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Perchlorates are colorless and odorless salts. Perchlorate is a negatively charged molecule made of four oxygen atoms and one chlorine atom. They quickly dissolve in water. This is why manufacturers use them to make explosives and related products.

Perchlorates can be natural or man-made. They are found in the Southwest United States, including Southern California and Nevada. Manufacturers also find them in Canada, Chile, and other parts of the United States.

Most people have no idea what perchlorates are. Fewer realize that they can be dangerous for humans. Here, we'll explain what perchlorate salts are and how they can affect your health. We'll also briefly discuss what to do if you or a loved one become sick after perchlorate exposure.

What Are Perchlorates?

Perchlorates are molecules that contain oxygen and chlorine. Many foods contain natural perchlorates, such as:

  • Greens
  • Salami
  • Bologna
  • Macaroni and cheese
  • Bagels
  • Chocolate

While you may encounter these chemicals in food, they are also in products like fireworks and road flares. Manufacturers use perchlorates for industrial products as well. For instance, rocket propellants contain perchlorates. So do explosives.

Manufacturers produce five main types of perchlorates:

  • Ammonium perchlorate
  • Magnesium perchlorate
  • Sodium perchlorate
  • Potassium perchlorate
  • Lithium perchlorate

Perchlorates naturally occur in saltpeter deposits in Chile, among other places. Companies use saltpeter to make fertilizer. Manufacturers also use perchlorates to make other chemicals.

Products Containing Perchlorates

Perchlorate isn't like asbestos. You won't find it in hundreds of household products. You will typically find them in industrial products and explosives.

Some of the products that contain perchlorates include the following:

  • Rocket fuel
  • Fireworks
  • Firecrackers
  • Road flares
  • Industrial explosives

The U.S. Environmental Protection Agency (EPA) regulates the use of perchlorates in manufacturing. But experts still aren't sure what levels of perchlorates are safe. This is why the government is still studying the effects of these chemicals. The EPA plans to amend the Safe Drinking Water Act once it does further research.

Safe Drinking Water Act and Perchlorates

The U.S. EPA regulates the use of perchlorates in manufacturing. They also set maximum contaminant levels for companies that use perchlorates for industrial purposes. Following a federal court order, the agency committed to updating perchlorate drinking water regulations by November 2025. They must also amend them again in 2027 to define new perchlorate guidelines.

The primary concern of the court order is the contamination of surface and drinking water. The health risks of perchlorate contamination are severe. Long-term perchlorate exposure can cause serious health conditions.

Perchlorate Contamination and the Environment

Perchlorates enter the environment near sites where companies make and test rockets. Factories that use perchlorates may also seep them into water and soil.

Perchlorates wash away with rainwater. This means they end up in groundwater eventually. Scientists are still determining how long they will stay there. But studies suggest these chemicals remain in the water for a long time.

The odds of perchlorates entering your drinking water are high. The good thing is that they tend to remain in low concentrations. This doesn't mean that they don't pose a threat to human health. Pregnant women, for example, are at a high risk of perchlorate toxicity. So are their unborn fetuses.

Perchlorate exposure can cause damage to the thyroid. For adults, this can cause problems with metabolism. For unborn babies and infants, perchlorate exposure can cause growth and developmental problems.

Perchlorate Exposure and Public Health

The FDA and the U.S. Food and Drug Administration regulate the use of perchlorates. These chemicals threaten both human and environmental health.

Perchlorate exposure may occur in the following ways:

  • Drinking water contaminated with perchlorates (water supplies near hazardous waste sites may contain perchlorates)
  • Eating food or milk containing perchlorates
  • Living close to factories that make flares, fireworks, and other explosive devices
  • Smoking or chewing tobacco
  • Living near a rocket testing or manufacturing facility

Perchlorate exposure can interfere with your thyroid hormone levels. It also impacts your body's iodine intake. When you realize you're sick, the damage may be severe. This is why the government performs risk assessments to identify high-risk areas.

Adverse Health Effects of Perchlorate

The adverse health effects of perchlorate salts are due to perchlorate itself. Other components, such as magnesium or lithium, aren't the problem. Perchlorates threaten human health when they enter drinking water supplies.

Perchlorate affects the thyroid gland's ability to uptake iodide. Iodide is an important chemical our bodies need to produce hormones that regulate many bodily functions. People exposed to high concentrations of perchlorate may develop a low level of thyroid activity (hypothyroidism).

Low blood levels of thyroid hormones can damage various parts of our body, including:

  • Kidneys
  • Blood
  • Skin
  • Skeleton
  • Pulmonary system
  • Gastrointestinal tract
  • Liver
  • Neuromuscular system
  • Cardiovascular system
  • Central nervous system
  • Reproductive system
  • Endocrine organs

Studies show that health problems are unlikely at lower levels of perchlorate exposure. For instance, one study found that exposure to perchlorates for two weeks did not impact the function of participants' thyroid glands.

Other studies involving people who spent years working with perchlorates had no problems with their thyroids, livers, kidneys, or blood. This doesn't mean that perchlorates don't cause iodine deficiencies or other health problems. Low levels of perchlorates may not be as harmful as experts thought.

Perchlorates and Cancer

There haven't been any studies on whether perchlorate exposure causes cancer in humans. Studies have found that long-term exposure to perchlorates can cause thyroid cancer in mice and rats. Despite this evidence, the National Academy of Sciences (NAS) concluded that humans are unlikely to share the same risk as rats. There are too many biological differences.

The Department of Health and Human Services (DHHS) has not classified perchlorates as carcinogens. The same applies to the U.S. Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC).

Perchlorates and Your Health

The chances of your house containing perchlorates are low. You should be more concerned with perchlorate exposure through your tap water. If you worry about the safety of your drinking water, stick to bottled water.

You should also monitor your children to ensure they don't play with or eat dirt. Children are more vulnerable to dangerous perchlorate exposure. Thyroid hormones are crucial for normal development and growth in children.

The good news is that perchlorates in breast milk don't seem to impact thyroid function in babies. Researchers have found thyroid gland problems in newborn animals. But the researchers found different results when it comes to human infants.

Federal Government Standards for Perchlorate

As discussed briefly above, the EPA is working on new laws regulating perchlorate in drinking water. The goal is to reduce risks to human health. Early initiatives set a preliminary clean-up goal of 24.5 ppb for perchlorate in water.

Massachusetts was the first state to set drinking water and waste site clean-up standards for perchlorate. Massachusetts set the standard at two ppb. It also requires most public water systems to test for perchlorate regularly.

What To Do if You Suspect Perchlorate Exposure

If you or a loved one experiences symptoms related to perchlorate exposure, seek immediate medical attention. You should call an experienced toxic torts attorney to discuss your legal options. Find a personal injury lawyer near you today.

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