What is Cobalt Toxicity (Toxic Levels of Cobalt)?
Cobalt is a gray, magnetic metal that is pliable or bendable. It’s part of the natural world, found in various minerals alongside other elements like copper, nickel, and sulfur. Because cobalt can withstand high temperatures and has a natural magnetic pull, it’s commonly used in industries to make hard metals and advanced alloys. For instance, Alnico, an alloy made of iron, aluminum, nickel, and cobalt, is used for its long-lasting magnetism. Cobalt also used in the making of tungsten carbide, a material known for its hardness, heat resistance, and strength.
In the past, a compound called cobalt chloride was used to treat low red blood cell count or anemia, due to its ability to encourage the production of red blood cells. However, because it can lead to thyroid issues and goiter, it’s no longer commonly used for this purpose. An important compound that contains elements of cobalt is called cyanocobalamin, also known as vitamin B12.
Vitamin B12 is an essential nutrient usually found in meat, dairy, eggs, fish, and poultry. Not having enough vitamin B12 can lead to serious anemia and peripheral neuropathy, which is damage to the nerves in your arms and legs. Hydroxocobalamin, which comes before vitamin B12, is used as an antidote for cyanide poisoning and may be helpful in treating vasoplegic shock, a severe drop in blood pressure.
There are several ways people may be exposed to cobalt: by mouth, through the skin, or by breathing it in.
What Causes Cobalt Toxicity (Toxic Levels of Cobalt)?
Cobalt, a type of element, is found in many forms such as pure cobalt, inorganic salts, and organic cobalt. It’s used in a wide array of items and industries, such as in artist paints, dyes, porcelain, cement, rubber, drill production, and even medical implants like dental hardware and orthopedic implants. Cobalt is also found in some vitamins like Vitamin B12.
Cobalt can be harmful if inhaled from the air in workplaces where it’s used, like factories. Cobalt in forms like cobaltous chloride or cobaltous sulfate are generally more harmful compared to organic cobalt. Though Vitamin B12 contains cobalt, it’s considered relatively safe as the body doesn’t absorb much of it when consumed.
There isn’t a known harmful dose of cobalt, as it can vary greatly. For example, some people drinking beer with cobalt sulfate were consuming 6 to 8 mg per day for several weeks or months and developed severe symptoms, with some even dying. In contrast, infants with anemia taking 40 mg of cobaltous chloride per day for three months didn’t show any harmful effects. This shows other factors can influence how the body reacts to cobalt, not just the amount consumed.
Risk Factors and Frequency for Cobalt Toxicity (Toxic Levels of Cobalt)
In the past, people were exposed to cobalt through the treatment of anemia with cobalt chloride and by consuming beer that contained cobalt sulfate as a foam stabilizer. Nowadays, cobalt exposure can come from sources like chemistry sets, dyes, mining, and orthopedic implants. The major source of cobalt exposure, though, is found in the creation of the hard metal tungsten carbide.
Between the 1950s and 1970s, there were several epidemics of “cobalt-induced goiter and cardiomyopathy”. The first identified cases took place in Nebraska in the year 1966, with 64 cases and 30 deaths. Following this, were 48 additional cases in Quebec with a 46% death rate, and 20 more cases in Minneapolis from 1964-1967 with a 43% death rate. It was discovered that the individuals affected in these cases drank beer regularly that had cobalt sulfate foam stabilizer added and they were malnourished.
In the general population, the most common source of cobalt likely comes from dietary supplements. Factories that improperly dispose of cobalt or tungsten carbide can cause environmental pollution and expose nearby inhabitants. Tungsten carbide, a hard metal, is made by heating powdered cobalt and tungsten at a temperature of 1550 degrees Celsius (2822 degrees Fahrenheit) in the presence of hydrogen. Studies have proven that the concentrations of cobalt and tungsten in the air within these factories can be ten times higher than the quantities in the ordinary atmosphere.
People can also be exposed to cobalt through jobs that involve maintaining hard-metal blades and polishing diamonds. As a result of cutting and polishing, people may inhale cobalt in the form of an aerosol, leading to hard metal disease (HMD). Cobalt exposure at work may also commonly lead to asthma, either alone or when working with tungsten carbide.
- The exact incidence of HMD is unclear. In one study, out of 320 patients who visited an occupational respiratory clinic over three years, five were diagnosed with HMD.
- In another study, out of 290 exposed workers, 11 were found to have abnormalities on their lung x-ray.
- Also, there were 22 reported cases of asthma caused by cobalt over a period of 36 years.
More recently, concerns have been raised about the potential use of cobalt salts by athletes looking for a competitive edge. They may use it to promote the production of red blood cells, a technique known as “blood doping”. However, due to the potential harmful effects, this is not an ideal method of enhancing performance.
Signs and Symptoms of Cobalt Toxicity (Toxic Levels of Cobalt)
Cobalt toxicity is a rare condition that shares many symptoms with more common diseases, making it challenging to diagnose. Consuming cobalt salts and elemental cobalt can result in discomfort in the digestive system, likely due to direct irritation. It is important to have a thorough understanding of a person’s occupation, diet, and surgery history to pinpoint the possible source of cobalt exposure.
People working in hard metal manufacturing and diamond polishing are at a significant risk of developing cobalt toxicity, specifically a lung condition called hard metal lung disease. They may experience shortness of breath, cough, and wheezing. Those who have cobalt toxicity due to a joint replacement may experience nerve dysfunction, eye problems, cognitive decline, low thyroid hormone levels, and heart muscle disease.
These symptoms can develop long after the joint replacement surgery, and can include general complaints such as pain, swelling, and difficulty walking. Additionally, cobalt can cause skin inflammation in some individuals, particularly those exposed in a professional setting. It’s worth noting that, at this time, evidence suggests cobalt does not lead to kidney toxicity, birth defects, or fertility problems.
- Discomfort in the digestive system from consuming cobalt salts and elemental cobalt
- Shortness of breath, cough, and wheezing in people working in metal manufacturing and diamond polishing
- Nerve dysfunction, eye issues, cognitive decline, low thyroid levels, and heart muscle disease in people with cobalt joint replacements
- General pain, swelling, and walking difficulty, usually long after the initial joint replacement surgery
- Skin inflammation, particularly in individuals exposed to cobalt in a professional setting
Testing for Cobalt Toxicity (Toxic Levels of Cobalt)
Consulting with a Poison Control Center or a medical expert, specializing in toxicology, can help guide the medical tests and treatment needed when dealing with possible cobalt poisoning.
Measuring the amount of cobalt in body fluids isn’t commonly possible, so in emergency situations, doctors often rely on other tests that might indicate cobalt toxicity. These tests measure blood parameters (like the complete blood count, reticulocyte count, erythropoietin, and thyroid-stimulating hormone levels). Severely ill patients might show signs of metabolic acidosis and increased lactate levels. Electrocardiograms, echocardiograms, and troponin tests can help identify heart issues, like cardiomyopathy.
To detect lung issues, especially in people exposed to cobalt in their jobs, doctors can use chest x-rays and CT scans. For non-urgent cases, lung function tests can reveal a reduction in vital breathing capacity.
If a patient might have problems with cobalt-containing joint replacements, imaging tests might help to identify people at high risk of toxicity. Ultrasound and MRI scans are especially good at examining cobalt implants. However, these imaging tests can’t directly diagnose cobalt toxicity – they can only help spot signs of tissue reactions and implant failure.
To monitor people exposed to cobalt at work, doctors usually measure the amount of cobalt in the urine. The typical range of cobalt in blood is reported to be 0.1 to 1.2 mcg/L, and in urine, it’s 0.1 to 2.2 mcg/L. Since people’s bodies naturally remove substances at different rates, understanding the concentration of cobalt involves knowing the amount and length of time of exposure. Testing the whole blood levels is generally considered the best way to understand the body’s overall exposure to cobalt.
More recently, cardiac MRI has been used to diagnose heart damage caused by cobalt in metal-on-metal hip replacements.
Treatment Options for Cobalt Toxicity (Toxic Levels of Cobalt)
The main way to treat cobalt poisoning is through supportive measures. If someone comes in with acute symptoms, they’ll need urgent care to reduce the amount of cobalt in their system. While there aren’t any studies focused solely on how to remove cobalt from the digestive system, they likely use the same methods used for most other metal poisonings. For example, inducing bowel movements can be useful, particularly if X-rays show metal objects. If the cobalt consumed was liquid, washing out the stomach might be helpful. However, if it was solid, this method is less likely to be beneficial. If the person is feeling nauseous or throwing up, medications to alleviate these symptoms can be used.
Chelation therapy, which involves using specific substances to bind to the cobalt and help the body excrete it more quickly, isn’t thoroughly studied in people. Most data comes from animal studies and patient case reports. At present, it’s thought calcium disodium ethylenediaminetetraacetic acid and N-acetylcysteine might be the best options for chelation therapy. Usually, N-acetylcysteine isn’t used for this purpose, but it has a specific group on its molecule that can bind to cobalt.
Chelation therapy is not likely useful until the source of cobalt has been removed. This may include removing an artificial joint if it’s causing the toxicity. You might need chelation if the cobalt is affecting your organs badly, like if you have severe acidosis or heart failure.
To prevent cobalt poisoning due to work exposure, the best method is simply to avoid cobalt. Improvements in ventilation systems at workplaces have dramatically reduced toxicity from exposures. If someone has lung disease or asthma triggered by cobalt, they might find corticosteroids helpful, along with avoiding any further exposure to cobalt.
What else can Cobalt Toxicity (Toxic Levels of Cobalt) be?
Cobalt poisoning is not common and it is usually caused by ingestion. The symptoms are often similar to the ones experienced from gastrointestinal problems or from other heavy metal poisonings. This can make it difficult to diagnose, especially if the doctor doesn’t have detailed medical history.
People who work in certain jobs, like tungsten carbide manufacturing, may get sick from cobalt exposure. If your job exposes you to cobalt and you start to have breathing problems, your doctor should check whether you have a lung disease called pneumoconiosis, or the so-called “hard metal disease”.
Cobalt poisoning should also be considered in patients who come in with high red blood cell counts (polycythemia) or enlarged thyroid (goiter).
If you’ve had hip replacement surgery, and you’re experiencing heart muscle disease symptoms (known as cardiomyopathy), your doctor should check whether you’ve been exposed to cobalt toxicity. The type of artificial joint used in your surgery could provide clues to the cause of your symptoms.
What to expect with Cobalt Toxicity (Toxic Levels of Cobalt)
Acute cobalt toxicity, an extreme reaction to cobalt, can lead to serious illness, especially for patients with heart muscle disease, as it’s linked to a high mortality rate. There’s little data on using chelation—a medical procedure that removes heavy metals from the body—for treating non-arthroplastic cobalt toxicity. However, case reports suggest that chelation could improve recovery from heart muscle disease in patients with cobalt toxicity related to artificial joint implants.
Early diagnosis and replacing the artificial joint can influence the prognosis of cobalt toxicity from artificial joints, as it effectively reduces cobalt levels in the blood and serum, often resulting in the patient’s clinical recovery.
How much a patient recovers seems to depend on how long they were exposed to high amounts of cobalt. In certain instances, even after the chelation treatment and joint removal, some patients don’t fully recover. They may continue to experience symptoms ranging from ringing in the ears and hearing loss, to heart muscle disease that may require the implantation of a device to assist the function of the left side of the heart.
Patients suffering from hard metal lung disease, a rare form of lung disease caused by cobalt, often recover once the source of exposure is eliminated.
Possible Complications When Diagnosed with Cobalt Toxicity (Toxic Levels of Cobalt)
Not identifying cobalt toxicity in time can lead to serious health issues and a difficult recovery process. These health concerns may include heart muscle disease (cardiomyopathy), nerve damage in the body’s periphery (peripheral neuropathy), loss of vision, and long-term lung conditions (chronic respiratory disease).
The International Agency for Research on Cancer (IARC) points out that pure cobalt metal can be potentially cancer-causing to humans (Group 2B).
When cobalt is combined with tungsten carbide, it’s rated as likely to be cancer-causing (Group 2A). While human data is limited, some animal studies show a risk of certain types of cancers such as soft tissue sarcomas and lung cancer.
Preventing Cobalt Toxicity (Toxic Levels of Cobalt)
Cobalt poisoning usually happens when people use a metal-on-metal joint replacement or when they come into contact with it in their workplace. It’s really important to use the correct protective equipment and stick to the safety rules in the workplace to lessen contact with cobalt and a material called tungsten carbide, which often shows up in the form of dust or tiny scraps.
Lessening contact with these materials can help prevent future health problems. If you have a metal-on-metal hip replacement, you should definitely talk about your worries with your doctor, especially if you start to experience new pain, swelling, or trouble walking. These symptoms could mean you’re at a greater risk of becoming poisoned by the substances used in the implant.
