exposure, children
often have no symptoms or they may have general symptoms like those of other common
childhood illnesses. Health effects get more severe as blood lead levels increase. The
following information describes the effects on human health at various levels of lead in
blood.
Low Levels:
10-35 mircograms/dL in Children or 10-40 micrograms/dL in Adults. Usually there are no
visible symptoms. These levels, if they persist, can cause subtle learning and behavior
problems in children.
Moderate Levels:
35-50 micrograms/dL in Children or 40-60 micrograms/dL in Adults. There may be no
symptoms. If symptoms are there, they may include general fatigue, irritability,
difficulty concentrating, tremors, headaches, abdominal pain, anemia, vomiting, weight
loss and/or constipation. These can be mistaken for other illnesses. Adults with elevated
blood lead levels are also at risk for high blood pressure and kidney problems.
High Levels:
Over 50 micrograms/dL in Children or over 60 micrograms/dL in Adults. There may
be no symptoms, or there may be symptoms as listed above under "Moderate." At
very high levels, symptoms can include convulsions, paralysis, coma or death.
In general, chemicals affect the same organ systems in all people who are exposed.
However, the seriousness of the effects may vary from person to person. It is also
important to consider the length of exposure to the chemical; the amount of chemical
exposure; and whether the chemical was inhaled, touched, or eaten.
The effects of lead on adults are generally reversible. The effects on children under
six years of age can be more severe and probably cannot be reversed. Children absorb up to
50% of the lead they eat, while adults absorb only about 10%. The nervous systems of
children are more sensitive to damage from lead. The general health and nutrition of the
exposed person, including iron or calcium deficiency and sickle cell disease, can affect
the severity of symptoms.
CAN A MEDICAL TEST DETERMINE EXPOSURE TO LEAD?
A blood test can measure recent exposure to lead.
Seek medical advice if you have any symptoms that you think may be related to chemical
exposure.
Children with blood lead levels as low as 10 micrograms/dL can experience subtle
learning and behavior problems. They should be periodically re-tested to see if the levels
are going down or up. Their families should find out ways to reduce childhood lead
exposure.
Children with blood lead levels of 20 micrograms/dL or higher should be evaluated by a
physician and have their environments assessed for lead hazards.
Children with blood levels of 45 micrograms/dL or higher should have chelation therapy
to remove lead from their bodies.
Children with blood levels of 70 micrograms/dL or higher can have serious health
problems. They should be immediately admitted to a medical treatment facility.
(PPH 4603 Revised 3/2000)
This fact sheet summarizes information about this chemical and is not a complete
listing of all possible effects. It does not refer to work exposure or emergency
situations.
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