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E-cigarettes have become increasingly popular over the last two decades, especially among young people. These sleek, deliciously flavored smoking devices are often marketed as a safer alternative to conventional cigarettes, but alarming new research challenges that assumption.

In a study published June 25 in the journal ACS Central Science, researchers tested three popular disposable vape brands for hazardous metals and metalloids such as lead, chromium, antimony, and nickel. Inhaling these toxins can increase the risk of cancer, respiratory disease, and nerve damage. The findings show that e-cigarettes emit dangerously high levels of toxic metals—orders of magnitude higher than levels emitted by traditional cigarettes and other e-cigarettes. One brand released more lead during a day’s use than nearly 20 packs of cigarettes. Given the widespread underage use of vapes, the findings underscore an urgent need for regulatory action, the researchers conclude.

“Our study highlights the hidden risk of these new and popular disposable electronic cigarettes—with hazardous levels of neurotoxic lead and carcinogenic nickel and antimony—which stresses the need for urgency in enforcement,” co-author Brett Poulin, an assistant professor of environmental toxicology at the University of California, Davis, said in a statement. “These risks are not just worse than other e-cigarettes but worse in some cases than traditional cigarettes.”

The Food and Drug Administration (FDA) has cracked down on brands selling flavored, disposable vapes in the U.S. due to concerns about youth access, health risks, and unauthorized sales. Despite issuing warning letters to popular brands, slapping retailers with civil penalties, and blocking e-cigarette imports from other countries such as China, the agency has failed to keep these devices out of the U.S. market.

In the past few years, sales of disposable vapes have overtaken sales of older, refillable vapes. According to the FDA’s Annual National Youth Tobacco Survey for 2025, disposable e-cigarettes are the most commonly used tobacco product among young people. The survey found that 5.9% of middle and high school students (1.63 million) reported current use of e-cigarettes, and of those students, 55.6% use disposable vapes.

Previous studies have investigated the elemental composition of refillable e-cigarettes, but few have looked into these newer devices. To fill that gap, Poulin and his colleagues analyzed the metals and metalloids inside seven disposable vapes made by three brands, including flavored and unflavored liquids. They selected the brands based on popularity and purchased the e-cigarettes from online vendors based in the U.S. All the devices they tested contained nicotine except one, which allowed the researchers to test if nicotine influences the metal concentrations of e-liquids (commonly known as “vape juice”).

The key components of any vape are a battery, e-liquid (commonly known as “vape juice” or “e-juice), and a heating coil. When the user presses a button on the device or—in some cases—simply inhales, the battery heats the coil and turns the e-liquid into an aerosol. These metal components can leach into the e-liquid and thus work their way into the lungs.

The researchers tested the metal concentrations of unused e-liquids and aerosols, using a special instrument to activate the e-cigarettes and generate between 500 and 1,500 puffs per device. They found that “these disposable devices have toxins already present in the e-liquid, or they’re leaching quite extensively from their components into e-liquids and ultimately transferred to the smoke,” lead author Mark Salazar, a PhD candidate in Poulin’s lab, said in the statement.

Some unused e-liquids contained high levels of antimony, a toxic metalloid. Heating coils leached nickel into the e-liquid, while leaded bronze alloy components in some devices leached nickel and lead. The vapors of some devices contained surprisingly high metal levels, including antimony and lead. Interestingly, the metal concentrations of the aerosols increased as the number of puffs increased, suggesting that exposure worsens as the device ages.

Overall, the researchers determined that disposable e-cigarette users are exposed to markedly higher levels of toxic metals and metalloids than those who use refillable vapes, which may lead to increased health risks. Three of the tested vapes produced vapors that contained nickel levels that exceeded cancer risk thresholds, and two emitted potentially cancerous amounts of antimony. Four devices had nickel and lead emissions that surpassed risk thresholds for illnesses besides cancer, such as neurological damage and respiratory disease.

Of the nearly 100 disposable e-cigarette brands available in the U.S., this study tested only three. Despite regulatory efforts, these devices remain wildly popular among adolescents. The researchers hope that their work inspires others to investigate the health risks associated with disposable e-cigarettes, as it would appear they won’t be going away anytime soon.

Over the past three decades there have been amazing advances in treating and preventing HIV.

It’s now a manageable infection. A person with HIV who takes HIV medicine consistently, before their immune system declines, can expect to live almost as long as someone without HIV .

The same drugs prevent transmission of the virus to sexual partners.

There is still no effective HIV vaccine . But there are highly effective drugs to prevent HIV infection for people without HIV who are at higher risk of acquiring it.

These drugs are known as as “pre-exposure prophylaxis” or PrEP . These come as a pill, which needs to be taken either daily, or ” on demand ” before and after risky sex. An injection that protects against HIV for six months has recently been approved in the United States .

So with such effective HIV treatment and PrEP, why are we still spending millions looking for HIV cures?

Not everyone has access to these drugs

Access to HIV drugs and PrEP depends on the availability of health clinics, health professionals, and the means to supply and distribute the drugs. In some countries, this infrastructure may not be secure.

For instance, earlier this year, US President Donald Trump’s dissolution of the USAID foreign aid program has threatened the delivery of HIV drugs to many low-income countries.

This demonstrates the fragility of current approaches to treatment and prevention. A secure, uninterrupted supply of HIV medicine is required, and without this, lives will be lost and the number of new cases of HIV will rise.

Another example is the six-monthly PrEP injection just approved in the US. This drug has great potential for controlling HIV if it is made available and affordable in countries with the greatest HIV burden.

But the prospect for lower-income countries accessing this expensive drug looks uncertain, even if it can be made at a fraction of its current cost, as some researchers say .

So despite the success of HIV drugs and PrEP, precarious health-care systems and high drug costs mean we can’t rely on them to bring an end to the ongoing global HIV pandemic. That’s why we also still need to look at other options.

Haven’t people already been ‘cured’?

Worldwide, at least seven people have been “cured” of HIV – or at least have had long-term sustained remission. This means that after stopping HIV drugs, they did not have any replicating HIV in their blood for months or years.

In each case, the person with HIV also had a life-threatening cancer needing a bone marrow transplant. They were each matched with a donor who had a specific genetic variation that resulted in not having HIV receptors in key bone marrow cells.

After the bone marrow transplant, recipients stopped HIV drugs, without detectable levels of the virus returning. The new immune cells made in the transplanted bone marrow lacked the HIV receptors. This stopped the virus from infecting cells and replicating.

But this genetic variation is very rare . Bone marrow transplantation is also risky and extremely resource-intensive . So while this strategy has worked for a few people, it is not a scalable prospect for curing HIV more widely.

So we need to keep looking for other options for a cure, including basic laboratory research to get us there.

How about the ‘breakthrough’ I’ve heard about?

HIV treatment stops the HIV replication that causes immune damage. But there are places in the body where the virus “hides” and drugs cannot reach. If the drugs are stopped, the “latent” HIV comes out of hiding and replicates again. So it can damage the immune system, leading to HIV-related disease.

One approach is to try to force the hidden or latent HIV out into the open, so drugs can target it. This is a strategy called “shock and kill”. And an example of such Australian research was recently reported in the media as a ” breakthrough ” in the search for an HIV cure.

Researchers in Melbourne have developed a lipid nanoparticle – a tiny ball of fat – that encapsulates messenger RNA (or mRNA) and delivers a “message” to infected white blood cells. This prompts the cells to reveal the “hiding” HIV.

In theory, this will allow the immune system or HIV drugs to target the virus.

This discovery is an important step. However, it is still in the laboratory phase of testing, and is just one piece of the puzzle.

We could say the same about many other results heralded as moving closer to a cure for HIV .

Further research on safety and efficacy is needed before testing in human clinical trials. Such trials start with small numbers and the trialling process takes many years. This and other steps towards a cure are slow and expensive, but necessary.

Importantly, any cure would ultimately need to be fairly low-tech to deliver for it to be feasible and affordable in low-income countries globally .

So where does that leave us?

A cure for HIV that is affordable and scalable would have a profound impact on human heath globally, particularly for people living with HIV . To get there is a long and arduous path that involves solving a range of scientific puzzles, followed by addressing implementation challenges.

In the meantime, ensuring people at risk of HIV have access to testing and prevention interventions – such as PrEP and safe injecting equipment – remains crucial. People living with HIV also need sustained access to effective treatment – regardless of where they live.

Bridget Haire has received funding from the National Health and Medical Research Council. She is a past president of the Australian Federation of AIDS Organisations (now Health Equity Matters).

Benjamin Bavinton receives funding from the National Health and Medical Research Council, the Australian government, and state and territory governments. He also receives funding from ViiV Healthcare and Gilead Sciences, both of which make drugs or drug classes mentioned in this article. He is a Board Director of community organisation, ACON, and is on the National PrEP Guidelines Panel coordinated by ASHM Health.

/Courtesy of The Conversation. This material from the originating organization/author(s) might be of the point-in-time nature, and edited for clarity, style and length. Mirage.News does not take institutional positions or sides, and all views, positions, and conclusions expressed herein are solely those of the author(s).