Lead poisoning (saturnism) occurs when the toxic metal lead is ingested. The human organism is damaged by the heavy metal lead.
What is lead poisoning?
A distinction is made between acute and chronic lead poisoning. Acute lead poisoning occurs only when very large amounts of lead or lead compounds are ingested once. In adults, for example, a dose of 5 to 30 grams of the lead salt lead acetate, which is readily soluble in water, has a lethal effect. In contrast, a daily intake of 1 microgram, e.g., via food, only leads to chronic lead poisoning after a longer period of time. The World Health Organization estimates that a daily lead intake by mouth averages about 100 to 500 milligrams. Various organs of the human body are affected by lead poisoning. These include both the peripheral and central nervous systems, the bone marrow, which is also largely responsible for blood formation, the gastrointestinal tract, the gonads, the skin and the kidneys.
Causes
Today, lead poisoning is primarily a result of workplace accidents or the consumption of contaminated drugs, whereas in the past, lead poisoning was also common due to lead-containing objects such as water pipes, cans, or dishes. Lead poisoning occurs in particular when lead-containing vapors or dusts are inhaled, e.g., during the processing of lead-based paints. But lead can also enter the body through skin contact or food. For example, lead-containing ointments used in beauty care can cause lead poisoning. Chronic lead poisoning in adults occurs when an amount of lead of about 500 nanograms or more is ingested. 95% of the lead that enters the blood binds to the erythrocytes (red blood cells) and to blood proteins. Lead then travels through the bloodstream to organs such as the brain, liver and lungs, where it has a 20-day half-life. While some lead is excreted, some is also deposited in teeth and bones. There, the half-life is 5 to 20 years. If bone substance is degraded to a greater extent, the level of lead in the blood may increase even without new lead being supplied from outside the body. Because lead also crosses the placenta, lead poisoning can be passed from mother to unborn child.
Symptoms, complaints, and signs
Chronic or acute poisoning occurs, depending on the severity and duration of lead exposure. Acute lead poisoning is characterized by headaches, aching limbs, severe abdominal cramps, and lassitude. In severe cases, coma and circulatory failure with death may occur. Spastic ileus (intestinal obstruction) is also possible. Acute lead poisoning can be treated with gastric lavage. However, chronic lead poisoning is more insidious. Long-term contamination with lead can lead to various symptoms. Since the heavy metal has an inhibitory effect on blood formation, so-called lead anemia develops in chronic lead poisoning. Like all forms of anemia, this leads to fatigue and reduced physical and mental performance. A bluish-gray to black-gray coating of lead sulfide is deposited on the gums. The cardiovascular system is impaired due to the vasodilator hormones released by lead. Cardiac arrhythmias, cardiac insufficiency and myocardial infarction may occur. Furthermore, due to damage to the nervous system and brain, such symptoms as disorientation, headaches, aggressiveness, hyperactivity, insomnia or apathy occur. Severe cases of nerve damage are characterized by delirium, coma or convulsions, which can lead to death from circulatory failure. Furthermore, numbness and sensory disturbances in the extremities as well as motor deficits are possible. Finally, kidney damage can also develop in the long term above a certain lead concentration in the blood.
Diagnosis and course
Symptoms of acute lead poisoning, which is rather rare, include insomnia, dizziness, headache, abdominal pain, and seizures despite severe fatigue, a slowing of movements, and states resembling delirium. Brain damage (lead encephalopathy) occurs, especially in children who suffer lead poisoning. Acute lead poisoning is a severe poisoning that can lead to coma and death due to circulatory failure.In chronic lead poisoning, loss of appetite, fatigue, headache, abdominal pain and constipation are noted. The patient’s skin appears grayish-yellow, while the edge of the gums is darkened with a so-called lead fringe. Lead impedes the formation of red blood pigment, so that anemia (lead anemia) occurs. It can also cause severe kidney damage. In the case of nerve disease due to lead poisoning (polyneuropathy), paralysis of the extensor muscles in the arms, hearing loss and ringing in the ears regularly occur. Especially in children, lead poisoning can cause brain damage. The diagnosis of lead poisoning is best made by means of a blood test, but can also be made by analyzing urine, hair or teeth. In urine, however, lead may be irregularly distributed due to the body’s not necessarily uniform fluid utilization, so measurement inaccuracies in lead poisoning cannot be ruled out.
Complications
Lead poisoning usually causes fatigue, nausea, and vomiting immediately. In the longer term, improper treatment of the poisoning can cause further complications. In children, even a small amount of lead can cause permanent physical and mental damage. The major complications are developmental disorders, hearing problems, coordination and concentration difficulties. In addition, behavioral problems such as aggressiveness and hyperactivity can occur. Typical physical complications of lead poisoning include kidney damage and lung disease. Rarely, lead poisoning can lead to life-threatening sepsis with serious consequences. Larger amounts of lead also pose a risk of kidney failure, which can also be fatal if left untreated. Chronic lead poisoning reduces general well-being and is associated with loss of appetite, fatigue, headaches, abdominal pain and constipation. In addition, because lead reduces the formation of red blood cells, the risk of anemia increases. Furthermore, permanent kidney damage and other complications may develop. The extent of the symptoms depends largely on the amount of lead ingested and the constitution of the affected person; prompt treatment significantly reduces the risk of permanent damage and usually leads to a full recovery of the patient.
When should you see a doctor?
Acute lead poisoning is a potentially life-threatening disorder that should not be underestimated or downplayed. It is imperative that medical attention be sought if large amounts of the toxic substance are ingested. Thirty grams of lead is considered acutely life-threatening, but for many people even a much smaller amount is lethal. Large amounts of lead are usually only ingested in workplace accidents. Affected persons can recognize lead poisoning by a number of characteristic symptoms. Typical symptoms include loss of the sense of taste and severe abdominal pain that can radiate to the upper regions of the body. Anyone who works in a plant that processes lead or lead-containing materials should seek medical attention immediately if they experience these symptoms. If additional symptoms such as dizziness, seizures, and impaired coordination occur, emergency medical attention must be sought without hesitation. Chronic lead poisoning should also be treated by a doctor. However, they are more difficult for those affected to identify. Chronic lead poisoning should be suspected if a person feels constantly stressed for no apparent reason, complains of diffuse headaches and abdominal pain, and shows signs of anemia. Typical symptoms also include a yellowish discoloration of the skin and the so-called lead fringe, a blue-black discoloration of the gums. Anyone who observes such symptoms should see a doctor immediately.
Treatment and therapy
Treatment of lead poisoning depends on the type of lead ingestion and the duration of poisoning. If the lead is ingested by mouth, an attempt is made to remove as much of the heavy metal from the body as possible by vomiting or by gastric lavage. In acute lead poisoning, the fluid used for gastric lavage consists of a three percent sodium sulfate solution. Activated charcoal is administered at the same time, which causes the lead components – converted into lead sulfate, which is more difficult to dissolve – to bind to the activated charcoal.If the lead has already passed beyond the stomach and entered the body, the patient is administered drugs such as penicillamine, which bind the lead in his body and thus render it harmless, so that the heavy metal can be excreted again via the kidneys. At this point, the blood provides an ideal means of monitoring whether the therapy is working as desired. Antispasmodic preparations (spasmolytics) are used to treat abdominal pain. If kidney damage has occurred, blood washing may be required temporarily or even permanently. It is imperative that the sufferer avoid any further contact with the heavy metal lead. To do so, however, it is necessary to clearly identify the source of lead poisoning.
Outlook and prognosis
The prognosis for lead poisoning depends on the amount of lead in the body and the duration of exposure. The earlier lead poisoning is identified and treated, the better the prognosis. Mild cases of acute lead poisoning have a particularly good prognosis in this regard. Younger children are more severely affected by acute lead poisoning than adults. For example, in addition to colic, brain damage can occur in children, making their prognosis less favorable and requiring even more rapid action. Chronic lead poisoning will lead to death after some time if not treated. Nerve and kidney damage in particular play a role here, as they ultimately render the affected person incapable of living. Nevertheless, even severe cases of chronic lead intoxication can be treated with complexing agents and chelation therapy. However, damage to organs that has already occurred on a structural level cannot be reversed with this, so that affected persons will continue to live with limitations after therapy. Chronic lead intoxication can also recur in the affected person and lead to symptoms if the source of the damage cannot be located.
Prevention
Lead poisoning can be prevented primarily by avoiding the release of lead. The use of many lead-containing materials has been restricted or banned. Waste materials containing lead (e.g., in old car batteries) are disposed of separately. Water pipes still containing lead, which can contaminate drinking water with lead to a considerable extent, should be replaced. Pregnant women and young children in particular must avoid drinking water containing lead.
Follow-up
Follow-up care is especially important in cases of lead poisoning if the poisoning is severe and secondary illnesses have occurred. For example, severe lead poisoning can damage the brain and impair cognitive abilities. In this case, it is important for patients to exercise their cognitive abilities regularly to minimize long-term damage. In particular, a reduction in memory caused by lead poisoning and severe concentration disorders can be alleviated by targeted exercises. Children often show psychological conspicuousness, especially increased aggressiveness or the exact opposite, listlessness and lethargy or frequent crying fits. This behavior can be counteracted by targeted educational measures. Physiotherapeutic support and treatment of damage to muscles and joints is also important. Here, too, regular, targeted exercises can significantly improve the performance of the affected muscles and joints. Pregnant women should be informed about possible fertility damage to the embryo and the increased risk of stillbirth. Patients whose gastrointestinal tract in particular has been damaged may need to be put on a light diet for a longer period of time, possibly including a general change in diet. Lead poisoning can also cause damage to the gums, often with a time lag, which is why appropriate dental care should also be ensured. Because of the increased risk of cancer, patients should also be made aware of the importance of screening.
Here’s what you can do yourself
If lead poisoning is suspected, the first course of action is to see a doctor. Once the poisoning is diagnosed, recovery can be aided by a few home remedies and self-measures. First, drink plenty of fluids regularly to flush out the lead.Sporting activities as well as regular sauna sessions promote the formation of sweat and thus also the flushing out of the harmful substance. Various natural remedies such as Schuessler’s salts or chlorella algae achieve a similar effect. To ensure that detoxification succeeds without complications, the internal organs such as the liver, kidneys, intestines and lungs should also be strengthened. Physical exercise is also recommended here, in addition to a healthy and balanced diet. If the lead poisoning has already caused psychological damage, this must be treated by various therapeutic measures. As complementary self-measures, relaxation exercises, conversations with friends and family members, and sometimes a change of environment are recommended. First, however, the cause of the lead poisoning must be determined and eliminated. This is possible, for example, by moving house (e.g., in the case of lead in wall paint) or changing jobs. Appropriate steps should always be discussed first with the responsible physician.