Air pollution may be responsible for more than 2 million deaths around the world each year.

Outdoor air pollution has now been classified as 'carcinogenic to humans' by the United Nations.

Tokyo, which cleaned up its act in the 1970s, is a role model as the Chinese capital starts to address some of the world's worst air pollution.

Four cinder blocks + one minute of time = wonderfully functional rocket stove.

Yes, you read that right.

Loopholes in the Montreal Protocol may need to be tightened, researchers say.

Air pollution exposure contributes to one in eight deaths around the globe, according to WHO estimates.

Electronics giant announces it will compensate workers relocating to China for the poor quality of air they will have to breathe.

Skeptics question whether China can grow its economy and fight emissions. The truth is, it has no choice.

A new report from the American Lung Association finds that nearly 148 million Americans breathe unhealthy air.

A new study by WHO finds that air pollution has worsened since 2011, signaling increased health risks for city dwellers.

Chilean soccer fans are urged do the unthinkable and kindly step away from their grills due to worsening air quality levels in Santiago.

Oregon's Silver Falls State Park is a wonderland of rivers, streams, rainforest and cascading water.

Dozens of cities throughout the country have either banned or limited fireworks displays due to the threat of heavy pollution.

The soot that covers statues and buildings makes even more smog, eventually hitting our lungs.

PVC puts out a lot of nasty stuff when it burns, and it's probably still in the soot.

A new study says commuting to work by car may be far more harmful to your health than previously believed.

China's most polluted cities have made strides in reducing air pollution, but there's still work to be done.

Preference for "cleaner" male trees and plants in urban settings may trigger extra sneezing and wheezing. That's botanical sexism, says Thomas Ogren.

This is what London's air would look like without cars.

Some cities outside the U.S. are banning school drop-offs by car. They say it saves time — and lives.

The air inside your home can be more polluted than the air outside. Want cleaner air? Here are 11 natural ways to clean your indoor air without using chemicals.

A 'capped inversion' trapped air pollutants near the ground.

Falling levels of air pollution have resulted in a drop in California's dense tule fog.

Meet 15 rare animal species whose futures could be determined — for better or worse — in 2015.

Re-wilding nature is always controversial, as evidenced by the conflicting views in North Carolina over the reintroduction of the red wolf.

Sudan and two females of his subspecies are under constant surveillance in Kenya, but it may not be enough to save the northern white rhino from extinction.

Biologists map Earth's mammal diversity in a parallel universe without human civilization.

Here's a graphical glimpse at America's most endangered wildlife, where they live and how many are left.

Seeds found during an archaeological dig on First Nations land revive a long-lost varietal.

Just like 'Jurassic Park,' except with flowers instead of dinosaurs.

Mankind does some weird things to save animals from extinction.

Researchers have launched a mission to find the Javan fishing cat, the rarest cat in the world.

The discovery offers new insights about dinosaur plumage, hinting at a 'chestnut brown' creature that couldn't fly.

Some of these massive beasts are familiar in form but enormous in size, while others are strange hybrids of modern-day animals.

New study from Australia suggests resurrection of extinct species could lead to a loss in overall biodiversity.

The sun, like many stars, may be a binary, meaning it could have a mass-extinction-causing 'brother.'

At least five similar die-offs have happened before, but this is the first in human history — and the first with human help.

Even core areas of pika habitat 'are vulnerable to climate change within a timeframe of decades,' researchers say.

The giant bug, Lord Howe Island stick insect, was rediscovered in the early 2000s, and now scientists have confirmed it's in fact them.

Ancient 5-foot 7 penguin weighed at least 220 pounds and speared fish with its sizable beak.

Scientists identified the cause of the mystery die-off, as half of the species' population perished within a matter of weeks in 2015.

This is the first photograph ever taken of the bizarre and mysterious species, Thismia neptunis.

The Caribbean nation of Haiti was once lush with trees and the animals that lived there, but now only a few sections of primary forest remain.

Researchers study the genetic secrets of the world's last Pinta Island tortoise.

Researchers extract nuclei from a preserved woolly mammoth carcass, implant them into the egg cells of mice, and watch as the bits became animated.

Humans have driven almost 600 plant species extinct since 1750s and that number is likely much higher.

Zest up your holiday feast with these must-have sauces and spices.

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