Category: Academic Reportage

Source: The Conversation – USA – By Zachary del Rosario, Assistant Professor of Engineering, Olin College of Engineering

Probability underpins AI, cryptography and statistics. However, as the philosopher Bertrand Russell said, “Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.”

I teach statistics to engineers, so I know that while probability is important, it is counterintuitive.

Probability is a branch of mathematics that describes randomness. When scientists describe randomness, they’re describing chance events – like a coin flip – not strange occurrences, like a person dressed as a zebra. While scientists do not have a way to predict strange occurrences, probability does predict long-run behavior – that is, the trends that emerge from many repeated events.

Modeling with probability

Since probability is about events, a scientist must choose which events to study. This choice defines the sample space. When flipping a coin, for example, you might define your event as the way it lands.

Coins almost always land on heads or tails. However, it’s possible – if very unlikely – for a coin to land on its side. So to create a sample space, you’d have two choices: heads and tails, or heads, tails and side. For now, ignore the side landings and use heads and tails as our sample space.

Next, you would assign probabilities to the events. Probability describes the rate of occurrence of an event and takes values between 0% and 100%. For example, a fair flip will tend to land 50% heads up and 50% tails up.

To assign probabilities, however, you need to think carefully about the scenario. What if the person flipping the coin is a cheater? There’s a sneaky technique to “wobble” the coin without flipping, controlling the outcome. Even if you can prevent cheating, real coin flips are slightly more probable to land on their starting face – so if you start the flip with the coin heads up, it’s very slightly more likely to land heads up.

In both the cheating and real flip cases, you need an appropriate sample space: starting face and other face. To have a fair flip in the real world, you’d need an additional step where you randomly – with equal probability – choose the starting face, then flip the coin.

These assumptions add up quickly. To have a fair flip, you had to ignore side landings, assume no one is cheating, and assume the starting face is evenly random. Together, these assumptions constitute a model for the coin flip with random outcomes. Probability tells us about the long-run behavior of a random model. In the case of the coin model, probability describes how many coins land on heads out of many flips.

But instead of using a random model, why not just solve the coin toss using physics? Actually, scientists have done just that, and the physics shows that slight changes in the speed of the flip determine whether it comes up heads or tails. This sensitivity makes a coin flip unpredictable, so a random model is a good one.

Frequency vs. probability

Probability differs from frequency, which is the rate of events in a sequence. For example, if you flip a coin eight times and get two heads, that’s a frequency of 25%. Even if the probability of flipping a coin and seeing heads is 50% over the long run, each short sequence of flips will come out different. Four heads and four tails is the most probable outcome from eight flips, but other events can – and will – happen.

Frequency and probability are the same in one special setting: when the number of data points goes to infinity. In this sense, probability tells us about long-run behavior.

Applications to AI, cryptography and statistics

Probability isn’t just useful for predicting coin flips. It underlies many modern technological systems.

For example, AI systems such as large language models, or LLMs, are based on next-word prediction. Essentially, they compute a probability for the words that follow your prompt. For example, with the prompt “New York” you might get “City” or “State” as the predicted next word, because in the training data those are the words that most frequently follow.

But since probability describes randomness, the outputs of a LLM are random. Just like a sequence of coin flips is not guaranteed to come out the same way every time, if you ask an LLM the same question again, you will tend to get a different response. Effectively, each next word is treated like a new coin flip.

Randomness is also key to cryptography: the science of securing information. Cryptographic communication uses a shared secret, such as a password, to secure information. However, surprising randomness isn’t good enough for security, which is why picking a surprising word is a bad choice of password. A shared secret is only secure if it’s hard to guess. Even if a word is surprising, real words are easier to guess than flipping a “coin” for each letter.

You can make a much stronger password by using probability to choose characters at random on your keyboard – or better yet, use a password manager.

Finally, randomness is key in statistics. Statisticians are responsible for designing and analyzing studies to make use of limited data. This practice is especially important when studying medical treatments, because every data point represents a person’s life.

The gold standard is a randomized controlled trial. Participants are assigned to receive the new treatment or the current standard of care based on a fair coin flip. It may seem strange to do this assignment randomly – using coin flips to make decisions about lives. However, the unpredictability serves an important role, as it ensures that nothing about the person affects their chance to get the treatment: not age, gender, race, income or any other factor. The unpredictability helps scientists ensure that only the treatment causes the observed result and not any other factor.

So what does probability mean? Like any kind of math, it’s only a model, meaning it can’t perfectly describe the world. In the examples discussed, probability is useful for describing long-term behaviors and using unpredictability to solve practical problems.

Zachary del Rosario has received funding from the National Science Foundation and Toyota Research Institute.

– ref. Probability underlies much of the modern world – an engineering professor explains how it actually works – https://theconversation.com/probability-underlies-much-of-the-modern-world-an-engineering-professor-explains-how-it-actually-works-273332

Source: The Conversation – USA – By Richard F. Hamm, Professor of History, University at Albany, State University of New York

As the actions of agents with U.S. Immigration and Customs Enforcement come under intense scrutiny, it’s worth noting that a little more than 100 years ago, another expansion of federal policing – to enforce national Prohibition – also sparked nationwide concern.

As a U.S. history scholar, I know both the government agencies charged with enforcing national Prohibition in the early 20th century and with mass deportation in the early 21st century were hastily expanded. They were asked to achieve difficult objectives and were staffed by sometimes poorly trained people who at times resorted to violence.

National prohibition enforcement

When Congress approved the Volstead Act in 1919 that outlawed the manufacture, sale and transportation of alcoholic liquors, it purposely limited the number of Prohibition enforcement officials due to pressure from powerful dry lobbying groups, which supported the prohibition of alcohol sales and consumption. These groups thought the majority of the Prohibition policing would be done by states.

The Volstead Act also exempted Prohibition agents from civil service laws, which would have required job applicants to pass certain minimum standards. The exemption was written into the law because the prohibitionist lobby only trusted committed “drys” – people resolutely dedicated to maintaining an alcohol-free society – to do the enforcing, and they thought that they would control the appointments.

For the first years of Prohibition, the Bureau of Prohibition belonged to a division of the Bureau of Internal Revenue – some were converted alcohol tax collectors. Then they became part of the Bureau of Prohibition in the Treasury Department. And in 1930, they moved to the Department of Justice.

These moves to various bureaus and departments reflected attempts to curtail corruption, reduce the influence of the prohibitionists on staffing, and increase effectiveness. Despite the moves, funding and training for Prohibition agents never improved. Additionally, in an effort to cut government spending during the Great Depression, the Herbert Hoover administration cut Prohibition agents’ per diem pay from US$6 to $5.

The initial group of Prohibition agents were either committed prohibitionists or “political hacks with little law enforcement experience,” according to author W. J. Rorabaugh. The hacks, Rorabaugh wrote, soon outnumbered the prohibitionists.

In 1927, Federal Circuit Judge William S. Keynon said that “three-fourths of the 2,500 dry agents are ward heelers and sycophants named by the politicians.” The assistant attorney general in charge of Prohibition enforcement, Mabel Walker Willebrandt, said that Prohibition agents were “as devoid of honesty and integrity” as those who violated Prohibition laws.

When Prohibition agents were placed under the civil service, 60% of them failed their civil service tests. In a six-year period beginning in 1920, 752 Prohibition officials lost their jobs for delinquency or misconduct. Drunkenness and bribery were the two main reasons for dismissal.

In 1930, the 1,450 front-line Prohibition agents dwarfed the 350 FBI field agents across the country. They were the largest federal law enforcement body, and they were busy.

From 1921 to 1930, they averaged over a half-million arrests per year. They seized over 45,000 automobiles, and by their own account, Prohibition agents killed 89 people.

However, the Association Against the Prohibition Amendment calculated that about 1,000 people were killed in enforcing Prohibition.

Endemic violence

Federal officials authorized Prohibition agents’ use of violence. One official told U.S. Sen. Wesley Jones, a strong prohibitionist, that some bootleggers “deserve a good killing, and I am not losing any sleep if now and then a bootlegger is killed.”

But Prohibition agents did not just shoot criminals. The Washington Herald detailed in 1929 a pattern of reckless use of force, with prohibition agents shooting at the tires of escaping cars and accidentally firing weapons. In 1924, within blocks of the U.S. Capitol, a Prohibition agent who was firing at a fleeing car carrying a bootlegger accidentally shot Sen. Frank L. Greene of Vermont. Greene, wounded in the head, never fully recovered the use of one arm.

The author Daniel Okrent illustrated the link between trigger-happy officers and shoddy recruitment and training when he detailed the case of “the first agent to kill a suspect bootlegger in the line of duty.” The Prohibition agent had been accepted into service under a false name. He was not a stranger to killing, as he had killed a man when he was 14. He had also served multiple prison terms. Indeed, he was given his badge when “still incarcerated at Dannemora State Prison,” according to Okrent.

The parallels between Prohibition and the Trump administration’s mass deportation tactics are not identical. Prohibition was more unpopular in much of the country compared with mass deportation. And Congress was not willing to adequately pay for Prohibition enforcement, while it has generously funded ICE.

Several reports detail ICE’s recent massive expansion. In early January 2026, the agency announced it grew by 120%, adding 12,000 agents to the existing force of 10,000, which raised concerns among lawmakers about lowered training standards to meet recruitment targets. Other accounts reveal lax vetting, insufficient training and past officer misconduct.

But both efforts share important similarities. They were hastily built, with agents who were asked to do something very difficult, and staffed by sometimes poorly trained people who were authorized to use force.

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

– ref. Enforcing Prohibition with a massive new federal force of poorly trained agents didn’t go so well in the 1920s – https://theconversation.com/enforcing-prohibition-with-a-massive-new-federal-force-of-poorly-trained-agents-didnt-go-so-well-in-the-1920s-276258

Source: The Conversation – USA (2) – By Brian Herman, Vice President for Research, University of Minnesota

Yale University, Columbia University and the University of California, Los Angeles are among the schools that have recently placed professors on leave, seen faculty resign or made other changes over faculty members’ ties to Jeffrey Epstein.

The University of Arizona, for example, canceled a science conference scheduled for April 2026, following the news that several speakers and organizers were named in the Epstein files. Astrobiologist Stuart Hameroff, for example, wrote on the social platform X on Feb. 6, 2026, that he “obtained one-time funding” for a conference from Epstein.

Bard College’s president, Leon Botstein, is among other academic leaders and researchers who have said that they met with Epstein for fundraising purposes – though, as The New York Times reports, Epstein rarely delivered on the money he promised for research and other purposes.

“There is a tremendous drive to acquire money to support the work of faculty and staff. The pressure has always been there – but you can still approach that in an ethically and morally acceptable way,” said Brian Herman, a former vice president for research at the University of Minnesota, in an interview that has been edited for length and clarity.

Amy Lieberman, the education editor at The Conversation U.S., spoke with Herman to understand how philanthropy for colleges and universities works, and what standards and safeguards are in place to help ensure that this money is given in an ethical manner.

How is research at universities typically funded?

Funding to support university research comes from a variety of different sources.

Most university research funding – approximately 53%-55% of that support – comes from the federal government, like the National Institutes of Health and the National Science Foundation.

About 8% of total funding comes from a number of private foundations and nonprofits, like the American Cancer Society.

Universities can also request that state and federal legislators allocate funding in their yearly appropriations bills for research. This involves negotiations between universities and their state and federal legislators. State and local agencies provide about 5% of total university research funding.

Universities themselves fund between 25%-26% of research, and businesses give 6%.

Other sources of funding, including individual donors, account for about 3% of the money that funds university research.

These individuals might be alumni of the university, have another kind of connection to the school or are personally interested in a specific area of expertise of the university. Or, they could be grateful patients who had medical issues solved by the university’s medical school.

How do universities connect with private donors?

Universities typically have fundraising offices that oversee relationships with donors.

Donor and university partnerships involve significant negotiations about how the money will be invested. Universities typically will work with faculty members with expertise in the area of research a donor wants to support and put together a research proposal. The prospective donor then reviews the plan and decides whether they want to support the research.

After universities receive and invest a donation, they give donors a progress report on the investment.

Private donors give money to the university, and not to an individual faculty member. This allows proper accounting and controls on how the money is used, to make sure they support the intended research and adhere to university policies.

How do universities screen donors for conflicts of interest, for example?

All universities have compliance offices that set up a compendium of policies that guide how they accept private funding.

The schools try to make sure there is no financial conflict of interest for the donor, researcher or institution – or a conflict of interest between people performing the research and those providing the funding.

There is practically always a need to strike a balance between managing potential conflicts appropriately and being able to obtain the resources necessary for a university to conduct its work.

Do universities typically screen for donors who have committed a crime?

Most universities screen potential donors.

The larger the dollar amount in question, the more substantive the screening is. Many universities have policies on this issue. It is likely that universities will strengthen these policies based on recent events related to the Epstein case. They will want to become more stringent with screening to make sure that their donors are not morally compromised.

For example, universities can conduct background checks on potential donors.

But if the donation is small, it is possible that a university would not conduct a background check. So, a faculty member could seek $5,000 for a conference and approach a donor individually and not involve the rest of the university in the donation.

How could the Epstein case influence how universities screen donors?

I expect that universities will enact more policies and procedures that guard against a situation like what we are seeing in the Epstein files. Universities may require more substantive checks on all donations independent of size and source. They are also likely to carry out more training of faculty, staff and administrators on how to secure individual donor support.

If universities have not already done so, I think they should instruct faculty members not to directly contact a donor or legislator on behalf of the university. They should also increase the penalties for university employees who do not comply with this policy.

In some cases, researchers may have an idea that is not aligned strategically with how the university is raising philanthropic funds. They may go looking for their own money. This doesn’t happen a lot, but it does happen, and universities will have to become more vigilant about these types of situations.

In reality, money is necessary to do most everything at universities, including paying faculty and staff, purchasing research supplies and even keeping the lights on in the research labs. Money is also a metric that is used as a measure of success and the ranking of a university – meaning, getting more money can lead to a higher ranking.

University leaders are facing natural pressure to raise money. There is a tremendous drive to acquire money to support the work of faculty and staff. This can create significant pressure to acquire funding – but this must always be done in an ethically and morally appropriate way.

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

– ref. Individual donors provide only a small slice of university research funding – but Jeffrey Epstein’s ties with academics show why screening matters – https://theconversation.com/individual-donors-provide-only-a-small-slice-of-university-research-funding-but-jeffrey-epsteins-ties-with-academics-show-why-screening-matters-276345

Source: The Conversation – USA (2) – By Stanley Stepanic, Assistant Professor of Slavic Languages and Literatures, University of Virginia

The Lord of Vampires. The King of the Undead. The Ultimate Lover. All refer to the immortal Count Dracula, who originally appeared in Bram Stoker’s 1897 novel.

Yet the character’s fame has sprung more from his 200-plus cinematic resurrections, beginning with “Dracula’s Death” in 1921 and, most recently, in Luc Besson’s “Dracula,” which premiered in the U.S. in February 2026.

Besson’s rendition has received particular attention for its focus on personal passion. Originally titled “Dracula: A Love Tale,” the film features a protagonist who is not simply a monster, but a lover. The New York Times called the movie “extravagantly silly” and described actor Caleb Landry Jones’ performance of the classic monster as “deliciously operatic: less villain, more virtuoso in love.”

Meanwhile, in London, Dracula as lover also features as a theme in Cynthia Erivo’s new West End production, in which she plays the Count and 22 other characters. A smaller, recent production out of Washington, D.C., titled “Dracula: A Comedy of Terrors” presents the Count similarly, though with a hilariously deviant LGBTQ+ bite.

In other words, Dracula has come a long way from his days as a lecherous, old creep, a shift that can be attributed, in part, to evolving attitudes on love, gender and sexuality.

‘Even his breath was rank’

When Stoker first published “Dracula,” the character appeared at the end of a long line of literary vampires, from Lord Ruthven in John Polidori’s “The Vampyre” (1819) to Sir Francis Varney in “Varney the Vampire” (1845-1847).

These vampires were all decrepit, revolting and predatory old men, and Stoker’s Count Dracula was no different. In the novel, one character notes Dracula’s “course” hands, the “extraordinary pallor” of his skin and his “extremely pointed” ears; atop his “lofty domed forehead,” his hair grew “scantily” upon his head. Even his “breath was rank.”

Another character describes Dracula as possessing “not a good face,” adding that it was “hard, and cruel.”

The first surviving feature-length film adaptation of “Dracula” was the 1922 German film “Nosferatu: A Symphony of Horror,” which cribs the plot and characters from Stoker’s novel. In it, Count Orlok – essentially a bootleg version of Dracula – looks ratlike, emaciated and pallid.

Seduction game

Little about Stoker’s Dracula or Count Orlok screamed “lover,” though there’s arguably an implicit sexuality in the way he attacks and stalks his victims.

Instead, Dracula gained his “lover” label from later appearances on screen.

The earliest example appears in the 1944 film “House of Frankenstein,” where Rita (Anne Gwynne) is initially concerned by Dracula’s presence. Later, however, she finds herself “no longer afraid” after he places a ring onto her index finger, which magically fits to her precise shape.

At the end of this scene, as she longingly looks into his eyes, he announces he will come for her the next day, as if it were all a budding tryst.

The evolution of Dracula’s character mirrored changes in more general perceptions of gender, sexuality and violence that occurred after World War II, when popular culture started to chip away at the centrality of the nuclear family. As books, films and TV shows explored themes like lust, infidelity, same-sex relationships and divorce, images of vampires became more complex.

In the 1958 film “Dracula,” for example – titled “Horror of Dracula” in the U.S. – Dracula (Christopher Lee) is a predator who breaks into the homes of married women.

Yet there’s also a hint of romance. In one particular scene, he assaults Mina Holmwood (Melissa Stribling). But Mina appears to eventually give in, and they share a brief, passionate kiss. The British Board of Film Classification even censored the scene, seeing it as a step too far in a film already replete with sexual overtones.

Director Terence Fisher later recalled telling Stribling to depict her character as though she “had one whale of a sexual night, the one of your whole sexual experience. Give me that in your face!”

Lover or monster?

By the 1970s, sexuality became even more of a pronounced theme in vampire-related media, mirroring broader cultural changes in views of human sexuality.

Comic books such as “Vampirella” presented the vampire as a hypersexualized, feminine, erotic symbol of power, while films such as “The Vampire Lovers” explored themes like lesbianism, though not in a way that was entirely explicit.

In the film “Count Dracula’s Great Love” (1973), Dracula falls head over heels for a young girl named Karen, who ends up rejecting his advances. Near the end of the film, the lovesick vampire bemoans, “For the first time, love brings a finish to the life of Dracula,” before driving a stake into his heart with his own hands.

Shortly thereafter, a made-for-TV “Dracula” features Dracula’s search for his dead wife.

The “search for a dead lover” would become a central theme in future films. For example, in Francis Ford Coppola’s “Bram Stoker’s Dracula” (1992), viewers learn that Dracula leaves Transylvania for England to pursue a reincarnation of his dead wife.

This yearning was a borrowed concept. In the Gothic soap opera “Dark Shadows” (1966-1971), the character Barnabas Collins (Jonathan Frid) tries to replicate his romance with his long-dead lover, Josette, by attempting to supernaturally control the living body of a girl named Maggie Evans (Kathryn Leigh Scott) so that she mimics Josette.

The concept of a vampire pining for a lost love – especially one from a lost era – marked a significant evolution in vampire media.

In the 1970s comic book series “The Tomb of Dracula,” the Count has a human wife named Domini; through magical means, he’s even able to conceive a child with her. Thanks to his romance, he can now “understand things such as peace and rest and love.”

Despite Dracula-as-lover now being such a well-worn trope, the ever-adaptable Count is also ready for his traditional scare duties, most recently in Robert Egger’s “Nosferatu” (2024). Whether he’s a lover, a monster or both, Dracula represents the idea of the vampire as a mirror of human experience. Romance can sometimes teeter between love and pain. Passion can sometimes be scary. So when you next see him on stage or screen, don’t be surprised if his fervent love also comes with a sharp bite.

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

– ref. How Dracula became a red-hot lover – https://theconversation.com/how-dracula-became-a-red-hot-lover-275789

Source: The Conversation – USA (3) – By Jenni Shearston, Assistant Professor of Integrative Physiology, University of Colorado Boulder

About half of the global population menstruates at some point in their lives. Disposable products, such as tampons and pads, are some of the most popular products used around the globe to manage menstrual flow.

Unfortunately, studies have shown that many personal care products, including shampoo, lotion, nail polish and menstrual products, contain hazardous chemicals. Items used in or near the vagina are of particular concern because they are in contact with vaginal mucous membranes – the moist tissue lining the inside of the vagina that secretes mucus. These tissues can absorb some chemicals very efficiently.

People use menstrual products 24 hours a day for multiple days monthly, over the course of many years. Tampons, which are used internally, are surrounded by the permeable vaginal mucous membrane for up to eight hours at a time.

I am an environmental epidemiologist, and I study chemical exposure, its sources and its health effects. As a person who menstruates, I also must make my own decisions around menstrual products and manage the challenge of finding accurate information about women’s health risks, which receive less research attention and funding than men’s health.

In 2024, I co-authored the first paper that detected metals in tampons, including toxic metals like lead and arsenic. My colleagues and I also wrote a review paper that surveyed the scientific literature and found about two dozen studies measuring chemicals in menstrual products.

The various chemicals that these studies detected were typically at concentrations low enough to make their health impact unclear. However, they included chemicals known to disrupt the endocrine system, which makes and controls hormones that are essential for bodies to function.

How contaminants get into menstrual products

The first modern tampon in the U.S. was patented in 1931. Nearly a century later, tampons still are made primarily from cotton, rayon or a blend of the two.

Chemicals may get into tampons and other menstrual products in a number of ways. Some chemicals, like heavy metals, are present in soil, either naturally or due to pollution, and may be absorbed by cotton plants.

Other chemicals, such as zinc, may be intentionally added to menstrual products to prevent the growth of harmful bacteria. Still others, such as phthalates – synthetic chemicals used to manufacture plastics – may leach into menstrual products from plastic packaging or be added as part of a fragrance.

Research suggests that these chemicals are present in a large proportion of menstrual products – we found lead present in all 30 tampons we tested. What we don’t yet know is if these chemicals can get into people’s bodies in a high enough concentration to cause health effects in either the reproductive system or elsewhere in the body.

Limited federal regulations

The U.S. Food and Drug Administration regulates tampons, menstrual cups and scented menstrual pads as Class II medical devices, which carry moderate to medium risk. Unscented menstrual pads are Class I medical devices, which are considered low-risk. These categories are based on the risk the device may present to a consumer who uses it in the intended way.

FDA guidance for Class II devices offers only a few general guidelines with respect to chemicals. For menstrual tampons and pads, it recommends – but does not require – that products should not contain two specific dioxin products or “any pesticide and herbicide residues.” Dioxins are a chemical by-product of the bleaching process to whiten cotton, and they are associated with cancer and endocrine disruption. Using non-chlorine bleaching methods can reduce dioxin formation.

The most stringent regulation of tampons in the U.S. occurred after an illness called toxic shock syndrome became a public concern in the 1970s and 1980s. Menstrual toxic shock syndrome occurs when the bacteria Staphlococcus aureus grows in the vagina on inserted menstrual products and releases a toxin called TSST-1. This substance can be absorbed through the vaginal mucosa and cause a variety of symptoms, including fever, high blood pressure, shock and even death.

During this epidemic, in which at least 52 cases were recorded and seven people died over a period of eight months, tampons were associated with the syndrome – especially a highly absorbent tampon called Rely, which was pulled from the market.

In response, the FDA created a task force that recommended standardizing the tampon absorbencies and advised consumers to use the lowest absorbency for their flow. This is why tampons in the U.S. now come in a range of absorbencies, from light through regular to super and ultra, so that users can choose the level they need while minimizing risk of toxic shock.

Living in a ‘soup of chemicals’

Just because a chemical is present in a menstrual product doesn’t mean it can get into the body. However, chemicals like lead and arsenic are known threats to human health. So it’s important to study whether harmful chemicals present in menstrual products could contribute to health problems.

Humans in the modern world live in what expert toxicologist Linda Birnbaum, former director of the National Institute of Environmental Health Sciences, calls a “soup of chemicals.” Simply being present on Earth means being exposed to many chemicals, at different concentrations, all at once. This makes it difficult to unravel the relationship between a single chemical exposure and health.

Nonetheless, science has shown that chemical exposure from at least one menstrual product – vaginal douches – does affect health. Vaginal douching is the process of washing or cleaning the inside of the vagina with water or other fluids.

The American College of Obstetricians and Gynecologists recommends avoiding this process, which can harm healthy bacteria in the vagina, increasing the risk of vaginal infections and other diseases.

In addition, a 2015 study found that women who use vaginal douches have higher concentrations of a chemical called monoethyl phthalate in their urine. Exposure to this substance is associated with reproductive health problems, such as reduced fertility and increased pregnancy risk.

Can these chemicals be absorbed?

Scientists are working now to determine what concentrations of metals and other chemicals can leach out of tampons and other menstrual products. One 2025 study estimated that volatile organic compounds, a group of chemicals that vaporize quickly, can be absorbed through the vaginal mucosa. Volatile organic compounds may be added to menstrual products as part of fragrances, adhesives or other product components.

My team and I are now shifting our focus to the relationship between menstrual product use, various chemicals, and menstrual pain and bleeding severity. We want to see whether some chemicals will be elevated in menstrual blood, whether these chemical levels are higher in people who use tampons, and whether the chemicals are associated with greater menstrual pain and bleeding.

States are starting to act on this issue. For example, in 2024, Vermont became the first U.S. state to ban multiple chemicals from disposable menstrual products. California bans PFAS, a widely used group of highly persistent chemicals, from menstrual products. New York adopted a law in December 2025 barring multiple toxic chemicals from menstrual products.

California also enacted a law in October 2025 that requires manufacturers of disposable tampons and pads to measure concentrations of arsenic, cadmium, lead and zinc in their products, and to share those measurements with the state, which can publish them. More information like this will help support informed choices for millions of consumers who rely on menstrual products every month.

Jenni Shearston receives funding from the United States National Institutes of Health.

– ref. Menstrual pads and tampons can contain toxic substances – here’s what to know about this emerging health issue – https://theconversation.com/menstrual-pads-and-tampons-can-contain-toxic-substances-heres-what-to-know-about-this-emerging-health-issue-268470

Source: The Conversation – USA (3) – By Jan Lowery, Professor of Epidemiology, Colorado School of Public Health, University of Colorado Anschutz Medical Campus

In Colorado, as of 2025, about 500 people a year die from lung cancer as the result of radon gas exposure. Nationally, the number of lung cancer deaths attributed to radon is about 21,000 per year.

Radon is present nearly everywhere outdoors, yet typically at levels that are not harmful. It becomes dangerous when it gets trapped and accumulates inside homes, schools and other buildings.

Radon is a naturally occurring radioactive gas that is produced by the breakdown of uranium, a heavy metal present in the soil. People cannot smell it or see it, which makes radon particularly dangerous. When radon gas forms in the soil, it rises and finds its way into homes old and new through cracked foundations, gaps around sump pumps and drains, and crawl spaces.

Many people are unaware of the radon levels in their home. In Colorado, it is estimated that only 50% of homes have been tested. Thus, many Coloradans may be exposed to elevated radon levels and not know it.

Though tobacco use is the most significant risk factor for lung cancer, accounting for approximately 86% of all lung cancer cases, radon is the leading cause of lung cancer among people who have never used tobacco. Radon also has a compounding effect with tobacco that further increases lung cancer risk among tobacco users. About 7 in 1,000 nontobacco users with prolonged exposure to elevated radon levels may develop lung cancer in their lifetime.

Exposure to radon is preventable. As a cancer epidemiologist, I aim to help all Colorado residents be aware of their home’s radon level and take appropriate actions to mitigate exposure and reduce their and their family’s risk of lung cancer.

Radon in your home

Because of Colorado’s unique geology, including mountainous regions that consist heavily of granite rock that contains uranium, radon levels are higher in Colorado than in other states.

Colorado is among the top 10 states with the highest radon levels across the country. About 50% of Colorado homes tested for radon have levels higher than the recommended threshold set by the Environmental Protection Agency, which is 4 picocuries per liter (pCi/L). The average level of radon in Colorado homes is 6.4 pCi/L, which is equivalent to having 200 chest X-rays each year. Radon levels differ across the 64 counties in Colorado based on their geography and makeup of the soil.

If a home is not adequately vented, radon can build up indoors. When radon decays, it releases radioactive particles that, once inhaled, can damage lung cells. More specifically, these particles can break chemical bonds in the cell’s DNA that, if not repaired, can lead to cancer. Prolonged exposure to high levels of radon, over several years, can cause lung cancer. Similar to tobacco use, it is the cumulative exposure to radon that increases risk for cancer.

Fortunately, there are ways to prevent radon from entering and accumulating inside our homes. Radon mitigation systems use fans and pipes to pull radon gas from below the foundation of the home and vent it outside. These systems can reduce radon levels inside the home by up to 99%.

Know your risk: Testing and mitigating

Testing your home for radon is simple and relatively inexpensive. Test kits are placed in the lowest living area of your house, apartment, condominium or townhome and left for a period of time. The EPA recommends testing for all residential units below the third floor.

There are short-term tests, which take from two to 90 days, and long-term tests, which take 90 days or more. Long-term tests are more accurate for estimating annual average radon levels. Once complete, tests can be mailed directly to a lab for processing.

Test kits typically cost less than US$50 or may be obtained for free from many sources, including the University of Colorado Anschutz Cancer Center. As of February 2026, the cancer center has distributed more than 1,600 test kits to people in 55 Colorado counties. Nearly 40% of the tests distributed thus far show radon levels above the EPA threshold.

The EPA recommends testing over multiple months, including colder months when windows and doors to the outside are typically closed and radon can become trapped indoors. Testing over several months provides a better understanding of the average annual radon level in the home.

Reduce your risk: Radon mitigation

People with radon levels in their home that are at or above 4 pCi/L are recommended to seek mitigation measures. This may involve sealing cracks in basement walls and foundations and installing a fan and vent pipe to pull radon gas from underneath the home and vent it outside. Mitigation can cost between $1,000 and $3,000 depending on home structure and location.

There are resources available for people who need radon mitigation and can’t afford it. Colorado’s state health department has a low-income radon mitigation assistance program that can pay for radon mitigation for people who are eligible based on income requirements.

Radon may be invisible, but its impact on human health is unmistakably real – and largely preventable. By taking action today – testing your home, sharing this knowledge and seeking help when needed – you are investing in a healthier future for yourself and your community.

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

– ref. Colorado has high levels of radon, which can cause lung cancer – here’s how to lower your risk – https://theconversation.com/colorado-has-high-levels-of-radon-which-can-cause-lung-cancer-heres-how-to-lower-your-risk-273666