Some anti-5G pendants were radioactive, and EMF research has evidence on both sides

Key takeaways

• In December 2021, Dutch nuclear regulators told people to stop wearing 10 “anti-5G” and “negative ion” products, including a child’s bracelet, because they gave off ionizing radiation.
• A 2024 review commissioned by the World Health Organization pooled 63 studies and found, with moderate certainty, that mobile phone use likely doesn’t raise the risk of brain tumors.
• People who feel sick around electronics have real symptoms, but in blinded tests they can’t tell a real signal from a fake one better than chance.
• The Federal Trade Commission sued sellers of phone “radiation shield” patches in 2002, and the FDA says shielding products generally don’t work as advertised.
• Strong, focused magnetic pulses do work in medicine: the FDA has cleared magnetic brain stimulation for depression since 2008, while static magnets show no conclusive benefit for pain.

In December 2021, the Dutch nuclear safety regulator, known as ANVS, issued an unusual warning about jewelry and other wellness items¹.

Ten products sold to guard against 5G and other radiation, or to deliver “negative ions,” turned out to be radioactive themselves¹². The list included pendants, bracelets, a sleep mask and a children’s bracelet with a smiley face¹².

The regulator told owners to stop wearing them and to store them in a closed cabinet². It told them not to throw the items in the trash, because they contained radioactive material². Wearing one around the clock for a year could push skin exposure past the Dutch limit².

Selling them was illegal in the Netherlands. But the regulator couldn’t act against sellers abroad, and some items were still listed online days later².

There’s a hard irony here. The products promised protection from phone and Wi-Fi signals, which lack the energy to damage DNA. Instead, they gave off ionizing radiation, the kind that can²³.

The same aisle often sells the opposite promise: magnets, PEMF (pulsed electromagnetic field) mats and grounding sheets that claim to heal. Both pitches rest on one idea, that weak everyday fields have strong effects on the body. Researchers have tested that idea from both directions.

Phone signals and X-rays are both radiation, but only one can break DNA

“Radiation” covers two very different things. Ionizing radiation, such as X-rays, radon and cosmic rays, carries enough energy to damage DNA, which can raise cancer risk³.

Phones, Wi-Fi and cell towers use radiofrequency (RF) energy, which is nonionizing. The National Cancer Institute (NCI) says it is too weak to damage DNA³. The only effect consistently seen in people is slight heating of the area where a phone is held, not enough to raise body temperature in a measurable way³.

Older 2G to 4G phones use frequencies of about 0.7 to 2.7 gigahertz. 5G is expected to reach as high as 80 gigahertz³. That’s higher, but it is still radiofrequency energy, on the nonionizing side of the line³.

“Possibly carcinogenic” was a cautious label, and newer reviews are reassuring

In 2011, the International Agency for Research on Cancer (IARC), part of the World Health Organization, classified RF fields as “possibly carcinogenic to humans”³. It based that label on limited evidence in people, limited evidence in rodents and inconsistent lab findings³. In plain terms, the evidence was too thin to rule harm in or out.

Much more data has come in since:

• Interphone, a study in 13 countries, found no overall rise in brain tumors. A small rise in one tumor type among the heaviest callers was judged inconclusive³.
• A Danish study of more than 358,000 phone subscribers found no link to brain tumors, even after 13 years or more³.
• The COSMOS study of 264,574 people found no link, including among the heaviest users³.
• U.S. cancer statistics show that rates of glioma in adults have held steady for decades³.

Animal studies are murkier. The National Toxicology Program exposed rats and mice to RF over their whole bodies at three strengths, the highest being 9 watts per kilogram³. Some male rats developed a type of heart tumor called a schwannoma, while female rats and mice overall did not³. The International Commission on Non-Ionizing Radiation Protection (ICNIRP) found major weaknesses in that study and a similar one by Italy’s Ramazzini Institute³.

In September 2024, a review commissioned by the WHO pulled the human evidence together⁴. Led by Ken Karipidis of Australia’s radiation safety agency, ARPANSA, the team pooled 63 studies from 22 countries published from 1994 to 2022⁴⁵.

Mobile phone use wasn’t linked to glioma, meningioma, acoustic nerve tumors, pituitary or salivary gland tumors, or childhood brain tumors⁴. Risk didn’t rise with years of use, total call time or number of calls⁴. The authors rated their confidence as moderate⁴. They also found, with moderate certainty, that living near cell towers and broadcast antennas likely doesn’t raise childhood leukemia risk⁴.

A second WHO-commissioned review, published in early 2025, looked at leukemia, lymphoma, thyroid and oral cancers in 26 studies⁵. It also found no link, though with less certainty, since these cancers have been studied less⁵. The WHO is preparing an updated assessment of RF health effects that will draw on this series⁵.

Shields and stickers: the FTC sued, and the FDA says they don’t work

In February 2002, the FTC sued two companies that sold patches meant to stick over a phone’s earpiece⁷. Their ads claimed the patches blocked up to 97% or 99% of radiation⁷.

Most of a phone’s electromagnetic energy comes from the antenna and other parts of the phone, not the earpiece⁷. Tests by the Good Housekeeping Institute, which referred the cases, found the patches didn’t reduce exposure⁷.

“There is no scientific evidence that their products work as they claim,” said J. Howard Beales III, then head of the FTC’s Bureau of Consumer Protection⁷.

In 2003, one seller settled. A court order barred it from claiming any product reduces radiation unless reliable science backs the claim⁸.

The FDA’s current advice is similar. It doesn’t regulate these accessories, considers their claims unsupported, and says shielding products generally don’t work as advertised⁶. They may also interfere with the phone, and at worst could keep it from finding a signal when you need to call for help⁶.

If you’d like to lower your exposure anyway, the free steps work better than any sticker³⁶:

• Use speaker mode, a headset or earbuds to keep the phone away from your head.
• Keep calls shorter, or text instead (never while driving).
• Avoid long calls when the signal is weak, because phones transmit harder then.

The FDA says there’s no proven health benefit from cutting RF exposure, so treat these steps as a free choice, not a medical need⁶.

When people feel sick around electronics, the symptoms are real

Some people say Wi-Fi, phones or power lines make them ill. The symptoms most often reported are headaches, poor sleep, trouble concentrating, fatigue and ringing in the ears, and many people say they react within minutes¹⁰.

This isn’t rare. Surveys have put the share of people who describe themselves as sensitive anywhere from 1.5% (Sweden, 1997) to roughly one in 10 (Germany, 2004) and 13% (Taiwan, 2007)¹⁰. For most, daily life goes on; a much smaller group is badly disabled by it¹⁰.

Australia’s radiation safety agency says these symptoms are real and can be disabling⁹. Researchers often call the condition IEI-EMF, short for idiopathic environmental intolerance attributed to electromagnetic fields¹⁰. “Idiopathic” means the cause isn’t known.

The best way to test whether the fields cause the symptoms is a provocation study. Volunteers are exposed to a real field or a sham one, and neither they nor the researchers know which is which¹⁰.

In a 2025 overview, researchers Frank de Vocht and Martin Röösli pointed to a recent review of 40 such studies¹⁰. Under blinded conditions, people with IEI-EMF couldn’t tell when a field was on better than chance, and their symptoms didn’t differ from those of comparison groups¹⁰. Australia’s radiation agency reports the same finding from a 2024 review commissioned by the WHO⁹.

What does seem to matter is expectation. In open tests, where people know they’re exposed, symptoms appear¹⁰. In some experiments, people reported symptoms after being told, falsely, that a field was on¹⁰. Scientists call this a nocebo effect, and it isn’t imagined or faked: expecting harm can produce real physical symptoms.

A 2025 study in the journal Bioelectromagnetics tested people who report sensitivity, using a protocol designed together with them¹¹. Of 16 people who finished all 12 sessions, none could reliably tell real exposure from sham¹¹. Symptoms didn’t differ between the two. But symptoms rose when people believed they had been exposed, a pattern that was clear in 8 of the 16¹¹.

These studies have limits. They test short exposures, not years of living with a signal¹⁰. The WHO also notes that noise, other environmental factors, or worry about new technology may play a role in people’s symptoms¹².

Researchers’ roles matter here too. In the 2025 overview’s acknowledgments, de Vocht discloses that he sits on ICNIRP and consults occasionally for the Electric Power Research Institute, though the paper’s formal conflict statement lists none¹⁰.

Help exists. Cognitive behavioral therapy, a structured talk therapy, has helped some anxious patients whose daily lives were disrupted¹⁰. A Swiss counseling project concluded that care should focus on the person’s condition, whatever they believe the cause to be¹⁰. ARPANSA advises affected people to see a qualified medical specialist⁹.

Where electromagnetic medicine works: strong, focused and prescribed

Electromagnetic fields can change the body when they’re strong, aimed and used for a defined condition.

The clearest example is repetitive transcranial magnetic stimulation, or TMS. A coil held against the head sends short magnetic pulses that create small electric currents in brain cells¹³. The FDA first cleared it in 2008 for depression in people who hadn’t improved on at least one antidepressant¹³.

A standard course runs five days a week for four to six weeks¹³. The National Institute of Mental Health says strong clinical evidence supports TMS for easing depression, though it doesn’t match electroconvulsive therapy¹³. Common side effects include scalp discomfort and mild headaches, and the risk of seizure is low¹³. Clearances have since expanded to obsessive-compulsive disorder in 2018, migraine, smoking cessation and, in 2024, add-on treatment of depression in teens 15 and older¹³.

The FDA has also approved PEMF devices for certain bone fractures that fail to heal and for pain and swelling after surgery¹⁴. These are prescription treatments chosen by a clinician for a specific problem.

Magnets, PEMF mats and grounding: weak fields, weak evidence

Static magnets. These are the magnets in bracelets, insoles and wraps. A 2021 review of seven studies with 576 people found mixed results¹⁴. The National Center for Complementary and Integrative Health (NCCIH) says no conclusive evidence shows that static magnets work for any kind of pain¹⁴.

PEMF for pain. A 2020 review of 21 studies with 1,101 people found less pain and better function in several muscle and joint conditions¹⁴. A 2022 review found benefit for chronic low back pain, but a review of shoulder pain studies found none, and NCCIH calls the overall data mixed¹⁴. A home mat may not match the devices tested, so ask the seller which study used its device.

Grounding, or earthing. Grounding products connect your body to the earth through a wire, mat or sheet. In a 2011 journal editorial, James Oschman summarized grounding studies that reported changes in blood minerals, thyroid hormones and blood sugar¹⁵. He also disclosed that this research, and his own writing on it, had been sponsored by the company that makes grounding products¹⁵.

Company funding doesn’t make a result wrong. It’s the same standard natural-health readers rightly apply to drug-company research: wait for independent teams to repeat the findings. We didn’t find large, independent trials of grounding.

A few safety notes from NCCIH apply to magnetic products¹⁴:

• Magnets may interfere with pacemakers and insulin pumps.
• Take magnetic devices off before an MRI.
• Swallowed magnets can be deadly, so keep small ones away from children.
• Don’t use magnets to put off seeing a clinician about pain.

The evidence at a glance

This table uses four levels: strong evidence, promising but early, not enough evidence, and evidence says no (or unsafe).

Claim	Evidence level	What the research shows
Phone use causes brain tumors	Evidence says no	63 studies, no link even with long or heavy use; moderate certainty4
Cell towers cause childhood leukemia	Evidence says no	No link in pooled studies; moderate certainty4
Phones cause leukemia, lymphoma or thyroid cancer	Evidence says no	No link in 26 studies, but lower certainty5
Phone shields and stickers cut exposure	Evidence says no	FTC cases and FDA advice: they don’t work as advertised67
Anti-5G pendants protect you	Evidence says no, or unsafe	Ten products sold in Europe were radioactive12
People can sense RF fields and get sick from them	Evidence says no	About 40 blinded studies: no better than chance; symptoms are real but tied to belief of exposure91011
TMS for depression	Strong evidence	FDA-cleared since 2008; strong clinical evidence13
PEMF for muscle and joint pain	Promising but early	Some benefit in reviews, none for shoulder pain; data mixed overall14
Static magnets for pain	Not enough evidence	Mixed results; no conclusive benefit for any pain14
Grounding for better health	Not enough evidence	Mostly company-sponsored research15

Precaution is a fair instinct. Spend it where it counts

Many natural-health readers prefer to reduce exposures they can’t see, and that instinct deserves respect. The good news is that the steps that lower phone exposure are free³⁶.

The NCI notes that the most consistent health risk tied to cell phones is distracted driving³. Putting the phone away in the car protects you more than any pendant.

Listening to your body matters too. Blinded tests take symptoms seriously by looking hard for the true cause, and they hold a shield to the same standard as a new drug.

How to report a problem. Report misleading EMF claims to the FTC at ReportFraud.ftc.gov. Report problems with a medical device to the FDA through MedWatch. If you think you own a radioactive product, don’t throw it in the household trash. Store it away from people and ask your state or local health department how to handle it.

Questions readers ask

The bottom line

The shelf of electromagnetic products makes two opposite promises, and the research backs neither one well. Large reviews find, with moderate certainty, that phones likely don’t raise brain tumor risk. People who feel sick around electronics have real symptoms, but they can’t detect the fields in blinded tests. Shields don’t work, and some “anti-5G” jewelry was itself radioactive.

On the healing side, focused medical devices such as TMS have solid evidence, while static magnets, home PEMF mats and grounding remain unproven. If you want less exposure, use the free steps. If you feel unwell, bring your symptoms to a clinician who takes them seriously, and keep any prescribed care in place.

Related reading

• “FDA registered” isn’t “FDA approved”: a buyer’s map to wellness devices
• Fear sells health products, and five questions show when the threat is real
• Who paid for the study matters, even when the science is real
• What to say when a doctor isn’t taking you seriously
• A magnet can pause a defibrillator, so check these device warnings first

Sources

1. D’Agostino S. “‘Anti-5G’ Jewelry and Sleep Masks Are Radioactive.” Bulletin of the Atomic Scientists, 2021. thebulletin.org
2. Euronews. “Radioactive Anti-5G Jewellery Banned in the Netherlands but Still on Offer Online.” Euronews, 2021. euronews.com
3. National Cancer Institute. “Cell Phones and Cancer Risk.” National Institutes of Health, 2024. cancer.gov
4. Karipidis K, Baaken D, Loney T, et al. “The Effect of Exposure to Radiofrequency Fields on Cancer Risk in the General and Working Population: A Systematic Review of Human Observational Studies, Part I: Most Researched Outcomes.” Environment International, 2024. pubmed.ncbi.nlm.nih.gov
5. Australian Radiation Protection and Nuclear Safety Agency (ARPANSA). “New Study Adds Evidence Mobile Phones Are Not Associated With Cancer.” ARPANSA, 2025. arpansa.gov.au
6. U.S. Food and Drug Administration. “Reducing Radio Frequency Exposure from Cell Phones.” FDA. fda.gov
7. Federal Trade Commission. “FTC Charges Sellers of Cell Phone Radiation Protection Patches with Making False Claims.” FTC, 2002. ftc.gov
8. Federal Trade Commission. “FTC Settles with Sellers of Bogus Cell Phone Radiation Protection Patches.” FTC, 2003. ftc.gov
9. Australian Radiation Protection and Nuclear Safety Agency (ARPANSA). “Is Electromagnetic Hypersensitivity Really Associated With EMF Exposure?” ARPANSA, 2025. arpansa.gov.au
10. de Vocht F, Röösli M. “Electrohypersensitivity: What Is Belief and What Is Known?” Frontiers in Public Health, 2025. frontiersin.org
11. German Federal Office for Radiation Protection (BfS). Summary of Ledent M, Bordarie J, Vatovez B, et al. “Exposure Perception and Symptom Reporting in Idiopathic Environmental Intolerance Attributed to Electromagnetic Fields Using a Co-Designed Provocation Test.” Bioelectromagnetics, 2025. pubmed.ncbi.nlm.nih.gov
12. World Health Organization. “Radiation: Electromagnetic Fields.” WHO Questions and Answers, 2016. who.int
13. National Institute of Mental Health. “Brain Stimulation Therapies.” National Institutes of Health, 2024. nimh.nih.gov
14. National Center for Complementary and Integrative Health. “Magnets for Pain: What You Need To Know.” National Institutes of Health, 2023. nccih.nih.gov
15. Oschman JL. “Chronic Disease: Are We Missing Something?” Journal of Alternative and Complementary Medicine, 2011. prsinstitute.org