current issue web exclusives blog multimedia archive subscribe advertisers
Feature Articles
Editor's Note
Audubon View
Field Notes
Green Guru
Citizen Science
Earth Almanac
One Picture

Green Guru
Advice for the eco-minded.


Are all jellyfish poisonous? What should I do if I get stung by one?
—Jane McMahon, Fort Lauderdale, FL

Those gelatinous, undulating creatures we call jellyfish all produce at least some toxin, but not every species is dangerous to humans.

There are a couple thousand varieties worldwide, from small sea nettles to large moon jellies, and the severity of their stings varies. A handful are deadly.

Some of the most dangerous are box jellyfish, which have 10-foot tentacles and the planet’s most potent venom. (They are found mostly in waters off the coast of Australia.) By contrast, others, like cannonball jellies—tennis- to soccer-ball sized blobs that have a reddish-brown pattern and live primarily in the Gulf of Mexico—don’t usually affect humans.

No matter the size or toxicity, jellyfish are crucial to ocean health. “In spite of the fact that when their numbers are high they’re often considered a nuisance, in many areas they’re actually an important part of the natural ecosystem,” says Denise Breitburg, a scientist at the Smithsonian Estuarine Research Center. They use their venom to kill or paralyze prey—usually zooplankton and small fish—and help to keep those populations in check.

If a jellyfish stings you, get out of the water and ever so carefully remove the tentacles with a towel or sand (or anything other than your hand, to prevent further stinging). Contrary to popular belief, peeing on the area won’t relieve the burn. Instead, try to soothe the pain with vinegar or a paste made of baking soda, and see a doctor if you feel sick. The next time you hit the waves, take the sting out of your day at the beach by appreciating those translucent swimmers from a distance.
Back to Top


My hybrid car gets good mileage, and I feel green about this. But what about the energy used in manufacturing the batteries? And how are those batteries recycled or disposed of?
—D.D. Trent, Claremont, CA

Hybrid cars are fuel-efficient, emit fewer greenhouse gases than the average auto, and perform well.

Life-cycle analyses of hybrids conducted by the Massachusetts Institute of Technology and Argonne National Laboratories show that producing nickel-metal hydride batteries, the ones used in these cars, is up to three times more energy-intensive than manufacturing conventional car batteries. That disadvantage, however, is quickly made up for once the hybrids hit the road.

If you look at what a car is made of to how it’s disposed of, “you want the advanced battery when it comes to environmental impact,” says Laura Schewel, a consultant at the Rocky Mountain Institute.

The main component of nickel-metal hydride batteries is—you guessed it—nickel, an element mined from reserves in Russia, Canada, and southwest Africa. Extracting the resource is environmentally damaging, like all mining operations. Most companies that make hybrid cars recycle the batteries, and up to 100 percent of the nickel can be recovered, according to Toyota (whose “concept” Prius is shown above).

New plug-in hybrids will most likely use lithium-ion batteries, which are lighter and last longer than nickel-metal hydrides. Plus lithium mining is less intensive than nickel mining. These batteries may even have a usefulness beyond automotives. “They will still have a lot of life for stationary applications, like solar power storage,” says Mohamed Alamgir of Compact Power, the company General Motors just chose to supply batteries for the Chevy Volt. Companies are working with recycling businesses to ensure that the lithium is recovered. So you can continue to feel good about your hybrid. And get a charge from what’s on the road ahead.
Back to Top


Is there really such a thing as “clean coal”?
—Peter Lafferty, Peoria, IL

Coal is dirtier than dirt. Used to generate more than half of our electricity, this fossil fuel is the biggest source of air pollution in the United States. Burning coal emits harmful chemicals, including nitrous oxide and sulfur dioxide, two compounds that cause acid rain. Smokestacks also belch particulates, mercury, and that pervasive greenhouse gas, carbon dioxide.

Although clean coal doesn’t have a standard definition, some companies and politicians, including President Obama, tout the term. Others, like Al Gore, say it’s an oxymoron. This much is true: Improved combustion technologies make burning coal a much cleaner process than it was two decades ago. The Clean Air Act and other laws have also reduced environmental harm by requiring companies to scrub some pollutants from emissions.

However, other toxins, like mercury, which is known to cause developmental and neurological problems in wildlife and children, remain a significant problem, and more than 40 percent of mercury in the air comes from coal. The good news: The Obama administration has announced plans for more stringent mercury emission standards for power plants.

Today the focus is on removing carbon dioxide from coal-fired power plant emissions. “That’s become the new motto of a clean coal plant,” says Howard Herzog, director of MIT’s carbon sequestration program. (For more on sequestration, see “Get Down”.) It will take legislation to make large-scale sequestration economically feasible, says Herzog.

Now that would be truly groundbreaking.
Back to Top

Send your most vexing questions to