A component of rocket fuel that has been linked to serious health issues shouldn’t be in your drinking water or food. Yet new tests by Consumer Reports have found that the chemical perchlorate—which is used in rocket fuel, missiles, explosives, airbags, and certain types of plastic—is in a wide variety of fast foods and grocery items. The highest perchlorate levels we found were in foods popular with babies and kids.
Our new findings come decades after perchlorate was first identified as a contaminant in water and food. Yet the problem remains largely neglected by the federal regulators tasked with keeping our food and water supply safe.
Perchlorate can get into the food we eat via water that has been polluted by improper perchlorate disposal, plastics that are made with the chemical and then used to store food, and bleach—which can break down into perchlorate—at food processing plants and water utilities. Experts think that for most people, food is the primary source of exposure.
Of course, you don’t want a component of rocket fuel in your fried chicken, rice bowl, or side salad. But it’s not just troubling in theory: Research suggests that people who are exposed to high levels of perchlorate may develop thyroid issues, including changes in hormone production. In adults, this may affect metabolism, potentially increasing the risk for metabolic disorders like type 2 diabetes.
And it can have an even greater impact on fetuses and young children because thyroid hormone levels can affect brain and nervous system development.
While none of the foods we tested had acutely dangerous levels of perchlorate, some did have enough that several servings of a food could add up to potentially hazardous levels. Plus, the presence of perchlorate in so many foods overall means that exposure over time is enough to be a cause for concern, especially for kids.
For years, environmental health scientists and advocates have implored regulators to set stricter limits on perchlorate in water and food. So far, action has been limited and hamstrung by multiple setbacks.
In 2019, the Food and Drug Administration denied a petition from a number of environmental advocacy and health groups that asked the agency to ban perchlorate in food packaging. In 2020, the Environmental Protection Agency walked back already delayed plans to set limits on perchlorate in drinking water. The agency was sued by the Natural Resources Defense Council (NRDC), and just last year, a U.S. Court of Appeals panel ruled that such a reversal was not allowed. The Court ordered the EPA to set limits on perchlorate; the agency now says it will propose those limits by Nov. 21, 2025. Experts say the ongoing lack of intervention from regulators is especially frustrating because there’s little consumers can do on their own to lower their exposure to chemicals that are so widely found in food and water.
In the meantime, here’s what we found and what it means for you.
What We Found
Scientists at Consumer Reports have long been concerned about perchlorate. These new tests were in part prompted by the ongoing lack of action from regulatory agencies, which has led to a gap in our understanding of just how pervasive perchlorate currently is in our food, says Tunde Akinleye, the CR chemist who oversaw our perchlorate testing. The last time the FDA evaluated perchlorate levels in food was more than a decade ago.
We looked at 196 samples of 63 supermarket products and 10 fast food items, chosen because previous scientific research suggests these foods may contain perchlorate. We also analyzed the type of packaging each food came in.
About 67 percent of the samples had measurable levels of perchlorate, at levels ranging from just over 2 parts per billion to 79 ppb. In general, baby/kid food, fast food, and fresh fruits and vegetables had the highest levels, with children’s foods averaging the highest average level, 19.4 ppb.
When looking at packaging types, foods in plastic containers had the highest levels (averaging nearly 54 ppb), followed by foods in plastic wrap and paperboard.
In 2005, the EPA established an “official reference dose,” essentially a safe exposure level, for perchlorate of 0.7 micrograms per kilogram of body weight per day. But many food safety experts think this level is not adequately protective and should be significantly lower, Akinleye says. The European Food Safety Authority has set a tolerable daily intake of less than half that amount: 0.3 micrograms per kilogram of body weight per day.
None of the foods we tested had perchlorate levels high enough for one serving to exceed the EFSA or EPA’s suggested daily limits. But we all eat more than a few servings of food per day, and children—because of their lower body weight—may be particularly at risk.
We found the highest perchlorate levels in certain fast foods and produce items, but concerningly, the category with the highest average level of perchlorate was baby and kid foods. Some of the baby and kid foods we tested that had the highest levels of perchlorate could quickly add up to a concerning amount. For a child between 1 and 2 years old, a serving of the boxed mac and cheese we tested would hit nearly 50 percent of the EFSA limit, and servings of the baby rice cereal, baby multigrain cereal, and organic yogurt we tested would each hit about a quarter of that limit. That means with one serving of each of the above foods—very possible over the course of a single day—a child would exceed the EFSA’s safe daily limit.
A serving—usually about three-quarters of a cup—of cucumbers, baby carrots, and collard greens would each exceed 50 percent of the EFSA daily limit for kids between ages 1 and 2 as well, making it easy for young kids to get relatively high levels of perchlorate each day, even from healthy food.
While our testing cannot reveal exactly why some foods had higher levels than others, some packaged goods like baby and kid foods may have higher levels because of anti-static plastic (which sometimes contains perchlorate), while fresh produce may contain perchlorate if it was irrigated with contaminated water.
We contacted several of the companies behind foods found to have high perchlorate levels in our tests, as well as some other major baby/kid food manufacturers, to ask if they were aware of perchlorate contamination and taking steps to minimize it in their products. None provided comments by publication time.
Regulators should do more to protect the public from contaminants like perchlorate, but at the same time, parents shouldn’t panic about what we found, says James E. Rogers, PhD, director of product safety testing at Consumer Reports.
While the perchlorate levels we detected could potentially add up to concerning levels for sensitive populations, the levels were not high enough to be immediately or acutely harmful. “Feeding your children a wide variety of healthy foods is the best way to make sure they get the nutrients they need and to minimize the potentially harmful effects of contaminants in food and water,” Rogers says.
How Perchlorate Gets Into Food and Water
Perchlorate occurs naturally in some parts of the world, but most people are likely exposed because of food and water that have been contaminated because of the industrial use of perchlorate, says R. Thomas Zoeller, PhD, a professor emeritus of biology at the University of Massachusetts Amherst.
Most drinking water contamination comes from activities related to the manufacture, disposal, and research of propellants, explosives, and pyrotechnics, as well as to accidental releases from manufacturing facilities and rocket launch failures, according to the National Institutes of Health’s Agency for Toxic Substances and Disease Registry. There are other sources of contamination, too, according to the ATSDR, including fireworks, road safety flares, and certain fertilizers. When crops are irrigated with contaminated water, that leads to contaminated produce.
A certain amount of perchlorate is also allowed in food-contact materials for dry foods, and the chemical is added to plastic as an anti-static agent. This prevents foods from clinging to the sides of plastic bags or containers, though there are other ways to reduce static buildup, says Tom Neltner, a chemical engineer and attorney who is the national director for the nonprofit group Unleaded Kids. As foods are moved from one plastic container to another, it’s likely they pick up some contamination from the plastic they touch, Neltner says.
Finally, bleach that has been sitting around for too long can break down into perchlorate. When old bleach supplies are used to clean food processing facilities or to treat drinking water, this may also lead to contamination, says Erik Olson, senior strategic director for health at the NRDC.
Potential Health Risks
Perchlorate can disrupt the thyroid by interfering with the gland’s ability to absorb iodine, an essential nutrient that is required for thyroid hormone production.
In adults, this may affect metabolism, and high levels of perchlorate exposure could potentially cause hypothyroidism or related issues. But—as is the case with many contaminants—perchlorate exposure is of greater concern for young children and pregnant people. That’s because thyroid hormones are critical for brain growth and development, and any disruption to that has the potential for lifelong effects.
Assessing the exact level where perchlorate exposure causes problems is complex, Zoeller says, because that level will vary based on a person’s baseline thyroid function and iodine intake. For a person with adequate iodine intake, it would take more perchlorate to cause problems, Zoeller explains. But iodine deficiency is more and more common as iodine intake has decreased in the U.S. since the 1970s, according to a 2019 review of research. Almost 25 percent of pregnant women in the U.S. don’t get adequate iodine, according to a 2020 study.
And while direct impacts are hard to document, there is research showing that when women with thyroid dysfunction have been exposed to higher levels of perchlorate during pregnancy, their children are three times as likely to show negative cognitive effects (including lower IQs) than children born to women exposed to relatively low levels.
Decades of Inaction
This isn’t a new problem. In 1985, some of the first large-scale perchlorate contamination was identified in wells near California Superfund sites (areas the EPA considers highly contaminated and a priority for cleanup), according to a report by the National Academies of Sciences, Engineering, and Medicine. In general, groundwater contamination was in large part due to military-industrial uses of perchlorate, via Department of Defense testing of explosives, munitions, and missiles, for example, as well as rocket tests and rocket fuel production.
But the extent of the contamination wasn’t clear until 1997, when new testing protocols made it possible for the EPA to test for perchlorate down to approximately 4 parts per billion, Zoeller says. The development of those testing protocols prompted the agency to do a risk assessment to see how many people were drinking water contaminated with the chemical. “They didn’t realize the degree to which mainly DOD had contaminated the planet,” he says. That’s when the EPA started requiring large public water systems to test for perchlorate.
In 2003, the Environmental Working Group tested lettuce for perchlorate and found it in nearly 20 percent of supermarket samples tested, often at high levels. Some of this was likely due to the contamination of Lake Mead, which led to perchlorate traveling down the Colorado River to Imperial Valley, Calif., where many of the leafy greens in the country come from, Olson says. Since 2003, a government cleanup has reduced much of that contamination. It’s also possible that the use of nitrate fertilizers from Chile, which are naturally high in perchlorate, played a limited role, though only in sites where these fertilizers were used, he says.
In 2005, in the midst of emerging controversy about perchlorate contamination affecting water and crops, the FDA granted companies permission to include perchlorate in food-contact materials. Neltner says that it was only years later that health advocates realized the agency had made this surprising decision.
As part of the FDA’s regular evaluation of foods for contaminants, the agency tested a number of foods for perchlorate from 2005 to 2006 and from 2008 to 2012. When analyzing that data, advocates realized that after the 2005 decision, there had been a dramatic increase in perchlorate levels in certain baby foods that were allowed to be stored in perchlorate-containing packaging. “It went from virtually no detection in baby food cereals to really high levels,” Neltner says. “FDA has never explained the change, but the use in plastic is the obvious suspect.”
There was a hope that the FDA would at that point stop letting companies use perchlorate in certain food packaging and handling equipment, Akinleye says. “It was not difficult to attribute that spike of exposure in very young children to the use of perchlorate in packaging,” he says. But the FDA decided not to make any changes. The agency justified its decision in its denial of the petition from the NRDC and other groups. (The FDA did not provide further comment on this decision by publication time.)
By 2011, the EPA concluded that between 5.2 and 16.6 million people in the U.S. could be potentially exposed to concerning levels of perchlorate in drinking water. Some experts think the number would be even higher if the EPA had used a stricter limit—like that set by certain states.
What Regulators Could Do
With so little action from regulators so far, CR’s experts say there’s much that the FDA and EPA could do to improve the situation, especially because there’s little consumers can do to avoid the chemical. Those with particularly contaminated water supplies could install reverse-osmosis filtration systems, which the EPA says can effectively filter out perchlorate, but that doesn’t help people avoid exposure from food. In general, getting enough iodine can offset the potential harms of perchlorate, so be sure you’re getting enough of that essential nutrient.
To reduce perchlorate levels in foods—baby foods in particular—the FDA should revoke the permission to use perchlorate in food contact materials, Neltner says. And Akinleye, at CR, says the FDA could set a limit for perchlorate in food that takes into account the unique risks young children face from exposure and would allow the agency to remove products from the market that exceed that limit.
The EPA has already issued guidance advising water utilities not to store bleach for too long, which has helped, Akinleye says. These management practices should be extended to all food processing facilities as well.
Regulators should review the safe daily intake level that they’ve used when starting to discuss limits, Akinleye says. While the EPA does not yet have guidance or limits on perchlorate in drinking water, the agency does have what it considers an oral reference dose for daily consumption of the chemical—a sort of safe guideline that may be used to set future limits. But this dose is more than double the European level, which is significantly more protective based on what we know so far, Akinleye says. Some states have taken such action on their own. When setting state limits for perchlorate in drinking water, Massachusetts, for example, used a safe daily intake level that’s one-tenth the level of the EPA’s reference dose.
To reduce perchlorate in drinking water and produce, the EPA needs to follow up on its long overdue commitment to set maximum contaminant levels for perchlorate in water, Olson says. Ideally, the agency would follow the lead of states like Massachusetts and California in setting a limit, he says: The Massachusetts limit is 2 ppb, and the California limit is 6 ppb—though the state has set a goal of reducing that to 1 ppb. When the EPA does propose limits, which the agency has said it will do by 2025, setting strict limits like this could drive cleanup activities in contaminated areas.
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