Research sheds light on disruptive impact of electromagnetic noise pollution on bat migration

Bangor University

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soprano pipistrelle bat

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Credit: Christian Giese

New research has unearthed new insights on the disruptive and detrimental effects that human produced electromagnetic noise can have on the ability of bats to migrate effectively. 

The study, published in the journal, Science, and led by researchers at Bangor University, the University of Latvia and the University of Oldenburg, in Germany, has revealed unexpected effects of exposure to electromagnetic noise that is an ever-present feature of urban environments.

The team of researchers exposed soprano pipistrelle bats to weak broadband radiofrequency noise (0-300MHz) for about 30 minutes while they were observing the sunset, then tested their flight orientation later in the night. Previous studies have shown that such noise can disrupt animals' ability to sense the magnetic field.

Because soprano pipistrelle bats migrating towards their wintering grounds are known to calibrate environmental cues at sunset for navigation later at night, the researchers predicted that this would disrupt the bats' ability to sense the magnetic field and thus their calibration of their internal compass system, but would only effect bats when exposed during that crucial calibration period.

They found the bats exposed to this noise took off in random directions, unlike untreated bats, which oriented normally in the expected migratory direction. However, much to the surprise of the researchers, further studies indicated that bat’s orientation is disrupted regardless of whether the exposure was during this crucial calibration period or after it, when the sun had set.  

Most surprisingly, the disruptive effects of this electromagnetic noise lasted for several hours beyond the exposure period, suggesting a “carryover effect” of the brief exposure. This was not predicted by the known effects of this electromagnetic noise on the magnetic sense, which is expected to end when the noise is no longer present. 

Their findings suggest that electromagnetic noise pollution has the potential to have a greater effect on animal behaviour than had previously been assumed. The research thus raises questions about the ecological consequences of electromagnetic noise for wildlife moving through human-dominated landscapes, such as animals that migrate seasonally, even if they do so only briefly.

Richard Holland, Professor in Animal Behaviour at Bangor University said, “This finding was quite surprising. Our intention was to see how the noise would affect the magnetic sensing system of bats, but the results suggest that the impact of this electromagnetic noise is more complicated than that. Although it is known that electromagnetic noise in this range disrupts the magnetic sense, it was not previously assumed to have a significant impact on migrating animals, because it is more prevalent in cities than rural areas. It was assumed that because animals would move rapidly through it, they would not be affected for very long, if at all. However, our findings indicate that even brief exposure can have effects that last beyond the period of exposure, and independently of other cues.”  

Will Schneider, Research Fellow in Bangor and co-author of the study said,

“The reason for these effects is uncertain. It may be that the effect is on their interpretation of the magnetic field, for example, because the electromagnetic noise makes it look unusual, the bats decide to ignore it. On the other hand, it might be that it introduces some sort of stressor, that makes the bats decide not to migrate that night, which is why they head off randomly, instead of in the migratory direction, like the untreated control bats. Either way, this surprising carryover effect has the potential for significant ecological consequences that were not predicted by our current understanding of the effects of electromagnetic noise. It is also worrying that current exposure standards are designed exclusively to humans, leaving wildlife vulnerable even within the confines of these guidelines.” 

 

Contact information: Richard Holland r.holland@bangor.ac.uk 

Will Schneider w.schneider@bangor.ac.uk  

 

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Journal

Science

DOI

10.1126/science.adq4418 

Method of Research

Observational study

Subject of Research

Animals

Article Title

Disruptive effects of brief radiofrequency noise exposure on migratory bat navigation

Article Publication Date

28-May-2026

COI Statement

Authors declare that they have no competing interests.

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• Research sheds light on disruptive impact of electromagnetic noise pollution on bat migration

 

Pigeons navigate using magnetic sensors in their livers

Immune cells packed with iron could help birds detect Earth’s magnetic field

Max Planck Institute of Animal Behavior

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Homing pigeon being released by scientist at Max Planck Institute of Animal Behavior in Germany.

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Credit: Christian Ziegler/ Max Planck Institute of Animal Behavior

• Previously unknown navigation mechanism: pigeons may sense the Earth’s magnetic field using iron-rich immune cells in their livers, a quantum effect.
• Navigation experiments: removing iron-containing immune cells in the liver disrupted pigeons’ sense of direction under overcast skies.
• Sensing via the immune system: findings suggest a new link between immunity and sensory perception in birds, and potentially other animal species.

How pigeons fly hundreds of kilometers and still find their way home has long fascinated people. Now, researchers say a surprising answer may be hidden, not in the brain or eyes of birds, but in the liver.

A study published in Science suggests that special cells in the liver of pigeons can sense the Earth’s magnetic field, giving the birds an internal compass.

The special cells, known as “macrophages,” are immune cells that break down old red blood cells. As part of this process, they accumulate iron, giving them quantum properties that may allow them to respond to magnetic fields. Without these cells intact, pigeons could not navigate home, the study shows.

“We didn’t expect immune cells to act like sensors for magnetic fields at all. Our results reveal a previously unknown mechanism for magnetic perception in animals,” says Prof. Christian Kurts, Director at the Institute of Molecular Medicine and Experimental Immunology at the University Hospital Bonn, and one of the study’s co-senior authors.

“What looks like a ‘gut feeling’ in bird navigation may actually have a physical basis,” adds Prof. Martin Wikelski, Director at the Max Planck Institute of Animal Behavior and the other co-senior author of the study.

The source of magnetic sensing

For decades, scientists have known that migratory birds and homing pigeons rely in part on the Earth’s magnetic field to navigate. But exactly how they detect it remains one of biology’s unsolved mysteries. Competing theories have suggested that birds might “see” magnetic fields through light-sensitive molecules in the eye, or detect them using tiny magnetic particles in the beak. None has come up with convincing experimental support.

The new study proposes a different mechanism for magnetic sensing, supported by a combination of lab tests and behavioral experiments. The team included immunologists from the University of Bonn and the University Hospital Bonn; physicists from the University of Duisburg-Essen; and ornithologists at the Max Planck Institute of Animal Behavior (MPI-AB).

To identify where magnetic cells are found in pigeons, the researchers used techniques known as “vibrating sample magnetometry" and “magnetic cell separation” to screen organs thought to be involved in magnetic sensing, including the eyes, beak, and brain. They also examined the liver and spleen.

“We had some clues that the liver and spleen have magnetic properties, because they break down red blood cells and so store much iron in the body,” says first author Dr. Clivia Lisowski, from the University of Bonn and the University Hospital Bonn, who led the immunological work.

The results supported that idea. Of all the tissues examined, the liver showed the highest concentration of iron.

“Iron is crystallized in oxide nanoparticles making the cells superparamagnetic and reactive to magnetic fields. We found by far the strongest magnetic response in liver tissue,” adds Prof. Ulf Wiedwald, from the University of Duisburg-Essen.

Further analysis identified macrophages in the liver as the cells responsible.

From sensing to navigating

To test if liver macrophages played a role in navigation, the ornithological team conducted experiments on pigeons that were trained to return from distances over twenty kilometers back to their aviary at the MPI-AB in Konstanz, Germany. After the macrophages were removed, pigeons lost their sense of direction on overcast days when the sun was obscured. When the sun was visible, however, the pigeons successfully navigated home, likely using solar cues. Together, these results illustrate the mechanism behind how birds use magnetic sensing, in addition to the sun‘s orientation, for navigation.

With evidence that these cells influence navigation, the researchers then looked for how signals from the liver might be relayed. Electron microscopy showed that the iron-rich macrophages sit close to nerve fibers, suggesting a pathway for magnetic information to reach the brain.

Lisowski says: “These findings provide the first concrete evidence of how the Earth’s magnetic field can be perceived within the body and passed on to the brain to guide movement.”

The study brings together known biological processes, including iron metabolism and how the immune and nervous systems communicate, into a clear answer to the fundamental question of how animals navigate.

“Animal navigation is one of the most fascinating phenomena in nature,” says Wikelski. “If immune cells are part of how birds sense direction, it would fundamentally change how we understand navigation.”

Many questions remain, particularly how signals from these cells are processed in the brain. Beyond birds, these findings could have implications for animals such as sharks that navigate without light. It’s possible that other animals, and perhaps even humans, may respond to magnetic fields in ways not yet understood.

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Journal

Science

DOI

10.1126/science.ady2486 

Method of Research

Experimental study

Subject of Research

Animals

Article Title

Homing pigeon navigation relies on superparamagnetic macrophages under overcast conditions

Article Publication Date

28-May-2026

 

Electron microscopy image of pigeon liver tissue shows hepatic macrophage (blue) in contact to nerve fiber (yellow), which enables them to transmit (“magnetic”) information to the pigeon brain.

 

Histology of pigeon liver tissue, depicting iron-containing macrophages (blue).

 

Electron microscopy image of pigeon liver tissue, with full colorization of cells:

• blue = hepatic macrophage
• yellow = nerve fiber
• bright green=connective tissue
• dark red=endothelia
• orange=capillary with blood fat and proteins
• beige/dark pink=nuclei
• dark green=fibroblas

Credit

Lisowski et al. (2026) Science

COI Statement

Participating institutions and funding: The work was funded by the German Research Foundation (Collaborative Research Center 1454 and CRC-TRR 270, Gottfried-Wilhelm Leibniz Prize for C.K.) and the Max Planck Society as well as the Gordon and Betty Moore Foundation and the Academy for the Protection of Zoo Animals and Wildlife. C.K. is a member of the DFG Cluster of Excellence ImmunoSensation³ at the University of Bonn.

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• Pigeons navigate using magnetic sensors in their livers
  (Max Planck Institute of Animal Behavior)

Supermarket receipts show trends in menstrual pain relief

An analysis of 211 million supermarket transactions found that more than a quarter of customers buying menstrual products bought pain relief at the same time

PLOS

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Fig 1. Average (mean) individual summary statistics for Menstrual, Pain and Menstrual Pain customer sets via analysis of transactional logs between 30th April 2006 to 16th April 2015. 

 

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Credit: Image Credit: Sivill et al, PLOS Digital Health, 2026

 

More than a quarter of women buying menstrual products also purchase pain relief at the same time—and those in lower-income areas are significantly less likely to do so—according to a new study published this week in the open-access journal PLOS Digital Health by Dr. Victoria Sivill of the University of Bristol, UK, and colleagues, which used supermarket loyalty card data to map menstrual pain disparities across England.

Menstrual pain is a common concern affecting many individuals globally. Existing research highlights its negative impact on daily activities, including school and work attendance.

 

In the new study, researchers analyzed anonymized loyalty card data from a major UK health and beauty retailer, encompassing 211 million transactions by 3.4 million individuals between 2006 and 2015. They analyzed how often shoppers purchased menstrual products at the same time as pain relief, and how that compared to a customer’s baseline rate of buying pain relief.

 

The analysis found that 26.7% of customers who purchased menstrual products also bought pain relief in the same transaction. These customers were nearly four times more likely to buy pain relief while buying menstrual products compared to other shopping trips. As a validation of the approach, the most common interval between consecutive menstrual purchases across the dataset was exactly 28 days—consistent with the average menstrual cycle.

 

Regional income emerged as the strongest predictor of menstrual pain purchases: customers in the lowest-income areas were 32% less likely to purchase pain relief at the same time as menstrual products compared to those in the highest-income areas. The authors note that lower rates of pain relief purchases in deprived areas likely reflect an inability to afford over-the-counter medication rather than lower rates of menstrual pain itself

 

“The study highlights the need for greater awareness and policy interventions to address the high prevalence of menstrual pain as well as socioeconomic dimensions of menstrual pain,” the authors say. “Public health initiatives should incorporate menstrual pain relief as part of broader efforts to improve health equity.”

 Co-author Dr. James Goulding notes: "It is wonderful that smart data research in the UK is able to bring issues which may have once been overlooked in scientific settings—such as the sheer scale and impact of menstrual pain—to light. This is well overdue."

Co-author Dr. Anya Skatova adds: “Like many women, I was aware of how common menstrual pain is, but the scale of painkiller purchases alongside menstrual products was still striking. Using shopping data, we can see just how widespread the need for pain relief really is. This kind of evidence helps make menstrual pain visible at a population level and provides a strong foundation for systemic change in how it is recognised, treated, and prioritised in public health.” 

 

In your coverage please use this URL to provide access to the freely available article in PLOS Digital Health: https://plos.io/4wzrwbh

Citation: Sivill V, Ljevar V, Goulding J, Skatova A (2026) What can shopping transactional data reveal about relative prevalence of menstrual pain and period poverty in England? PLOS Digit Health 5(5): e0001308. https://doi.org/10.1371/journal.pdig.0001308 

Author Countries: United Kingdom

Funding: This work was supported by an Alan Turing Institute PhD Studentship funded under EPSRC grant EP/N510129/1 to VS, and a UKRI (MR/T043520/1) Future Leaders Fellowship to AS. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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Journal

PLOS Digital Health

DOI

10.1371/journal.pdig.0001308 

Method of Research

Observational study

Subject of Research

People

Article Publication Date

28-May-2026

 

MIT researchers develop a low-cost technique to get lithium out of rocks

The low-temperature process could unlock cleaner lithium from America’s abundant hard rock while minimizing waste.

Massachusetts Institute of Technology

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Demand for lithium has surged in recent years as lithium-ion batteries power increasingly more of our world. And yet, even as places like the U.S., Europe, and Australia have abundant lithium resources within their borders, China dominates global lithium refining. The biggest hurdle to tapping into the U.S. and Australia’s lithium is getting it out of hard rock minerals in a form that is useful.

Extracting lithium from hard rock today is an energy- and waste-intensive process that is often far more expensive than getting lithium from brine water, which also has major environmental drawbacks. Currently, lithium hard rock extraction involves baking the rock at over 1,000 Celsius and chemically leaching it to extract lithium. The rest of the rock is discarded.

Now, a team of researchers from MIT and elsewhere has developed a low-temperature process for extracting battery-grade lithium from the most common type of lithium-bearing mineral. The process uses a liquid reagent to dissolve the rock into the useful forms of its constituent parts: not just battery-ready lithium salts, but also smelter-grade alumina and cement-ready silica. After the minerals are extracted, the solvent and reagent can be recovered and used again so waste levels approach zero.

The researchers estimate the closed-loop process is half the cost of traditional lithium hard rock extraction and could make it cost-competitive with extracting lithium from brine water.

A paper describing the process was published today in Science. The researchers have already begun commercializing the technology through an MIT spinout, Rock Zero.

“By 2040, we need to quadruple production of lithium globally, which amounts to hundreds of new lithium producing assets,” says author Camden Hunt, a former project manager in MIT’s Center for Electrification and Decarbonization of Industry. “Hard rock is abundant; you can find it everywhere. But most hard rock refining is done in China. Our central thesis is if you can find an easier way to crack the rock, get lithium out, and make battery-grade lithium salts, you can change the lithium market. It aligns with the recent push to onshore production of critical minerals in the U.S.”

Joining Hunt on the paper are former MIT postdoc Benjamin Mowbray; PhD candidate Kalyn Fuelling; MIT undergraduate Jacqueline Prawira; Khashayar Jafari, a former senior research scientist at the MIT green cement spinout Sublime Systems; and Yet-Ming Chiang, MIT’s Kyocera Professor of Materials Science and Engineering.

From bathrooms to batteries

The research has its roots in a bathroom renovation. About 25 years ago, as Chiang made a trip to a hardware store to look for something that would turn clear glass blocks translucent, he stumbled on a glass etching cream that works by “eating away” at the surface of the glass. The active ingredient turned out to be ammonium fluoride.

More recently, as Chiang was brainstorming ways to chemically break apart the most abundant lithium-bearing mineral, spodumene, he thought back to that etching cream. Spodumene, like glass, consists mostly of silica. Conventional chemistry-based methods for extracting metals from ores preferentially dissolve more reactive elements and leave behind a silica-enriched residue because of the strength of silicon-oxygen bonds. By designing their process to use a mixture of water and ammonium fluoride, the researchers are able to dissolve silica first, reversing the process.

The researchers showed they could dissolve spodumene rock at room temperature, which represented a breakthrough over traditional processes requiring extreme heat. But it was still only the first step to a closed-loop system that produced useful materials.

“Dissolving silica is the hard part in mining,” Mowbray says. “The next question was how do we apply it to impactful mineral processing problems?”

The mineral spodumene is mainly made up of three elements: lithium, aluminum, and silica. Mowbray and Hunt, who both have their PhDs in chemistry, began exploring ways to refine those components separately after they were broken apart in the ammonium fluoride solution.

First, the researchers isolated lithium fluoride, a useful input for common electrolyte materials used in batteries. Chiang, who has founded several battery companies over his multi-decade career at MIT, next asked the research team if they could isolate lithium hydroxide and lithium carbonate, two lithium salts useful for making battery cathodes. The researchers went back to the lab and found they could make both by developing new processes, some of which involved adding carbon dioxide or sodium carbonate. Chiang tasked the research team with a similar challenge for the aluminum part of the rock, which was isolated using a high-temperature separation technique, and then silica, which was isolated by precipitation.

“First our goal was to produce these products, then there were additional steps of characterizing their purity and properties and making sure our products met the specifications for target markets,” Mowbray explains. “For the lithium salts, we identified the purity specifications for battery-grade lithium carbonate, the most widely used lithium salt. For the silica, we wanted it to be used as a cement additive, so we did cement reactivity tests and eventually created cubes of cement from it for strength testing using industrial methods. For aluminum, we targeted smelter-grade aluminum. If any product didn’t meet the target specs, you’d end up with a waste stream.”

The researchers then developed a process to reuse the ammonium fluoride and water that starts the reaction.

“We’re able to dissolve the rock with the spodumene in it, and that liberates all the elements, including the aluminum and lithium,” Chiang says. “The silica is in the solution, but on the way to making ammonium fluoride, ammonia gas also comes off. If that ammonia gas is then reapplied, it precipitates the silica again. That sequence gives us back the starting ammonium fluoride. That’s why it’s a circular process.”

The researchers successfully processed 17 different spodumene rock sources, showing its widespread applicability using rocks around the world.

“You’ve heard of nose-to-tail eating?” Chiang says. “We refer to this as nose-to-tail mining. Our researchers came to MIT to look for impactful problems to work on in sustainability. With their skill sets, it was just a matter of setting them loose on this problem. We went through all these steps, and for each one, I’d just say, ‘Can you do this next step?’ And a week or two later they’d say, ‘Okay, we’ve shown we can do that.’ That’s how this entire process got built.”

Scaling the process

Chiang further challenged his research team to evaluate the commercial feasibility of their new system.

“Once we had these core operations worked out, Yet encouraged us to do some math,” Mowbray explains. “Is there enough spodumene in the world to supply 100 terrawatt hours of battery production? The follow up was: If you supply all the world’s batteries with this process, what are the volumes of the co-products? Do they match global commodity markets? Then we started looking at the cost of the reagents, the cost of the energy, equipment. We started gaining conviction that this could have a big impact.”

The work has special significance for Mowbray, who grew up in a historic mining town in rural British Columbia.

The researchers worked with MIT’s Technology Licensing Office to spin out their company, Rock Zero, which is now located at The Engine and scaling up the system.

“We believe this approach is the lowest-energy, lowest-cost way of getting lithium not only out of hard rock, but period,” Chiang says. “That’s what’s motivating us to scale this. It will enable the energy transition through batteries that use lithium. This was one of the goals of The Climate Project at MIT — to work on projects that, within a short number of years, could transition from the lab to commercialization and impact.”

The work was supported in part by the Department of Energy Advanced Research Projects Agency-Energy (ARPA-E), the MIT Climate Grant Challenges program, and the National Science Foundation. The work made use of MIT.nano facilities.

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Written by Zach Winn, MIT News

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Journal

Science

DOI

10.1126/science.aec4652 

Article Title

Valorization of lithium hardrock concentrates into battery raw materials and commodity products

Article Publication Date

28-May-2026

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• MIT researchers develop a low-cost technique to get lithium out of rocks
  (Massachusetts Institute of Technology)

 

Genetic engineering of cyanobacteria for the production of sulfated polysaccharide

How gene transfer enables a non-producing bacterium to synthesize biomaterials

Institute of Science Tokyo

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Researchers produce high-value biomaterials (SPS) in Synechococcus elongatus through genetic engineering.

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Credit: Institute of Science Tokyo

Genetically engineered cyanobacteria developed at Institute of Science Tokyo (Science Tokyo), Japan, produce sulfated polysaccharides using sunlight and carbon dioxide. By transferring an entire gene cluster responsible for the production of a sulfated polysaccharide, the researchers enabled a non-producing cyanobacterial strain to produce such a polysaccharide. The research demonstrates a sustainable route for manufacturing biomaterials using photosynthesis, expanding the possibilities for synthetic biology and green chemistry applications.

Biomolecules are naturally occurring molecules that form the basis of living systems. They are widely used in the production of a diverse range of materials. One such widely used biomolecule is sulfated polysaccharide (SPS) which includes sugar molecules attached to sulfate groups. These are widely used in pharmaceuticals, cosmetics, and functional materials due to their unique physical and biological properties. However, commercially available SPSs are usually derived from animal or marine sources, which raises concerns about their environmental impact, calling for alternative SPS production methods.

In search of a sustainable production method, a research team led by Assistant Professor Kaisei Maeda from the Laboratory for Chemistry and Life Science, Institute of Integrated Research, Institute of Science Tokyo, Japan, in collaboration with Professor Satoru Watanabe from the Department of Bioscience, Tokyo University of Agriculture, Japan, developed a novel strategy to genetically engineer bacteria for the production of SPS. Their study, published in Volume 16 of the journal Scientific Reports on April 28, 2026, demonstrates the successful transfer and functional integration of an entire gene cluster responsible for producing a sulfated polysaccharide known as “synechan.”

Cyanobacteria are photosynthetic microorganisms capable of converting carbon dioxide into useful compounds. Many cyanobacterial species naturally produce diverse sulfated polysaccharides. While these emerge as promising candidates for sustainable biomanufacturing, harnessing them in a controlled and scalable way has remained challenging.

“Our aim was to transfer the complex SPS-producing systems between these organisms to enable new functionality in those species which are easier to handle,” explains Maeda.

 However, this strategy had not been previously demonstrated in these systems.

To achieve the same, the researchers focused on a model SPS-producing cyanobacterium, Synechocystis sp. PCC 6803, which produces synechan. They identified the gene cluster responsible for its production and transferred this gene system into Synechococcus elongatus PCC 7942, a model cyanobacterium that does not naturally produce SPS. Remarkably, the engineered strain began producing extracellular SPSs, confirming that the transferred genes function cooperatively in the new host.

“By introducing the full gene set into Synechococcus elongatus, we demonstrated that complex biosynthetic pathways can be reconstructed to function in a different cyanobacterial species,” says Maeda.

The findings also revealed that the SPS produced by the engineered cells was similar to that of the original compound. Microscopy and biochemical assays confirmed the accumulation of extracellular SPS. Further analysis of gene activity showed that the introduced genes were working together, along with broader changes in the cells’ metabolism. These findings highlight both the feasibility and complexity of engineering biomolecule producing systems in photosynthetic organisms.

Apart from demonstrating proof of concept, the study also provides deep insights into the adaption of cellular metabolism in supporting the polysaccharide production. The engineered strain displayed changes in growth behavior and gene expression, leading to a shift towards a stress-response state while prioritizing the synthesis of these complex molecules. These findings prove to be valuable for optimizing the production efficiency in future studies.

Overall, the study represents an important step towards sustainable biomanufacturing using cyanobacteria. By enabling the production of SPS in a controllable microbial platform, this method could reduce reliance on animal and marine resources while supporting the development of environmentally friendly production systems.

In future, advances in synthetic biology could allow researchers to optimize polysaccharide composition, improve production yields, and design entirely new biomaterials with tailored properties. Combining photosynthesis with engineered biosynthesis pathways, cyanobacteria may serve as versatile “cell factories” for a wide range of industrial and biomedical applications, paving the way for a more sustainable and resource-efficient future.

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About Institute of Science Tokyo (Science Tokyo)

Institute of Science Tokyo (Science Tokyo) was established on October 1, 2024, following the merger between Tokyo Medical and Dental University (TMDU) and Tokyo Institute of Technology (Tokyo Tech), with the mission of “Advancing science and human wellbeing to create value for and with society.”

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Journal

Scientific Reports

DOI

10.1038/s41598-026-46439-4 

Method of Research

Experimental study

Subject of Research

Cells

Article Title

Transfer of the synechan biosynthesis and regulatory pathway enables sulfated polysaccharide production in Synechococcus elongatus PCC 7942