Testing For Heavy Metals

A heavy metals panel is used to detect and measure the level of different types of heavy metal in the body. Tests like these are usually conducted using urine or blood. However, the lab may use hair, fluid, or body tissue, as well, depending on the purpose of the test. Most labs have a variety of heavy metal panels available, each designed to test for different types of metal. Some of the metals that are commonly tested for include:

  • Arsenic
  • Mercury
  • Lead

Other metals that are frequently tested for using panels like these include zinc, copper, and cadmium. A qualified healthcare provider determines which test to order, typically basing the decision on their patient’s symptoms or on the likelihood that they were exposed to certain types of metal. 

The phrase “heavy metals” is used to describe metallic or dense elements in the periodic table. Elements like these not only occur naturally throughout the world but are also used when manufacturing many different types of products. The body requires small amounts of certain heavy metals. Examples of metals that are beneficial in trace amounts include copper, zinc, iron, selenium, and molybdenum. While these elements are helpful at extremely low levels, they can be harmful at higher concentrations.

When the body contains too much of any heavy metal, it can cause damage or irritation. Heavy metals also can contribute to environmental contamination, affecting everything from the air and soil to water and food. Once these metals enter the environment, they usually remain there forever. Since elements like these can cause harm, they are sometimes referred to as “toxic metals.”

Different types of metal can cause various symptoms. The symptoms a patient experiences can also vary based on the concentration of the metal, the amount of time they were exposed to it, how they were exposed, how old they are, and their overall level of health. Certain metals pose a greater risk than others. Different types of the same metal may also vary in terms of how toxic they are. For instance, an inorganic metal compound may be more or less harmful than its organic counterpart.

The method of exposure affects how much of the metal is absorbed by the body and which parts of the body are impacted. For instance, a metal that is harmless when touched or swallowed could be severely damaging to the lungs if it is inhaled.

Acute heavy metal exposure can damage the body, sometimes even causing death. The human body is capable of processing relatively low amounts of heavy metals. Exposure to higher concentrations of these metals, however, can cause them to build up in the liver, kidneys, brain, or skeletal system. Even low levels of exposure should be carefully tracked to monitor for any potential problems.

Exposure to certain metals may lead to a greater likelihood of getting cancer. Other metals impact the production of both white and red blood cells. Babies who are still in the womb and small children are most likely to develop problems when exposed to heavy metals, even at relatively low concentrations. Exposure to these metals can impact the mental and physical development of the child, causing irreversible damage to the brain and other organs in the body. Heavy metals can be transferred to developing fetuses from the mother. In some cases, infants can also be exposed through breastmilk.

What Sample Collection Techniques Are Used?

The sample collection method depends on the type of testing. For blood tests, the blood is taken from a vein in the arm using a needle. For urine tests, the lab requires a 24-hour urine collection. Special containers that don’t contain metal are used for collection to keep the sample from becoming contaminated.

Blood tests and urine samples are both effective when testing for toxic metals, although the forms of metal that they test for can vary. For example, a dangerous type of mercury that is commonly found in large fish shows up on blood tests but doesn’t appear in urine samples. On the other hand, urine testing is the most effective way to test for inorganic mercury or to measure arsenic levels in the body.

Analyzing the fingernails or hair can show whether or not a person was exposed to heavy metals in the past. However, these methods don’t provide any information about the exposure that occurred recently. By testing either urine or blood samples, the lab can identify both recent and long-term exposure to potentially harmful metals.

Although tissue samples aren’t used very often, there are certain situations where a biopsy may be taken.

How Should You Prepare For The Test?

During the 48 hours leading up to the test, avoid eating fish or other types of seafood. Wait a minimum of 96 hours before having a sample collected if you have undergone a medical procedure that used contrast media that contained either iodine or gadolinium.

Heavy metal panels are used to determine the concentration of toxic metals in people who have been exposed to potentially harmful metals. Tests like these are also used to track heavy metal concentrations in workers who are regularly exposed to toxic metals. Examples of jobs where this type of testing may be necessary include mining, carpentry, radiator repair, and gun ranges. A special treatment known as chelation therapy is used to lower the concentration of heavy metals in the body. Heavy metal panels are used to keep track of how effectively the therapy is working.

A typical heavy metal panel includes several types of tests, each designed to look for different metals. Typically, the tests are grouped based on whether they are measured through the blood or urine. A doctor or healthcare provider chooses the heavy metal panel based on the type of exposure their patient experienced or the symptoms that they are demonstrating. The most common metals included in panels like these are:

In situations where the healthcare provider believes that the patient has been exposed to a certain type of metal, they may order an individual test for that type of metal. The test for lead exposure, for instance, is usually run on its own. This is particularly true when testing children since they are at a higher risk of developing problems as a result of lead exposure. Tests involving fingernails, hair, fluids, or tissues of the body are typically ordered on their own rather than as part of a panel, as well.

What Are Some Common Situations Where Heavy Metals Panels Are Ordered?

If a medical provider believes that one of their patients has been exposed to heavy metals, they will typically order a heavy metals panel. Exposure to heavy metals can also cause symptoms, varying in type and severity based on the kind of metal and the concentration of the exposure. Early on, the symptoms of heavy metal exposure are easy to overlook since they aren’t very specific. Unfortunately, organ damage can occur even if a patient isn’t displaying any distinct symptoms. Signs to watch for that could indicate heavy metal poisoning include the following:

  • Pain in the abdomen
  • Diarrhea, nausea, or vomiting
  • Problems involving the nervous system, including weakness, tingling, or numbness in the extremities.
  • Kidney or liver damage
  • Anemia
  • Fluid in the lungs
  • Lung irritation
  • Memory problems or other cognitive issues
  • Horizontal lines on the fingernails, which are known as Mees lines
  • Behavioral changes
  • Weak or deformed bones in young children
  • Miscarriage or early labor in women who are pregnant

Typically, workers who come in contact with heavy metals on the job undergo routine monitoring. There are also safety protocols in place that are designed to reduce the risk of metal exposure for employees. Many heavy metals that are used in work-related applications are regulated and monitored by the U.S. Occupational Safety and Health Administration (OSHA). Anytime levels of these metals climb too high, steps are taken to reduce employee exposure levels and to monitor their systems for problems.

How Are The Test Results Interpreted?

Interpreting the results of a heavy metals panel isn’t as straightforward as it might seem. Even if the test shows that the levels of a particular heavy metal are low in the blood, too much exposure may still have occurred. Heavy metals don’t remain in the urine or blood for very long. For example, lead enters the organs from the blood. With long-term exposure, it also finds its way into the bones. Chronic lead exposure could cause a patient to have lead in their urine, blood, bones, and internal organs.

Even patients who seem healthy may have small amounts of heavy metal present in their urine or blood. Metals like these exist naturally in the world. The maximum safe level of exposure can vary depending on how old the patient is. As scientists learn more about the safety of certain metals, the recommendations regarding exposure also may change.

The US Centers for Disease Control and Prevention (CDC) found that 8,000 people who participated in a 2004 study had measurable amounts of mercury in their bodies. The study found that the amount of mercury in the urine and blood increased as people got older. According to the CDC, small amounts of mercury in the urine or blood don’t negatively impact health. Conducting studies like these, however, allows researchers to establish the average amount of mercury that most people have in their blood or urine. This makes it easier for doctors or medical practitioners to identify whether their patients have experienced higher-than-average exposure to mercury when compared to the general public.

The Agency for Toxic Substances and Disease Registry (ATSDR) has a section on its website titled ToxFAQs, where they provide detailed information about different metals, including the level of risk associated with the metal and its effect on health.

What Other Information Should I Know About Heavy Metals?

Everyone’s body processes heavy metals differently. The rate at which the metals are absorbed and eliminated can vary from one person to another. That means that two people who are exposed to the same type and amount of a particular heavy metal may not experience the same symptoms. People who have existing problems with their health may have an increased risk of suffering ill effects from heavy metal exposure.

Trace levels of heavy metals are carefully tracked. Steps are taken to keep exposure to these metals to a minimum. Despite that, avoiding heavy metals completely is unfeasible. For example, arsenic occurs naturally in drinking water in certain areas. Thermometers and fluorescent light bulbs contain low levels of mercury. Anytime these items break, the mercury can potentially find its way into the environment. Bacteria that are found in water produce an organic type of mercury known as methylmercury. This mercury can accumulate in fish. The level of mercury concentration depends on where the fish are located and how large they are. Usually, old, large fish contain the most methylmercury. In general, the risk of consuming too much mercury is extremely small, especially when compared to the health benefits of consuming fish. Pregnant women should be cautious when eating fish. According to the March of Dimes, women who are pregnant should not eat some types of fish until after they give birth. This reduces the risk of mercury harming their unborn child.

At one time, lead was commonly used in household plumbing, paint, and gasoline. While this type of environmental lead exposure is declining, old homes and buildings can still have high levels of lead in their plumbing and paint. In 2015, the town of Flint Michigan failed to keep lead from contaminating the water when they changed their water source. Switching from getting their water from Detroit to getting it from the Flint River without taking measures to prevent corrosion lead to major problems for the residents. As the river water made its way through the pipes, it corroded them, causing lead to find its way into the local water supply, making it dangerous to drink.

Over time, as house paint breaks down, the paint dust and chips can contaminate the soil around the building. Young children have the greatest risk of developing health problems as a result of exposure to lead. Children may put their mouths on surfaces that are painted, or they may consume paint chips. When playing, they may inadvertently be exposed to the soil that is contaminated, or they may breathe in dust that contains lead.

Lead isn’t the only heavy metal that can pose a problem. Cadmium and arsenic contamination have also been found on jewelry and toys in the past.

Three government agencies are responsible for monitoring heavy metal sources in the environment, including in the water, air, and supply of food. These agencies include the Environmental Protection Agency (EPA), the Food and Drug Administration (FDA), and the Centers for Disease Control and Prevention (CDC). The EPA is responsible for regulating emissions, establishing upper exposure limits for heavy metals, and tracking how heavy metal exposure is affecting the population. The FDA is tasked with controlling toxic metals in food. The CDC advises parents to test their children for exposure to lead, particularly if they spend a lot of time in houses or buildings that were constructed before 1978.