Category: English

Source: The Conversation – Global Perspectives – By Anjum Naweed, Professor of Human Factors, CQUniversity Australia

This article contains spoilers!

I once leapt out of a train carriage because two strangers were loudly discussing the ending of the last Harry Potter book. Okay – I didn’t leap, but I did plug my ears and flee to another carriage.

Recently, I found myself in a similar predicament, trapped on a bus, entirely at the mercy of two passengers dissecting the Severance season two finale.

But not everyone shares my spoiler anxiety. I have friends who flip to the last page of a book before they’ve read the first one, or who look up the ending before hitting play. According to them, they simply need to know.

So why do some of us crave surprise and suspense, while others find comfort in instant resolution?

What’s in a spoiler?

Spoilers have become a cultural flashpoint in the age of streaming, social media and shared fandoms.

Researchers define “spoiler” as undesired information about how a narrative’s arc will conclude. I often hear “spoilers!” interjected mid-sentence, a desperate protest to protect narrative ignorance.

Hitchcock’s twist-heavy Psycho elevated spoiler sensitivity. Its release came with an anti-spoilers policy including strict viewing times, lobby warnings recorded by the auteur himself, and even real policemen urging “total enjoyment”. A bold ad campaign implored audiences against “cheating yourselves”.

The twists were fiercely protected.

Even the Star Wars cast didn’t know Darth Vader’s paternity twist until premiere night. Avenger’s Endgame filmed multiple endings and used fake scripting to mislead its stars. And Andrew Garfield flat-out lied about his return to Spider-Man: No Way Home – a performance worthy of an Oscar – all for the sake of fan surprise and enjoyment.

But do spoilers actually ruin the fun, or just shift how we experience it?

The satisfaction of a good ending

In 2014, a Dutch study found that viewers of unspoiled stories experienced greater emotional arousal and enjoyment. Spoilers may complete our “mental models” of the plot, making us less driven to engage, process events, or savour the unfolding story.

But we are also likely to overestimate the negative effect of a spoiler on our enjoyment. In 2016, a series of studies involving short stories, mystery fiction and films found that spoiled participants still reported high levels of enjoyment – because once we’re immersed, emotional connection tends to eclipse what we already know.

But suspense and enjoyment are complex bedfellows.

American media psychology trailblazer Dolf Zillmann said that suspense builds tension and excitement, but we only enjoy that tension once the ending lands well.

The thrill isn’t fun while we’re hanging in uncertainty – it’s the satisfying resolution that retroactively makes it feel good.

That could be why we scramble for an “ending explained” when a film or show drops the ball on closure. We’re trying to resolve uncertainty and settle our emotions.

Spoilers can also take the pressure off. A 2009 study of Lost fans found those who looked up how an episode would end actually enjoyed it more. The researchers found it reduced cognitive pressure, and gave them more room to reflect and soak in the story.

Spoilers put the audience back in the driver’s seat – even if filmmakers would rather keep hold of the wheel. People may seek spoilers out of curiosity or impatience, but sometimes it’s a quiet rebellion: a way to push back against the control creators hold over when and how things unfold.

That’s why spoilers are fertile ground for power dynamics. Ethicists even liken being spoiled to kind of moral trespass: how dare someone else make that decision for me?!

But whether you avoid spoilers or seek them out, the motive is often the same: a need to feel in control.

Shaping your emotions

Spoiler avoiders crave affect: they want emotional transportation.

When suspense is part of the pleasure, control means choosing when and how that knowledge lands. There’s a mental challenge to be had in riding the story as it unfolds, and a joy in seeing it click into place.

That’s why people get protective, and even chatter about long-aired shows can spark outrage. It’s an attempt to police the commentary and preserve the experience for those still waiting to be transported.

Spoiler seekers want control too, just a different kind. They’re not avoiding emotion, they’re just managing it. A spoiler affords control over our negative emotions, but also softens the blow, and inoculates us against anxiety.

Psychologists dub this a “non-cognitive desensitisation strategy” to manage surprise, a kind of “emotional spoiler shield” to protect our attachments to shows and characters, and remind us that TV, film and book narratives are not real when storylines hit close to home.

Knowing what happens turns into a subtle form of self-regulation.

So, what did I do when Severance spoilers floated by? Did I get off the bus? Nope, I stayed put and faced the beast. As I tried to make sense of the unfamiliar plot points (The macrodata means what? Mark stays where?), I found the unexpected chance to dive deeper.

Maybe surprise is not the sum of what makes something entertaining and worth engaging with. Spoiler alert! It’s good to have an end to journey towards, but it’s the journey that matters, in the end.

Anjum Naweed does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. ‘Don’t tell me!’ Why some people love spoilers – and others will run a mile – https://theconversation.com/dont-tell-me-why-some-people-love-spoilers-and-others-will-run-a-mile-256803

Source: The Conversation – Global Perspectives – By Heike Schanzel, Professor of Social Sustainability in Tourism, Auckland University of Technology

Tourists in Kathmandu are tempted everywhere by advertisements for trekking expeditions to Everest Base Camp. If you didn’t know better, you might think it’s just a nice hike in the Nepalese countryside.

Typically the lower staging post for attempts on the summit, the camp is still 5,364 metres above sea level and a destination in its own right. Travel agencies say no prior experience is required, and all equipment will be provided. Social media, too, is filled with posts enticing potential trekkers to make the iconic journey.

But there is a real risk of creating a false sense of security. An exciting adventure can quickly turn into a struggle for survival, especially for novice mountaineers.

Nevertheless, Sagarmatha National Park is deservedly popular for its natural beauty and the allure of the world’s highest peak, Chomolungma (Mount Everest). It is also home to the ethnically distinctive Sherpa community.

Consequently, the routes to Everest Base Camp are among the busiest in the Himalayas, with nearly 60,000 tourists visiting the area each year. There are two distinct trekking seasons: spring (March to May) and autumn (September to October).

High mountains require everyone to be properly prepared. Events which under normal conditions might be a minor inconvenience can be magnified in such an environment and pose a serious risk.

Even at the start of the trek in Lukla (2,860m), one is exposed to factors that can directly or indirectly affect one’s health, especially altitude mountain sickness or unfamiliar bacteria.

We interviewed 24 trekkers in May this year, as well as 60 residents and business owners in May 2023, to explore some of the safety issues anyone considering heading to base camp should be aware of.

Life at high altitude

First, it’s vital to choose goals within one’s technical and physical capabilities. While the human body can adapt to altitudes of up to 5,300m, the potential risk of altitude mountain sickness can occur at only 2,500m – lower than Lukla.

Proper acclimatisation above 3,000m means ascending no more than 500m a day and resting every two to three days at the same altitude. The optimal (though rarely followed) approach is the “saw tooth system” of climbing during the day but descending to sleep at a lower level.

Residents of the Khumbu region (on the Nepalese side of Everest) are familiar with the problem of tourists not acclimatising, or not paying attention to their surroundings. As one hotel owner said, pointing to a trekker setting out:

He’s going uphill and it’s already late. It’s going to get dark and cold soon. He won’t make it to the next settlement. We have to report this to the authorities or go after him ourselves.

Inexperienced trekkers should hire a local guide. Several we interviewed had needed medical evacuation, including a woman in her mid-20s who had to leave base camp after one night. She found her guides – not locals – online. But they never checked her vital signs during the trek:

[The doctors] said that I had high-altitude pulmonary edema […] it was just really important to come down the elevation. And if I had tried to go higher, it probably would have been really bad.

Health checks throughout the trek are imperative. This includes assessing the four main symptoms of altitude mountain sickness: headache, nausea, dizziness and fatigue. If they appear, the trekker shouldn’t go higher and might even need to descend.

Take time to adapt

Using a reputable local trekking agency might be more expensive, but it will help ensure safety and also familiarise the visitor with the local culture, helping avoid negative impacts on the host community.

Too often, the primary goal of trekkers is a photo on the famous rock at base camp. Once obtained, many simply take a helicopter back to Kathmandu. As a helicopter tour agency owner said:

They don’t want to get back on their feet. The goal, after all, has been achieved. In general, tourists used to be much better prepared. Now they know they can return by helicopter.

Helicopter travel can be dangerous on its own, of course. But this tendency to view the trek as a one-way trip also affects host-guest relations and can irritate local communities.

It’s also important to monitor your food and drink intake and watch for signs of food poisoning. Diarrhoea at high altitudes is particularly dangerous because it leads to rapid dehydration – hard to combat in mountain conditions.

Low air pressure and reduced oxygen exacerbate the condition, weakening the body’s ability to recover. Also, the symptoms of dehydration can resemble altitude mountain sickness.

When travelling in other climate zones or countries with different sanitary standards, there is inevitable contact with strains of bacteria not present in one’s natural microbiome.

A good solution is to spend a few days naturally adapting to bacterial flora at a lower altitude in Nepal before heading to the mountains. Also, try to eat the local food, such as daal bhat, Nepal’s national dish. According to one hotel owner in Pangboche:

Tourists demand strange food from us – pizza, spaghetti, Caesar salad – and then are angry that it doesn’t taste the way they want. This is not our food. You should probably eat local food.

Most of the trekkers we interviewed during this spring season reported experiencing gastrointestinal issues, often for several days.

Overall, diarrhoea-related infections are the leading cause of illness among travellers, including base camp trekkers. Studies conducted in the Himalayas show as many as 14% of mountain tourists contract gastroenteritis, accounting for about 10% of all helicopter evacuations.

In the end, the commonest cause of failure or accident in the mountains is overestimating one’s abilities – what has been called “bad judgement syndrome” – when the route is too hard, the pace too fast, or there’s been too little time spent acclimatising.

A simple solution: walk slowly and enjoy the views.

Michal Apollo receives funding from the National Science Centre NCN Poland, the small-scale project awarded by the Institute of Earth Sciences, and the Research Excellence Initiative of the University of Silesia in Katowice. He is affiliated with the Global Justice Program, Yale University, and Academics Stand Against Poverty.

Heike Schanzel does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Thinking of trekking to Everest Base Camp? Don’t leave home without this expert advice – https://theconversation.com/thinking-of-trekking-to-everest-base-camp-dont-leave-home-without-this-expert-advice-260497

Source: The Conversation – Global Perspectives – By Michael Wilson, Research Fellow and PhD Candidate in Men’s Mental Health, The University of Melbourne

Breakups hurt. Emotional and psychological distress are common when intimate relationships break down. For some people, this distress can be so overwhelming that it leads to suicidal thoughts and behaviours.

This problem seems especially the case for men. Intimate partner problems including breakups, separation and divorce feature in the paths to suicide among one in three Australian men aged 25 to 44 who end their lives.

Men account for three in every four suicides in many nations worldwide, including Australia. So improving our understanding of links between relationship breakdown and men’s suicide risk has life-saving potential.

Our research, published today, is the first large-scale review of the evidence to focus on understanding men’s risk of suicide after a breakup. We found separated men were nearly five times more likely to die by suicide compared to married men.

What did we find?

We brought together findings from 75 studies across 30 countries worldwide, involving more than 106 million men.

We focused on understanding why relationship breakdown can lead to suicide in men, and which men are most at risk. We might not be able to prevent breakups from happening, but we can promote healthy adjustment to the stress of relationship breakdown to try and prevent suicide.

Overall, we found divorced men were 2.8 times more likely to take their lives than married men.

For separated men, the risk was much higher. We found that separated men were 4.8 times more likely to die by suicide than married men.

Most strikingly, we found separated men under 35 years of age had nearly nine times greater odds of suicide than married men of the same age.

The short-term period after relationship breakdown therefore appears particularly risky for men’s mental health.

What are these men feeling?

Some men’s difficulties regulating the intense emotional stress of relationship breakdown can play a role in their suicide risk. For some men, the emotional pain tied to separation – deep sadness, shame, guilt, anxiety and loss – can be so intense it feels never-ending.

Many men are raised in a culture of masculinity that often encourages them to suppress or withdraw from their emotions in times of intense stress.

Some men also experience difficulties understanding or interpreting their emotions, which can create challenges in knowing how to respond to them.

Overall, our research found relationship breakdown may lead to suicide for some men because of the complex interaction between the individual (emotional distress) and interpersonal (changes in their social network and availability of support) impacts of a breakup.

Many of these impacts don’t seem to feature in the paths to suicide after a breakup for women in the same way.

Breakups also impact social networks

As intimate relationships become more serious, we tend to spend less time investing in our friendships, especially if juggling the demands of a career and family.

Many men, especially in heterosexual relationships, rely on their intimate partner as a primary source of social and emotional support – often at the expense of connections outside their relationship.

This can create a risky situation if relationships break down, as it seems many men are left with little support to turn to. This rang true in our research, as men’s social disconnection and loneliness seemed to increase their suicide risk following relationship breakdown.

We also know people can struggle to know how to support men after a breakup. Research has found some men who ask for support are told to just “get back on the horse”. Such a response invalidates men’s pain and reinforces masculine stereotypes that relationship breakdown doesn’t affect them.

So, what can we do?

There is no simple answer to preventing suicide following relationship breakdown, but a range of opportunities exist.

We can intervene early, by educating young people with the skills to end relationships healthily, handle rejection and regulate the difficult emotions of a breakup.

We can embed support groups and other opportunities for connection and peer support in relationship services that are regularly in contact with those navigating separation, to help combat loneliness.

We can ensure mental health practitioners are equipped with the skills necessary to engage and respond effectively to men who seek help following a breakup, to help keep them safe until they can get back on their feet.

Most importantly, if men come to any of us seeking support after a breakup, we can remember that time is often a great healer. The best we can do is sit with men in their pain, rather than try and get them to stop feeling it. This connection could be life-saving.

Support and information is available at Relationships Australia and MensLine Australia. If this article has raised issues for you, or if you’re concerned about someone you know, call Lifeline on 13 11 14.

Michael Wilson works for The University of Melbourne and consults to Movember. He receives funding from the Australian Government Research Training Program Scholarship, provided by the Australian Commonwealth Government and the University of Melbourne.

Jacqui Macdonald receives funding from the National Health and Medical Research Council’s Medical Research Future Fund and the Australian Research Council. She convenes the Australian Fatherhood Research Consortium and she is on the Movember Global Men’s Health Advisory Committee.

Zac Seidler has been awarded an NHMRC Investigator Grant. He is also the Global Director of Research with the Movember Institute of Men’s Health. He advises government on men’s suicide, masculinities, violence prevention and social media policy.

– ref. Separated men are nearly 5 times more likely to take their lives than married men – https://theconversation.com/separated-men-are-nearly-5-times-more-likely-to-take-their-lives-than-married-men-258196

Source: The Conversation – Global Perspectives – By Nicole Rinehart, Nicole Rinehart, Professor, Clinical Psychology, Director of the Neurodevelopment Program, School of Psychological Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University

Autism is a neurodevelopmental condition that affects how people’s brains develop and function, impacting behaviour, communication and socialising. It can also involve differences in the way you move and walk – known as your “gait”.

Having an “odd gait” is now listed in the Diagnostic and Statistical Manual of Mental Disorders as a supporting diagnostic feature of autism.

What does this look like?

The most noticeable gait differences among autistic people are:

• toe-walking, walking on the balls of the feet
• in-toeing, walking with one or both feet turned inwards
• out-toeing, walking with one or both feet turned out.

Research has also identified more subtle differences. A study summarising 30 years of research among autistic people reports that gait is characterised by:

• walking more slowly
• taking wider steps
• spending longer in the “stance” phase, when the foot leaves the ground
• taking more time to complete each step.

Autistic people show much more personal variability in the length and speed of their strides, as well as their walking speed.

Gait differences also tend to occur alongside other motor differences, such as issues with balance, coordination, postural stability and handwriting. Autistic people may need support for these other motor skills.

What causes gait differences?

These are largely due to differences in brain development, specifically in areas known as the basal ganglia and cerebellum.

The basal ganglia are broadly responsible for sequencing movement including through shifting posture. It ensures your gait appears effortless, smooth and automatic.

The cerebellum then uses visual and proprioceptive information (to sense the body’s position and movement) to adjust and time movements to maintain postural stability. It ensures movement is controlled and coordinated.

Developmental differences in these brain regions relate to the way the areas look (their structure), how they work (their function and activation) and how they “speak” to other areas of the brain (their connections).

While some researchers have suggested that autistic gait occurs due to delayed development, we now know gait differences persist across the lifespan. Some differences actually become clearer with age.

In addition to brain-based differences, the autistic gait is also associated with factors such as the person’s broader motor, language and cognitive capabilities.

People with more complex support needs might have more pronounced gait or motor differences, together with language and cognitive difficulties.

Motor dysregulation might indicate sensory or cognitive overload and be a useful marker that the person might benefit from extra support or a break.

How is it managed?

Not all differences need to be treated. Instead, clinicians take an individualised and goals-based approach.

Some autistic people might have subtle gait differences that are observable during testing. But if these differences don’t impact a person’s ability to participate in everyday life, they don’t require support.

An autistic person is likely to benefit from support for gait differences if they have a functional impact on their daily life. This might include:

• increased risk of, or frequent, falls
• difficulty participating in the physical activities they enjoy
• physical consequences such as tightness of the Achilles and calf muscles, or associated pain in other areas, such as the feet or back.

Some children may also benefit from support for motor skill development. However this doesn’t have to occur in a clinic.

Given children spend a large portion of their time at school, programs that integrate opportunities for movement throughout the school day allow autistic children to develop motor skills outside of the clinic and alongside peers. We developed the Joy of Moving Program in Australia, for example, which gets students moving in the classroom.

Our community-based intervention studies show autistic children’s movement abilities can improve after engaging in community-based interventions, such as sports or dance.

Community-based support models empower autistic children to have agency in how they move, rather than seeing different ways of moving as a problem to be fixed.

Where to from here?

While we have learnt a lot about autistic gait at a broad level, researchers and clinicians are still seeking a better understanding of why and when individual variability occurs.

We’re also still determining how to best support individual movement styles, including among children as they develop.

However there is growing evidence that physical activity enhances social skills and behavioural regulation in preschool children with autism.

So it’s encouraging that states and territories are moving towards more community-based foundational supports for autistic children and their peers, as governments develop supports outside the National Disability Insurance Scheme (NDIS).

The authors thank the late Emeritus Professor John Bradshaw for his early input into this piece.

Nicole Rinehart receives funding from: Moose Happy Kids Foundation, MECCA M-Power, the Grace & Emilio Foundation, Ferrero Australia, as part of the global Kinder Joy of moving program, Aspen Pharmacare Australia Pty Ltd, Jonathan and Simone Wenig, Adam Krongold, the Grosman Family Foundation, the Shoreline Foundation, the Victorian Department of Education, the NSW Department of Education, and the Department of Social Services – Information, Linkages and Capacity Building (ILC) Program, and has worked in partnership with the Australian Football League.

Chloe Emonson works on projects that receive funding from: Moose Happy Kids Foundation, MECCA M-Power, the Grace & Emilio Foundation, Ferrero Australia, as part of the global Kinder Joy of moving program, Aspen Pharmacare Australia Pty Ltd, Jonathan and Simone Wenig, Adam Krongold, the Grosman Family Foundation, the Shoreline Foundation, the Victorian Department of Education, the NSW Department of Education, and the Department of Social Services – Information, Linkages and Capacity Building (ILC) Program, and has worked in partnership with the Australian Football League.

Ebony Lindor works on projects that receive funding from: Moose Happy Kids Foundation, MECCA M-Power, the Grace & Emilio Foundation, Ferrero Australia, as part of the global Kinder Joy of moving program, Aspen Pharmacare Australia Pty Ltd, Jonathan and Simone Wenig, Adam Krongold, the Grosman Family Foundation, the Shoreline Foundation, the Victorian Department of Education, the NSW Department of Education, and the Department of Social Services – Information, Linkages and Capacity Building (ILC) Program, and has worked in partnership with the Australian Football League.

– ref. Why do some autistic people walk differently? – https://theconversation.com/why-do-some-autistic-people-walk-differently-231685

Source: The Conversation – Global Perspectives – By Mathieu Duval, Adjunct Senior Researcher at Griffith University and La Trobe University, and Ramón y Cajal (Senior) Research Fellow, Centro Nacional de Investigación sobre la Evolución Humana (CENIEH)

Fossils are invaluable archives of the past. They preserve details about living things from a few thousand to hundreds of millions of years ago.

Studying fossils can help us understand the evolution of species over time, and glimpse snapshots of past environments and climates. Fossils can also reveal the diets or migration patterns of long-gone species – including our own ancestors.

But when living things turn to rock, discerning those details is no easy feat. One common technique for studying fossils is micro-computerised tomography or micro-CT. It’s been used to find the earliest evidence of bone cancer in humans, to study brain imprints and inner ears in early hominins, and to study the teeth of the oldest human modern remains outside Africa, among many other examples.

However, our new study, published today in Radiocarbon, shows that despite being widely regarded as non-destructive, micro-CT may actually affect fossil preservation and erase some crucial information held inside.

Preserving precious specimens

Fossils are rare and fragile by nature. Scientists are constantly evaluating how to balance their impact on fossils with the need to study them.

When palaeontologists and palaeoanthropologists (who work on human fossils) analyse fossils, they want to minimise any potential damage. We want to preserve fossils for future generations as much as possible – and technology can be a huge help here.

Micro-CT works like the medical CT scans doctors use to peek inside the human body. However, it does so at a much smaller scale and at a greater resolution.

This is perfect for studying small objects such as fossils. With micro-CT, scientists can take high-resolution 3D images and access the inner structure of fossils without the need to cut them open.

These scans also allow for virtual copies of the fossils, which other scientists can then access from anywhere in the world. This significantly reduces the risk of damage, since the scanned fossils can safely remain in a museum collection, for example.

Micro-CT is popular and routinely used. The scientific community widely regards it as “non-destructive” because it doesn’t cause any visual damage – but it could still affect the fossil.

How does micro-CT imaging work?

Micro-CT scanning uses X-rays and computer software to produce high-resolution images and reconstruct the fossil specimens in detail. Typically, palaeontologists use commercial scanners for this, but more advanced investigations may use powerful X-ray beams generated at a synchrotron.

The X-rays go through the specimen and are captured by a detector on the other end. This allows for a very fine-grained understanding of the matter they’ve passed through – especially density, which then provides clues about the shape of the internal structures, the composition of the tissues, or any contamination.

The scan produces a succession of 2D images from all angles. Computer software is then used to “clean up” these high-resolution images and assemble them into a 3D shape – a virtual copy of the fossil and its inner structures.

But X-rays are not harmless

X-rays are a type of ionising radiation. This means they have a high level of energy and can break electrons away from atoms (this is called ionisation).

In living tissue, ionising radiation can damage cells and DNA, although the level of damage will depend on the duration and intensity of exposure. X-rays and CT scans used in medicine generally have a very low risk since the exposure of the human body is reduced as much as possible.

However, despite what we know about the impact of X-rays on living cells, the potential impact of X-rays on fossils through micro-CT imaging has never been deeply investigated.

What did our study find?

Using standard settings on a typical micro-CT scanner, we scanned several modern and fossil bones and teeth from animals. We also measured their collagen content before and after scanning.

Collagen is useful for many analytical purposes, such as finding out the age of the fossils using radiocarbon dating, or for stable isotope analysis – a method used to infer the diet of the extinct species, for example. The collagen content in fossils is usually much lower than in modern specimens because it slowly breaks down over time.

After comparing our measurements with unscanned samples taken from the same specimens, we found two things.

First, the radiocarbon age remained unchanged. In other words, micro-CT scanning doesn’t affect radiocarbon dating. That’s the good news.

The bad news is that we did observe a significant decrease in the amount of collagen present. In other words, the micro-CT scanned samples had about 35% less collagen than the samples before scanning.

This shows micro-CT imaging has a non-negligible impact on fossils that contain collagen traces. While this was to be expected, the impact hasn’t been experimentally confirmed before.

It’s possible some fossil samples won’t have enough collagen left after micro-CT scanning. This would make them unsuitable for a range of analytical techniques, including radiocarbon dating.

What now?

In a previous study, we showed micro-CT can artificially “age” fossils later dated with a method called electron spin resonance. It’s commonly used to date fossils older than 50,000 years – beyond what the radiocarbon method can discern.

This previous study and our new work show that micro-CT scanning may significantly and irreversibly change the fossil and the information it holds.

Despite causing no visible damage to the fossil, we argue that in this context the technique should no longer be regarded as non-destructive.

Micro-CT imaging is highly valuable in palaeontology and palaeoanthropology, no doubt about that. But our results suggest it should be used sparingly to minimise how much fossils are exposed to X-rays. There are guidelines scientists can use to minimise damage. Freely sharing data to avoid repeated scans of the same specimen will be helpful, too.

Mathieu Duval receives funding from the Spanish State Research Agency (Agencia Estatal de Investigación). He is currently the recipient of a Ramón y Cajal fellowship (RYC2018-025221-I) funded by MCIN/AEI/10.13039/501100011033 and by ‘‘ESF Investing in your future”. This work is also part of Spanish Grant PID2021-123092NB-C22 funded by MCIN/AEI/10.13039/501100011033/FEDER, UE, and by ‘‘ERDF A way of making Europe”.

Laura Martín-Francés receives funding from Marie Sklodowska-Curie Actions of the EU Ninth programme (2021-2027) under the HORIZON-MSCA-2021-PF-01-Project: 101060482.

– ref. Scientists could be accidentally damaging fossils with a method we thought was safe – https://theconversation.com/scientists-could-be-accidentally-damaging-fossils-with-a-method-we-thought-was-safe-258827

Source: The Conversation – Global Perspectives – By Faisal Hai, Professor and Head of School of Civil, Mining, Environmental and Architectural Engineering, University of Wollongong

The kettle is a household staple practically everywhere – how else would we make our hot drinks?

But is it okay to re-boil water that’s already in the kettle from last time? While bringing water to a boil disinfects it, you may have heard that boiling water more than once will somehow make the water harmful and therefore you should empty the kettle each time.

Such claims are often accompanied by the argument that re-boiled water leads to the accumulation of allegedly hazardous substances including metals such as arsenic, or salts such as nitrates and fluoride.

This isn’t true. To understand why, let’s look at what is in our tap water and what really happens when we boil it.

What’s in our tap water?

Let’s take the example of tap water supplied by Sydney Water, Australia’s largest water utility which supplies water to Sydney, the Blue Mountains and the Illawarra region.

From the publicly available data for the January to March 2025 quarter for the Illawarra region, these were the average water quality results:

• pH was slightly alkaline
• total dissolved solids were low enough to avoid causing scaling in pipes or appliances
• fluoride content was appropriate to improve dental health, and
• it was “soft” water with a total hardness value below 40mg of calcium carbonate per litre.

The water contained trace amounts of metals such as iron and lead, low enough magnesium levels that it can’t be tasted, and sodium levels substantially lower than those in popular soft drinks.

These and all other monitored quality parameters were well within the Australian Drinking Water Guidelines during that period. If you were to make tea with this water, re-boiling would not cause a health problem. Here’s why.

It’s difficult to concentrate such low levels of chemicals

To concentrate substances in the water, you’d need to evaporate some of the liquid while the chemicals stay behind. Water evaporates at any temperature, but the vast majority of evaporation happens at the boiling point – when water turns into steam.

During boiling, some volatile organic compounds might escape into the air, but the amount of the inorganic compounds (such as metals and salts) remains unchanged.

While the concentration of inorganic compounds might increase as drinking water evaporates when boiled, evidence shows it doesn’t happen to such an extent that it would be hazardous.

Let’s say you boil one litre of tap water in a kettle in the morning, and your tap water has a fluoride content of 1mg per litre, which is within the limits of Australian guidelines.

You make a cup of tea taking 200ml of the boiled water. You then make another cup of tea in the afternoon by re-boiling the remaining water.

On both occasions, if heating was stopped soon after boiling started, the loss of water by evaporation would be small, and the fluoride content in each cup of tea would be similar.

But let’s assume that when making the second cup, you let the water keep boiling until 100ml of what’s in the kettle evaporates. Even then, the amount of fluoride you would consume with the second cup (0.23mg) would not be significantly higher than the fluoride you consumed with the first cup of tea (0.20mg).

The same applies to any other minerals or organics the supplied water may have contained. Let’s take lead: the water supplied in the Illawarra region as mentioned above, had a lead concentration of less than 0.0001mg per litre. To reach an unsafe lead concentration (0.01mg per litre, according to Australian guidelines) in a cup of water, you’d need to boil down roughly 20 litres of tap water to just that cup of 200ml.

Practically that is unlikely to happen – most electric kettles are designed to boil briefly before automatically shutting off. As long as the water you’re using is within the guidelines for drinking water, you can’t really concentrate it to harmful levels within your kettle.

But what about taste?

Whether re-boiled water actually affects the taste of your drinks will depend entirely on the specifics of your local water supply and your personal preferences.

The slight change in mineral concentration, or the loss of dissolved oxygen from water during boiling may affect the taste for some people – although there are a lot of other factors that contribute to the taste of your tap water.

The bottom line is that as long as the water in your kettle was originally compliant with guidelines for safe drinking water, it will remain safe and potable even after repeated boiling.

Faisal Hai does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Is it okay to boil water more than once, or should you empty the kettle every time? – https://theconversation.com/is-it-okay-to-boil-water-more-than-once-or-should-you-empty-the-kettle-every-time-260293