Accidental ingestion of batteries can be life-threatening

Thermal runaway reactions can cause batteries to catch fire or explode

If a lithium-ion battery is heated, punctured, crushed, or short-circuits due to manufacturing flaws or degradation, the cathode and anode can make contact without the resistance provided by a circuit. The ensuing spike in chemical reactions increases the temperature and can release oxygen, initiating and intensifying burning of the battery's interior.

Pollution from lead battery recycling has led to widespread contamination

Many small-scale operations worldwide remain unregulated, bypassing environmental regulations and causing increasing health threats, primarily to children. A 2020 report by UNICEF found that one-third of the world's children are being poisoned by lead from recycled batteries, among other sources.

Being near a lightning strike—even without getting struck—can be fatal

Because animal tissue is generally more conductive than soil, electricity moving along Earth's surface after a strike tends to travel up and back down an animal's legs, discharging dangerous amounts of energy along the way, with risks increasing the farther apart the legs are. This ground current accounts for about half of all lightning-related deaths and injuries in humans.

How to safely dispose of every kind of battery

As lithium-ion batteries have proliferated in phones, e-bikes, power tools, and dozens of other devices, improper disposal has become a leading cause of fires in recycling facilities and garbage trucks. Battery Safety Now partnered with the US Forest Service's Woodsy Owl campaign to provide guidance on how to recycle batteries by type, including locator tools for drop-off sites.

During manufacturing, lithium-ion and alkaline batteries are tested for short-circuiting

Lithium-ion batteries are made by manufacturing anodes, cathodes, and electrolytes via chemical processes, assembling these components into cells, and enclosing multiple interconnected cells within a protective casing. Disposable alkaline battery production involves filling steel containers with preforms—rings of powdered cathode material—paper-based separators, electrolyte solution, and an anode gel.

Gradual chemical build-up reduces the effectiveness of rechargeable batteries

During charge cycles, small chemical deposits gradually form a film on the electrodes where they make contact with the electrolyte, trapping ions that would otherwise facilitate the flow of electricity. Mechanical degradation from electrode wear and electrical shorting from structural instability can also reduce battery capacity.

Batteries range in size based on their purpose, cost, and manufacturability

Lead-acid batteries used in combustion vehicles are resilient to temperature extremes, low-cost, and provide high surge current, which is needed for initial ignition. Alkaline batteries, including AA, AAA, and B, have long shelf lives and supply the low, steady power required for electronics with minimal demand fluctuations.

Batteries store energy in chemical bonds that can be turned into electricity

To achieve a more stable, nonreactive state, many elements in nature are reactive and will seek to lose electrons via oxidation or gain electrons through reduction reactions. By pairing an oxidizing chemical with a reducing chemical in a battery, electrons will naturally flow between them, producing an electric current.

The benefits of 3D printing batteries, from safety to sustainability

Rather than using the liquid electrolyte commonly found in lithium-ion batteries, 3D-printed batteries would use a solid layer, which can be custom-built into different shapes, deliver higher energy density by building thinner layers, and be fabricated with fewer raw materials compared to injection molding.

Tooth brushing immediately after vomiting rubs in corrosive acid, damaging teeth

Brushing right after vomiting can further erode the enamel by rubbing in stomach acid and etching it onto tooth surfaces. Instead, research suggests you should consider rinsing your mouth with water and baking soda in the short-term and waiting to brush your teeth for 30-60 minutes.

Exposure to ionizing radiation from nuclear accidents can damage DNA

The damage can increase the risks of cancer, cataracts, heart disease, and other illnesses based on exposure times and intensities. Contaminated food, water, air, or soil from near nuclear accidents can further prolong one's exposure.

Benjamin Franklin described a series of static electricity storage jars as 'batteries'

Discovered over 50 years before the first electrochemical cell was invented, Leyden jars stored electric charge between the metals inside and outside a liquid-filled container. Franklin was the first to use the term "battery" in an electrical sense, though his multiple-jar device—lacking chemical reactions—was actually a series of capacitors.

Breaking down the challenges of alkaline environments and how extremophiles survive them

These areas are far less acidic than the interiors of most organisms' cells, and this imbalance draws protons that are needed for various metabolic processes, including energy production, out of cells. To counter these effects, some alkaliphiles have developed stronger proton regulation across their cellular membranes and proteins that drive these processes with greater stability amid such acidity imbalances.

Natural toxins produced on plants or consumed by animals may cause food poisoning

When humans eat plants with certain natural toxins on them—including a family of toxins called aflatoxins that fungi produce on crops like peanuts and corn— they can become ill with food poisoning. Toxins can still harm humans even if animals or plants appear fine to the human eye. The World Health Organization advises that we should throw away moldy or discolored foods, refrain from eating wild plants or mushrooms that aren’t definitively nonpoisonous, and remember that just because something is “natural” it’s not always safe to eat.

Learn how cholera bacteria sicken humans

Once a person has ingested large amounts of the bacteria, typically through contaminated water, cholera bacteria begin producing and releasing a toxin inside their host. It attacks the mucosal lining of the intestine, making it hard to absorb liquids. This process leads to cholera's characteristic symptoms, like voluminous, watery diarrhea.

A family's yearslong poisoning

Over 14 years, a southern Indian family slowly lost six members, several of whom were found foaming at their mouths. Upon the third death, a post-mortem examination was requested, revealing cyanide had been ingested, though it was ruled as self-inflicted. Several will edits and three deaths later, relatives turned a critical eye toward Joliyamma "Jolly" Joseph, who had married into the family and been present at each death.

Firework or sparkler burns, even if they cover a relatively small area of skin, can significantly affect our range of motion.

Cellular aging and deterioration leads to tissue (and overall) aging

Cells are the building blocks of life, forming tissues and organs that keep our bodies working. As we age, cellular changes have progressive consequences on both the structure and function of our organs. This article examines this complex relationship as it relates to the incremental changes associated with aging.

How the gut microbiome can affect heatstroke risk

Some research suggests that our gut microbiome influences our risk of exertional heatstroke. If exercise boosts our body temperatures to unsafe levels, increasing gut permeability, that can cause a "leaky" gut—allowing bacteria and other gut microbes to leak into the bloodstream and potentially trigger endotoxemia, a potentially life-threatening inflammatory response that can occur with heat exhaustion and heatstroke.

Yes, you can take too many vitamins and they can make you sick

Too much of vitamins A, D, E, and K (which are fat-soluble) can build up in the body and cause serious health problems, including liver damage, kidney stones, and blood clotting irregularities. Excess iron and calcium can also make it harder for the body to absorb other needed nutrients.

Nerve axons become damaged by leprosy, so patients may lose feeling in their skin

Infection of the peripheral nerves—nerves outside the brain and spinal cord—is a known complication of leprosy. That damage can cause patients to lose their sense of touch and the ability to feel pain or temperature in affected areas, leading to accidental injury.

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

Volcanic ash is composed of fragments of volcanic rock, minerals, and glass

These abrasive particles are hazardous to aircraft. They can melt within engines and re-solidify on turbine blades, preventing forward propulsion. If inhaled, chemicals within ash can be toxic, and the particles can embed themselves into the lungs' ducts, causing suffocation.

See images of medical cases of firework injuries shared on this 'Instagram for doctors'

Included photos include scans of missing or damaged digits, a chunk of missing flesh, a facial injury from a homemade firework in a glass bottle that exploded in the patient's hand before it was thrown, and an injury where a patient's finger bone flew into someone's leg.

Sony set the standard for cylinder-shaped batteries when it repurposed manufacturing equipment used to make rolls of magnetic recording tape.

How does cancer actually kill someone?

While the emotional and physical tolls of cancer are often clear, the innerworkings of how cancer kills can be confusing — and terrifying to discuss. Here, oncologists explain how cancer can progress.

Harvard and MIT researchers are developing life-saving tattoos

Tattoos aren’t just a fashion statement. Scientists are trying to find life-saving applications for them. Harvard and MIT researchers are developing tattoo inks that react to body chemicals, alerting diabetics to blood sugar fluctuations or athletes to dehydration. Someday, patients may observe their body chemistry with tattoos that change colors.

We may be using Q-tips in our ears—even when we shouldn't—because they can stimulate pleasure nerves

People continue to use Q-tips inside their ears even though we know it's risky. Some clinicians suggest that beyond the desire to get water out, this may be because the nerve bundle called the vagus nerve, which spans from the brain to the large intestine, can be stimulated that way, causing a pleasurable sensation in other body parts including the heart, belly, or genitals.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

Poison ivy is in the same family as mangoes, cashews, and pistachios—and they all produce oily urushiol in their raw, unprocessed state—but they are typically prepared in ways to avoid causing human discomfort.

An investigation suggests a Scottish island became awash in forever chemicals via seafoam and seaspray—raising questions about what that means for the safety of other coastal areas.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

Learn more about the history of fireworks, which dates back to an accidental invention during an alchemist's quest for information about immortality.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

Watch what the Ebola virus does inside our cells and organs in order to spread and survive.

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.

Read a deep dive on the 'all-purpose healing' peptide BPC-157.

Dirty lightning is a thunderstorm created from friction between rising and falling flows of ash and smoke during volcanic eruptions.

Tattoos remain visible on your skin thanks to immune cells called macrophages

In 1984, Operation Smash Hit intentionally crashed a 239-ton train into a nuclear waste canister at 100 miles per hour to prove the canister's safety, which remained completely intact and lost just 0.29 of its 100 pounds of pressure.

When caught in the mouths of cardinal fish, seed shrimp release glowing, bioluminescent chemicals, which alert predators of the cardinal fish, prompting the shrimp's ejection.

The use of fungi to detoxify land and water—a process known as mycoremediation—has been used to clean up natural resources affected by the 2025 California wildfires.

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

Lesser-known phobias include turophobia, or the fear of cheese, and nomophobia, the fear of being without your cell phone.

The tragic Pulitzer Prize-winning image 'The Vulture and the Little Girl' (1993) generated controversy, raised concerns about ethics in photography, and eventually led to the photographer's death.

Massive 3D printers have been used to build homes by stacking layers of 'concrete toothpaste,' a fire-resistant material that effectively insulates against outside noise.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes