Latest news with #radioactivity
Al Arabiya
a day ago
- Health
- Al Arabiya
US recalls shrimp sold in Walmart over potential radioactivity scare
US health authorities announced Tuesday a recall of frozen shrimp potentially contaminated with radioactivity. The seafood imported from a company in Indonesia has been marketed in 13 states by retail giant Walmart, the Food and Drug Administration (FDA) said on its website. The recall follows the detection of the radioactive isotope Cesium 137 in shrimp imported through the company called PT. Bahari Makmur Sejati, the advisory said. The level of radioactivity detected was minimal and the product would not pose 'an acute hazard' to consumers, the FDA said. No shrimp imported by the company and stocked for sale in US stores has tested positive for radioactivity, the agency said. But shrimp from the firm 'appears to have been prepared, packed, or held under insanitary conditions whereby it may have become contaminated with Cs-137 and may pose a safety concern.' Over the long term, even low-dose Cesium exposure is linked to an elevated risk of cancer, it added. The FDA asked Walmart to stage a recall of the shrimp and urged people who already bought the product to throw it away.
Yahoo
a day ago
- Health
- Yahoo
Raw Shrimp Sold at Walmart Recalled for Possible Radioactivity
The recall comes after one lot of the shrimp was determined to have low levels of Cs-137, a radioactive isotope NEED TO KNOW Shrimp sold at Walmart is being recalled for possible radioactivity The recall comes after one lot of the shrimp, provided by an Indonesian supplier, was determined to have low levels of Cs-137, a radioactive isotope While the amount of Cs-137 present in the affected lot would not cause immediate harm, the FDA's primary concern is for prolonged, low-dose exposure, which could cause cancer Raw shrimp sold at Walmart is being recalled. The grocery store chain issued a recall of three lots of frozen raw shrimp, the U.S. Food and Drug Administration shared in an announcement. The recall comes after one lot of the shrimp, imported from an Indonesian supplier, was found to contain Cs-137, a radioactive isotope with a half life of about 30 years. The FDA is now working with businesses in the U.S. that sell or distribute products from the supplier, PT. Bahari Makmur Sejati (known through its business name, BMS Foods), who received items after the date Cs-137 was first detected. The recall extends to lots sold in Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Missouri, Mississippi, Ohio, Oklahoma, Pennsylvania, Texas and West Virginia. While the levels of Cs-137 detected in the single lot of frozen raw shrimp are classified below the FDA's Derived Intervention Level — and thus is not immediately hazardous to those who consume it — the organization stated its primary concern is for repeated, low-dose exposure. Prolonged consumption of Cs-137 correlates with a higher risk of cancer, as it can damage DNA in living body cells. The recalled product is Walmart's Great Value brand frozen raw shrimp, with a best by date of 3/15/27. The recalled product will feature lot codes 8005540-1, 8005538-1 or 8005539-1. Never miss a story — sign up for to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories. The FDA found BMS Foods to be in violation of the Federal Food, Drug, & Cosmetic Act, as the product appears to have been processed in unsanitary conditions. The supplier has been added to a new import alert for chemical contamination, so as to prevent further products from BMS Foods from entering U.S. commerce until necessary improvements have been made. An FDA investigation into the supplier is ongoing. Read the original article on People
Sustainability Times
11-08-2025
- Science
- Sustainability Times
'Boars Glow Like 100 Suns': Chernobyl's Radioactive Wild Boars Hold Shocking Secrets Beyond Nuclear Disaster, Challenging Scientific Assumptions Worldwide
IN A NUTSHELL 🔍 Scientists investigate the persistent radioactivity of wild boars in the Chernobyl region, uncovering unexpected sources. of wild boars in the Chernobyl region, uncovering unexpected sources. 🌍 The study reveals that Cold War-era nuclear tests significantly contribute to radiation levels in Europe. significantly contribute to radiation levels in Europe. 🧪 Wild boars remain key to understanding the complex long-term effects of nuclear contamination. of nuclear contamination. 🌳 Chernobyl's forests serve as a living laboratory for studying the environmental legacy of nuclear events. In the aftermath of the Chernobyl disaster, scientists and observers have long been puzzled by the persistent radioactivity of wild boars in the region. While other animal species have gradually recovered, these boars remain strikingly contaminated. Surprisingly, recent findings suggest that the infamous 1986 explosion is not the sole contributor to this phenomenon. Instead, attention has shifted to historical sources of radiation that continue to impact the environment. This revelation underscores the complexity of the radioactivity landscape in and around Chernobyl, turning the region into a living laboratory for understanding long-term nuclear effects. Unraveling the Mystery of Radioactive Boars The resilience of wild boars in the Chernobyl exclusion zone has baffled scientists for decades. Unlike other species whose contamination levels have decreased, these boars show persistent radioactivity. Researchers have focused on cesium-137, a highly contaminating isotope with a half-life of about 30 years. Given this, one would expect a significant reduction in contamination over time. However, the boars' contamination remains stubbornly high, raising questions about the factors at play. Initially, the blame was placed on the exclusion zone's high contamination levels. Yet, a recent study challenges this assumption, suggesting that other historical sources may contribute to the radiation levels found in these boars. This revelation not only shifts the focus from Chernobyl but also highlights the enduring impact of past nuclear activities on the environment. Scientists Stunned as Peacocks Found to Shoot 'Deadly Lasers' From Tails in Shocking Discovery That Could Change Everything About Nature The Overlooked Source of Radiation A surprising discovery has brought attention to another cesium isotope, cesium-135. Unlike cesium-137, this isotope is not primarily from the Chernobyl accident. Research has shown that a significant portion of cesium-135 found in wild boars originates from nuclear tests conducted during the Cold War. These atmospheric tests, carried out in the 1950s and 1960s, contributed to the widespread dispersal of radioactive material across Europe. It is estimated that nearly 70% of the cesium-135 measured today in Europe is a remnant of these nuclear tests, rather than the Chernobyl disaster. This finding not only provides a new perspective on the origins of radioactivity in wild boars but also highlights the long-lasting environmental legacy of nuclear testing. The research underscores the importance of considering multiple sources of contamination when assessing the impact of nuclear activities. 'Everyone Would Starve Except the Rich': This Nightmare Nuclear War Scenario Could Kill Crops and Collapse Civilization in Just Months Implications for Environmental Science The persistence of radioactivity in Chernobyl's wild boars offers valuable insights into the long-term effects of nuclear contamination. The discovery that Cold War-era nuclear tests contribute significantly to current radiation levels in these animals challenges previous assumptions. It emphasizes the need for a broader perspective when examining the environmental consequences of nuclear events. This finding has implications beyond Chernobyl, as it suggests that historical nuclear activities continue to affect ecosystems worldwide. Understanding the interplay between different sources of radiation can inform future policy decisions and environmental management strategies. It also highlights the importance of ongoing research to fully comprehend the complex dynamics of nuclear contamination and its impact on biodiversity. Rolls-Royce's 'Nuclear Plan Could Light Up 3 Million US Homes but Puts Safety at Risk,' Igniting Explosive National Controversy The Future of Chernobyl's Living Laboratory The forests surrounding Chernobyl remain a unique research site for studying the effects of nuclear contamination. The area's wildlife, particularly the resilient wild boars, serves as a critical indicator of the long-term impacts of radiation. As scientists continue to explore the origins and consequences of contamination, new revelations may emerge, offering deeper insights into the environmental and biological dynamics at play. Moving forward, the challenge lies in addressing the lingering effects of both Chernobyl and historical nuclear tests. How can we mitigate the impact of past nuclear activities on the environment and ensure the safety and sustainability of affected ecosystems? The answers to these questions will shape our understanding of nuclear legacy and guide future efforts to protect our planet's natural heritage. The enduring radioactivity in Chernobyl's wild boars serves as a stark reminder of the complex legacy of nuclear activities. As researchers continue to unravel the mysteries of this contamination, they are faced with broader questions about the long-term environmental impacts of nuclear events. What steps should be taken to address the ongoing effects of historical nuclear tests, and how can we better protect our ecosystems from future contamination? This article is based on verified sources and supported by editorial technologies. Did you like it? 4.5/5 (27)
Yahoo
24-06-2025
- Business
- Yahoo
F3 - Hits Radioactivity in 32m Step Out - Extending Zone at Broach Lake
Mobilizes Sonic Drill to Tetra Zone Kelowna, British Columbia--(Newsfile Corp. - June 24, 2025) - F3 Uranium Corp. (TSXV: FUU) (OTCQB: FUUFF) ("F3" or "the Company") is pleased to announce strike growth of the radioactivity at the PW Area on the Broach Property — now named the Tetra Zone with PLN25-210 which intersected a total of 21.0m composite radioactivity in a 32m step-out along strike to the northwest from discovery hole PLN25-205 which intersected radioactivity over a total of 33.0m including 0.56m of high radioactivity (>10,000 cps) with a peak of 37,700 cps at 398.34m (see NR April 15, 2025). The Tetra Zone remains open in both directions and drilling is continuing. Geophysical and structural modeling of the Tetra Zone is advancing, and F3 is now mobilizing an LS600 Sonic drill to the Zone; this will improve the pace of overburden casing and increase targeting accuracy — a technique deployed successfully at the JR Zone during delineation drilling. 2025 Handheld Spectrometer Highlights: Broach Lake: Tetra ZonePLN25-210 (line 11280S): 0.5m interval with radioactivity of 700 cps between 165.0 and 165.5m, and 0.5m interval with radioactivity of 450 cps between 308.0 and 308.5m, and 0.5m interval with radioactivity of 690 cps between 332.0 and 332.5m, and 2.0m interval with radioactivity of 340 cps between 349.0 and 351.0m, and 3.0m interval with radioactivity of 1,500 cps between 354.5 and 357.5m, and 0.5m interval with radioactivity of 920 cps between 364.0 and 364.5m, and 3.5m interval with radioactivity of 900 cps between 367.5 and 371.0m, and 3.5m interval with radioactivity of 1,200 cps between 380.0 and 383.5m, and 7.0m interval with radioactivity of 2,600 cps between 388.5 and 395.5m Sam Hartmann, Vice President Exploration, commented: "Bringing a Sonic drill back to site will allow us to more efficiently define, delineate and expand the highly radioactive core seen in PLN25-205. PLN25-210 represents a 32m step out grid west and validated our geological and structural models, which will be used for further along strike drilling. The sonic drill will help reduce drill trace deviation as seen in PLN25-207 and allow for intersection of the target areas exactly where intended. Assays from the discovery hole PLN25-205 are being rushed and the results will be released once complete and reviewed. Overall, we are very encouraged by the geology in these initial drill holes at Tetra, which is currently the best exploration target in the F3 portfolio." Map 1. Tetra Zone at Broach Lake Property -2025 Scintillometer Results To view an enhanced version of this graphic, please visit: Image 1. Cross Section Line 11280S To view an enhanced version of this graphic, please visit: Table 1. Drill Hole Summary and Handheld Spectrometer Results Collar Information * Hand-held Spectrometer Results On Mineralized Drillcore (>300 cps / >0.5m minimum) Athabasca Unconformity Depth (m) Total Drillhole Depth(m) Hole ID SectionLine Easting Northing Elevation Az Dip From(m) To (m) Interval(m) MaxCPS PLN25-205 11310S 589327 6397941 583 46 -65 647.50 648.00 0.50 340 168.8 725663.00 663.50 0.50 330 PLN25-206 11325S 589315 6397929 584 48 -65 317.50 318.00 0.50 330 161.9 740318.00 318.50 0.50 350 PLN25-207 11505S 589481 6397809 587 46 -66 280.00 280.50 0.50 480 154.4 674280.50 281.00 0.50 320621.00 621.50 0.50 1200 PLN25-208 11205S 589824 6398440 576 43 -70 162.50 163.00 0.50 320 165.7 623 PLN25-209 11280S hole abandoned; no radioactivity >300 cps 180.3 221 PLN25-209A 11280S 589343 6397999 583 47 -71 329.50 330.00 0.50 400 182.0 488 PLN25-210 11280S 589341 6397997 583 47 -73 165.00 165.50 0.50 700 166.1 527308.00 308.50 0.50 450332.00 332.50 0.50 690349.00 349.50 0.50 300350.50 351.00 0.50 340354.50 355.00 0.50 520355.50 356.00 0.50 1100356.00 356.50 0.50 570357.00 357.50 0.50 1500364.00 364.50 0.50 920367.50 368.00 0.50 900369.50 370.00 0.50 720370.50 371.00 0.50 320380.00 380.50 0.50 310380.50 381.00 0.50 330382.50 383.00 0.50 1200383.00 383.50 0.50 390388.50 389.00 0.50 1100389.00 389.50 0.50 570389.50 390.00 0.50 1400390.00 390.50 0.50 600390.50 391.00 0.50 410391.50 392.00 0.50 810392.00 392.50 0.50 2500392.50 393.00 0.50 2100393.00 393.50 0.50 2600393.50 394.00 0.50 1300394.00 394.50 0.50 760395.00 395.50 0.50 460 Handheld spectrometer composite parameters:1: Minimum Thickness of 0.5m2: CPS Cut-Off of 300 counts per second3: Maximum Internal Dilution of 2.0m The natural gamma radiation detected in the drill core, as detailed in this news release, was measured in counts per second (cps) using a handheld Radiation Solutions RS-125 spectrometer which has been calibrated by Radiation Solutions Inc. The Company designates readings exceeding 300 cps on the handheld spectrometer (occasionally referred to as a scintillometer in industry parlance; this colloquial usage stems from historical naming conventions and the shared functionality of detecting gamma radiation a scintillometer)-as "anomalous", readings above 10,000 cps as "highly radioactive", and readings surpassing 65,535 cps as "off-scale". However, readers are cautioned that spectrometer or scintillometer measurements often do not directly or consistently correlate with the uranium grades of the rock samples and should be regarded solely as a preliminary indicator of the presence of radioactive materials. Samples from the drill core are split into half sections on site. Where possible, samples are standardized at 0.5m down-hole intervals. One-half of the split sample is sent to SRC Geoanalytical Laboratories (an SCC ISO/IEC 17025: 2005 Accredited Facility) in Saskatoon, SK while the other half remains on site for reference. Analysis includes a 63 element suite including boron by ICP-OES, uranium by ICP-MS and gold analysis by ICP-OES and/or AAS. The Company considers uranium mineralization with assay results of greater than 1.0 weight % U3O8 as "high grade" and results greater than 20.0 weight % U3O8 as "ultra-high grade". All depth measurements reported are down-hole and true thicknesses are yet to be determined. About the Patterson Lake North Project: The Company's 42,961-hectare 100% owned Patterson Lake North Project (PLN) is located just within the south-western edge of the Athabasca Basin in proximity to Paladin's Triple R and NexGen Energy's Arrow high-grade uranium deposits, an area poised to become the next major area of development for new uranium operations in northern Saskatchewan. The PLN Project consists of the 4,074-hectare Patterson Lake North Property hosting the JR Zone Uranium discovery approximately 23km northwest of Paladin's Triple R deposit, the 19,864-hectare Minto Property, and the 19,022-hectare Broach Property hosting the Tetra Zone, F4's newest discovery 13km south of the JR Zone. All three properties comprising the PLN Project are accessed by Provincial Highway 955. Qualified Person: The technical information in this news release has been prepared in accordance with the Canadian regulatory requirements set out in National Instrument 43-101 and approved on behalf of the company by Raymond Ashley, President & COO of F3 Uranium Corp, a Qualified Person. Mr. Ashley has reviewed and approved the data disclosed. About F3 Uranium Corp.: F3 Uranium is a uranium exploration company, focusing on the recently discovered high-grade JR Zone on its Patterson Lake North (PLN) Project in the Western Athabasca Basin. F3 Uranium currently has 3 properties in the Athabasca Basin: Patterson Lake North, Minto, and Broach. The western side of the Athabasca Basin, Saskatchewan, is home to some of the world's largest high grade uranium deposits including Paladin's Triple R and Nexgen's Arrow. Forward-Looking Statements This news release contains certain forward-looking statements within the meaning of applicable securities laws. All statements that are not historical facts, including without limitation, statements regarding future estimates, plans, programs, forecasts, projections, objectives, assumptions, expectations or beliefs of future performance, including statements regarding the suitability of the Properties for mining exploration, future payments, issuance of shares and work commitment funds, entry into of a definitive option agreement respecting the Properties, are "forward-looking statements." These forward-looking statements reflect the expectations or beliefs of management of the Company based on information currently available to it. Forward-looking statements are subject to a number of risks and uncertainties, including those detailed from time to time in filings made by the Company with securities regulatory authorities, which may cause actual outcomes to differ materially from those discussed in the forward-looking statements. These factors should be considered carefully and readers are cautioned not to place undue reliance on such forward-looking statements. The forward-looking statements and information contained in this news release are made as of the date hereof and the Company undertakes no obligation to update publicly or revise any forward-looking statements or information, whether as a result of new information, future events or otherwise, unless so required by applicable securities laws. The TSX Venture Exchange and the Canadian Securities Exchange have not reviewed, approved or disapproved the contents of this press release, and do not accept responsibility for the adequacy or accuracy of this release. F3 Uranium Corp.750-1620 Dickson AvenueKelowna, BC V1Y9Y2 Contact InformationInvestor RelationsTelephone: 778 484 8030Email: ir@ ON BEHALF OF THE BOARD"Dev Randhawa"Dev Randhawa, CEO To view the source version of this press release, please visit Error in retrieving data Sign in to access your portfolio Error in retrieving data Error in retrieving data Error in retrieving data Error in retrieving data
BBC News
10-06-2025
- Science
- BBC News
The hunt for Marie Curie's radioactive fingerprints in Paris
Marie Curie worked with radioactive material with her bare hands. More than 100 years after her groundbreaking work, Sophie Hardach travels to Paris to trace the lingering radioactive fingerprints she left behind. The Geiger counter starts flashing and buzzing as I hold it against the 100-year-old Parisian doorknob. I am standing in the doorway between the historical lab and office of Marie Curie, the Polish-born, Paris-based scientist who invented the word "radioactivity" – and here is an especially startling trace of her. The museum that houses the lab has invited me in here to track radioactive handprints left by her when she worked here in the early 20th Century. Here, on the doorknob, is one such trace. There's another one on the back of her chair. Many more of these invisible traces are dotted all over her archived notes, books and private furniture, some only discovered in recent years. The Geiger counter's reaction, and the numbers on the display, suggest the presence of above-background radioactivity, though only at low and non-threatening levels. In microsievert, which measures the potential impact of radiation on the human body, it comes to about 0.24 microsievert per hour, well within safe limits, according to experts. Marie Curie worked here from 1914 until 1934, the year of her death, handling radioactive elements including radium, which she and her husband Pierre Curie had discovered in 1898. For most of her life, she did this with bare, increasingly radium-scarred hands. She then transferred traces of these elements onto other things she touched. Tracking the handprints through her work spaces, one can imagine how she might have gone "from the lab to the office, opened the door and pulled out the office chair to sit down", says Renaud Huynh, the director of the Curie Museum, as he guides me from trace to trace. Some radioactive traces, for example in the Curies' lab notes and notebooks, have long been known about: one analysis in the 1950s made some of them visible by using a photographic plate. The contamination showed up as dots and splodges, suggesting radioactive lab dust settling on the page, or droplets from boiling solutions of radium salts spraying onto it. Other traces have been revealed in more depth by further tests in recent years: they have been found on the doors of a cupboard from her home, on drawers, on the pages of books, on lecturing notes, and even on an extendable dining table from the Curies' family home. For every item, experts face the agonising question of whether to save it as heritage – or, in cases where the contamination is considered a public safety risk, put into a nuclear waste facility. The cupboard, for example, ended up being destroyed. Marie Curie's lab and office, whose tall windows overlook a rose garden she designed, are usually closed off by a red cordon, to be viewed but not entered by the museum's visitors. They were part of the Radium Institute, which she founded, and still sit in the heart of an active, bustling research campus. "There's a great probability that the radioactive traces were left by Marie Curie, but it could have been her daughter [Irène Joliot-Curie], who later used the same office," says Huynh. "Either way, it's a material trace of the past, it's a form of heritage. If we were to erase these traces, we would lose this memory. It might be a detail, but it evokes a mode of contamination, it evokes a certain way of working – and it also evokes an era." Huynh has invited me into the museum outside opening hours, and also into the nearby archive, to talk about these traces. Since radioactivity is invisible, I had asked him before the visit if I could bring a Geiger counter to bring the traces to life for our readers. He agreed, and also let me invite Marc Ammerich, a radiation expert, to help me measure and interpret the results. Ammerich spent 40 years working for French radioprotection agencies, inspecting the safety of France's nuclear power plants. Since 2019, he has been tasked with comprehensive tests on the museum's collection. He has tested about 9,000 items from the Curies and their family so far, including the extendable dining table, where he found two radioactive patches next to each other, like two handprints, where a person would grab the table and pull it out for visitors. Turning his attention to the Curies' legacy has been a special experience, Ammerich says: "To measure the notebooks where they write about their discoveries of radium and polonium, to measure the instruments they used – it's extraordinary. It's like holding the history of radioactivity in my hands". The 'shed years' Marie Curie was a doctoral student in Paris in the 1890s, when she came across a curious phenomenon. She was studying the recently discovered mysterious rays emitted by uranium. The scientist Henri Becquerel had described their interesting properties. The rays gave off light, and also, they made air conduct electricity. Curie proposed the word radioactivity for these peculiar rays – coining the word still used today. Testing various ores for their levels of radioactivity, Marie Curie then noticed something surprising: some of these ores were much more radioactive than the known radioactive elements they contained (uranium and thorium). After checking her measurements, she concluded that there was only one explanation: there must be another, not yet known, highly radioactive element in these ores. To find this unknown element, she began refining a uranium ore called pitchblende, removing all known elements from it, until only the mystery element would be left. Excited by the project, Pierre joined her. They crushed the ore, dissolved the resulting powder in acid, filtered it in many different steps, and obtained an increasingly concentrated, and increasingly radioactive product, Huynh explains. It was an arduous process. As Marie Curie herself put it: "The life of a great scientist in his laboratory is not, as many may think, a peaceful idyll. More often it is a bitter battle with things, with one's surroundings, and above all with oneself". Not having access to a proper lab, they worked in a store room, and then, a leaky shed behind a university building. In Marie Curie's description, the shed was furnished with "some worn pine tables, a cast-iron stove" – and it lacked any safety provisions whatsoever: "There were no hoods to carry away the poisonous gases thrown off in our chemical treatments". And yet, "it was in this miserable old shed that we passed the best and happiest years of our life, devoting our entire days to our work", she writes. In 1898, at the end of this backbreaking process of refining the pitchblende and then further refining tiny, highly radioactive crystals, they announced that they had discovered two new elements: polonium, which they named after Marie Curie's homeland, Poland; and radium. "It was a very toxic environment," says Huynh. "Because there were not only radioactive vapours, and radioactive dust, but they also used many chemical products to break up the pitchblende that are banned from laboratories today, such as mercury." The shed no longer exists, having been torn down; the lab in the museum is where Marie Curie later worked. In recent years, Ammerich conducted a wide-ranging inspection and safety review for the museum. He and his team removed surface contamination, such as weakly radioactive dust, from furniture in the preserved office. The remaining, faint radioactivity is from traces that sunk into the wood or metal and are now inside it, meaning that even if someone were to now touch the furniture, they would not transfer any contamination. "The lab was already decontaminated in the 1980s," says Huynh. At the time, the practice in the museum was to "try and scrub off the contamination with abrasive sponges, and if radioactivity was then still detected, it meant it had sunk into the material, and they'd throw away the whole thing and replace it" with a copy, he says. The lab bench, for example, was replaced with a replica, Huynh explains. Today, weakly radioactive traces such as the ones on the chair and doorknob are allowed to stay in place, he says, and are considered as heritage. "These historical traces of radioactivity are so important because they show the working conditions of Marie Curie at the time. They should be preserved at all costs," says Thomas Beaufils, a professor and museologist at the University of Lille who specialises in the conservation and protection of radioactive heritage. "There is no other place in the world where radioactivity has been spread throughout a lab and office by Marie Curie. It has a huge heritage value." Today, radium – which Marie Curie discovered during her PhD research – is no longer used in France, having been replaced with safer and more manageable elements, Ammerich explains. And the way scientists work with radioactive elements has of course fundamentally changed, he says. "If Marie Curie were a PhD student today, she would first of all need to apply for a range of permits to work with these radioactive materials," says Ammerich. "And she would only be allowed to do her research in an authorised lab, with all the necessary safety and ventilation equipment. She certainly wouldn't be handling the materials on a table or lab bench, she would be using a glove box," a sealed container with the radioactive material inside, he adds. Testing history When we planned the visit, Huynh said we could measure anything we wanted in the lab, office and archive, as long as it could be done safely. Two photographers accompanied me and documented our tests – which ended up taking six hours, as we journeyed through Marie and Pierre Curies' spellbinding research and discoveries. Given the wealth of objects in the archive, I decided to focus on things that might transport us to two crucial periods in the Curies' story: their early years, discovering radium together; and Marie Curie's time leading research at the Radium Institute, alone, after Pierre's death in 1906. Ammerich shows me how to take meaningful measurements. He has brought a briefcase filled with different detectors. One is a yellow Geiger counter, about palm-sized, for two types of measurements. The first of these tests, measured in "counts per second", detects whether radiation is present, in the form of alpha, beta or gamma rays. This overall test helps detect whether the object we are measuring is radioactive, or not. If an object does register above-background radioactivity, the second measure we take shows the potential impact of these rays on the human body, measured in microsievert per hour. This helps check if an object's level of radioactivity poses a risk to human health, by potentially raising the long-term risk of cancer. We also use a spectrometer, which can pick up more detailed information, such as which radioactive element is being measured. And we test some non-radioactive surfaces, as a control. Ammerich had already previously tested all the objects we look at, as part of his evaluation of the collection. He has also assessed if there was a risk to museum visitors or staff, from the weakly radioactive objects. "There's no danger, nothing," he says, for either of those groups, based on his assessment. Nor was there any risk to us as we measured these objects – which we simply did to allow me to understand, and report on, the radioactive traces. A radioactive lab note In an office above the museum's archive, Huynh opens a box with a small radioactivity warning sticker on the side. It contains a handwritten, faded document, a lab note written by Marie and Pierre Curie in 1902. "On the top of the page you see Pierre Curie's handwriting, and below that, the neater handwriting, that's Marie Curie's," he says, pointing at the faded lines. The two habitually shared notebooks, he explains: "In their lab notes, you see very clearly how they worked together as equals, with mutual respect. It was a really intense and very respectful scientific collaboration, a real exchange." When Pierre Curie was put forward for the Nobel Prize together with Becquerel in 1903, "it was he who insisted that his wife should also be included", Huynh adds – leading to all three jointly winning the prestigious prize, which had never been awarded to a woman before. Dating from those early years in the hangar, the note captures a crucial moment in their research, Huynh explains: "It's where she calculates the atomic weight of radium," a key step in their quest to prove that this new element exists, he says. Marie Curie writes the result down as 223.3 – very close to the weight as it is known today, of 226. "It's a remarkable document," Huynh says. "It's the calculation proving that, yes, it has an atomic weight that makes it different from other elements, that gives it a place in the periodic table, and it's also written during a period of such intellectual energy." In fact, Frédéric Joliot, the Curies' son-in-law, made a print of this lab note with a photographic plate in the 1950s to show the contamination, and also measured it with a ticking Geiger counter – possibly making him the first person to investigate his extended family's radioactive heritage. "It's moving to hear ... the very same radium extracted and handled by Pierre and Marie Curie", making itself known through the detector's sound, he wrote at the time. The secrets of Parisian pavements As we measure the objects, we also take measurements of surfaces that have nothing to do with the Curies and their legacy, to give us something to compare our other readings against. An ordinary Parisian parquet floor, in a building that was never used by the Curies, gives a reading of 0.11 microsievert per hour. This is the background radiation which an average person is exposed to every day, from natural sources such as the ground and cosmic radiation, Ammerich says. He points out that we humans are also radioactive ourselves, as we contain radioactive elements such as potassium. In France, the legal limit of a person's exposure to radioactivity, in addition to natural and medical exposure, is 1 millisievert (1,000 microsievert) per year for members of the public. For workers in nuclear facilities, it's 20 millisievert (20,000 microsievert) per year. Placed on an ordinary stretch of pavement outside the building, the reading rises slightly, to 0.19 microsievert per hour. That's because Parisian pavements are made of granite, which can contain radioactive elements such as uranium, Ammerich says. We take turns carefully hovering the Geiger counter over the Curies' lab note. It buzzes, having detected above-background levels of radioactivity, especially towards the bottom of the page, where human hands may have touched it more. But the levels are very low, and from a human health and safety perspective, the lab note is not dangerous at all, Ammerich and Huynh say. In the museum, we measure the public areas where visitors walk – they measure at background levels, of around 0.11 microsievert per hour: "It's the level of natural radioactivity, of the ground, the Sun, the people all around us, with their potassium," says Ammerich. The back of Marie Curie's office chair; the doorknob; and an instrument called a piezoelectric quartz electrometre, which the Curies used to measure radioactivity, all measure somewhat above those background levels, but still well within safe ranges. The overall safety assessment of any given place or object is not only based on such measurements, Ammerich explains. Instead, it is estimated based on a range of factors, including the length of time of the exposure, the distance to the object, and which parts of the body are exposed to it. The different types of rays also matter: alpha rays can be mostly stopped by human skin, and completely stopped by a sheet of paper, he explains. Gamma rays are more penetrating, but can be stopped by concrete or lead. Radium, the chief source of contamination for the Curies' heritage, gives off alpha, beta and gamma rays, but mostly alpha. Ammerich's risk assessment for the museum's visitors as well as for museum staff was based on thorough measurements of all the objects, along with those comprehensive factors, and found that there was no risk. 'Glowing like fairy lights' The Curies themselves noticed that their radioactive materials, such as radium salts and radioactive gases, were contaminating everything else in the shed. "The dust, the air in the room, the clothes are radioactive," Marie Curie reports in her doctoral thesis in 1903. Still, at this stage, the Curies did not seem worried for their safety: their only concern was that the contamination might muddle their scientific results. Marie Curie and others noticed, over time, that her hands were "calloused, hardened, deeply burned by radium". Pierre Curie repeatedly put radium salts against his skin, to test the effect. Burn-like, red lesions appeared on his skin. This did not seem to scare him; on the contrary, he and other scientists thought this effect could be useful for treating tumours – an insight that led to the first effective cancer treatments. Only later did scientists discover that being exposed to radium, and other radioactive materials, can also raise one's risk of cancer. Other scientists at the time also experimented freely with radium, for example, dabbing radium salts on their temples or their closed eyelids, and reporting that it filled their closed eyes with light. Mainly, the Curies observed their newly discovered radium with hope and wonder: it gave off warmth, and glowed beautifully in the dark. They went to the shed at night to marvel at the bottles and tubes of radium salts on the rickety shelves and tables: "Like faint fairy lights," Marie Curie observed. The Curie cupboard Not all of the Curies' heritage is being preserved. Even today, some of it ends up in nuclear waste facilities, in cases where public safety concerns override heritage protection. The day before my visit the Curie Museum and its archive, I meet up with experts from Andra, France's agency in charge of radioactive waste. Over lunch on a cobblestoned square close to Andra's headquarters just outside of Paris, they tell me about some of the more surprising tasks that fall into their remit. Andra oversees radioactive waste from France's nuclear power plants, as well as from research labs, hospitals and so on. About once a week, they get a call from people who have found potentially radioactive antiques in their home – alarm clocks, for example, from the 1920s, when radium was considered harmless, and used in paint on clocks. It was even used in cosmetics and special soda fountains with radium in them, to make radioactive water, which was thought to be healthful. Andra's experts test these heirlooms, and put the contaminated ones into radioactive waste facilities. In some cases, antiques such as the fountains are decontaminated by removing the radium, then given to the Curie Museum. "We walk in Marie Curie's footsteps," says Nicolas Benoit, a specialist at Andra who oversees the remediation of sites polluted by radioactivity. "Every time we visit a site where there's radium, we think of her. And we aren't angry with her, not at all, because at the end of the day – yes, they handled the radium in a bit of a slapdash way, but at the time, there wasn't an awareness of its dangers." He pauses, then adds: "And there's a bit of pride as well, because it's as if we're closing the circle, we're finishing her work", by taking care of the contaminated objects from the radium era. In 2020, Benoit led an unusual operation: a visit to the home of Hélène Langevin-Joliot, a nuclear physicist and part of the Curies' dynasty of scientists. She is the granddaughter of Pierre and Marie Curie; her parents, Irène Joliot-Curie and Frédéric Joliot, won a joint Nobel Prize in 1935 for their discovery of artificial radioactivity. In fact, Irène thanked her mother, Marie, for sharing her stash of rare polonium with her, which helped h Irène and Frédéric with the research that led to the discovery. A love of science was passed down in the family, along with friendships with other scientists and their families, including Albert Einstein. Langevin-Joliot had a number of family heirlooms from her parents and grandparents in her home, which she suspected might be slightly contaminated. She was not worried for herself, having lived with them for many years, being in good health, and considering the risk to be low. But she did not want to leave them behind, and force others to deal with them. After talking to Huynh, the museum director, she invited Andra's experts into her home, to measure the heirlooms. "It's one of the best memories of my life," Benoit says, of the operation. "If you imagine that Marie Curie used those objects – that was really moving for us, it's not something you get to do every day." They tested a cupboard that used to belong to Marie Curie – photos exist of her standing next to it, he says – and had been handed down in the family. "We emptied it, and tested it. The contamination was above all on the doors, where you open the cupboard. And on the locks, on the drawers ... everywhere she [Marie Curie] touched," he says. "We tried decontaminating the wood, without damaging it, but it wasn't possible," because the radium traces had sunk into it, he adds. The worry was that leaving it in place could mean it would end up with a future owner who might not know about its past, and might use or process the wood in ways that would spread the contamination. With Langevin-Joliot's agreement, the cupboard was cut into pieces and incinerated in a radioactive waste facility, Benoit explains: "The cupboard doesn't exist anymore. It's sad, it was heartbreaking, but that's how it is." Thinking about risk Today, radium is sometimes described as the most radioactive natural element ever discovered. But Benoit challenges that description. From a safety perspective, "saying that one element is more radioactive than another, doesn't really make sense", he says, since estimating radioactivity is more complex than just measuring an element's level of activity (the rate at which the radioactive element decays, measured by counting the number of disintegrations per second). One must also consider its half-life, the time required for half of it to decay – in the case of radium, 1,600 years – he says, as well as the actual impact on humans, which in turn depends on a range of factors. "If you take carbon-14, for example – yes, that's an element that emits radiation. But only over a very weak distance, only a few centimetres," he says. He puts his finger on the table, between our coffee cups. "So if it were placed here, we could sit where we're sitting, and we wouldn't risk anything." The lead coffins There is a tragic side to the Curies' legacy. Already in the early days of working with radium in the shed, Pierre noticed that he felt increasingly sick. Marie Curie also felt sick, struck by a mysterious fatigue. She died at 66, of leukaemia, a cancer of the blood. It may not have been radium that killed her: Huynh says the culprit was more likely her work with X-Rays during World War One, which would have exposed her to the kind of radiation known to raise the risk of leukaemia. Irène and Frédéric Joliot-Curie died in their late 50s, also of cancer. Before his death, Frédéric had been especially active in improving safety regulations and equipment for people working with radium, Huynh says. Today, the Curies are entombed in a crypt of the Panthéon monument in Paris, in lead coffins, to block any potential radiation from traces inside (or on) their bodies. They were previously buried in a cemetery just outside of Paris. In the 1990s, before they were transferred to the Pantheon, radiation experts exhumed and tested their bodies, detecting some radioactive contamination, before laying them to rest in the lead coffins. For Ammerich, the experience of handling the couple's belongings remains very moving. "When I tested Marie Curie's diary, where she writes about her husband's death – I'll be honest with you, I had tears in my eyes," he says. In his view, it would be a shame to remove the small remaining traces in her Paris office: "Imagine if you cleaned everything off, and then in the future, nothing would prove what happened here." Beaufils, the museologist, also emphasises how important it is to save and protect this kind of radioactive heritage. "From a historical point of view, our societies are built on these kinds of objects and memories from the past. If we don't protect our material heritage, we'll be a nation, a society, without any historical depth," Beaufils says. "And a society without depth will struggle to develop, and to thrive," both from a social and technological point of view, he adds. Huynh sees the Curie Museum as "a link between the past and the future", especially given its location on a busy cancer research campus, the Institut Curie Research Center. When I visit, I see researchers mingling in the rose garden by Marie Curie's lab – dressed in jeans and T-shirts, not suits and long dresses, as they would have been during her time. Huynh tells me there are also active labs on the floors above and below the museum. "Many researchers here are very proud of that heritage," he says. "It's a kind of 'Curie spirit'." -- For more science, technology, environment and health stories from the BBC, follow us on Facebook, X and Instagram.
