What is Cadmium Toxicity?
Cadmium is a type of heavy metal that can cause harm to people in various ways. You often find it mixed with other heavy metals such as zinc, copper, and lead. The amount of cadmium can increase due to things like disruption of the soil and volcanic activity, and it can also be a byproduct of industrial processes. In industry, cadmium is most commonly used for adding a protective coating to metals (a process known as electroplating) and for making nickel-cadmium batteries.
What Causes Cadmium Toxicity?
Cadmium toxicity, or getting sick from too much exposure to the metal cadmium, typically happens through work, environmental factors, or hobbies. Environmental exposure can happen when soil is contaminated with the metal, and the food grown in that soil is then eaten. This kind of contamination often occurs in places where mining or refining of ores happens.
One famous example of this happened in Japan back in the 1950s at the Jinzu River when a mine released a large amount of cadmium into the environment. The rice that was grown in that area caused an outbreak of a very painful bone condition mostly in women who had multiple births and were postmenopausal. This condition was named “itai-itai” disease, which translates to “ouch-ouch” in English, because the people affected would say this every time they took a step.
Risk Factors and Frequency for Cadmium Toxicity
People who work with metals like welders, solderers, and jewelry workers are exposed to a risk of inhaling fumes containing cadmium oxide. This becomes significantly toxic when they work in confined spaces that lack proper ventilation.
Signs and Symptoms of Cadmium Toxicity
Acute poisoning can happen if you breathe in fumes containing cadmium or eat something containing cadmium salts. This can closely resemble a condition called metal fume fever. Symptoms like fever, chills, cough, and breathing difficulty may surface within six hours of being in contact with cadmium, for example, while soldering with alloys containing cadmium. People might initially feel okay, but the situation can escalate to severe lung inflammation (pneumonitis) and acute respiratory distress syndrome (ARDS), sometimes leading to death within 3-5 days. Survivors may end up with a long-term lung condition.
Acute poisoning due to ingesting cadmium is less common than through inhalation. Ingestion can cause damage to the digestive system. In severe cases, it can lead to destructive bleeding in the digestive tract and failure of multiple organs.
In cases of chronic cadmium exposure, certain long-term health issues can arise:
- Damaged kidneys, resulting in long-term proteinuria, which is excessive proteins in urine. This condition can progress even when not in contact with cadmium anymore, especially in people with kidney disease or conditions like diabetes that increase the risk of kidney disease. Cadmium has also been linked to high calcium in urine and kidney stones.
- It’s unclear whether chronic inhalation of cadmium causes lung toxicity. However, it is accepted that it can lead to lung cancer.
- Painful bone softening (osteomalacia) often occurs in postmenopausal women due to environmental exposure to cadmium. This explains why there are fewer cases among occupational workers who are typically younger males.
- Although liver toxicity hasn’t been reported with cadmium exposure, problems with brain function such as parkinsonism, impaired cognition, and smell problems can occur. Certain animal studies suggest that cadmium may also be linked with high blood pressure, weakened immunity, and testicular dysfunction, but these findings have not been directly transferred to human cases.
Testing for Cadmium Toxicity
If doctors suspect that a person has been exposed to cadmium, a metal often found in industrial workplaces, they don’t usually rely solely on measuring the amount of cadmium in the blood to confirm this. This is because blood tests for cadmium are not always reliable, especially if the exposure did not happen recently. Instead, they often depend on the person’s history, a physical exam, and the symptoms they are experiencing.
If the exposure to cadmium has been occurring over a long period of time, a urine test is a better choice for figuring out the total amount of cadmium in the person’s body. In fact, people who are at a high risk of being exposed to cadmium on a frequent basis, such as those who work in certain industrial occupations, should routinely have their urine tested for a particular protein (beta-2-microglobulin). This protein can indicate if the kidneys have been damaged due to prolonged exposure to cadmium.
Treatment Options for Cadmium Toxicity
Inhaling cadmium, a toxic metal, can be harmful to your lungs. If this happens, it’s crucial to manage your breathing and you might need extra oxygen to help. Steroids are often used as a treatment option, but it’s still uncertain how much they actually help.
If you accidentally swallow cadmium, the situation is a bit different. For this, healthcare providers may use treatments like activated charcoal or gastric lavage, a procedure that cleans out your stomach. After this, they’ll need to keep a close eye on you for any signs of stomach, liver, or kidney damage. Chelators are a type of medicine that can attach to cadmium and help remove it from your body, and these could be promising, but their benefits in cadmium poisoning are not yet confirmed. However, some studies suggest that a specific chelator called succimer could provide good results if given early in the treatment course.
In the case of chronic poisoning, where you’ve been exposed to cadmium over a long period, usually, the first step is to stop any further exposure to cadmium. While the damage from chronic cadmium poisoning could be permanent and can continue to worsen over time, using chelators is currently not recommended for these situations.
What else can Cadmium Toxicity be?
If you’ve been exposed to metals in your everyday or work environment, doctors need to check for potentially harmful metals in your body. These might include:
- Iron
- Lead
- Arsenic
- Mercury
- Thallium
In cases of sudden (or acute) toxic exposure, other diseases could cause lung inflammation and difficulty breathing. This includes a condition called “metal fume fever,” which is usually diagnosed once other possible causes have been ruled out.
What to expect with Cadmium Toxicity
In the case of sudden, or ‘acute,’ exposure, lung disease that restricts normal breathing functions can be a lifelong issue. On the other hand, with long-term or ‘chronic’ exposure, damage to the kidneys can worsen progressively over time and become irreversible.
Preventing Cadmium Toxicity
If you’re exposed to cadmium at work or during your hobbies, it’s important to let your doctor know. Cadmium exposure can affect your lungs, bones, and nervous system, so you may need to be checked for related symptoms regularly. Urine tests can be used to look for proteinuria – an excess of protein in your urine which can indicate a kidney disease. Additionally, lung screenings might be needed to check for cancer. You should also undergo tests to ensure your bones, heart and blood vessels, nervous system, and reproductive organs are functioning properly. Regular check-ups can help prevent severe health issues.
