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Lead Poisoning
Contents
1. Introduction
2. ADME of Lead
3. Definition of Lead Poisoning
4. Main effect of Lead
5. Causes lead poisoning
5.1 Enzymes
5.2 Neurons
5.3 Some potential sources of exposure
5.4 Some cases of lead poisoning have
been traced to the use of certain
traditional medicines
6. Sign & Symptoms of lead poisoning
6.1 Acute poisoning
6.2 Chronic poisoning
6.3 Symptoms in children
6.4 Symptoms in newborns
6.5 Symptoms in adults
7. Lead Encephalopathy
8. Risk factors of lead poisoning
8.1 Factors that may increase your risk
of lead poisoning
8.2 Others risk for lead poisoning
9. Differential diagnosis of lead
poisoning
10. Investigations of lead poisoning
10.1 Laboratory tests
10.2 Radio-imaging
11. Management
12. Short note on chelation therapy
12.1 Chelation therapy
12.2 Chelation therapy used for
12.3 Chelation therapy may be used in
case of lead poisoning
12.4 Justification of safety of chelation
therapy
12.5 Mechanism of chelation therapy
12.6 Side Effects of chlation therapy
13. Complications of lead poisoning
14. Prognosis of lead poisoning
15. Prevention of lead poisoning
15.1 Home renovation
16. Reference
Compiled By
Md. Jakaria
B.Pharm (Hon’s)
10th
Batch, IIUC
1. Introduction
Lead is a naturally occurring bluish-gray metal found in the earth’s crust. Lead can combine
with other chemicals to form what are known as lead salts. These compounds are water-soluble,
while elemental lead is not. Lead is used in the production of batteries, ammunition, metal
products, as well as scientific and medical equipment. Most of the lead mobilized in the
environment is the result of human activities. Exposure to inorganic lead and inorganic lead
compounds or to organic lead compounds can occur in environmental or occupational
circumstances. Inorganic lead exposure is most applicable to general and occupational exposure.
Human body burdens of lead result from inhalation and oral exposure to inorganic lead.
Typically, the lead body burden of an average adult human has been reported to range between
100 and 300 mg. Exposure to lead can affect a number of organs and/or systems in humans and
animals.
2. ADME of Lead
In humans, oral absorption of ingested lead occurs primarily in the gastrointestinal tract; 50
percent of the oral dose is absorbed by children and 15 percent is absorbed by adults.
The main body compartments that store lead are the blood, soft tissues, and bone; Many other
tissues store lead, but those with the highest concentrations (other than blood, bone, and teeth)
are the brain, spleen, kidneys, liver, and lungs. Lead in the bones, teeth, hair, and nails is bound
tightly and not available to other tissues, and is generally thought not to be harmful.
In adults, 94% of absorbed lead is deposited in the bones and teeth, but children only store 70%
in this manner, a fact which may partially account for the more serious health effects on
children.
The half-life of lead in these tissues is measured in weeks for blood, months for soft tissues, and
years for bone. The estimated half-life of lead in bone is 20 to 30 years, and bone can introduce
lead into the bloodstream long after the initial exposure is gone.
The half-life of lead in the blood in men is about 40 days, but it may be longer in children and
pregnant women, whose bones are undergoing remodeling, which allows the lead to be
continuously re-introduced into the bloodstream. Also, if lead exposure takes place over years,
clearance is much slower, partly due to the re-release of lead from bone.
Lead is primarily excreted in urine and bile, but the elimination rate varies, depending on the
tissue that absorbed the lead. The kidney excretes lead from the body very slowly, mainly
through urine by means of glomerular filtration and tubular secretion. Lead has bidirectional
transport across the tubular epithelium. The clearance of lead ranges from 1 to 3 mL/min and is
relatively independent of kidney function. Smaller amounts of lead are also eliminated through
the feces, and very small amounts in hair, nails, and sweat.
3. Definition of Lead Poisoning
Lead is a highly toxic metal and a very strong poison. Lead poisoning (also known as plumbism,
colica pictorum, saturnism, Devon colic, or painter's colic) is a medical condition in humans and
other vertebrates caused by increased levels of the heavy metal lead in the body. Lead poisoning
is a serious and sometimes fatal condition. Lead poisoning occurs when lead builds up in the
body, often over a period of months or years. Even small amounts of lead can cause serious
health problems. Lead poisoning can happen at any age, but it is more harmful to children
younger than 6 years of age and is especially harmful to those younger than 3 years of age; it can
permanently affect a child's physical health and mental development.
4. Main effect of Lead
Lead has no known physiologically relevant role in the body, and its harmful effects are myriad.
 Lead and other heavy metals create reactive radicals which damage cell structures
including DNA and cell membranes.
 Lead also interferes with DNA transcription, enzymes that help in the synthesis of
vitamin D, and enzymes that maintain the integrity of the cell membrane.
 Anemia may result when the cell membranes of red blood cells become more fragile as the
result of damage to their membranes.
 Lead interferes with metabolism of bones and teeth and alters the permeability of blood
vessels and collagen synthesis.
 Lead may also be harmful to the developing immune system, causing production of
excessive inflammatory proteins; this mechanism may mean that lead exposure is a risk
factor for asthma in children.
 Lead exposure has also been associated with a decrease in activity of immune cells such
as polymorphonuclear leukocytes.
 Lead also interferes with the normal metabolism of calcium in cells and causes it to build
up within them.
5. Causes lead poisoning
5.1 Role of Enzymes
The primary cause of lead's toxicity is its interference with a variety of enzymes because it binds
to sulfhydryl groups found on many enzymes. Part of lead's toxicity results from its ability to
mimic other metals that take part in biological processes, which act as cofactors in many
enzymatic reactions, displacing them at the enzymes on which they act. Lead is able to bind to
and interact with many of the same enzymes as these metals but, due to its differing chemistry,
does not properly function as a cofactor, thus interfering with the enzyme's ability to catalyze its
normal reaction or reactions. Among the essential metals with which lead interacts are calcium,
iron, and zinc.
One of the main causes for the pathology of lead is that it interferes with the activity of an
essential enzyme called delta-aminolevulinic acid dehydratase, or ALAD, which is important in
the biosynthesis of heme, the cofactor found in hemoglobin. Lead also inhibits the enzyme
ferrochelatase, another enzyme involved in the formation of heme. Ferrochelatase catalyzes the
joining of protoporphyrin and Fe2+ to form heme. Lead's interference with heme synthesis
results in production of zinc protoporphyrin and the development of anemia. Another effect of
lead's interference with heme synthesis is the buildup of heme precursors, such as
aminolevulinic acid, which may be directly or indirectly harmful to neurons.
5.2 Role of Neurons
Lead exposure damages cells in the hippocampus, a part of the brain involved in memory.
Hippocampi of lead-exposed rats (bottom) show structural damage such as irregular nuclei (IN)
and denaturation of myelin (DNS) compared to controls (top).
Lead interferes with the release of neurotransmitters, chemicals used by neurons to send signals
to other cells. It interferes with the release of glutamate, a neurotransmitter important in many
functions including learning, by blocking NMDA receptors. The targeting of NMDA receptors is
thought to be one of the main causes for lead's toxicity to neurons. A Johns Hopkins University
report found that in addition to inhibiting the NMDA receptor, lead exposure decreased the
amount of the gene for the receptor in part of the brain. In addition, lead has been found in
animal studies to cause programmed cell death in brain cells.
Lead poisoning occurs when lead is ingested. It can also be caused by breathing in dust that
contains lead. You cannot smell or taste lead. It is not visible to the naked eye. Children can be
exposed to lead in many ways. Kids can take in lead by mouth or through breathing lead dust.
They can get dust and paint chips on their hands and then put their hands in their mouths.
Water that comes from pipes with lead soldering can contain lead, too. Some pottery and
ceramic dishes, home remedies, vending machine trinkets, and costume jewelry contain lead.
Even many new, imported toys contain lead paint. There are many common sources of lead
exposure.
5.3 Some potential sources of exposure are:
 Lead paint in houses built before 1978
 This is the primary source of lead dust in pre-1978 homes
 The older the house, the greater the probability it contains lead
 Poster: Where to look for lead in your home
 Especially likely to come from paint around doors and windows
 Imported food cans with lead soldering
 Calcium supplements (from bone meal, dolomite or oyster shells)
 Water from old plumbing fixtures with lead soldering
 Lead in dust and soil. Lead particles that settle on the soil from leaded gasoline or paint
can last for years. Lead-contaminated soil is still a major problem around highways and in
some urban settings.
 Imported colored newspaper and food wrappers (such as for bread and candy)
 Old painted toys and furniture
 New, imported painted toys
 Hobbies that use lead products, such as making stained glass windows
 Exposure at work (parents may bring lead home on their clothes)
 Medicines and home remedies from other countries.
Some cases of lead poisoning have been traced to the use of certain traditional medicines,
including :
Greta or azarcon. This fine orange powder — also known as alarcon, coral, luiga, maria luisa
or rueda — is a Hispanic remedy taken for an upset stomach, constipation, diarrhea and
vomiting. It's also used to soothe teething babies.
Litargirio. Also known as litharge, this peach-colored powder is used as a deodorant,
especially in the Dominican Republic.
Ba-baw-san. This Chinese herbal remedy is used to treat colic pain in babies.
Ghasard. A brown powder, ghasard is used as a tonic in India.
Daw tway. A digestive aid used in Thailand, daw tway contains high levels of lead and
arsenic.
 Food additives
 Toys. Lead is sometimes found in toys and other products produced abroad.
 Some snacks or candies from other countries, such as Chapulines (grasshoppers) from the
Mexican state of Oaxaca or Bolirindo lollipops.
 More on toxic candy and wrappers tested in California.
 Foods made or stored in lead-glazed pottery or lead crystal.
 Ammunition
 Lead sinkers for fishing
 Traditional cosmetics. Kohl is a traditional cosmetic, often used as eyeliner. Testing of
various samples of kohl has revealed high levels of lead.
6. Sign & Symptoms of lead poisoning
Initially, lead poisoning can be hard to detect — even people who seem healthy can have high
blood levels of lead. Signs and symptoms usually don't appear until dangerous amounts have
accumulated.
6.1 Acute poisoning
 In acute poisoning, typical neurological signs are pain, muscle weakness, paraesthesia,
and, rarely, symptoms associated with encephalitis.
 Abdominal pain, nausea, vomiting, diarrhea, and constipation are other acute symptoms.
 Lead's effects on the mouth include astringency and a metallic taste.
 Gastrointestinal problems, such as constipation, diarrhea, poor appetite, or weight loss,
are common in acute poisoning.
 Absorption of large amounts of lead over a short time can cause shock (insufficient fluid in
the circulatory system) due to loss of water from the gastrointestinal tract. Hemolysis (the
rupture of red blood cells) due to acute poisoning can cause anemia and hemoglobin in the
urine.
 Damage to kidneys can cause changes in urination such as decreased urine output. People
who survive acute poisoning often go on to display symptoms of chronic poisoning.
6.2 Chronic poisoning
 Chronic poisoning usually presents with symptoms affecting multiple systems, but is
associated with three main types of symptoms: gastrointestinal, neuromuscular, and
neurological.
 Central nervous system and neuromuscular symptoms usually result from intense
exposure, while gastrointestinal symptoms usually result from exposure over longer
periods.
 Signs of chronic exposure include loss of short-term memory or concentration, depression,
nausea, abdominal pain, loss of coordination, and numbness and tingling in the
extremities. Fatigue, problems with sleep, headaches, stupor, slurred speech, and anemia
are also found in chronic lead poisoning. A "lead hue" of the skin with pallor is another
feature. A blue line along the gum, with bluish black edging to the teeth, known as Burton
line is another indication of chronic lead poisoning. Children with chronic poisoning may
refuse to play or may have hyperkinetic or aggressive behavior disorders.
6.3 Symptoms in children
The signs and symptoms of lead poisoning in children may include:
 Irritability
 Loss of appetite
 Weight loss
 Sluggishness and fatigue
 Abdominal pain
 Vomiting
 Constipation
 Learning difficulties
6.4 Symptoms in newborns
Babies who are exposed to lead before birth may experience:
 Learning difficulties
 Slowed growth
6.5 Symptoms in adults
Although children are primarily at risk, lead poisoning is also dangerous for adults. Signs and
symptoms in adults may include:
 High blood pressure
 Declines in mental functioning
 Pain, numbness or tingling of the extremities
 Muscular weakness
 Headache
 Abdominal pain
 Memory loss
 Mood disorders
 Reduced sperm count, abnormal sperm
 Miscarriage or premature birth in pregnant women
7. Lead Encephalopathy
Lead encephalopathy is a condition in which the brain swells from exposure to extremely high
levels of lead. The swelling increases pressure within the skull (cerebral edema), which can
cause seizures, intellectual disability, paralysis, blindness, coma, and death.
8. Risk factors of lead poisoning
8.1 Factors that may increase your risk of lead poisoning include:
 Age. Infants and young children are more likely to be exposed to lead than are older
children. They may chew paint chips, and their hands may be contaminated with lead
dust. Young children also absorb lead more easily and sustain more harm from it than do
adults and older children. Are 6 years old or younger. Young children are at higher risk
because:
o They often put their hands and objects in their mouths.
o They sometimes swallow nonfood items.
o Their bodies absorb lead at a higher rate.
o Their brains are developing quickly.
 Living in an older home. Although the use of lead-based paints has been banned since the
1970s, older homes and buildings often retain remnants of this paint. People renovating
an older home are at even higher risk.
 Certain hobbies. Work with lead either in their job or as a hobby (for example, metal
smelters, pottery makers, and stained glass artists). Making stained glass requires the
use of lead solder. Refinishing old furniture may put you in contact with layers of lead
paint.
 Country of origin. People who live in developing countries are at higher risk of lead
poisoning because those countries usually have less strict rules regarding exposure to
lead. American families who adopt a child from another country may want to have the
child's blood tested for lead poisoning.
8.2 Others at risk for lead poisoning include people who:
 Drink water that flows through pipes that were soldered with lead.
 Eat food from cans made with lead solder. These types of cans aren't made in the United
States.
 Cook or store food in ceramic containers. Some ceramic glaze contains lead that may not
have been properly fired or cured.
 Eat or breathe traditional or folk remedies that contain lead, such as some herbs and
vitamins from other countries.
 Live in communities with a lot of industrial pollution.
Because lead can harm an unborn child, pregnant women or women likely to become pregnant
should be especially careful to avoid exposure to lead.
9. Differential diagnosis of lead poisoning
This depends on the presentation. Diagnosis may be difficult in the UK where lead poisoning is a
relative rarity but the condition should be on the list in patients presenting with diffuse
abdominal pain.
Other conditions which may need to be considered include:
 Acute confusional states.
 Acute memory loss.
 Epilepsy.
 Encephalopathies.
 Frontal lobe syndromes.
 Depression.
 Attention deficit hyperactivity disorder.
 Learning disorder.
 Developmental delay.
 Language disorder.
 Autism or pervasive developmental disorder.
 Organic solvent poisoning.
 Other heavy metal poisoning.
 Radial mononeuropathy and other peripheral neuropathies.
 Diabetic neuropathy.
 Anaemias, acute and chronic.
 Constipation.
 Guillain-Barré syndrome.
10. Investigations of lead poisoning
10.1 Laboratory tests
Lead poisoning is diagnosed with a blood lead test. This test is performed on a standard blood
sample.
Lead is common in the environment. Low levels in adults are not harmful. However, low levels
in children are a cause for concern. Normal lead levels vary by age group. The amount of lead in
the blood is measured in micrograms per deciliter (mcg/dL).
 Whole blood lead levels:
o <10 μg/dL - normal.
o >10 μg/dL - may cause impaired cognitive development in children.
o >45 μg/dL - GI symptoms in adults and children.
o >70 μg/dL - high risk of acute CNS symptoms.
o >100 μg/dL - may be life-threatening.
 It has been considered for many years that levels of 10 μg/dL have the potential to affect
physical and mental development in children. Studies suggest that levels even lower than
this can be unsafe.
 FBC - basophilic stippling of erythrocytes may be seen and features of a microcytic
hypochromic anaemia such as a low MCV may be present. Sideroblasts may be seen.
 Renal function tests to detect renal complications and uric acid levels to detect gout may
also be advisable.
 Nerve conduction tests should be considered if neuropathy is suspected.
 Psychometric testing should be considered if clinically indicated.
10.2 Radio-imaging
 Plain X-ray may show transverse lines in tubular bones. These are actually areas of
arrested bone growth and may persist a long time after exposure ends. They are not seen
in the early phase of exposure.
 Plain abdominal X-rays may show radio-opaque flecks in cases of suspected lead foreign
body ingestion (e.g., pica in children).
 X-ray fluorescence works by detecting specific emissions from tissues when bombarded
with X-rays. It is a sensitive method of detecting low levels of lead in the body.
 CT or MRI scan of the brain may be contributory in patients with symptoms suggestive of
encephalopathy.
Frontal radiograph of both knees of a child with lead poisoning (Plumbism) show dense metaphyseal bands
involving not only distal femurs and proximal tibias but proximal fibulas as well
11. Management
 In the case of foreign body ingestion (e. g., a child who has swallowed a fishing weight too
large to exit the stomach), approximately three days should be allowed to see if the object
will pass through. If not, it will need to be removed by endoscopy, surgical means or whole
bowel irrigation.
 Severe lead poisoning (levels >60 μg/dL) due to acute ingestion may require:
o Airway maintenance.
o Management of coma and seizures.
o Intravenous (IV) drip of normal saline.
o Orogastric or nasogastric catheter and irrigation with polyethylene glycol.
 For mild lead poisoning (<45 μg/dL) it may be sufficient to detect the source of the
exposure, remove the patient from it and monitor the clinical status.
For more-severe cases, your doctor may recommend:
 Chelation therapy. In this treatment, you take a medication that binds with the lead so
that it's excreted in your urine. Doctors treat lead levels greater than 45 mcg/dL of blood
with a chemical called ethylenediaminetetraacetic acid (EDTA). Depending on your lead
level, you may need more than one treatment. In such severe cases, however, it may not
be possible to reverse damage that has already occurred.
 Dimercaptosuccinic acid (DMSA, or succimer) is given by mouth, is an alternative oral
agent. There is some evidence that it can affect growth rate in children. Most other
chelating agents are given by injection.
 Oral chelation therapy is an option sometimes used for mild-to-moderate poisoning.
 Parenteral chelators such as calcium disodium edetate given intramuscularly (IM) or IV.
There is a growing trend to administer it by slow IV drip.The word 'chelator' is derived
from the Greek for claw and chelators work by forming a tight chemical bond with heavy
metals, enabling them to be excreted. Opinions vary as to when chelation therapy should
be used but it is often employed at levels of 45-60 μg/dL.
 Chelating Agents for Lead Poisoning.
 Examples
Generic Name Brand Name
calcium disodium versenate calcium EDTA, CaNa2EDTA
dimercaprol British anti-lewisite (BAL) in oil
succimer Chemet
 Penicillamine is a chelation agent that is not used very much, it is an unlicensed
medication with adverse effects such as white cell and platelet count suppression. It may
help treat children who have low blood lead levels.
 Chelation therapy should be withdrawn gradually to avoid the metal leaking out of the
bones and causing a rebound rise in blood levels.
 For children and adults with relatively low lead levels, simply avoiding exposure to lead
may be enough to reduce blood lead levels.
12. Short note on chelation therapy
12.1 Chelation therapy:
Chelation therapy is a chemical process in which a synthetic solution—EDTA
(ethylenediaminetetraacetic acid)—is injected into the bloodstream to remove heavy metals
and/or minerals from the body. Chelation means "to grab" or "to bind." When EDTA is injected
into the veins, it "grabs" heavy metals and minerals such as lead, mercury, copper, iron, arsenic,
aluminum, and calcium and removes them from the body. Except as a treatment for lead
poisoning, chelation therapy is controversial and unproved. Chelation therapy is performed on
an outpatient basis.
12.2 Chelation therapy used for:
Chelation is a very effective way to treat heavy-metal poisoning. The U.S. Food and Drug
Administration (FDA) has approved prescription chelation therapy for the treatment of lead
poisoning. Injected EDTA binds with the harmful metal and both are then eliminated from the
body through the kidneys.
Some health professionals have also used chelation therapy to treat atherosclerosis and/or
coronary artery disease, although there is not enough scientific evidence to prove that this
treatment is effective. Some people believe that EDTA binds with calcium deposits (the part of
plaque that obstructs the flow of blood to the heart) in the arteries, and then EDTA "cleans out"
the calcium deposits from the arteries, reducing the risk of heart problems. Research results
have been inconsistent.
Some health professionals also suspect that EDTA may act as an antioxidant by removing
metals that combine with LDL cholesterol, which can damage arteries. The theory is that when
you remove metals that flow freely through arteries (such as copper or calcium), you may slow
down diseases such as atherosclerosis. Research has not proved this theory. Some experts
believe that EDTA could remove calcium from healthy bones, muscles, and other tissues, as well
as from diseased arteries.
Many people report less pain from chronic inflammatory diseases such as arthritis, lupus, and
scleroderma after chelation therapy. The theory is that EDTA acts as an antioxidant, which
protects the body from inflammation and protects blood vessels. Again, this idea has not been
proved by scientific research.
12.3 Chelation therapy may be used if:
 Blood lead levels are 45 micrograms per deciliter (mcg/dL) or higher (in some cases, 20
mcg/dL or higher).
 Symptoms of lead poisoning are present.
 Lead encephalopathy is present.
12.4 Justification of safety of chelation therapy:
Children, pregnant women, and people who have heart or kidney failure should not have
chelation therapy at any dose.
Many years ago, chelation therapy was given in high doses and may have been linked to kidney
damage, irregular heartbeats, and other serious consequences. Even when this treatment is
given in low doses, some negative effects may occur, including high blood pressure, headache,
rash, low blood sugar, and/or thrombophlebitis.
EDTA may remove vital minerals from the body along with the toxic metals. Vitamins and
minerals are added to the EDTA solution to help keep them at an optimal level in the body to
maintain health.
Always tell your doctor if you are using an alternative therapy or if you are thinking about
combining an alternative therapy with your conventional medical treatment. It may not be safe
to forgo your conventional medical treatment and rely only on an alternative therapy.
12.5 Mechanism of chelation therapy
These medicines:
 Bind lead in body tissues and increase elimination of lead in the urine.
 Reduce blood lead levels.
 Reduce further harm from lead poisoning.
12.6 Side Effects
All medicines have side effects. But many people don't feel the side effects, or they are able to
deal with them. Ask your pharmacist about the side effects of each medicine you take. Side
effects are also listed in the information that comes with your medicine.
Here are some important things to think about:
 Usually the benefits of the medicine are more important than any minor side effects.
 Side effects may go away after you take the medicine for a while.
 If side effects still bother you and you wonder if you should keep taking the medicine, call
your doctor. He or she may be able to lower your dose or change your medicine. Do not
suddenly quit taking your medicine unless your doctor tells you to.
13. Complications of lead poisoning
Exposure to even low levels of lead can cause damage over time, especially in children. The greatest risk
is to brain development, where irreversible damage may occur.
 Lead poisoning, with or without encephalopathy, can affect all the systems of the body.
 Higher levels can hepatic, renal and neurological damage in both children and adults .
 Chelation itself can cause problems and treated patients can develop hypertension, raised
intracranial pressure and renal failure from the chelated lead compound.
 Very high lead levels may cause seizures, unconsciousness and possibly death.
14. Prognosis of lead poisoning
 The prognosis has improved considerably with aggressive treatment and there have been
no reported deaths from lead encephalopathy in children in recent years.
 Cases of acute lead encephalopathy in children still occur and can result in severe
neurological damage, seizure disorders, depressed school function and learning
disabilities.
 Adults tend to fare better but long-term effects can include distal motor neuropathies,
depressive disorders, aggressive behaviour, defects in sexual performance and fertility
problems.
15. Prevention of lead poisoning
You can take some simple measures to help protect you and your family from lead poisoning.
These may include:
 Wash hands. To help reduce hand-to-mouth transfer of contaminated dust or soil, wash
your children's hands after outdoor play, before eating and at bedtime.
 Clean dusty surfaces. Clean your floors with a wet mop and wipe furniture, windowsills
and other dusty surfaces with a damp cloth.
 Run cold water. If you have older plumbing containing lead pipes or fittings, run your cold
water for at least a minute before using. Don't use hot tap water to make baby formula or
for cooking.
15.1 Home renovation
If you're doing minor remodeling or touch-up work in an older house with lead-based paint, take
precautions:
 Don't attempt to remove the lead paint by sanding. Sanding surfaces painted with lead is
hazardous because it generates large amounts of small particles.
 Don't use an open-flame torch to remove paint. The flame produces lead particles small
enough to inhale.
 Cover old paint. Removing old lead paint may not always be possible. If the paint is on
tight, without many chips, you can paint over it. You can also use paneling, drywall or
encapsulation, which is similar to a very thick coat of paint.
 Wear protective equipment and clothing. Change your clothes, take a shower and wash
your hair before leaving the job. Don't shake out work clothes or wash them with other
clothes.
 Be careful where you eat. Don't eat or drink in an area where lead dust may be present.
16.1 Reference
 A TEXTBOOK OF MODERN TOXICOLOGY, 3rd Edition by Ernest Hodgson
 PRINCIPLES OF TOXICOLOGY, 2nd EDITION by Phillip L. Williams, Ph.D.
 Lippincott’s Illustrated review of Pharmacology
 http://www.healthline.com/health/lead-poisoning
 http://www.mayoclinic.org/diseases-conditions/lead-poisoning
 http://www.cdc.gov/nceh/lead/
 http://www.med.umich.edu/yourchild/topics/leadpois.htm
 http://www.medicinenet.com/lead_poisoning_symptoms/views.htm
 http://www.nlm.nih.gov/medlineplus/ency/article/002473.htm+
 http://kids.niehs.nih.gov/explore/pollute/lead.htm
 http://www.patient.co.uk/doctor/Lead-Poisoning.htm
 http://en.wikipedia.org/wiki/Lead_poisoning
Compiled By
Md. Jakaria
B. Pharm (Hon’s)
10th
Batch, IIUC
Email: Pharmajakaria@rocketmail.com

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Lead poisoning by jakaria

  • 1. Lead Poisoning Contents 1. Introduction 2. ADME of Lead 3. Definition of Lead Poisoning 4. Main effect of Lead 5. Causes lead poisoning 5.1 Enzymes 5.2 Neurons 5.3 Some potential sources of exposure 5.4 Some cases of lead poisoning have been traced to the use of certain traditional medicines 6. Sign & Symptoms of lead poisoning 6.1 Acute poisoning 6.2 Chronic poisoning 6.3 Symptoms in children 6.4 Symptoms in newborns 6.5 Symptoms in adults 7. Lead Encephalopathy 8. Risk factors of lead poisoning 8.1 Factors that may increase your risk of lead poisoning 8.2 Others risk for lead poisoning 9. Differential diagnosis of lead poisoning 10. Investigations of lead poisoning 10.1 Laboratory tests 10.2 Radio-imaging 11. Management 12. Short note on chelation therapy 12.1 Chelation therapy 12.2 Chelation therapy used for 12.3 Chelation therapy may be used in case of lead poisoning 12.4 Justification of safety of chelation therapy 12.5 Mechanism of chelation therapy 12.6 Side Effects of chlation therapy 13. Complications of lead poisoning 14. Prognosis of lead poisoning 15. Prevention of lead poisoning 15.1 Home renovation 16. Reference Compiled By Md. Jakaria B.Pharm (Hon’s) 10th Batch, IIUC
  • 2. 1. Introduction Lead is a naturally occurring bluish-gray metal found in the earth’s crust. Lead can combine with other chemicals to form what are known as lead salts. These compounds are water-soluble, while elemental lead is not. Lead is used in the production of batteries, ammunition, metal products, as well as scientific and medical equipment. Most of the lead mobilized in the environment is the result of human activities. Exposure to inorganic lead and inorganic lead compounds or to organic lead compounds can occur in environmental or occupational circumstances. Inorganic lead exposure is most applicable to general and occupational exposure. Human body burdens of lead result from inhalation and oral exposure to inorganic lead. Typically, the lead body burden of an average adult human has been reported to range between 100 and 300 mg. Exposure to lead can affect a number of organs and/or systems in humans and animals. 2. ADME of Lead In humans, oral absorption of ingested lead occurs primarily in the gastrointestinal tract; 50 percent of the oral dose is absorbed by children and 15 percent is absorbed by adults. The main body compartments that store lead are the blood, soft tissues, and bone; Many other tissues store lead, but those with the highest concentrations (other than blood, bone, and teeth) are the brain, spleen, kidneys, liver, and lungs. Lead in the bones, teeth, hair, and nails is bound tightly and not available to other tissues, and is generally thought not to be harmful. In adults, 94% of absorbed lead is deposited in the bones and teeth, but children only store 70% in this manner, a fact which may partially account for the more serious health effects on children. The half-life of lead in these tissues is measured in weeks for blood, months for soft tissues, and years for bone. The estimated half-life of lead in bone is 20 to 30 years, and bone can introduce lead into the bloodstream long after the initial exposure is gone. The half-life of lead in the blood in men is about 40 days, but it may be longer in children and pregnant women, whose bones are undergoing remodeling, which allows the lead to be continuously re-introduced into the bloodstream. Also, if lead exposure takes place over years, clearance is much slower, partly due to the re-release of lead from bone. Lead is primarily excreted in urine and bile, but the elimination rate varies, depending on the tissue that absorbed the lead. The kidney excretes lead from the body very slowly, mainly through urine by means of glomerular filtration and tubular secretion. Lead has bidirectional transport across the tubular epithelium. The clearance of lead ranges from 1 to 3 mL/min and is relatively independent of kidney function. Smaller amounts of lead are also eliminated through the feces, and very small amounts in hair, nails, and sweat.
  • 3. 3. Definition of Lead Poisoning Lead is a highly toxic metal and a very strong poison. Lead poisoning (also known as plumbism, colica pictorum, saturnism, Devon colic, or painter's colic) is a medical condition in humans and other vertebrates caused by increased levels of the heavy metal lead in the body. Lead poisoning is a serious and sometimes fatal condition. Lead poisoning occurs when lead builds up in the body, often over a period of months or years. Even small amounts of lead can cause serious health problems. Lead poisoning can happen at any age, but it is more harmful to children younger than 6 years of age and is especially harmful to those younger than 3 years of age; it can permanently affect a child's physical health and mental development. 4. Main effect of Lead Lead has no known physiologically relevant role in the body, and its harmful effects are myriad.  Lead and other heavy metals create reactive radicals which damage cell structures including DNA and cell membranes.  Lead also interferes with DNA transcription, enzymes that help in the synthesis of vitamin D, and enzymes that maintain the integrity of the cell membrane.  Anemia may result when the cell membranes of red blood cells become more fragile as the result of damage to their membranes.  Lead interferes with metabolism of bones and teeth and alters the permeability of blood vessels and collagen synthesis.  Lead may also be harmful to the developing immune system, causing production of excessive inflammatory proteins; this mechanism may mean that lead exposure is a risk factor for asthma in children.  Lead exposure has also been associated with a decrease in activity of immune cells such as polymorphonuclear leukocytes.  Lead also interferes with the normal metabolism of calcium in cells and causes it to build up within them. 5. Causes lead poisoning 5.1 Role of Enzymes The primary cause of lead's toxicity is its interference with a variety of enzymes because it binds to sulfhydryl groups found on many enzymes. Part of lead's toxicity results from its ability to mimic other metals that take part in biological processes, which act as cofactors in many enzymatic reactions, displacing them at the enzymes on which they act. Lead is able to bind to and interact with many of the same enzymes as these metals but, due to its differing chemistry, does not properly function as a cofactor, thus interfering with the enzyme's ability to catalyze its normal reaction or reactions. Among the essential metals with which lead interacts are calcium, iron, and zinc. One of the main causes for the pathology of lead is that it interferes with the activity of an essential enzyme called delta-aminolevulinic acid dehydratase, or ALAD, which is important in the biosynthesis of heme, the cofactor found in hemoglobin. Lead also inhibits the enzyme ferrochelatase, another enzyme involved in the formation of heme. Ferrochelatase catalyzes the joining of protoporphyrin and Fe2+ to form heme. Lead's interference with heme synthesis results in production of zinc protoporphyrin and the development of anemia. Another effect of lead's interference with heme synthesis is the buildup of heme precursors, such as aminolevulinic acid, which may be directly or indirectly harmful to neurons.
  • 4. 5.2 Role of Neurons Lead exposure damages cells in the hippocampus, a part of the brain involved in memory. Hippocampi of lead-exposed rats (bottom) show structural damage such as irregular nuclei (IN) and denaturation of myelin (DNS) compared to controls (top). Lead interferes with the release of neurotransmitters, chemicals used by neurons to send signals to other cells. It interferes with the release of glutamate, a neurotransmitter important in many functions including learning, by blocking NMDA receptors. The targeting of NMDA receptors is thought to be one of the main causes for lead's toxicity to neurons. A Johns Hopkins University report found that in addition to inhibiting the NMDA receptor, lead exposure decreased the amount of the gene for the receptor in part of the brain. In addition, lead has been found in animal studies to cause programmed cell death in brain cells. Lead poisoning occurs when lead is ingested. It can also be caused by breathing in dust that contains lead. You cannot smell or taste lead. It is not visible to the naked eye. Children can be exposed to lead in many ways. Kids can take in lead by mouth or through breathing lead dust. They can get dust and paint chips on their hands and then put their hands in their mouths. Water that comes from pipes with lead soldering can contain lead, too. Some pottery and ceramic dishes, home remedies, vending machine trinkets, and costume jewelry contain lead. Even many new, imported toys contain lead paint. There are many common sources of lead exposure. 5.3 Some potential sources of exposure are:  Lead paint in houses built before 1978  This is the primary source of lead dust in pre-1978 homes  The older the house, the greater the probability it contains lead  Poster: Where to look for lead in your home  Especially likely to come from paint around doors and windows  Imported food cans with lead soldering  Calcium supplements (from bone meal, dolomite or oyster shells)  Water from old plumbing fixtures with lead soldering  Lead in dust and soil. Lead particles that settle on the soil from leaded gasoline or paint can last for years. Lead-contaminated soil is still a major problem around highways and in some urban settings.  Imported colored newspaper and food wrappers (such as for bread and candy)  Old painted toys and furniture  New, imported painted toys  Hobbies that use lead products, such as making stained glass windows  Exposure at work (parents may bring lead home on their clothes)  Medicines and home remedies from other countries. Some cases of lead poisoning have been traced to the use of certain traditional medicines, including : Greta or azarcon. This fine orange powder — also known as alarcon, coral, luiga, maria luisa or rueda — is a Hispanic remedy taken for an upset stomach, constipation, diarrhea and vomiting. It's also used to soothe teething babies.
  • 5. Litargirio. Also known as litharge, this peach-colored powder is used as a deodorant, especially in the Dominican Republic. Ba-baw-san. This Chinese herbal remedy is used to treat colic pain in babies. Ghasard. A brown powder, ghasard is used as a tonic in India. Daw tway. A digestive aid used in Thailand, daw tway contains high levels of lead and arsenic.  Food additives  Toys. Lead is sometimes found in toys and other products produced abroad.  Some snacks or candies from other countries, such as Chapulines (grasshoppers) from the Mexican state of Oaxaca or Bolirindo lollipops.  More on toxic candy and wrappers tested in California.  Foods made or stored in lead-glazed pottery or lead crystal.  Ammunition  Lead sinkers for fishing  Traditional cosmetics. Kohl is a traditional cosmetic, often used as eyeliner. Testing of various samples of kohl has revealed high levels of lead. 6. Sign & Symptoms of lead poisoning Initially, lead poisoning can be hard to detect — even people who seem healthy can have high blood levels of lead. Signs and symptoms usually don't appear until dangerous amounts have accumulated. 6.1 Acute poisoning  In acute poisoning, typical neurological signs are pain, muscle weakness, paraesthesia, and, rarely, symptoms associated with encephalitis.  Abdominal pain, nausea, vomiting, diarrhea, and constipation are other acute symptoms.  Lead's effects on the mouth include astringency and a metallic taste.  Gastrointestinal problems, such as constipation, diarrhea, poor appetite, or weight loss, are common in acute poisoning.  Absorption of large amounts of lead over a short time can cause shock (insufficient fluid in the circulatory system) due to loss of water from the gastrointestinal tract. Hemolysis (the rupture of red blood cells) due to acute poisoning can cause anemia and hemoglobin in the urine.  Damage to kidneys can cause changes in urination such as decreased urine output. People who survive acute poisoning often go on to display symptoms of chronic poisoning. 6.2 Chronic poisoning  Chronic poisoning usually presents with symptoms affecting multiple systems, but is associated with three main types of symptoms: gastrointestinal, neuromuscular, and neurological.  Central nervous system and neuromuscular symptoms usually result from intense exposure, while gastrointestinal symptoms usually result from exposure over longer periods.  Signs of chronic exposure include loss of short-term memory or concentration, depression, nausea, abdominal pain, loss of coordination, and numbness and tingling in the
  • 6. extremities. Fatigue, problems with sleep, headaches, stupor, slurred speech, and anemia are also found in chronic lead poisoning. A "lead hue" of the skin with pallor is another feature. A blue line along the gum, with bluish black edging to the teeth, known as Burton line is another indication of chronic lead poisoning. Children with chronic poisoning may refuse to play or may have hyperkinetic or aggressive behavior disorders. 6.3 Symptoms in children The signs and symptoms of lead poisoning in children may include:  Irritability  Loss of appetite  Weight loss  Sluggishness and fatigue  Abdominal pain  Vomiting  Constipation  Learning difficulties 6.4 Symptoms in newborns Babies who are exposed to lead before birth may experience:  Learning difficulties  Slowed growth 6.5 Symptoms in adults Although children are primarily at risk, lead poisoning is also dangerous for adults. Signs and symptoms in adults may include:  High blood pressure  Declines in mental functioning  Pain, numbness or tingling of the extremities  Muscular weakness  Headache  Abdominal pain  Memory loss  Mood disorders  Reduced sperm count, abnormal sperm  Miscarriage or premature birth in pregnant women 7. Lead Encephalopathy Lead encephalopathy is a condition in which the brain swells from exposure to extremely high levels of lead. The swelling increases pressure within the skull (cerebral edema), which can cause seizures, intellectual disability, paralysis, blindness, coma, and death.
  • 7. 8. Risk factors of lead poisoning 8.1 Factors that may increase your risk of lead poisoning include:  Age. Infants and young children are more likely to be exposed to lead than are older children. They may chew paint chips, and their hands may be contaminated with lead dust. Young children also absorb lead more easily and sustain more harm from it than do adults and older children. Are 6 years old or younger. Young children are at higher risk because: o They often put their hands and objects in their mouths. o They sometimes swallow nonfood items. o Their bodies absorb lead at a higher rate. o Their brains are developing quickly.  Living in an older home. Although the use of lead-based paints has been banned since the 1970s, older homes and buildings often retain remnants of this paint. People renovating an older home are at even higher risk.  Certain hobbies. Work with lead either in their job or as a hobby (for example, metal smelters, pottery makers, and stained glass artists). Making stained glass requires the use of lead solder. Refinishing old furniture may put you in contact with layers of lead paint.  Country of origin. People who live in developing countries are at higher risk of lead poisoning because those countries usually have less strict rules regarding exposure to lead. American families who adopt a child from another country may want to have the child's blood tested for lead poisoning. 8.2 Others at risk for lead poisoning include people who:  Drink water that flows through pipes that were soldered with lead.  Eat food from cans made with lead solder. These types of cans aren't made in the United States.  Cook or store food in ceramic containers. Some ceramic glaze contains lead that may not have been properly fired or cured.  Eat or breathe traditional or folk remedies that contain lead, such as some herbs and vitamins from other countries.  Live in communities with a lot of industrial pollution. Because lead can harm an unborn child, pregnant women or women likely to become pregnant should be especially careful to avoid exposure to lead. 9. Differential diagnosis of lead poisoning This depends on the presentation. Diagnosis may be difficult in the UK where lead poisoning is a relative rarity but the condition should be on the list in patients presenting with diffuse abdominal pain. Other conditions which may need to be considered include:  Acute confusional states.  Acute memory loss.  Epilepsy.  Encephalopathies.  Frontal lobe syndromes.
  • 8.  Depression.  Attention deficit hyperactivity disorder.  Learning disorder.  Developmental delay.  Language disorder.  Autism or pervasive developmental disorder.  Organic solvent poisoning.  Other heavy metal poisoning.  Radial mononeuropathy and other peripheral neuropathies.  Diabetic neuropathy.  Anaemias, acute and chronic.  Constipation.  Guillain-Barré syndrome. 10. Investigations of lead poisoning 10.1 Laboratory tests Lead poisoning is diagnosed with a blood lead test. This test is performed on a standard blood sample. Lead is common in the environment. Low levels in adults are not harmful. However, low levels in children are a cause for concern. Normal lead levels vary by age group. The amount of lead in the blood is measured in micrograms per deciliter (mcg/dL).  Whole blood lead levels: o <10 μg/dL - normal. o >10 μg/dL - may cause impaired cognitive development in children. o >45 μg/dL - GI symptoms in adults and children. o >70 μg/dL - high risk of acute CNS symptoms. o >100 μg/dL - may be life-threatening.  It has been considered for many years that levels of 10 μg/dL have the potential to affect physical and mental development in children. Studies suggest that levels even lower than this can be unsafe.  FBC - basophilic stippling of erythrocytes may be seen and features of a microcytic hypochromic anaemia such as a low MCV may be present. Sideroblasts may be seen.  Renal function tests to detect renal complications and uric acid levels to detect gout may also be advisable.  Nerve conduction tests should be considered if neuropathy is suspected.  Psychometric testing should be considered if clinically indicated. 10.2 Radio-imaging  Plain X-ray may show transverse lines in tubular bones. These are actually areas of arrested bone growth and may persist a long time after exposure ends. They are not seen in the early phase of exposure.  Plain abdominal X-rays may show radio-opaque flecks in cases of suspected lead foreign body ingestion (e.g., pica in children).  X-ray fluorescence works by detecting specific emissions from tissues when bombarded with X-rays. It is a sensitive method of detecting low levels of lead in the body.  CT or MRI scan of the brain may be contributory in patients with symptoms suggestive of encephalopathy.
  • 9. Frontal radiograph of both knees of a child with lead poisoning (Plumbism) show dense metaphyseal bands involving not only distal femurs and proximal tibias but proximal fibulas as well 11. Management  In the case of foreign body ingestion (e. g., a child who has swallowed a fishing weight too large to exit the stomach), approximately three days should be allowed to see if the object will pass through. If not, it will need to be removed by endoscopy, surgical means or whole bowel irrigation.  Severe lead poisoning (levels >60 μg/dL) due to acute ingestion may require: o Airway maintenance. o Management of coma and seizures. o Intravenous (IV) drip of normal saline. o Orogastric or nasogastric catheter and irrigation with polyethylene glycol.  For mild lead poisoning (<45 μg/dL) it may be sufficient to detect the source of the exposure, remove the patient from it and monitor the clinical status. For more-severe cases, your doctor may recommend:  Chelation therapy. In this treatment, you take a medication that binds with the lead so that it's excreted in your urine. Doctors treat lead levels greater than 45 mcg/dL of blood with a chemical called ethylenediaminetetraacetic acid (EDTA). Depending on your lead level, you may need more than one treatment. In such severe cases, however, it may not be possible to reverse damage that has already occurred.  Dimercaptosuccinic acid (DMSA, or succimer) is given by mouth, is an alternative oral agent. There is some evidence that it can affect growth rate in children. Most other chelating agents are given by injection.  Oral chelation therapy is an option sometimes used for mild-to-moderate poisoning.  Parenteral chelators such as calcium disodium edetate given intramuscularly (IM) or IV. There is a growing trend to administer it by slow IV drip.The word 'chelator' is derived from the Greek for claw and chelators work by forming a tight chemical bond with heavy metals, enabling them to be excreted. Opinions vary as to when chelation therapy should be used but it is often employed at levels of 45-60 μg/dL.  Chelating Agents for Lead Poisoning.
  • 10.  Examples Generic Name Brand Name calcium disodium versenate calcium EDTA, CaNa2EDTA dimercaprol British anti-lewisite (BAL) in oil succimer Chemet  Penicillamine is a chelation agent that is not used very much, it is an unlicensed medication with adverse effects such as white cell and platelet count suppression. It may help treat children who have low blood lead levels.  Chelation therapy should be withdrawn gradually to avoid the metal leaking out of the bones and causing a rebound rise in blood levels.  For children and adults with relatively low lead levels, simply avoiding exposure to lead may be enough to reduce blood lead levels. 12. Short note on chelation therapy 12.1 Chelation therapy: Chelation therapy is a chemical process in which a synthetic solution—EDTA (ethylenediaminetetraacetic acid)—is injected into the bloodstream to remove heavy metals and/or minerals from the body. Chelation means "to grab" or "to bind." When EDTA is injected into the veins, it "grabs" heavy metals and minerals such as lead, mercury, copper, iron, arsenic, aluminum, and calcium and removes them from the body. Except as a treatment for lead poisoning, chelation therapy is controversial and unproved. Chelation therapy is performed on an outpatient basis. 12.2 Chelation therapy used for: Chelation is a very effective way to treat heavy-metal poisoning. The U.S. Food and Drug Administration (FDA) has approved prescription chelation therapy for the treatment of lead poisoning. Injected EDTA binds with the harmful metal and both are then eliminated from the body through the kidneys. Some health professionals have also used chelation therapy to treat atherosclerosis and/or coronary artery disease, although there is not enough scientific evidence to prove that this treatment is effective. Some people believe that EDTA binds with calcium deposits (the part of plaque that obstructs the flow of blood to the heart) in the arteries, and then EDTA "cleans out" the calcium deposits from the arteries, reducing the risk of heart problems. Research results have been inconsistent. Some health professionals also suspect that EDTA may act as an antioxidant by removing metals that combine with LDL cholesterol, which can damage arteries. The theory is that when you remove metals that flow freely through arteries (such as copper or calcium), you may slow down diseases such as atherosclerosis. Research has not proved this theory. Some experts believe that EDTA could remove calcium from healthy bones, muscles, and other tissues, as well as from diseased arteries.
  • 11. Many people report less pain from chronic inflammatory diseases such as arthritis, lupus, and scleroderma after chelation therapy. The theory is that EDTA acts as an antioxidant, which protects the body from inflammation and protects blood vessels. Again, this idea has not been proved by scientific research. 12.3 Chelation therapy may be used if:  Blood lead levels are 45 micrograms per deciliter (mcg/dL) or higher (in some cases, 20 mcg/dL or higher).  Symptoms of lead poisoning are present.  Lead encephalopathy is present. 12.4 Justification of safety of chelation therapy: Children, pregnant women, and people who have heart or kidney failure should not have chelation therapy at any dose. Many years ago, chelation therapy was given in high doses and may have been linked to kidney damage, irregular heartbeats, and other serious consequences. Even when this treatment is given in low doses, some negative effects may occur, including high blood pressure, headache, rash, low blood sugar, and/or thrombophlebitis. EDTA may remove vital minerals from the body along with the toxic metals. Vitamins and minerals are added to the EDTA solution to help keep them at an optimal level in the body to maintain health. Always tell your doctor if you are using an alternative therapy or if you are thinking about combining an alternative therapy with your conventional medical treatment. It may not be safe to forgo your conventional medical treatment and rely only on an alternative therapy. 12.5 Mechanism of chelation therapy These medicines:  Bind lead in body tissues and increase elimination of lead in the urine.  Reduce blood lead levels.  Reduce further harm from lead poisoning. 12.6 Side Effects All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine. Here are some important things to think about:  Usually the benefits of the medicine are more important than any minor side effects.  Side effects may go away after you take the medicine for a while.  If side effects still bother you and you wonder if you should keep taking the medicine, call your doctor. He or she may be able to lower your dose or change your medicine. Do not suddenly quit taking your medicine unless your doctor tells you to.
  • 12. 13. Complications of lead poisoning Exposure to even low levels of lead can cause damage over time, especially in children. The greatest risk is to brain development, where irreversible damage may occur.  Lead poisoning, with or without encephalopathy, can affect all the systems of the body.  Higher levels can hepatic, renal and neurological damage in both children and adults .  Chelation itself can cause problems and treated patients can develop hypertension, raised intracranial pressure and renal failure from the chelated lead compound.  Very high lead levels may cause seizures, unconsciousness and possibly death. 14. Prognosis of lead poisoning  The prognosis has improved considerably with aggressive treatment and there have been no reported deaths from lead encephalopathy in children in recent years.  Cases of acute lead encephalopathy in children still occur and can result in severe neurological damage, seizure disorders, depressed school function and learning disabilities.  Adults tend to fare better but long-term effects can include distal motor neuropathies, depressive disorders, aggressive behaviour, defects in sexual performance and fertility problems. 15. Prevention of lead poisoning You can take some simple measures to help protect you and your family from lead poisoning. These may include:  Wash hands. To help reduce hand-to-mouth transfer of contaminated dust or soil, wash your children's hands after outdoor play, before eating and at bedtime.  Clean dusty surfaces. Clean your floors with a wet mop and wipe furniture, windowsills and other dusty surfaces with a damp cloth.  Run cold water. If you have older plumbing containing lead pipes or fittings, run your cold water for at least a minute before using. Don't use hot tap water to make baby formula or for cooking. 15.1 Home renovation If you're doing minor remodeling or touch-up work in an older house with lead-based paint, take precautions:  Don't attempt to remove the lead paint by sanding. Sanding surfaces painted with lead is hazardous because it generates large amounts of small particles.  Don't use an open-flame torch to remove paint. The flame produces lead particles small enough to inhale.  Cover old paint. Removing old lead paint may not always be possible. If the paint is on tight, without many chips, you can paint over it. You can also use paneling, drywall or encapsulation, which is similar to a very thick coat of paint.  Wear protective equipment and clothing. Change your clothes, take a shower and wash your hair before leaving the job. Don't shake out work clothes or wash them with other clothes.  Be careful where you eat. Don't eat or drink in an area where lead dust may be present.
  • 13. 16.1 Reference  A TEXTBOOK OF MODERN TOXICOLOGY, 3rd Edition by Ernest Hodgson  PRINCIPLES OF TOXICOLOGY, 2nd EDITION by Phillip L. Williams, Ph.D.  Lippincott’s Illustrated review of Pharmacology  http://www.healthline.com/health/lead-poisoning  http://www.mayoclinic.org/diseases-conditions/lead-poisoning  http://www.cdc.gov/nceh/lead/  http://www.med.umich.edu/yourchild/topics/leadpois.htm  http://www.medicinenet.com/lead_poisoning_symptoms/views.htm  http://www.nlm.nih.gov/medlineplus/ency/article/002473.htm+  http://kids.niehs.nih.gov/explore/pollute/lead.htm  http://www.patient.co.uk/doctor/Lead-Poisoning.htm  http://en.wikipedia.org/wiki/Lead_poisoning Compiled By Md. Jakaria B. Pharm (Hon’s) 10th Batch, IIUC Email: Pharmajakaria@rocketmail.com