Introduction
Build-up of heavy metals in the body’s soft tissues in dangerous proportions is known as heavy metal poisoning. Depending on the amount of metal accumulating, different symptoms and physical findings are linked to heavy metal poisoning. In extremely small levels, many heavy metals, including zinc, copper, chromium, iron, and manganese, are necessary for physiological function. However, substantial harm could result if these metals build up in the body to the point where they become poisonous.
Heavy metal toxicity is caused by prolonged or regular exposure to heavy metals. Heavy metal toxicity will not result from infrequent exposure.
The heavy metals lead, mercury, arsenic, and cadmium are most frequently linked to human toxicity. Foods, pharmaceuticals, inadequately protected food containers, exposure to heavy metals at work, contamination of the air or water, and lead-based paint consumption can all result in heavy metal poisoning. Heavy Metal Poisonings are:
- Aluminum Poisoning
- Antimony Poisoning
- Arsenic Poisoning
- Barium Poisoning
- Bismuth Poisoning
- Cadmium Poisoning
- Chromium Poisoning
- Cobalt Poisoning
- Copper Poisoning
- Gold Poisoning
- Iron Poisoning
- Lead Poisoning
- Lithium Poisoning
- Manganese Poisoning
- Mercury Poisoning
- Nickel Poisoning
- Phosphorous Poisoning
- Platinum Poisoning
- Selenium Poisoning
- Silver Poisoning
- Thallium Poisoning
- Tin Poisoning
- Zinc Poisoning
Signs & Symptoms
Depending on the type of metal potential exposure involved, different heavy metal poisoning symptoms may be present. Several such instances include:
Arsenic Poisoning
In order to make pesticides, arsenic is used. There are several industrial uses for arsenic gas as well. Overexposure may result in life-threatening consequences such as seizures, drowsiness, headache, and sleepiness. Damage to the brain (encephalopathy), peripheral neuropathy, pericapillary haemorrhages inside the white matter, and loss or deficiency of the fatty coverings (myelin) around these nerve fibres are examples of neurological symptoms (demyelination). Mees’ lines, which are transverse white bands on the nails, are a sign of skin issues, as is an abnormal buildup of fluid in the soft tissue beneath the skin (edema). Gastroenteritis, a condition with symptoms similar to the flu, causes vomiting, abdominal pain, fever, and diarrhoea, which in some cases may be bloody. Hemolysis, a low level of iron in red blood cells (anaemia), and low blood pressure are additional symptoms. Hemolysis is the breakdown of haemoglobin in red blood cells. Some people could smell like garlic and it might be noticeable on their breath.
Weakness, aches and pains in the muscles, chills, and fever are symptoms of persistent poisoning. About two to eight weeks after exposure, signs of chronic arsenic poisoning start to appear. Skin and nail symptoms include transverse white bands on the fingernails (mees’ lines), hardened patches of skin (hyperkeratosis) with unusually deep creases on the palms of the hands and soles of the feet, unusual darkening of certain areas of the skin (hyperpigmentation), and scale-like skin inflammation (exfoliative dermatitis).
Polyneuritis, an inflammation of the sensory and motor nerves, and sore throat are other symptoms.
The liver, spleen, kidneys, lungs, and digestive system all gather inorganic arsenic. It then leaves a deposit in tissues including skin, hair, and nails after passing through these areas. In addition to heart issues (cardiomyopathy), acid buildup in the kidneys’ tubes (renal tubular acidosis), the breakdown of red blood cells’ haemoglobin (hemolysis), irregular heartbeats (ventricular arrhythmias), coma, seizures, intestinal bleeding (intestinal haemorrhage), and yellowing of the skin, mucous membranes, and whites of the eyes are all symptoms of severe inorganic arsenic poisoning.
Causes
Fowler’s solution (potassium arsenite), as well as other topical lotions intended to treat specific skin diseases, can all result in arsenic poisoning. Arsenic poisoning may result through ingesting herbicides, insecticides, pesticides, fungicides, or rodenticides that contain the metal. Arsenic poisoning may result from occupational exposure to arsenic during the production of paints, enamels, glass, and metals. Galvanizing, soldering, etching, lead plating, smelting, and wood preservation are further occupational exposures. Additionally, contaminated fish, algae, and water contain arsenic.
Diagnosis
Increased amounts of arsenic in the hair, nails, and urine can be used to confirm the diagnosis of arsenic poisoning. An abdominal x-ray may reveal swallowed arsenic, which is not visible on x-rays (radiopaque).
Cadmium Poisoning
Many products, including electroplating, storage batteries, vapour lamps, and some solders, incorporate cadmium. Symptoms may be delayed for 2-4 hours. Fatigue, headache, nausea, vomiting, cramps in the stomach, diarrhoea, and fever can all result from excessive exposure. Additionally, emphysema, an abnormal buildup of fluid in the lungs (pulmonary edoema), and dyspnea, or shortness of breath, may also be present. Some symptoms of the condition include increased salivation, tooth yellowing, tachycardia, low iron levels in red blood cells, cyanosis (bluish colouring) of the skin and mucous membranes as a result of insufficient oxygen delivery to these tissues, and/or a diminished sense of smell (anosmia). In addition to abnormally high levels of protein in the urine (proteinuria), mild alterations in liver function, and/or weakening of some bones (osteomalacia), people with cadmium poisoning may also experience aberrant kidney function (renal tubular dysfunction).
Causes
Ingestion of food (such as grains, cereals, and green vegetables) and cigarette smoke both have the potential to result in cadmium poisoning. It is also possible for workers in the plastics, battery, and metal plating industries to be exposed to cadmium.
Chromium Poisoning
Chromium is used in the production of automobiles, glass, ceramics, and linoleum. Excessive chromium exposure can lead to lung and respiratory tract cancer, as well as renal problems. Furthermore, chromium overexposure can produce gastrointestinal symptoms such as diarrhoea and vomiting, often with blood. Symptoms can include significant water-electrolyte imbalances, increased mild acidity of blood and body tissues (acidosis), and/or insufficient blood flow to tissues, causing shock. Lesions may form on the kidneys, liver, and the muscular layer of the heart (myocardium).
Cobalt Poisoning
Cobalt, which is used in jet engines, can induce nausea, vomiting, anorexia, ear ringing (tinnitus), nerve damage, respiratory disorders, an abnormally large thyroid gland (goitre), and/or heart and/or kidney problems.
Lead Poisoning
If sufficient safeguards are not implemented, lead production workers, battery plant employees, welders, and solders may be overexposed to lead. Although housed in the bone, lead can have an impact on any organ system. The severity of lead poisoning depends on the patient’s age and the exposure level.
Depending on the level of lead exposure, several symptoms might be seen in youngsters. Some affected people might not exhibit any observable symptoms. The onset of symptoms often takes three to six weeks. Overexposure to lead can make kids less energetic, clumsier, irritable, and sluggish (lethargic). Headache, nausea, stomach pain, anorexia, constipation, slurred speech (dysarthria), changes in kidney function, abnormally high levels of protein in the blood (hyperproteinemia), and unusually pale skin (pallor) brought on by a low level of iron in the red blood cells are some symptoms that can occur (anemia). Lead overexposure can cause neurological symptoms such as ataxia, which affects the capacity to coordinate voluntary movements, Brain damage (encephalopathy), seizures, convulsions, papilledema (Swelling of the optic nerve), enlargement of the optic nerve, and/or altered consciousness. Some of the affected children have behavioural or learning issues, including mental retardation and specific abnormalities in behaviour, cognition, language, balance, and school performance. Occasionally, symptoms could even be lethal.
Fanconi’s anaemia (a familial form of aplastic anaemia), is a blood condition. This condition causes nosebleeds and children can be easily bruised. It might result from interactions between genes and the environment. Acute lead poisoning can result in the acquisition of Fanconi’s syndrome rather than its inheritance.
Urine and faeces contain lead excretion. However, it can also be found in breast milk, sweat, saliva, hair, and nails.
Causes
Older homes may have lead paint that is degrading, which can contribute to lead poisoning by exposure (such as chewing or ingesting). Lead exposure at work may also occur in the fields of painting, smelting, firearms training, auto maintenance, copper or brass foundries, printing, battery production, mining, glass, gasoline, and bridge, tunnel, and elevated highway construction. Water tainted by lead pipes is another way that lead poisoning can occur. Calcium products, progressive hair dyes, kajal, surma, kohl, and digestive medicines are other sources of lead poisoning.
Diagnosis
With the help of specific laboratory tests for lead levels in the blood, the diagnosis of lead poisoning may be suspected. Other signs of lead poisoning include a rise in free erythrocytic protoporphyrins, ALA-D activity inhibition, elevated lead levels in hair, increased lead levels in deciduous teeth, estimation of urine coproporphytins, and zinc protoporphyrin levels. Lead poisoning can be diagnosed with the help of a spinal tap.
Manganese Poisoning
Many metals are produced using manganese as a purification agent. Overexposure to manganese can cause pneumonia and harm to the central nervous system, among other symptoms. Additional signs and symptoms include rigidity of the trunk, stiffness, awkwardness of the limbs, tremors in the hands, weakness, exhaustion, confusion, hallucinations, unusual or awkward gait, muscle spasms (dystonia), and psychiatric disorders.
Causes
Chronic intake and inhalation of manganese particles can result in manganese toxicity. Manganese exposure at work may also result from mining and processing manganese ore
Mercury Poisoning
Dental assistants and hygienists, as well as chemical workers, use mercury. Mercury can have an impact on the lungs, kidneys, brain, and/or skin. Fatigue, depression, sluggishness (letheragy), irritability, and headache are among symptoms of mercury toxicity.
Coughing, shortness of breath (dyspnea), tightness or searing pain in the chest, and/or respiratory distress are all signs of inhaling mercury vapours. Some affected individuals may develop abnormal fluid buildup in the lungs (pulmonary edoema), pneumonia, and/or aberrant fibrous tissue formation (fibrosis).
Overexposure to mercury poisoning may cause behavioural and neurological abnormalities such as excitability and rapid temper, lack of attention, and memory loss. Mercury poisoning can potentially cause shock and lasting brain damage. Some people who are impacted feel mental disorientation. A progressive cerebellar condition with poor coordination of voluntary arm movements (ataxia) may also be present. Abnormal involuntary movements of the body, such as uncontrollable jerky movements mixed with sluggish, writhing movements (choreoathetosis), are widespread. Non-inflammatory degenerative nerve disease (polyneuropathy); decreased capacity to coordinate voluntary movements (cerebellar ataxia); tremors of the legs, arms, and, in certain cases, the tongue and lips; seizures; and/or slurred speech are additional symptoms (dysarthria). Mood, behaviour, and consciousness changes may also occur.
In some situations of persistent inorganic mercury exposure, a personality disorder known as erethism or mad hatter syndrome may develop. Memory loss, extreme shyness, abnormal excitability, and/or insomnia are all symptoms of crazy hatter syndrome. This syndrome has been described in people exposed to mercury at work in the felt-hat industry.
Many affected people have sensory abnormalities such as contraction of visual fields, tunnel vision, and blindness, as well as hearing loss.
Skin abnormalities such as painful swelling and pink colouring of the fingers and toes (acrodynia); persistent redness or inflammation of the skin (erythema); high sensitivity (hyperesthesia) of the afflicted areas; and tingling and sensory issues may occur in some people.
Other affected individuals may develop stomach and intestinal abnormalities, kidney damage, dehydration, acute renal failure, gingivitis, severe local irritation of the mouth and throat accompanied by vomiting, and/or abdominal cramps with bloody diarrhoea.
Mercury is primarily eliminated in the urine and feces.
Causes
Exposure to significant amounts of mercury during the production of thermometers, mirrors, incandescent lights, x-ray equipment, and vacuum pumps may result in mercury poisoning. Contaminated fish and water are further contributors to mercury poisoning. Paint, calomel, teething powder, and mercuric fungicide used in diaper cleaning are some common sources of mercury exposure for kids. Exposure to mercury in thermometers, dental amalgams, and some batteries are other sources of mercury poisoning
Phosphorus Poisoning
Phosphorus poisoning symptoms include weakness, headache, vomiting, sweating, abdominal cramps, salivation, wheeze due to bronchial spasm, drooping upper eyelids (ptosis), pupil contraction (miosis), and/or muscular weakness and twitching. Furthermore, sensorimotor polyneuropathy (non-inflammatory degenerative illness of the sensorimotor nerves) might develop to progressive degeneration (atrophy). Respiratory paralysis may also develop in some circumstances.
Causes
Insecticides like tetraethylpyrophosphate, for example, may result in phosphorus toxicity.
Thallium Poisoning
Extreme drowsiness, stomach discomfort, nausea, vomiting, and bloody vomiting are all signs of thallium poisoning (hematemesis). Alopecia, a fast progressing and excruciating sensory polyneuropathy, motor neuropathy, cranial nerve palsies, seizures, an inability to coordinate voluntary movements (cerebellar ataxia), and/or mental retardation are some of the symptoms that some affected people may encounter. Eye symptoms can include the optic nerve losing away (atrophying), the optic nerve inflaming (retrobulbar neuritis), and the eyes’ muscles not working properly (ophthalmoplegia). In a few instances, thallium poisoning can worsen and cause cardiac and renal failure, disorientation, psychosis, organic brain syndrome, and/or coma.
Causes
Ingestion of rodenticides containing thallium has the potential to result in thallium poisoning. In addition to consumption and inhalation, thallium in herbicides, insecticides, metal alloys, and fireworks can also be absorbed through skin.
Additional Metal Poisonings
● Antimony, aluminium, barium, bismuth, copper, gold, iron, lithium, platinum, silver, tin, and zinc are more metals that can poison people. GI, renal, and neurological symptoms, such as headache, irritability, psychosis, stupor, coma, and convulsions, may be common signs of poisoning from these metals.
● Lead is hardened with antimony, which is also used to make batteries and cables. It might probably result in skin cancer and lung illness, especially in smokers.
● The production of electrical cables uses copper. Metal fume illness, a flu-like reaction, and blood abnormalities could result from overexposure of it. An excessive amount of copper is stored in the body’s tissues, particularly in the liver, brain, and eye corneas, which is a symptom of Wilson’s disease, a genetic illness. The condition is brought on by a metabolic abnormality and does not result from excessive copper exposure.
● Pharmaceuticals and glasses both contain lithium. Diseases of the kidneys, central nervous system, gastrointestinal tract, and stomach may be brought on by lithium..
● Overexposure to silver can make the skin, hair, and internal organs turn in grey colour. Diarrhea, vomiting, and nausea may also be present.
● Metal fume fever, stomach and intestinal problems, and/or liver malfunction can all result from excessive zinc exposure.
● An excessive amount of bismuth exposure can result in somnolence, acute sleepiness, and neurological disorders such ataxia, hallucinations, delusions, myoclonic jerks, tremors, seizures, and the inability to stand or walk.
● Skin rashes, bone marrow depression, stomach and intestinal bleeding, headache, vomiting, focal or generalised continuous fine vibrating muscle movements (myokymia), and yellowing of the skin (jaundice), mucous membranes, and whites of the eyes may result from excessive exposure to gold (as in the treatment of rheumatoid arthritis).
● Overexposure to nickel has been linked to an increased risk of lung cancer in some circumstances.
● Overexposure to selenium can harm peripheral nerves, irritate the gastrointestinal tract, respiratory system, and eyes, as well as induce liver inflammation, hair loss (alopecia), depigmentation, and liver damage.
● Tin overexposure can harm the nervous system and result in psychomotor disorders as tremor, convulsions, hallucinations, and psychotic behaviour.
● Aluminum containers are used for water filtration as well as in the production and processing of several foods, medications, and cosmetics. Aluminum overexposure could harm the brain (encephalopathy).
Treatment
Preventing exposure to the metal is the basic treatment for heavy metal toxicity. The use of various chelating agents, which induce the toxic (poison) element to join with the medicine and be eliminated in the urine, is another method of treatment. BAL (Dimercaprol) is one of three commonly used medications to treat metal poisoning. Others two common antidotes are Penicillamine, and Calcium EDTA (Calcium Disodium Versenate). Each of them functions by binding the metals, allowing their removal from the body through urination.
Treatment must also address symptoms and provide emotional support. Some ingested metals can be removed in some situations by pumping the stomach (gastric lavage). The medicine succimer (Chemet), which was licenced by the FDA in 1991, is used to treat children who have severe lead poisoning. When someone has inhaled poison, they should be evacuated out of the polluted area and given support for respiration and ventilation. Heavy metal exposure at work must be prevented through the use of masks and protective gear. Brain swelling (cerebral edoema) calls for treatment with the diuretic Mannitol, corticosteroid medications, and intracranial monitoring. Hemodialysis and/or other specialised treatments may be necessary in cases of kidney failure.
Note: Do not attempt to identify or treat heavy metal poisoning on your own if you suspect you may have it. Visit your physician instead.
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