December 11, 2024
You’ve probably heard about potential lead contamination in tumblers, drinking water, chocolate, packaged lunches, and even baby food. The cause for concern is justified: Lead is a potent neurotoxin, and there’s no safe level to ingest. The metal is particularly harmful to childhood development.
The good news is that in the United States, lead can no longer be added to many common products, and instances of lead poisoning among children have declined significantly over the past several decades.
Yet lead still persists on stuff we come into contact with every day, like old paint, dishes, and water pipes. Lead can also show up in food products and cosmetics via contamination, as well as in cheap imported goods from countries with fewer regulations.
Unfortunately, if you are curious or concerned about lead being in something you own, most home-testing options are limited. Tests—even those recognized by the Environmental Protection Agency—have been difficult to use, prone to user error, and expensive per test.
But what if an instant, easy-to-use, precise, and readily available test existed, one that allowed users to conduct literally hundreds of tests at a much lower cost than traditional methods?
I had this question until I came upon a method that produces a neon-green glow when the metal is present. (You also may have seen lead-safety influencers popping up on your social media feeds promoting different ways of testing at home.) One such method is Lumetallix, which is sold as a simple kit, comprising a spray or droplet bottle and a UV flashlight. Just spritz or drop some testing liquid onto a surface, and then pass a UV light over it. If the surface glows neon green, then the surface contains lead.
Before you start scanning your vintage glassware and chipping paint, however, there are a few important things to remember about this method; they will help you test strategically, to keep you and your loved ones safe.
DIY lead test results with little user error
The problem with testing for lead at home is that most tests on the market have a high cost per test, and they’re time-consuming and fiddly (requiring swabs, pipettes, or test tubes). They can also occasionally deliver inaccurate results, and they can’t detect lead at very low thresholds that may still pose a health risk.
For years, the most widely available EPA-recognized lead test was 3M’s LeadCheck—a tube that you crack to activate (sort of like a glow stick), rub onto the test surface, and watch for a color change to indicate the presence of lead. For EPA recognition, this test required a professional to administer it.
3M no longer manufactures this test, but cheaper versions are widely available on Amazon. They typically contain an orange-yellow swab of the same chemical, and they are known for being unreliable, as The New York Times reported during the Stanley tumbler scare in January 2024.
Although the neon-green testing method used by Lumetallix is not (yet) EPA-recognized, it purportedly produces no false positives because the solution reacts only with lead. This method can detect as little as a single nanogram of lead, making it significantly more sensitive than swab tests, according to Lumetallix.
The test’s signature glow is due to a compound called methylammonium bromide in the kit’s spray or droplet bottle. Wim Noorduin, a chemist at the Dutch research center AMOLF who helped develop Lumetallix, told me in a video interview that this colorless salt bonds with lead crystals, if they’re present, to form a kind of compound known as a perovskite. These perovskites, when exposed to UV light with the included flashlight, act as a semiconductor and glow green, indicating that lead is present.
According to Noorduin, these methylammonium bromide tests are 10 times more sensitive than the D-Lead two-part solution tests recognized by the EPA (though D-Lead tests can reliably detect regulated lead-based paint on wood, iron alloy, drywall, and plaster surfaces).
But the method still has limitations
Simple as they may seem, methylammonium bromide tests represent one of the biggest strides in lead detection in years.
However, there are limits to the method’s efficacy. Because of how these types of tests bond to lead, they don’t work on items with dissolved lead, like food, spices, or soil. They also can’t be used to test water (which is a common vehicle for lead).
To learn more about the potential impact of this method, I spoke with Andrew McCartor, executive director of Pure Earth—a nonprofit organization whose mission is to help reduce lead and mercury poisoning across the world—and with Angela Bernhardt, Pure Earth’s vice president of communications. (Pure Earth sells Lumetallix on its website, and it has worked with the company to test for lead abroad.)
Bernhardt pointed out that Lumetallix is simply a negative or positive test, and it doesn’t say anything about the volume of lead or the concentration; regardless of how much lead is present, a positive lead result glows with the same intensity.
The team at Pure Earth also isn’t sure whether Lumetallix is able to definitively assess the health risk of exposure, which is separate from the presence or absence of lead. For example, “If [a dish] was fired at a low temperature, the lead in the glaze is leachable with heat or acid,” McCartor said. But if that same dish is made with a lead-based glaze and fired at a high temperature, the lead might be fixed inside the glaze and not leech—posing no probable harm—though the item might still glow green when tested with a methylammonium bromide spray.
Nonetheless, Bernhardt said the test is a novel technology with an incredibly high ceiling. McCartor and Bernhardt told me that the organization has started using Lumetallix tests for its work in the field, but it is still figuring out Lumetallix’s limitations and best use cases.
It gives immediate, glow-in-the-dark results
This vintage sherry glass’s painted surface contains lead, according to our test with Lumetallix. Alex Aciman/NYT Wirecutter
An XRF test of the same sherry glass at Pure Earth’s office confirmed the Lumetallix results and detected 3,582 ppm of lead. Alex Aciman/NYT Wirecutter
Of course, we had to try out Lumetallix for ourselves.
It is every bit as simple as it sounds. After spraying the object with the enclosed colorless liquid, you pass the pocket-sized flashlight over the surface to get an instant result. And watching the green stain bloom in the presence of lead is a little spectacular. It is the perfect luminescent shade of Luke Skywalker’s Return-of-the-Jedi–Lightsaber green.
Just how prevalent would lead be in 2024? To find out, I first tried the Lumetallix lead test in my New York City apartment. I was certain that I would find danger lurking somewhere on some long-adored artifact, such as the harlequin-patterned serving plate I bought on my birthday one year or my collection of Waffle House Christmas mugs. And because I have a beloved cat who categorically refuses to drink from anything other than mugs, the thought that I might have exposed her to lead was, frankly, unbearable.
But when every dish and mug came up clear, I found myself almost disappointed that toxic dust had not reared its head.
The green glow finally appeared on a vintage sherry glass with a pheasant painted on it. I ran into the other room, where my wife was in the middle of a meeting, elatedly showing her what I had found.
I organized a “bring your vintage mug to work” day at Wirecutter’s office. Six coworkers brought in items, including children’s drinking glasses, vintage pint glasses from McDonald’s, a mid-century carafe, and assorted painted glassware. The telltale green glow consistently appeared on ornate, painted dishware and glasses, as well as on dishes made outside of the US.
The kit is easy to use—so easy, in fact, that while it would have taken me several days to test almost every surface in my apartment using literally hundreds of swab-style tests, with a methylammonium bromide test, it took only 15 minutes.
The UV flashlight has become the angel of death of beloved vintage mugs and dishes in my orbit. I’ve tested relatives’ heirloom dishware, and they were less than thrilled when I pointed out the risks of eating off of it.
A bowl with bright, hand-drawn colors found at my parents’ house. The same bowl under UV light, tested to show that the entire eating surface contains lead. Alex Aciman/NYT Wirecutter
With all of this green, I went to Pure Earth’s New York City headquarters to verify the test’s efficacy. There, my pheasant glass was subjected to an X-ray fluorescence (XRF) gun. This highly accurate, handheld piece of equipment effectively exposes materials to X-rays and can detect the precise makeup of an object in parts per million. My glass showed a highly elevated level of lead (3,582 ppm), confirming Lumetallix’s positive results.
Best practices for lead testing at home
Noorduin—who takes a spray test with him when he’s walking his dog so he can test surfaces around him—said he has detected lead on crystal glasses, PVC pipes, the leaves of plants near construction sites, electronic cables, window frames, plastic power-tool handles, vintage dishes, vintage metalware, and rubber workout equipment.
If you’re curious and want to take the additional step of testing what you already own at home, prepare to have your heart broken at least once. In my case, it was a cream-colored ceramic mug that was the perfect size for cappuccinos. For you, it may be a cup or plate you’ve had since childhood and hoped to pass on to your kids.
The EPA notes that lead may be found in some painted toys, furniture, and jewelry, as well as in some cosmetics, drinkware and dishware, and plumbing. And the CDC notes that products made in countries outside the United States may contain lead. (Luckily, while cheap drinkware and ceramics can contain lead, you probably don’t need to sweat new stuff from IKEA, which banned lead in its products in 2010.)
Some examples of household items that may contain lead
- mugs and glassware with any kind of design or lettering, especially if it’s raised
- vintage items that are painted
- colorful dishware, new or old
- brass items
- paint, paint chips, paint dust, window frames, and window sashes, especially in older homes or apartments
- appliance cables
- rubber grips on power tools
If a test detects lead in an object, keep the item out of reach of children, consider throwing it out, and immediately stop using it to eat or drink from.
If your child may have been exposed, quarantine the object in case further testing is needed, and speak with a pediatrician about next steps.
It’s also important to have a health provider routinely screen your kids for lead (some states, like New York, require lead testing for young children, when they are most vulnerable to serious developmental impacts).
If you find lead in surfaces or dust in your home, such as in paint or on a windowsill, don’t try to remove the source yourself. Instead, call your local government’s health department, or reach out to a lead-mitigation professional.
For any dishes or glasses that test negative, be sure to thoroughly wash off the testing liquid before using them to eat or drink from.
Thanks to the lead regulations of the past half-century, I detected no lead on almost all of the objects I tested. But that isn’t the case everywhere around the world or even around the US. And that’s why this testing technology is potentially empowering: The better our ability to quickly and easily test for lead in our homes, the closer we are to eliminating the risk.
This article was edited by Katie Okamoto and Catherine Kast.