Odor blockers use nonpolar oils to trap smelly polar molecules

Explore the chemistry of undesired body odors

This graphic highlights some of the main compounds in different body odors, including halitosis (bad breath), flatulence, and foot odor.

Learn about unconventional ways to clean up crude oil, including using moss and chickens

Studies show that microorganisms in chicken manure can break down the hydrocarbons in crude oil without producing toxic by-products. Scientists have also explored avoiding the environmental risks of chemical dispersants and synthetic adsorbents by using human hair and peat moss to adsorb crude oil, which can be taken up by their cuticles and porous structures, respectively.

Scientists determine the smells of objects in outer space

Using spectrographic techniques, scientists determine the chemical composition of planetary atmospheres, comets, and other objects in space. Combining these chemicals in labs on Earth has revealed locations in space that smell like nail polish remover, rotten fish, and urine.

Why bacterial bioremediation may help counter the negative effects of past chemical solutions

Molecules such as DDT, a synthetic insecticide, and PFAS—"forever" chemicals used to make products resistant to heat, water, and grease—have historically been used across various industries but are now known to be harmful. Microbes that can convert some of these substances into nontoxic products, such as water and carbon dioxide, have already been identified, with ongoing research to find others.

A 'fishy' scent does lead to mistrust

In experiments where people were exposed to a literal fishy smell they were less willing to cooperate with others in economic games requiring trust, but that wasn't the case when they were exposed to another bad odor—the smell of flatulence.

Dogs smell a lot of stuff we can't, including bed bugs and chemicals in electronic devices

In addition to identifying medical smells and tiny insects like bed bugs, dogs can also detect electronic storage devices. These tools often contain triphenylphosphine oxide, a chemical used to prevent overheating.

'Old people' smell is real—it's a chemical buildup when fatty acids on the skin oxidize

The chemical composition of body odor seems to change with age. Later in life, we harbor higher concentrations of a chemical compound called 2-nonenal that forms when omega-7 fatty acids on the skin oxidize, and the skin's natural antioxidant defenses weaken. Commonly called "nonenal", it's the smell widely associated with aging, and it's often described as a grassy or greasy odor.

Scientists seeking gut insights are attaching flatulence sensors to volunteers' underwear

This fart-tracking device detects gas generated in the gut, providing insights about gut microbial activity. The underwear sensors measure a component of what is technically called flatus—digestive system gas.

A stand-in 'nose' may help people with anosmia to smell certain odors

In a 2025 paper, researchers reported they'd created a proof-of-concept device that bypasses typical olfactory pathways and instead exploits an alternative—the trigeminal nerve in the nose—to detect a few strong scents. The nerve typically helps detect the temperature of inhaled air or the presence of irritants. (Some users may experience a paywall.)

Deep sea fish rely on a molecular strengthener to prevent being crushed

Trimethylamine N-oxide (TMAO) stabilizes hydrogen bonds and prevents water and proteins within organisms from being misshapen under immense pressure. Compounds called piezolytes protect cellular membranes from being crushed in regions like the Mariana Trench, where pressures are 1,100 times greater than surface atmospheric pressure.

Synthetic pheromones may protect coral reefs by attracting their predators

Researchers in Australia and Japan have developed these nontoxic chemicals to attract crown-of-thorns starfish, which consume corals that make up the Great Barrier Reef. As of 2026, synthetic pheromones have been shown to be effective in lab trials, and future field trials will attempt to lure starfish into areas for mass removal.

Explore some of the trademarked scents in the US

Scents, when they are truly unique and identifiable to a particular brand, can be trademarked. Any trademark on a scent must pass two tests: distinctiveness and non-functionality. In order to be trademarked, the scent of a product can't be the primary purpose of that product (like a candle or a perfume), and the scent has to be distinct. Some of the trademarked scents include Play-Doh and the pain-relief patch Salonpas.

Some animals possess sensitive hearing to help pinpoint prey and map the world

Bats and dolphins produce sound to reflect off surfaces and create a mental image of their surroundings. Owls' faces are dish-shaped to help funnel sounds to their ears, including that of mice moving along leaves or snow. Pinnipeds, such as seals and walruses, hear in both air and water.

A collection of molecular gastronomy techniques, from flavored air to turning oils into powder

Soy lecithin can be blended with flavored mixtures, such as herbs and Parmesan, to produce edible bubbles, which can be frozen into a solid foam. Maltodextrin can be combined with liquid fats in a food processor to create light, flavorful powders.

Carbon sinks absorb more greenhouse gases than they produce

The largest on Earth are oceans, which capture 25% of all carbon emissions and 90% of excess atmospheric thermal radiation while generating half of the world's oxygen. Wildfires and deforestation have reduced forests' net sink capacity, though fungi are believed to capture and store over a third of global carbon emissions.

Exposing fetuses to certain flavors in the womb could lead to children being less picky eaters

A new study found that 3-year-olds were less averse to the smell of vegetables they had been repeatedly exposed to in utero, suggesting that what mothers eat in late pregnancy can leave a lasting imprint on their children's tastes.

Bacteria use chemical signals to communicate and coordinate with one another

Through a system called quorum sensing, bacteria produce and absorb compounds from their environment to identify allies or competitors and adjust their behavior accordingly. Some bacteria produce food-digesting enzymes only in the presence of similar bacteria, thereby preventing competitors from consuming their meal.

Anesthetics slow brain activity by promoting inhibitory neurotransmitters

Drugs like propofol and isoflurane increase activity at the GABA receptor, which opens chloride channels. These ions enter neurons and hyperpolarize them, making them less likely to fire. Dexmedetomidine instead blocks norepinephrine receptors in the brainstem to sedate patients.

Fecal transplants can help treat infections

Fecal transplants aim to transplant healthy gut bacteria into ill patients by transferring (literally) samples of human waste from a healthy patient to a sick patient. The technique has been shown to cure otherwise deadly Clostridioides difficile (C. diff) infections and is being studied for a range of other uses.

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.

Why water is the universal solvent, despite not being good at dissolving many substances

Because oxygen attracts electrons much more strongly than hydrogen does in H₂O, the molecule is polar, with a negative charge at the oxygen atom and positive charges at the hydrogen atoms. These charged regions can attract and pull apart charged portions of other polar molecules, such as washable inks, but are unable to dissolve nonpolar materials, such as glass and asphalt.

How sunlight helps chlorofluorocarbons destroy the ozone molecules that block solar radiation

CFCs, which are used in old refrigerants, air conditioners, and aerosol sprays, do not react with atmospheric molecules. Once they reach the stratosphere, ultraviolet radiation breaks chlorine atoms off of them, which can each break apart more than 100,000 ozone molecules, thinning Earth's protective layer against ultraviolet radiation.

Antiperspirants work better if they are applied at night

Dermatologists recommend applying antiperspirant at night for the best results. When applied to clean, dry skin at night, the active ingredient in most antiperspirants (aluminum salt), combined with the skin's natural moisture, forms plugs that block sweat glands, limiting sweat and related odors.

Without liver bile, human poop would be a pale silver color

Stomach acid and enzymes break down food into smaller particles, expelling a semi-fluid mass called chyme into the small intestine, where bile is added. As the intestines absorb nutrients and water, the chyme solidifies and changes color.

View the rainbow effect on the waters at First Landing State Park

The phenomenon results from light interacting with a thin film of natural oils on the surface of swamps and marshes at the site, not unlike the coloration seen in soap bubbles. The oils originate from decaying vegetation or from anaerobic bacteria reducing iron in soil. (Some readers may experience a paywall.)

How slugs helped soldiers during WWI

Slimy, squishy, slow-moving, and heroic? Slugs are land-dwelling mollusks known mostly for causing havoc in our gardens. But during World War I, slugs saved numerous soldier's lives as poison gas detectors. Learn how the unpleasant creatures earned their stripes in the battle to protect soldiers from chlorine, phosgene, and mustard gas as organic detectors.

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.

Fish populations in the Great Barrier Reef have increased after installing waterproof speakers on the ocean floor that played recordings of sounds from healthy coral reefs.

Watch how deep-sea mining equipment collects and processes polymetallic nodules—metal-rich, potato-shaped rocks—from the ocean floor and creates environmentally damaging plumes of sediments.

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

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.

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

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.

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.

The price of gas is a composite made up of several different factors, with the federal gas tax making up less than 20% of what drivers pay at the pump.

When a Paris department store hesitated to sell Estée Lauder's perfume, she 'accidentally' broke a bottle, causing the smell to spread throughout the store and shoppers to start asking to buy the scent.

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

Learn how monoclonal antibodies, which mimic the body's antibodies, can fight diseases like Ebola.

Against his wishes, Albert Einstein's brain was removed before his cremation, and the pathologist responsible stored it for decades in mason jars within a beer cooler.

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

When you complete a CAPTCHA on a website to prove you are human, you may be unknowingly training algorithms for self-driving cars, whose systems require training data to help identify crosswalks, bicycles, and other outdoor objects.

SpongeBob exemplifies Aristotle's philosophy for living well because he understands that happiness doesn't come from external factors like money, recognition, or power.

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

Power lines are dotted with large, brightly colored balls to improve the visibility of these thin wires to helicopters and small planes and help prevent potential crashes.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

Learn how to read a prospectus, the juicy document that any company must file with the SEC before going public.

To reduce wrinkles in clothing, research recommends gentle wash cycles with more water and tumble drying with smaller loads and longer times.

Explore fun facts from the USPS, including unique post office buildings, a stamp that traveled past Pluto, and more.

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