Category: 7. Science

Researchers suspect that two meteorites found in the Sahara Desert in 2023 may originally have come from Mercury, which would make them the first identified fragments of the solar system’s innermost planet.

The least studied and most mysterious of the solar system’s rocky planets, Mercury is so close to the sun that exploring it is difficult even for probes. Only two uncrewed spacecraft have visited it to date — Mariner 10, launched in 1973, and MESSENGER, launched in 2004. A third, BepiColombo, is en route and due to enter orbit around the planet in late 2026.

Scientists know little about Mercury’s geology and composition, and they have never been able to study a fragment of the planet that landed on Earth as a meteorite. In contrast, there are more than 1,100 known samples from the moon and Mars in the database of the Meteoritical Society, an organization that catalogs all known meteorites.

These 1,100 meteorites originated as fragments flung from the surfaces of the moon and Mars during asteroid impacts before making their way to Earth after a journey through space.

Not every planet is likely to eject fragments of itself Earth-ward during collisions. Though Venus is closer to us than Mars is, its greater gravitational pull and thick atmosphere may prevent the launch of impact debris. But some astronomers believe that Mercury should be capable of generating meteors.

“Based on the amount of lunar and Martian meteorites, we should have around 10 Mercury meteorites, according to dynamical modeling,” said Ben Rider-Stokes, a postdoctoral researcher in achondrite meteorites at the UK’s Open University and lead author of a study on the Sahara meteorites, published in June in the journal Icarus.

“However, Mercury is a lot closer to the sun, so anything that’s ejected off Mercury also has to escape the sun’s gravity to get to us. It is dynamically possible, just a lot harder. No one has confidently identified a meteorite from Mercury as of yet,” he said, adding that no mission thus far has been capable of bringing back physical samples from the planet either.

If the two meteorites found in 2023 — named Northwest Africa 15915 (NWA 15915) and Ksar Ghilane 022 (KG 022) — were confirmed to be from Mercury, they would greatly advance scientists’ understanding of the planet, according to Rider-Stokes. But he and his coauthors are the first to warn of some inconsistencies in matching those space rocks to what scientists know about Mercury.

The biggest is that the fragments appear to have formed about 500 million years earlier than the surface of Mercury itself. However, according to Rider-Stokes, this finding could be based on inaccurate estimates, making a conclusive assessment unlikely. “Until we return material from Mercury or visit the surface,” he said, “it will be very difficult to confidently prove, and disprove, a Mercurian origin for these samples.”

But there are some compositional clues that suggest the meteorites might have a link to the planet closest to the sun.

Hints of Mercurian origins

It’s not the first time that known meteorites have been associated with Mercury. The previous best candidate, based on the level of interest it piqued in astronomers, was a fragment called Northwest Africa (NWA) 7325, which was reportedly found in southern Morocco in early 2012.

Rider-Stokes said that was the first meteorite to be potentially associated with Mercury: “It got a lot of attention. A lot of people got very excited about it.” Further analysis, however, showed a richness in chrome at odds with Mercury’s predicted surface composition.

More recently, astronomers have suggested that a class of meteorites called aubrites — from a small meteorite that landed in 1836 in Aubres, France — might come from Mercury’s mantle, the layer below the surface. However, these meteorites lack a chemical compatibility with what astronomers know about the planet’s surface, Rider-Stokes said. “That’s what’s so exciting about the samples that we studied — they have sort of the perfect chemistry to be representative of Mercury,” he said.

Most of what is known about Mercury’s surface and composition comes from NASA’s MESSENGER probe, which assessed the makeup of the planet’s crust from orbit. Both meteorites from the study, which Rider-Stokes analyzed with several instruments including an electron microscope, contain olivine and pyroxene, two iron-poor minerals confirmed by MESSENGER to be present on Mercury.

The new analysis also revealed a complete lack of iron in the space rock samples, which is consistent with scientists’ assumptions about the planet’s surface. However, the meteorites contained only trace amounts of plagioclase, a mineral believed to dominate Mercury’s surface.

The biggest point of uncertainty, though, is still the meteorites’ age. “They are about 4.5 billion years old,” Rider-Stokes said, “and most of Mercury’s surface is only about 4 billion years old, so there’s a 500 million-year difference.”

However, he said he thinks this discrepancy is not sufficient to rule out a Mercurian origin, due to the limited reliability of MESSENGER’s data, which has been also used to estimate the age of Mercury’s surface layer.

“These estimates are based on impact cratering models and not absolute age dating, and therefore may not be entirely accurate,” Rider-Stokes said. “It doesn’t mean that these samples aren’t good analogs for regional areas on the surface of Mercury, or the early Mercurian crust that is not visible on the modern surface of Mercury.”

With more modern instruments now available, BepiColombo, the European Space Agency probe that will start studying Mercury in early 2027, may be able to answer long-standing questions about the planet, such as where it formed and whether it has any water.

Having material confirmed to have come from other planetary bodies helps astronomers understand the nature of early solar system’s building blocks, Rider-Stokes said, and identifying fragments of Mercury would be especially crucial since a mission to gather samples from the planet closest to the sun and bring them back would be extremely challenging and expensive.

Clues to planet formation

Sean Solomon, principal investigator for NASA’s MESSENGER mission to Mercury, said in an email that he believes the two meteorites described in the recent paper likely did not originate from Mercury. Solomon, an adjunct senior research scientist at Columbia University in New York City, was not involved with the study.

The primary reason Solomon cited for his doubts is that the meteorites formed much earlier than the best estimates for the ages of rocks now on Mercury’s surface. But he said he thinks the samples still hold research value.

“Nonetheless, the two meteorites share many geochemical characteristics with Mercury surface materials, including little to no iron … and the presence of sulfur-rich minerals,” he added. “These chemical traits have been interpreted to indicate that Mercury formed from precursor materials much more chemically reduced than those that formed Earth and the other inner planets. It may be that remnants of Mercury precursor materials still remain among meteorite parent bodies somewhere in the inner solar system, so the possibility that these two meteorites sample such materials warrants additional study.”

Solomon also noted that it was difficult to persuade the planetary science community that there were samples from Mars in meteorite collections, and that it took precise matching of their chemistry with data about the surface of Mars taken by the Viking probes to convince researchers to take a closer look. Lunar meteorites were also not broadly acknowledged to be in meteorite collections until after the existence of Martian meteorites had been demonstrated in the 1980s, he added, even though the Apollo and Luna missions had returned abundant samples of lunar materials more than a decade earlier.

Once samples are confirmed to be from a planetary body, Solomon said, they can provide crucial information not available from remote sensing by an orbiting spacecraft on the timing of key geological processes, the history of internal melting of the body, and clues to planet formation and early solar system processes.

Rider-Stokes plans to continue the discussion around these meteorites at the annual meeting of the Meteoritical Society, which takes place in Perth this week. “I’m going to discuss my findings with other academics across the world,” he said. “At the moment, we can’t definitively prove that these aren’t from Mercury, so until that can be done, I think these samples will remain a major topic of debate across the planetary science community.”

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Astronomers have been aware of cosmic vampires, dead stars that hungrily strip plasma from victim stars, for some time. New research suggests that some of these cosmic fiends could have accomplices, Renfields to their Draculas, in the form of a third star in their systems, facilitating their fateful encounter.

These systems are known as cataclysmic variables, and their occupant vampire stars are white dwarfs, the type of stellar remnant that stars with masses around that of the sun leave behind when they die.

Bubbles burst when their caps rupture. Children discover this phenomenon every summer day, but it also underpins key mechanisms for the spread of pollutants, contaminants, and even infectious disease through the generation of aerosol droplets. While bubble bursting has been extensively studied in pure substances, the impact of contaminants on bursting dynamics has not received widespread attention.

Researchers in The Grainger College of Engineering at the University of Illinois Urbana-Champaign have conducted a systematic study to investigate bubble bursting jets – aerosol particles sprayed when bubble surfaces rupture – when surface contaminants are present. The laboratory of mechanical science and engineering professor Jie Feng developed a model predicting the influence of contaminants on jet size and experimentally confirmed it. The study was published in the journal Physical Review Letters, where it was selected as an Editors’ Suggestion.

“Bubbles are commonly formed or intentionally used in many natural and engineered settings,” Feng said. “As they rise due to buoyancy, they become coated with surrounding chemicals, such as micro- and nano-plastics, bio-surfactants, and even bacteria and viruses, and they spread through the fluid jets and the resulting aerosol droplets created when the bubbles burst at an air-liquid interface. This mechanism is crucial in understanding phenomena like airborne contaminants from oil spills and the spread of respiratory diseases, but there have been no systematic studies to date for size quantification of the contaminant-laden droplets. We aim to perform controlled experiments and develop a theoretical framework to predict their size.”

When the cap of a bubble ruptures, a mechanism is triggered by which the focusing of surface waves cause fluid to be ejected – so-called “Worthington jets.” This phenomenon has been studied for decades, but a significant knowledge gap remains. Most research focuses on the case when the bubble surface consists of a pure substance, but many of the most important occurrences involve bubbles with impurities or contaminants.

“For instance, in wastewater treatment ponds contaminated with viruses or bacteria, bubbles formed by mechanical agitation will rise and collect microorganism on their surfaces,” Feng said. “When they escape into the atmosphere and burst, they spray fine droplets that contain these pathogens. Bubble bursting jets pose significant environmental and safety concerns in the area surrounding contaminated aquatic environments, and cleanup efforts need to understand and account for it.”

Finding that there was limited data available and no theoretical work, Feng’s laboratory turned to its capabilities in multi-phase flows to study the phenomenon. To mimic a contaminated bubble, the researchers used a specialized coaxial orifice system that injects gas into water to form bubbles and then coats them with silicone oil. By varying the properties of the oil, the impact of its characteristic on jet features could be studied with a high-speed camera.

“My research has been focusing on fluid mechanics and environmental impacts related to bubble bursting,” said Zhengyu Yang, a graduate student in Feng’s laboratory and the study’s lead author. “We had already established the experimental capabilities required to generate high-quality data on this problem. From there, it was a question of building the right theory to explain what we found.”

The results showed that the size of the ejected aerosol droplets depends on the thickness of the oil layer, the oil’s viscosity and surface tension. To develop a mathematical model explaining this behavior, the researchers introduced a new parameter accounting for the presence of the oil layer. They call this parameter the “revised Ohnesorge number” after the classical Ohnesorge number governing the dynamics of pure bubble bursting jets.

“Our results are valuable for understanding and mitigating airborne transmission of contaminants mediated by bubbles and drops,” Feng said. “To realize their full power, our next step is to consider collective bubble bursting – studies of many bubbles producing aerosol jets at once, which is a more practical scenario in the real world. We hope the tools and knowledge obtained in this research will be broadly applicable to elucidate the mechanistic influence of a variety of contaminated interfaces on multiphase flows.”

Yang Liu of Tsinghua University also contributed to this work.

The study, “Jet Size Prediction in Compound Multiphase Bubble Bursting,” is available online. DOI: 10.1103/PhysRevLett.134.214001

Support was provided by the National Science Foundation and the Campus Research Board of the University of Illinois Urbana-Champaign.

Jie Feng is an Illinois Grainger Engineering assistant professor of mechanical science and engineering in the Department of Mechanical Science and Engineering . He is a research affiliate of the Materials Research Laboratory .

A team of paleontologists from Yale University and Stony Brook University made this discovery after examining fossils from two species of bird-like dinosaurs found in the Gobi Desert in Mongolia.

For years the identity of one of the carpal bones in the wrist of birds was a scientific mystery, until researchers proved it was the pisiform.

This bone was originally a sesamoid bone like a kneecap and had moved from its original position in the wrist to replace the ulnare, another carpal bone.

Its position in modern birds appears to establish linkages that allow birds to fold their wing automatically when the elbow flexes.

The bone’s shape, with a large V-shaped notch, also allows the pisiform of birds to clasp their hand bones to stop them from dislocating during flight.

Therefore, this bone is an important part of a bird’s forelimb and critical to flight.

“The pisiform, in living birds, is an unusual wrist bone in that it initially forms within a muscle tendon, as do bones like your kneecap — but it comes to occupy the position of a ‘normal’ wrist bone called the ulnare,” said Dr. Bhart-Anjan Bhullar, a paleontologist at Yale University.

“Because it is so intimately associated with arm musculature, its incorporation into the wrist ties the muscular flight machinery to wrist motion.”

“This integration is particularly important for stabilizing the wing during flight.”

In their new study, Dr. Bhullar and colleagues analyzed two Late Cretaceous fossils: an unnamed species of troodontid (bird-like raptor related to Velociraptor), and Citipati cf. osmolskae (oviraptorid with a long neck and a toothless beak).

“We were fortunate to have two immaculately preserved theropod wrists for this,” said Yale University paleontologist Alex Ruebenstahl.

“Wrist bones are small and even when they are preserved, they are not in the positions they would occupy in life, having shifted during decay and preservation.”

“Seeing this little bone in the right position cracked it wide open and helped us interpret the wrists of fossils we had on hand and other fossils described in the past.”

“We believe this is the first time a migrated pisiform in a non-bird meat-eating dinosaur has been identified,” said Dr. James Napoli, a vertebrate paleontologist and evolutionary biologist at Stony Brook University

“While we currently do not know precisely how many times dinosaurs learned to fly, it is intriguing that experimentation with flight in these creatures appears only after the pisiform migrated into the wrist joint.”

“Therefore, it is possible this established the automated mechanisms found in current living birds, though we would need to test this hypothesis with more research and analysis of dinosaur wrist bones.”

Putting their findings in evolutionary context, the authors determined that the pisiform moved into its bird-like position not within birds but by the origin of Pennaraptora, a group of theropod dinosaurs that includes dromaeosaurids like Velociraptor, troodontids and oviraptorosaurs.

Overall, this is the group of dinosaurs in which bird-like traits such as feathered wings began to appear, and in which flight evolved at least twice, and possibly up to five times.

“The topological and functional replacement of the ulnare by the pisiform occurred much deeper in theropod history than has been previously understood and was a stepwise process,” the researchers said.

“Over the past few decades, our knowledge of theropod dinosaur anatomy and evolution has increased exponentially, much of it revealing that classically ‘avian’ traits such as thin-walled bones, an enlarged brain, and feathers, all characterize more inclusive groups of theropod dinosaurs.”

“Our results suggest that the construction of the avian wrist is no exception and follows topological patterns laid down by the origin of Pennaraptora.”

The team’s paper was published July 9, 2025 in the journal Nature.

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J.G. Napoli et al. Reorganization of the theropod wrist preceded the origin of avian flight. Nature, published online July 9, 2025; doi: 10.1038/s41586-025-09232-3

NASA research has shown that cell-like compartments called vesicles could form naturally in the lakes of Saturn’s moon Titan.

Titan is the only world apart from Earth that is known to have liquid on its surface. However, Titan’s lakes and seas are not filled with water. Instead, they contain liquid hydrocarbons like ethane and methane.

On Earth, liquid water is thought to have been essential for the origin of life as we know it. Many astrobiologists have wondered whether Titan’s liquids could also provide an environment for the formation of the molecules required for life – either as we know it or perhaps as we don’t know it – to take hold there.

New NASA research, published in the International Journal of Astrobiology, outlines a process by which stable vesicles might form on Titan, based on our current knowledge of the moon’s atmosphere and chemistry. The formation of such compartments is an important step in making the precursors of living cells (or protocells).

The process involves molecules called amphiphiles, which can self-organize into vesicles under the right conditions. On Earth, these polar molecules have two parts, a hydrophobic (water-fearing) end and a hydrophilic (water-loving) end. When they are in water, groups of these molecules can bunch together and form ball-like spheres, like soap bubbles, where the hydrophilic part of the molecule faces outward to interact with the water, thereby ‘protecting’ the hydrophobic part on the inside of the sphere. Under the right conditions, two layers can form creating a cell-like ball with a bilayer membrane that encapsulates a pocket of water on the inside.

When considering vesicle formation on Titan, however, the researchers had to take into account an environment vastly different from the early Earth.

Uncovering Conditions on Titan

Titan is Saturn’s largest moon and the second largest in our solar system. Titan is also the only moon in our solar system with a substantial atmosphere.

The hazy, golden atmosphere of Titan kept the moon shrouded in mystery for much of human history. However, when NASA’s Cassini spacecraft arrived at Saturn in 2004, our views of Titan changed forever.

Thanks to Cassini, we now know Titan has a complex meteorological cycle that actively influences the surface today. Most of Titan’s atmosphere is nitrogen, but there is also a significant amount of methane (CH₄). This methane forms clouds and rain, which falls to the surface to cause erosion and river channels, filling up the lakes and seas. This liquid then evaporates in sunlight to form clouds once again.

This atmospheric activity also allows for complex chemistry to happen. Energy from the Sun breaks apart molecules like methane, and the pieces then reform into complex organic molecules. Many astrobiologists believe that this chemistry could teach us how the molecules necessary for the origin of life formed and evolved on the early Earth.

Building Vesicles on Titan

The new study considered how vesicles might form in the freezing conditions of Titan’s hydrocarbon lakes and seas by focusing on sea-spray droplets, thrown upwards by splashing raindrops. On Titan, both spray droplets and the sea surface could be coated in layers of amphiphiles. If a droplet then lands on the surface of a pond, the two layers of amphiphiles meet to form a double-layered (or bilayer) vesicle, enclosing the original droplet. Over time, many of these vesicles would be dispersed throughout the pond and would interact and compete in an evolutionary process that could lead to primitive protocells.

If the proposed pathway is happening, it would increase our understanding of the conditions in which life might be able to form.

“The existence of any vesicles on Titan would demonstrate an increase in order and complexity, which are conditions necessary for the origin of life,” explains Conor Nixon of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We’re excited about these new ideas because they can open up new directions in Titan research and may change how we search for life on Titan in the future.”

NASA’s first mission to Titan is the upcoming Dragonfly rotorcraft, which will explore the surface of the Saturnian moon. While Titan’s lakes and seas are not a destination for Dragonfly (and the mission won’t carry the light-scattering instrument required to detect such vesicles), the mission will fly from location to location to study the moon’s surface composition, make atmospheric and geophysical measurements, and characterize the habitability of Titan’s environment.

Scientists have detected pesticides in rivers, lakes and oceans worldwide. So what are these pesticides doing to the fish?

Long before pesticides reach lethal doses, they can disrupt hormones, impair brain function and change fish behaviour. Many of these behaviours are essential for healthy ecosystems.

In a new study, my colleagues and I found that pesticides affect many different behaviours in fish. Overall, the chemical pesticides make fish less sociable and interactive. They spend less time gathering in groups, become less protective of their territory, and make fewer attempts to mate.

Imagine the ocean without the vibrant schools of fish we’ve come to love – only isolated swimmers drifting about. Quietly, ecosystems begin to unravel, long before mass die-offs hit the news.

Fish are living and dying in polluted water

Australia is a major producer and user of pesticides, with more than 11,000 approved chemical products routinely used in agricultural and domestic settings. Remarkably, some of these chemicals remain approved in Australia despite being banned in other regions such as the European Union due to safety concerns.

When a tractor or plane sprays pesticides onto crops, it creates a mist of chemicals in the air to kill crop pests. After heavy rain, these chemicals can flow into roadside drains, filter through soil, and slowly move into rivers, lakes and oceans.

Fish swim in this diluted chemical mixture. They can absorb pesticides through their gills or eat contaminated prey.

At high concentrations, mass fish deaths can result, such as those repeatedly observed in the Menindee Lakes. However, doses in the wild often aren’t lethal and more subtle effects can occur. Scientists call these “sub-lethal” effects.

One commonly investigated sub-lethal effect is a change in behaviour – in other words, a change in the way a fish interacts with its surrounding environment.

Our previous research has found most experiments have looked at the impacts on fish in isolation, measuring things such as how far or how fast they swim when pesticides are present.

But fish aren’t solitary — they form groups, defend territory and find mates. These behaviours keep aquatic ecosystems stable. So this time we studied how pesticides affect these crucial social behaviours.

Pesticide exposure makes fish less social

Our study extracted and analysed data from 37 experiments conducted around the world. Together, these tested the impacts of 31 different pesticides on the social behaviour of 11 different fish species.

The evidence suggests pesticides make fish less social, and this finding is consistent across species. Courtship was the most severely impacted behaviour – the process fish use to find and attract mates. This is particularly alarming because successful courtship is essential for healthy fish populations and ecosystem stability.

Next, we found pesticides such as the herbicide glyphosate, which can disrupt brain function and hormone levels had the strongest impacts on fish social behaviours. This raises important questions about how brain function and hormones drive fish social behaviour, which could be tested by scientists in the future.

For example, scientists could test how much a change in testosterone relates to a change in territory defence. Looking at these relationships between what’s going on inside the body mechanisms and outward behaviour will help us better understand the complex impacts of pesticides.

We also identified gaps in the current studies. Most existing studies focus on a limited number of easy-to-study “model species” such as zebrafish, medaka and guppies. They also often use pesticide dosages and durations that may not reflect real-world realities.

Addressing these gaps by including a range of species and environmentally relevant dosages is crucial to understanding how pesticides affect fish in the wild.

Behaviour is a blind spot in regulation

Regulatory authorities should begin to recognise behaviour as a reliable and important indicator of pesticide safety. This can help them catch pesticide pollution early, before mass deaths occur.

Scientists play a crucial role too. By following the same methods, scientists can produce comparable results. A standardised method then provides regulators the evidence needed to confidently assess pesticide risks.

Together, regulatory authorities and scientists can find a way to use behavioural studies to help inform policy decisions. This will help to prevent mass deaths and catch pesticide impacts early on.

Leave no stone unturned in restoring our waters

Rivers, lakes, oceans and reefs are bearing the brunt of an ever-growing human footprint.

So far, much of the spotlight has focused on reducing carbon emissions and managing overfishing — and rightly so. But there’s another, quieter threat drifting beneath the surface: the chemicals we use.

Pesticides used on farms and in gardens are being detected everywhere, even iconic ecosystems such as the Great Barrier Reef. As we have shown, these pesticides can have disturbing effects even at low concentrations.

Now is the time to cut pesticide use and reduce runoff. Through switching to less toxic chemicals and introducing better regulations, we can reduce the damage. If we act with urgency, we can limit the impacts pesticides have on our planet.

It was the scariest choking incident David Palumbo had ever seen.

The 88-year-old man had been dining at a Providence, Rhode Island, Italian restaurant in September 2019. Now he was unconscious, with a piece of bread lodged in his windpipe. Precious minutes went by as first responders were unable to help him with CPR or the Heimlich maneuver.

In an ambulance on the way to the hospital, the elderly man’s skin was blue, and firefighters worried he was going to die. Palumbo — a fire department captain — used a scissors-like device called Magill forceps to pull the bread from the man’s throat.

“We get a lot of calls in the city for choking,” many of which are resolved before emergency responders even get there, Palumbo added. “This was by far the worst one I’ve been on in my career.”

Fortunately, the man survived and made a full recovery, he said.

But many elderly people do not. Each year, choking claims the lives of more than 4,100 Americans who are 65 or older. It’s the most vulnerable age group, accounting for about three-quarters of U.S. choking deaths, according to federal health statistics.

The death rate has been relatively steady, but the number has risen, as the size of the nation’s retirement-age population grows.

In response, a number of companies are marketing anti-choking devices to the elderly. Medical professionals have been debating whether to endorse the products, sold under the names LifeVac, SaveLix, VitalVac and the Dechoker.

Dr. Nathan Charlton, a University of Virginia professor of emergency medicine who advises the American Red Cross on first aid, said there is limited evidence for the products and that the Red Cross is still evaluating them.

Here’s a look at choking and the best ways to prevent choking deaths.

Choking is a danger to older adults

Choking occurs when food or some other object partially or totally blocks the windpipe, preventing oxygen from reaching the lungs.

Telltale signs include someone reaching for their neck and losing the ability to speak normally. Brain damage can occur after four minutes, and death can come just a few minutes later.

Older adults are at higher risk for a number of reasons. As people get older, mouth and throat muscles can weaken. Older people also make less saliva. Some chronic diseases and medications can make swallowing even harder. Dentures can be a choking risk.

The best ways to stop choking

Choking risk can be reduced by cutting food into small pieces, chewing food slowly, drinking plenty of liquids with meals, and not laughing or talking at the same time you are chewing and swallowing.

When someone is choking, you can try perhaps the oldest form of first aid: back slaps.

There’s also the Heimlich maneuver, named after the doctor credited with devising it in the 1970s. It involves standing behind the choking person, wrapping your arms around their abdomen and — with a balled fist — thrusting inward and upward. The idea is that it forces air out of the lungs, and the obstruction with it.

The American Red Cross recommends alternating back blows and abdominal thrusts in sets of five.

That’s for situations in which someone is around to help a choking victim. But what if they are alone?

It is possible for someone try to self-administer a Heimlich by thrusting their abdomen against the back of a chair, Charlton said.

Makers of some the newer anti-choking devices say that’s where their products can make a difference.

“Elderly people probably are not capable of diving on a chair or counter,” said Arthur Lih, the founder and chief executive of LifeVac.

Anti-choking devices aren’t always risk-free

They vary in design, but generally the devices look like a face mask attached to a tube or bellows, with a handle at the end. They typically sell for around $30 to $100.

A choking person dons the mask, pushes down on the handle and then pulls up. That is supposed to create a suction that would pull out the blockage.

Some research suggests at least certain devices can injure the tongue or cause bleeding and swelling in the throat. And the U.S. Food and Drug Administration has reports that some products did not generate enough suction and left people with bruising around the face, lips, and mouth.

An injury report led the FDA to do an inspection and issue a warning letter to Dechoker in 2021.

Manufacturers note their products are registered with the FDA, but that’s not the same as an endorsement. Indeed, the agency last year issued a notice to consumers that said it has not approved anti-choking devices sold over the counter, because their safety and effectiveness haven’t been established.

Lih said the FDA action was in response to the proliferation of anti-choking devices entering the market that vary in design and quality.

More research is needed, choking expert says

Right now, the consensus — even among anti-choking device manufacturers — is that back blows and abdominal thrusts should always be tried first. (The forceps that Palumbo used are not recommended for the general public.)

Lih said thousands of nursing homes and emergency response agencies have purchased the newer anti-choking devices.

One example: The police department in Acworth, Georgia, bought about 75 LifeVac devices after an officer last year used her personal device to save an elderly woman. They are now in every patrol car, said Sgt. Eric Mistretta.

Manufacturers claim the products have saved thousands of lives across multiple countries, but it’s tricky to document how well they actually work, said Dr. Cody Dunne, a University of Calgary researcher who has tried.

The early evidence has come from case reports or small studies that used mannequins and cadavers.

“I think the case is definitely being built,” he said, but more rigorous research is needed. For example, a larger study could compare what happened during choking incidents at nursing homes that stock the devices with those that don’t.

Dunne noted, however, that evidence for the Heimlich maneuver and back slaps is evolving, too. He co-authored a study last year that found back blows worked better than the Heimlich or chest compressions.

“We’re only now getting good evidence on the old choking techniques, let alone these new ones,” he said.

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