Lead, a naturally occurring mineral, is a
byproduct of the refining of silver, gold and other minerals.
The earliest evidence of lead predates the Bronze and Iron Ages.
Its earliest known use was in a necklace, that was unearthed in
Turkey by archeologists, approximately 6,500 B.C..
The ancient Greeks and
Egyptians used lead in different ways. They produced lead jars and
placed vinegar in them. Then, they warmed the jars in manure piles. In
time, the acidity of the vinegar would disintegrate the lead jar
leaving behind a white powder. This white powder was the first-white
lead pigmenting, which is the basis for lead paint. The
white-pigmented lead would be used in paints for millenniums, until
its banning in the United States in 1978.
The Romans were the first known people to use lead in plumbing
systems. They used lead to line the aquifers that carried water from
far off mountains to many Roman cities. In the cities, the Romans made
rudimentary pipe and plumbing systems, which they fashioned from lead.
In fact the Latin word for "Lead" is plumbum, from which the word
"plumbing" originates. The ancient Romans also believed that the
consumption of lead pills served medicinal purposes. Today, we have
heard of, and may even possess leaded crystal vases, pitchers, and
tableware. Steuben and Waterford are known for their priceless leaded
crystal objects. Some of these can be detrimental to oneís health.
When leaded-crystal wine goblets are filled with wine, the acid
present in the wine releases the lead used in the manufacture of the
glass goblets. Another harmful product used not too long ago, was
leaded gasoline. In 1921, Generals Motors researchers determined that
when lead was added to gasoline, it would stop pinging and knocking in
Cadillac engines. From then on, until it ceased to be produced in
1995, leaded gasoline would be the standard car fuel.
Some of the most important characteristics, which made lead so
attractive are: Its low-melting point, abundance, malleability and
durability. The difficulty with it is that, once it is extracted from
the ground and processed, to any degree, it is virtually
indestructible. Once processed, lead becomes highly toxic and never
looses its toxicity. In sum, lead's toxicity is due to the
intervention of man.
Lead's toxic nature was recognized as early as 2,000 B.C.. In the 2nd
century B.C., much of Rome's affluent class suffered from lead-induced
gout. In the 17th century a German physician noticed that monks who
did not drink wine from leaded goblets were not coming down with
colic, as opposed to those who ate and drank from these vessels.
Another example of leadís toxicity was the Devon Colic, caused by the
presence of lead in cider. For centuries, workers in all steps of the
paint manufacturing process and its application, were sent to the
hospital, many times within their first month of employment, and
diagnosed with lead poisoning. This became known as the paintersí
colic. Probably, the most famous case of lead poisoning is that of
Ludwig von Beethoven.
Although much time has passed since then, the health effects from over
exposure to lead have not. Today, both adults and children suffer from
the effects of lead poisoning. Children, under the age of six, and
pregnant women are the groups most at risk. This is because the human
body is fooled by the presence of lead. Leadís toxicity to humans,
comes from its ability to mimic other biologically important metals,
such as calcium, iron and zinc, for instance. The bodily processes
don't break down, metabolize or absorb lead, as it does other
minerals. The amount of lead absorption in peopleís bodies depends on
the amount of their exposure to it. However, children and pregnant
women can absorb up to 50% of the lead they are exposed to.
A child under the age of six grows rapidly. Likewise, the human life
in the womb of a pregnant woman grows at a fast rate. Because of this,
they are more susceptible. Once inhaled or ingested, the lead moves
into the soft tissues such as the brain and kidneys, and inhibits the
growth of red blood cells. Once present, lead in a childís body can
cause learning disabilities, such as A.D.D.,(attention deficit
disorders), behavioral problems, stunted growth, impaired hearing and
kidney damage. Mental retardation and comas have also been caused by
over exposure to lead. Pregnant women transfer this lead to the fetus
and it is absorbed by the baby.
In adults, lead can increase blood pressure, cause infertility
problems, nerve disorders, muscle and joint pain, irritability and
memory problems. Lead in the blood stream is measured in micrograms of
lead per deciliter. The CDC considers any blood lead level of 10
micrograms per deciliter or greater, an elevated reading and a cause
for concern. At a reading of 20 or greater, it is considered lead
In the home, there are many ways of coming in contact with lead or its
remains. The discussion that will follow, will deal with lead in the
manufacture of paint products and lead that can be ingested from the
water we drink, however.
As a boy, I used to go to the Jersey
shore, on the southern side, of the Raritan Bridge, on the Garden
State Parkway. Along the way, I would see a large billboard,
advertising Dutch Boy Paints. The billboard portrayed a little "Dutch
Boy," in blue overalls with a blonde bowl haircut. The billboard had a
moving arm with a multi colored paint brush.
This was the logo for the National Lead Company. The portrayal of a
healthy little Dutch Boy was used to promote its lead-based paint
products for decades. The slogan read, "there is no worry when
fingerprint smudges or dirt spots when applied with Dutch Boy white
The "Dutch Process," used to create lead paint was developed in the
1600s, was very similar to the method the ancient Greeks and Egyptians
used millennium before. Lead buckles would be corroded with acid in
the presence of carbon dioxide. An acid, which was usually vinegar,
would transform the solid lead buckles, and within a few weeks a white
powder would form on the remaining lead. The yielded white powder, was
white pigmented lead. This powder was the basic element of lead paint.
The Lead Industry Association in the United States portrayed happy
children in advertisements, decades after the health risks of lead had
been revealed. It claimed that lead based paint lasted longer and it
was easier to maintain. In contrast, most European countries had
banned its use in residencies by 1921. It is estimated that by 1977,
over 50,000,000 tons of lead paint were used in American homes.
Stain, 50/50 lead and linseed oil
There existed superior alternatives to lead-based products since the
late 1800's, in titanium dioxide and lithopone. However, in 1954, the
federal government did not legislate change, due to the overbearing
pressure applied by the lead industry. A voluntary standard would
gradually restrict the use of lead in paint, but no federal
regulations would occur until 1972. The legislation, commonly known,
in the real estate industry today, would not ban the use of lead in
paint until 1978. The final cans of paint produced before the ban
would not disappear from store shelves until about 1980.
What is being done today
Many of older homes in the New England area have multiple layers of
paint. Although covered with subsequent layers of oil or latex, the
original layers of lead still pose a risk. Children at the early
stages of life, tend to place objects in their mouth. If chipping or
peeling paint condition exists in the home, they may place objects
that contain lead paint in their mouths. In performing a home
inspection, one ought to look for the presence of lead based paint on
wall surfaces. If these are undisturbed, there isnít any need for
Other risks of exposure are rubbing or sanding doors or windows, which
were originally painted with lead paint. As a door or window is opened
or closed, this sanding action releases fine dust particles in the
air, allowing them to be inhaled. A major producer of lead dust in the
air is the demolition of walls and ceilings, when rooms or houses are
remodeled. Whether sanding a surface or tearing down a wall, a
contractor should encapsulate the area, so that the dust is not
released into the air. If a contractor fails to use safe containment
procedures, both he and the homeowner can be held liable in a court of
law. When a client is concerned about the existence of lead paint in
his property, he or she should hire a licensed environmental
contractor to perform a lead inspection.
H.U.D. defines "lead paint" as, having greater than 1 microgram per
square centimeter of surface. In 1980, H.U.D. estimated that 83% of
the private and 86% of the public housing, had measurable levels of
lead. However, as far as worker exposure is concerned, any detectable
measure of lead, makes it lead paint. There are two methods that can
be used to test surfaces for lead--X-ray fluorescence or paint chip
The X-ray fluorescence inspection is performed at the house being
examined. This process involves the use of an instrument, which takes
an X-ray of the layers of paint present on a wall or painted surface.
It measures the amount of lead on a painted surface, in micrograms per
square centimeter. A qualified inspector, gathers multiple samples of
paint from each room, to get an accurate picture of the presence of
The paint chip analysis test is called Atomic Absorption. In this
test, paint chip samples are gathered at the property and sent to a
laboratory, where the percent of lead in the material sampled will be
If lead is determined to be present and clients or homeowners want to
remove any potential threat to themselves and their family, they can
take one of three courses of action. It is important to remember that
much care should be taken in the removal of lead paint. If it is done
improperly, paint removal can actually increase the level of lead
contamination in the air and the risk of exposure to the body. The
following, are measures that can be taken:
- Encapsulation--covering painted
surfaces with a special, cement-like coating, which adheres to the
lead base painted surface. This method is the least expensive
alternative. However, under certain conditions, exposure to the
original lead painted surfaces is still possible.
- Enclosure--placing a permanent
barrier, on top of the original surface, eliminates exposure. For
instance, paneling or sheet rock, placed on top or over the original
surface make contact with lead paint more difficult.
- Replacementóremoving contaminated
surfaces properly and replacing them with new surfaces.
- Keep young children away from
construction or alterations;
- Fully enclose any room, where work
is being conducted;
- Use a proper respirator;
- Use a wet-based, method of paint
removal and proper a HEPA air filtering system;
- Remove as many doors, windows, or
pieces of trim and have a paint stripping company remove the
- Maintain all existing painted
surfaces to reduce exposure to older layers of lead based paint.
Lead does not occur naturally in drinking
water. However, not unlike the ancient Romans, we, too, can be exposed
to lead through the water that we drink. This may happen when water is
in contact with the plumbing systems installed in our houses. Lead has
been used in pipe solder, to connect copper pipe joints and in the
brass and bronze plumbing fixtures in sinks, as well as in main water
piping, coming in from the street, from the local municipal water
supply company. It enters the body, primarily, from the corroding or
the wearing away of the materials containing lead in the water
distribution system. Dissolved oxygen, low pH (acidity) and low
mineral content in water are common causes of corrosion. Lead leaches
out into the water, when the water has been allowed to stand in the
pipes for any length of time.
The Environmental Protection Agency, estimates that drinking water is
the source of about 20 percent of lead exposure in Americans. The use
of lead was prohibited in 1986. Today, faucets and plumbing fixtures
may still, legally, contain 8 percent lead. Solder may contain up to
0.2%. The maximum allowable contaminant level is 15 parts per billion.
If the quantity of lead measured in drinking water exceeds this, the
following precautions are suggested:
When water stands in plumbing systems that contain lead for several
hours, the lead may dissolve into the drinking water. The first draw
of water, after it has sat in the pipes for several hours, may contain
higher quantities of lead. The homeowner ought to flush the system.
The best solution is to let the water run from the tap, until the
water being supplied gets noticeably colder; usually 15-30 seconds.
The proper steps for determining the presence of lead in drinking
water are: Select the faucet, from which the water sample is to be
drawn, six to eighteen hours in advance. If possible, use the kitchen
sink faucet, since the water for cooking and drinking is dispensed
mostly from this tap. Run cold water, at this faucet, for not less
than 10 minutes. Do not use this faucet again until the time of
sampling. The examiner will draw the first sample of water from the
faucet and fill a bottle with it.
To further test the water, a second sample should be taken. (It is my
practice, to do this.) As with the first sample, the water is to be
flushed out of the plumbing system, by running it from the faucet. The
second test provides the client with a more accurate sample of his or
her water. When the lead-contaminated water is passed through the
plumbing system, the remaining water is, then, safer to drink.
Additional information about Lead provided by the United States
Environmental Protection Agency (http://www.epa.gov/lead/)
Lead is a highly toxic
metal that was used for many years in products found in and around our
homes. Lead may cause a range of health effects, from behavioral
problems and learning disabilities, to seizures and death. Children 6
years old and under are most at risk, because their bodies are growing
Research suggests that the primary
sources of lead exposure for most children are:
- deteriorating lead-based paint,
- lead contaminated dust, and
- lead contaminated residential soil.
EPA is playing a major role in
addressing these residential lead hazards. According to the Centers
for Disease Control and Prevention (CDC), in 1978 there were 13.5
million children in the United States with elevated blood lead levels
(i.e., 10Ķg/dl). By 2002, that number had dropped to 310,000 kids.
While we still have a significant challenge, EPA is very proud of how
federal, state, tribal, and private sector partners have coordinated
efforts with the public to better protect our children.
Since the 1980's, EPA and its federal
partners have phased out lead in gasoline, reduced lead in drinking
water, reduced lead in industrial air pollution, and banned or limited
lead used in consumer products, including residential paint. States
and municipalities have set up programs to identify and treat lead
poisoned children and to rehabilitate deteriorated housing. Parents,
too, have greatly helped to reduce lead exposures to their children by
cleaning and maintaining homes, having their children's blood lead
levels checked, and promoting proper nutrition. The Agency's Lead
Awareness Program continues to work to protect human health and the
environment against the dangers of lead by developing regulations,
conducting research, and designing educational outreach efforts and
This site provides information about
lead, lead hazards, and provides some simple steps to protect your
family. For basic information start with the links to the right. For
more specific information, and to search for and download documents
use the links on the left. You can speak to an information specialist
National Lead Information Center (NLIC) at 1-800-424-LEAD