Minnesota now has the nation’s most far-reaching ban on toxic “forever chemicals” in consumer products, so dental floss, children’s clothing, makeup and many other items you find on store shelves should be safe from PFAS.

Since those chemicals don’t usually show up on ingredient lists, shoppers have to take it on faith that retailers and manufacturers are heeding the ban.

The toddler-sized raincoat is cut up for testing.

The Minnesota Star Tribune didn’t want to do that. So we asked the state agency that enforces the ban how it would test products to find out whether PFAS have been added. Then we went shopping.

As of Jan. 1, retailers were not allowed to sell products with PFAS in 11 specific categories, whether or not they were already sitting on store shelves. A day after the ban took effect, on Jan. 2, reporters bought 20 items from local retailers. We took those products to a laboratory, where parts were incinerated to test for total organic fluorine, the screening method the state uses.

Sixteen of the products, including toys and tampons, tested well below a key fluorine limit, meaning they effectively meet the state’s standard. Four of them, including two makeup products, were above the threshold.

One product, a frying pan, disclosed on its label that it contains PFAS, so it should not have been on the shelf at Fleet Farm. For the other three items above the state’s screening level, the results don’t prove those products contain illegal levels of PFAS. But the levels are high enough that the state would seek further testing to pinpoint what’s triggering those results.

“We’ve got more work to do,” said Kirk Koudelka, assistant commissioner at the Minnesota Pollution Control Agency (MPCA). “This isn’t going to feel like a switch flipping, but it’s encouraging.”

The ban applies to tens of thousands of individual items across 11 categories, including cookware, menstrual products and cosmetics. The law doesn’t allow companies to sell through existing stockpiles of consumer products. But for now, the MPCA is focused on educating manufacturers and retailers rather than punishing them.

“We’re still getting a lot of questions,” Koudelka said. “There are a lot of folks last-minute realizing that this applies to them.”

Many experts said the test results were promising, since just a few years ago the prevalence of PFAS was much higher in the types of products tested, including dental floss, clothing and waterproofing sprays.

Still, others who reviewed the results were alarmed by the amount of “background” fluorine picked up by the tests. The PFAS family of chemicals, perfluoroalkyl and polyfluoroalkyl substances, don’t break down in the environment, and they build up in the bodies of people who consume them.

Chronic exposure to some PFAS over the long term is linked with cancer and other illnesses, according to an influential 2022 review of the science from the National Academies of Sciences, Engineering and Medicine. Minnesota’s ban is named Amara’s Law after a young woman, Amara Strande, who grew up drinking PFAS-tainted water and later died of a rare cancer.

Minnesota’s law only addresses intentionally added PFAS, not chemicals that may have accidentally contaminated a product. State regulators have an unofficial threshold of 100 parts per million total organic fluorine, based on California regulations and scientific studies, that denotes “intentionally added.”

“Consumers have the right to know what they’re buying and what they’re exposing their kids to, and what they’re putting on their body,” said Avonna Starck, state director for Clean Water Action. “It makes me realize how much work we have to do.”

Cally Edgren, a product compliance expert and vice president of regulatory and sustainability at supply chain company Assent, said the results are “eye-opening” and should help consumers connect the prevalence of PFAS to their personal lives.

“One takeaway is you can’t rely on the law yet to keep PFAS out of your life,” she said. “But whether or not it takes a while to get things off the shelf, and I think it will take a while, Minnesota has advanced the story significantly with this law.”

Because of Minnesota’s definition of PFAS — “chemicals containing at least one fully fluorinated carbon atom” — the state uses a broad test to screen for PFAS: total organic fluorine.

A stick of Maybelline Lash Sensational mascara and a bottle of L’Oréal Infallible 24-hour foundation, both purchased at a Brooklyn Park Walmart on Jan. 2, each had total organic fluorine levels well above the state’s threshold, indicating they may contain PFAS.

There is no certainty which chemicals are present without additional tests — and there are hundreds of PFAS in commercial use.

However, given the amount of fluorine in the mascara and foundation, scientists who track the chemicals in products and attorneys who work with industry said the manufacturer should know what ingredients would cause such a test result.

When presented with the lab results and a series of questions, a L’Oréal spokesperson said: “Product safety is L’Oréal’s top priority. All our products undergo rigorous testing for quality, safety and efficacy before reaching consumers.” The French cosmetics conglomerate owns the brands of all but one of the makeup products the Star Tribune tested, including Maybelline.

L’Oréal’s website states that although it sought to remove PFAS from its formulas by the end of 2024, “older references may still be found on the market until retailer stocks are exhausted.”

Walmart did not respond to requests for comment about the tested products. State law says products subject to the PFAS ban cannot be offered for sale in Minnesota as of Jan. 1.

Cosmetics have long used PFAS because they have strong waterproofing properties, helping products form a cohesive film across the skin, and preserve other ingredients.

But labels seldom indicate clearly that the chemicals are there.

In 2021, Notre Dame researcher Graham Peaslee screened more than 200 cosmetics sold in North America for fluorine. According to the testing, 52% of the products had high levels of fluorine.

Peaslee’s group then conducted additional tests to find specific PFAS in 29 makeup products. Every one of them contained at least a handful of different PFAS — but only 3% of them listed ingredients that indicated the chemicals were there.

In the case of the two cosmetics that showed higher organic fluorine levels in the Star Tribune’s tests, only the foundation listed an ingredient on the label that left a clue that fluorine was there: “synthetic fluorphlogopite,” which Peaslee said was probably a mica — a mineral dust used in cosmetics — that has been fluorinated to preserve its shiny nature.

That ingredient may not fall under Minnesota’s definition of a PFAS, however, and L’Oréal did not answer questions about it.

The regulation of chemical ingredients in makeup is historically lax, and many times, lawsuits are the driving force to remove dangerous materials from formulas, Peaslee said. There are no federal regulations limiting PFAS in cosmetics, though the Food and Drug Administration published a list of PFAS ingredients in 2023. None were listed on the labels of products purchased by the Star Tribune.

Edgren, the supply chain compliance expert, said she wasn’t surprised that waterproof makeup tested high in fluorine.

“This isn’t the first time cosmetics have been tested,” she said, “but it is the first time it’s been illegal for them to be selling that.”

At the Fleet Farm in Oakdale just off Interstate 694, a row of pots and pans featured various claims about being free of certain chemicals or coatings.

One pan in particular, from KitchenAid, disclosed on the packaging that it contains PFAS.

Test results confirmed as much. Fluorine levels were so high they could only be estimated at greater than 10,000 parts per million — at least a hundred times the state’s threshold.

Meyer Corp., which manufactures KitchenAid cookware, wrote in a statement the company is “committed to complying with all regulatory obligations, including Minnesota’s recent prohibition on intentionally added PFAS in cookware.”

The company told distributors and sales representatives to keep fluoropolymer-coated cookware off Minnesota retail shelves as of the start of the year.

“We are happy to confirm that, since the law went into effect on Jan. 1, Meyer has not manufactured, distributed or sold any products with intentionally added PFAS to distributors in Minnesota,” Meyer wrote in the statement.

Fleet Farm was provided with the test results and a list of questions but did not respond to requests for comment.

Cookware is a well-known source of PFAS in consumer products because it was one of the first commercial uses of the family of chemicals. Teflon, or PTFE, has been used on nonstick pans in the U.S. since 1961, and it is not going down without a fight.

The Cookware Sustainability Alliance sued Minnesota in January, calling Amara’s Law unconstitutional. The group, which represents major cookware companies, also said PTFE “has been repeatedly validated as safe for food contact by the FDA and other regulatory bodies.”

Teflon no longer uses PFOA, a type of PFAS the EPA says is likely to cause cancer, as an ingredient. But Peaslee said his research still found trace amounts of PFOA and other PFAS in Teflon products, and multiple studies have found that making Teflon can pollute the environment.

Unless a federal judge says otherwise or legislators revise the law, PTFE counts as a PFAS chemical and cannot be intentionally added to cookware or many other products in Minnesota.

Meyer and other consumer product companies have taken issue with using a total organic fluorine test as a proxy for PFAS.

Fluorine tests “report the presence of many other compounds in addition to PFAS, so they are not a direct measure of the chemistry,” Meyer said in a statement.

Still, laboratories, regulators and third-party certification firms told the Star Tribune they rely on fluorine tests as an initial screen. High levels of organic fluorine are highly correlated with the presence of PFAS and can help determine which items are worth testing for specific PFAS chemicals, said Ben Mead, managing director of Hohenstein Americas, an Indiana-based product testing laboratory.

“Our advice to companies is to do what you did: Use the total organic fluorine test, because you don’t care what substance is there, you want them all gone,” Mead said. “If you don’t have fluorine, then you have a pretty good sense you’re going to be compliant.”

Even when certifying a product as PFAS-free, Mead said his lab finds traces of fluorine, similar to the low readings found in most of the Star Tribune’s test results.

The total organic fluorine standard is especially challenging for a pair of N’Ice Caps gloves sold by the Oakdale Fleet Farm on Jan. 2.

The waterproof exterior of the children’s gloves had a total organic fluorine reading of 188.8 parts per million, nearly twice the state’s threshold. The Minnesota-based company said supplier testing showed the fluorine is from a non-hazardous chemical and not a PFAS.

“We believe these products do not contain PFAS,” N’Ice Caps co-owner Joe Fahndrich wrote in an email. “Nonetheless, we have also provided your testing results to our suppliers to ensure compliance.”

Said N’Ice Caps co-owner Curtis Fahndrich, Joe’s brother: “We are aware this substance contains [fluorine] atoms, but again, we do not believe the particular compound used would be of concern.”

“Our own children wear these products,” he said, “and we would never knowingly expose them to toxic compounds.”

State regulators will eventually start combing aisles and buying products for their own compliance “spot checks.”

The MPCA will rely on the same test the Star Tribune used for an initial screening. When fluorine levels come back high, the agency may test for individual PFAS.

The staff and budget are in place, but there isn’t a timeline to start testing. The MPCA is still finalizing the details of how it will enforce Amara’s Law.

When PFAS are found, regulators want companies to answer one question: What are you going to do about it?

In January, the Minnesota Star Tribune hired a local laboratory to test 20 items to check whether retailers and brands were ready for a nation-leading crackdown on “forever chemicals.”

As of Jan. 1, Minnesota no longer allows intentionally added PFAS in 11 product categories: carpets and rugs; cleaning products; cookware; cosmetics; dental floss; fabric treatments; juvenile products; menstruation products; textile furnishings; ski wax; and upholstered furniture.

The items we tested were chosen for exposure potential and body contact. So instead of ski wax and furniture, we opted for makeup and children’s products.

All products were purchased on Jan. 2, at large stores available to most Minnesotans.

Novem Scientific in Cottage Grove sampled a small portion of each item for total organic fluorine, the state’s preferred screen for the presence of PFAS. In most cases, we tested parts of products closest to the body — like the lining of a maxi pad. No packaging was tested.

We shared the test results with every product manufacturer and retailer, and invited them to comment.

A total organic fluorine test does not show which chemicals are present, so these results don’t show whether the most toxic forever chemicals were used, like PFOS and PFOA. But it’s a first step to indicate where PFAS may be lingering.

Minnesota regulators have a benchmark of 100 parts per million (ppm) total organic fluorine, borrowing from published research and a California law. Above that level, a PFAS chemical was likely intentionally added and a manufacturer should be aware of its presence. State regulators said this threshold would trigger an inquiry for the manufacturer.

We asked experts about the exposure risks for products that are applied to the body, like foundation, or that sit next to intimate areas, like a diaper. Research on how PFAS absorb through the skin is still developing, and experts agreed the risk isn’t as high as eating or drinking the chemicals. But that doesn’t mean it’s zero.

On the rack in the Edina Target, the toddler-sized raincoat seemed like the perfect product to test for PFAS.

The light magenta jacket was waterproof, a classic use of the “forever chemicals” that repel water and grease. It was made for kids — the type of product where PFAS, or perfluoroalkyl and polyfluoroalkyl substances, are now banned in Minnesota.

But in the lab of Novem Scientific in Cottage Grove, things got complicated.

Andrew Christianson, Novem’s founder, plucked at different pieces of the coat — the lining of a sleeve, a reflective band, the fabric behind the neck, the shell. All could be different materials, made with different chemicals.

What, exactly, did we want to test?

And what would the state of Minnesota test to enforce a nation-leading law banning “forever chemicals”?

The state told us it’s still working on that question.

“You’ve kind of hit some of the parts that we have to work out as we build in our compliance and enforcement strategies,” said Kirk Koudelka, an assistant commissioner at the Minnesota Pollution Control Agency (MPCA). “How do we do this consistently?”

There are few examples to look at. The EPA offers no method for testing so many different products. Nonprofit standards group ASTM is still working on its own recommendation.

The Minnesota Star Tribune contacted the MPCA in October to learn about how the state would test consumer products subject to the Jan. 1 PFAS ban. Our goal was to probe whether retailers and manufacturers were ready, using the same methods as regulators.

State officials said they would first look for total organic fluorine. This test measures all the fluorine-carbon bonds inside a product.

These bonds, some of the strongest in chemistry, have made thousands of PFAS durable and useful. But they’re also the source of the nickname “forever chemicals” — in nature, they don’t break apart.

So the Star Tribune hired Novem to run total organic fluorine tests on 20 items. We purchased them at four metro area retailers on Jan. 2. The results wouldn’t definitively prove the presence of PFAS — but they signal where they might be hiding.

Novem shaved small samples off each product we delivered, including a tampon and a Winnie the Pooh crib toy. We sampled components likely to end up on or inside the body, like the teething ring attached to Winnie.

For the raincoat, made by Target’s in-house brand Cat & Jack, the lab took a half-and-half sample of the waterproof shell and fabric lining of a sleeve.

We wanted to measure the potential that PFAS was touching the skin on the inside, and possible PFAS in the waterproof layer.

Reporters and a photographer observed a test on a bitterly cold day in January, but the small blue room filled with analytical machines heated up quickly. That’s because samples must be burned at over 1,900 degrees Fahrenheit to tear apart the carbon-fluorine bond.

The full process required a two-part test.

First, Christianson burned apart the bonds and measured all the fluorine left behind.

Then, a second sample of the product was shaken in water. This captured all the fluoride that might be floating around alone or in the form added to drinking water to make teeth stronger. That water was then measured for fluorine with an electrode.

Taking the second result and subtracting it from the first would give us the answer we sought. How much fluorine was locked with carbon in a near-unbreakable bond?

We observed the first part of this test, which started as Christianson snipped fragments of the coat from a sleeve.

The pale magenta scraps were placed in a small white plastic dish, and then inside a clear plastic box. Inside that box, a robotic arm picked up the dish and shuttled it into a closed metal chamber, where the incineration began.

From there, gases from the burn were trapped, collected into a liquid, then bubbled upward through a clear tube into a tan cylinder. Inside, the atoms separated into groups, with all the fluorines clustered together.

At the end of the chain of machines, a computer monitor showed the measurements coming out in real time as a line slowly crawled across a chart. After a few seconds, it spiked, indicating the fluorines had been released.

Total organic fluorine is the state’s preferred first test because there are so many different forms of PFAS. Hundreds of the chemicals are in use commercially, and those chemicals can break down into other PFAS.

But the method has weaknesses. In rare cases, it can accidentally pick up fluorine bonded to calcium, which is not a PFAS under any definition. And the test has a mixed record in court.

Brian Gross, an attorney and partner with the national law firm MG+M, said most courts have concluded total organic fluorine doesn’t prove PFAS is in a product.

These cases involve consumers suing companies over their products. No court case has directly tested a state regulation that relies on total organic fluorine, Gross said.

The MPCA also said it would not rely on a total organic fluorine test alone if it were pursuing an enforcement case.

Still, determining exactly which PFAS might be in a product with additional tests is devilishly difficult.

An EPA-approved test for water, fish tissue and sewage sludge can only detect 40 types of the chemicals.

Sometimes, a company tests a product and gets a high fluorine result, said Nick Nigro, who works at the national commercial testing laboratory Pace Analytical. Then, they want to find exactly what PFAS might be there, but using the EPA method turns up nothing.

Christianson said he’s had similar situations with other clients.

“[That’s] the last place you want to find yourself in science, is trying to figure out what the heck is in there” that other tests can’t find, he said.

The little pink jacket, returned to the newsroom, had matching sleeves — each with a 6-square-inch chunk missing at the cuff.

The tests now complete, we turned to state officials to help us understand how much fluorine was too much. They told us that if they had conducted the testing, any result above 100 parts per million would trigger an investigation.

The threshold is not part of Minnesota’s law banning PFAS, or any formal rule. The state is using it as a guidepost in part because the level is written into California’s more limited ban, MPCA officials said.

In California, the threshold originated in the composting industry, because it was a level that could be reliably tested in paper packaging, according to Anna Reade, a senior scientist at the Natural Resources Defense Council. Several experts said the level is a reasonable proxy for “intentionally added” PFAS, the actual language in Minnesota’s law.

Below that level, there usually isn’t enough PFAS to make a product waterproof, stain-resistant or nonstick. But Reade added that there are still unknowns about how PFAS are used in each situation — so for some items, a lower level may eventually be necessary to detect PFAS that manufacturers are adding.

In all, only four items the Star Tribune bought tested above 100 parts per million.

A KitchenAid-branded pan disclosed on the label that it used PTFE, a type of PFAS with many fluorines attached. Its test produced a result so high the number was better represented as an estimate, Christianson said. A waterproofing shoe spray and a rug scored the lowest, clocking in below the limit of detection.

And the pink raincoat, we learned, was well below the level of concern — at just 4.9 parts per million.

At the beginning of testing, we thought about all the ways the products we picked might expose people to PFAS. One reporter recalled his small children wiping their runny noses with the edge of their coat sleeves.

Now we knew: For this particular jacket, there was no real risk.