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Pollution

Cattle are a major driver of methane emissions.

Why Do Cows Burp Up So Much Planet-Warming Methane? A Newly Discovered Structure in Their Gut Microbes Could Be a Culprit

The “hydrogenobody” is an organelle inside certain microorganisms that live in a special stomach chamber in cattle, sheep and goats, according to a new study

Western monarch butterflies bask in the sun on a eucalyptus branch at Lighthouse Field State Beach. In December 2025, researchers placed ultralight radio tags on some monarchs at this site, hoping to track their movements and identify areas to prioritize for the species’ conservation.

Butterflies Are in Dramatic Decline Across North America. A Close Look at the Western Monarch Shows Why

Pesticides, habitat loss and climate change have taken their toll on the beloved insects. But the experts working with them still find hope for their future

In experiments, juvenile Atlantic salmon that were exposed to cocaine’s primary metabolite swam more and dispersed farther than their sober peers.

Cocaine Pollution Seems to Make Salmon Swim Farther Than Usual. Scientists Don’t Know the Long-Term Consequences

The illegal drug’s main byproduct, benzoylecgonine, caused more robust effects than cocaine itself. Wastewater treatment plants often don’t fully process such metabolites, so they are frequently found in bodies of water at higher concentrations than their parent drugs

More than 95 percent of the world’s bergamot oil production is concentrated in Southern Italy’s Calabria region. But harsh conditions driven by climate change threaten that supply.

Earth’s Smells Are Disappearing Because of Climate Change, and It’s a Vast Cultural Loss

A triple threat of pollution, extinction and warming temperatures is altering the way the planet smells. Scientists are only beginning to understand the stakes for humans

Sharks in the Bahamas, including the Caribbean reef sharks, are ingesting drugs, a new study suggests.

Sharks in the Bahamas Test Positive for Drugs, Including Cocaine and Painkillers, in a New Study

Around one-third of the studied sharks had detectable levels of the analyzed drugs in their blood

Microplastics pose a growing global concern as they infiltrate not just the environment but also humans and animals.

This High School Student Invented a Filter That Eliminates 96 Percent of Microplastics From Drinking Water

Virginia teenager Mia Heller’s filtration system harnesses the power of ferrofluid, a magnetic oil that binds to microplastics in flowing water

The mural was unveiled in a suburb of San Salvador last month.

This Massive Mural Made From 100,000 Bottle Caps Is One Artist’s Reinterpretation of ‘The Mona Lisa’

Óscar Olivares, who is known for working with recycled materials, completed the 43-foot-tall artwork in Zacamil, El Salvador, in February

Swimmable Cities is a global alliance of local government officials, experts and advocates working to make urban waterways clean enough to swim in.

Would You Jump Into Your Local River? Swimmable Cities May Be Within Reach as Once-Polluted Waterways Are Restored

Efforts to improve the “swimmability” of urban areas are gaining global traction, from Paris to Chicago

Wetlands like South Sudan's Sudd swamp saw more rainfall in 2020 due to the La Niña climate event, which caused more methane to enter the atmosphere.

When Human Activity Dropped During Covid-19, Methane Levels Surprisingly Spiked. Now, a Study Points to Two Reasons Why

In a paradox of air pollution, a decrease in man-made pollutants led to more methane in our atmosphere. And natural wetlands released more of the planet-warming gas at the same time

After exposing an ant to the air pollutant ozone, its nestmates acted aggressively toward it.

Air Pollution Can Cause Some Ants to Turn on One Another—and Neglect Their Young, New Research Suggests

The findings further hint that air pollution, particularly ozone, is contributing to the “insect apocalypse”

Shenzhou-15 spacecraft debris streaked across the sky above California in April 2024. 

Sonic Booms and Earthquake Sensors Can Help Researchers Track Space Junk as It Plummets to Earth

Falling debris can travel at about 30 times the speed of sound, creating sonic booms that shake the ground

Gas stoves are responsible for more than half of some Americans’ total exposure to toxic nitrogen dioxide, a new study suggests.

Gas Stoves Are Poisoning Americans by Releasing Toxic Fumes Associated With Asthma and Lung Cancer

In the United States, gas stoves are the main source of indoor nitrogen dioxide—a toxic gas tied to many health problems—according to a new study

A dead tree stands with its bare, white trunk and branches in contrast to the greenery around it.

What’s Killing These Oak Trees in the Midwest? Conservationists Believe Drifting Herbicides Are to Blame

When Illinois landowners noticed tree deaths and diseases on their properties ramp up in 2017, they suspected industrial agriculture. A survey found herbicides in 90 percent of tree tissues

Research indicates that coral reefs have been tuning Earth's cycles for hundreds of millions of years. 

For More Than 250 Million Years, Coral Reefs Have Had a Major Influence on Earth’s Changing Climate

The planet has been flipping between two main modes of carbon recovery depending on the state of coral reefs, new research suggests

Seabirds are just some of the marine animals known to eat plastic. 

More Than 1,200 Marine Animal Species Eat Plastic. Ingesting Even a Tiny Amount Can Kill Them, a New Study Suggests

Researchers examined more than 10,000 animal autopsies to figure out how much plastic is too much for ocean wildlife

The Palos Verdes Kelp Forest Restoration Project near Los Angeles forms an ecosystem that is home to many creatures.

Underwater Forests Return to Life off the Coast of California, and That Might be Good News for the Entire Planet

Wondrous kelp beds harbor a complex ecosystem that’s teeming with life, cleaning the water and the atmosphere, and bringing new hope for the future

A Currier & Ives print, published in the mid- to late 19th century, depicts Crow’s Nest, a mountain along the Hudson’s west bank.

The History of America Flows Through the Hudson River, and the Country’s Aquatic Superhighway Is on the Rebound

The bucolic river is famous for reversing its current a few times each day. Now, an ongoing cleanup effort is reversing decades of industrial contamination

Gloria Acevedo, a diver with the Sirenas de Oriente in Mexico, removes a fishing line from coral near Cozumel Island.

‘Ghost Gear,’ or Abandoned Fishing Equipment, Is Haunting the Oceans. Here’s How Conservationists Are Fighting Back

Discarded nets, lines and traps are a hazard to marine life and ecosystems around the world, but pioneering programs are tackling the problem creatively through education, prevention, ocean cleanups and recycling

New research reveals that Earth's Northern Hemisphere is growing darker faster than the Southern Hemisphere is.

Earth Is Getting Dimmer—and the Northern Hemisphere Is Losing Brightness Faster Than Scientists Expected

New research challenges the idea that the hemispheres’ matching brightness is a fundamental property of the planet

New research suggests that the Salmon River in northwest Alaska is full of toxic metals.

Why Is This Remote and Rugged River in Alaska Turning Orange?

New research suggests the Salmon River is full of toxic metals that are likely harming fish and other aquatic creatures

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