Mr. Green's January 1, 2008, Mailbag

Mr. Green loves hearing from his readers, whether they think he's a green guru or an eco-idiot. Periodically, he'll post some of his favorite exchanges online. To join an ongoing debate—or start a new one—e-mail mr.green@sierraclub.org.

A Very, Very Hot Topic, or "I Miss My Lung, Bob"

Hey Mr. Green, In answering a question about the most ecofriendly way to feed a fireplace, you failed to mention the possibility of using a pellet stove. I own such a stove and have found it to be much easier to use and more efficient than a traditional wood-burning stove, but I have yet to see an article in Sierra that talks about this type of heat source. What say you? —David in Highland Park, New Jersey

Hey David,
Thanks for reminding me about wood-pellet stoves. They emit only one-fourth as much fine particulate matter (the tiny and dangerous particles in smoke that are less than ten micrometers in diameter) as EPA-approved stoves, so the agency doesn't even bother rating them. If you can't use oil or natural gas--or won't use them because you're a cantankerous, off-the-grid corporate-fuel hater or survivalist--the pellet stove is your cleanest choice. Also, the pellets are made of materials that might otherwise have been wasted. Still, even the cleanest-burning wood-pellet stove emits a lot more particulates than heating your home with gas or oil.

Thanks also for providing me with another opportunity to warn my wheezing fellow humans about the dangers of wood stoves: Despite the nostalgic image of families snuggling up in the glow of the hearth and listening to tales of bygone days, the old burners could more aptly be called "killer stoves" due to their emissions. The most dangerous of the microparticles are less than 2.5 micrometers, or about a 30th the size of a human hair. These can lodge deep in the lungs, damaging them and the circulatory system. Old stoves can emit up to 15 times more fine particles than ones made after the EPA tightened its regulations in 1988. On top of this, they require a lot more wood to make the same amount of heat.

In some areas, as much as 80 percent of the particulates in the air come from burning wood, when the weather favors such a buildup. Yet of the estimated 10 million wood stoves in the United States, only 20 to 30 percent are the newer, safer EPA-approved models. Therefore, the EPA has been setting up programs to get people to replace old stoves with new models; in some locations, you can even get a rebate for retiring your aged smogster. For more on this topic, check out the EPA's fact sheet on wood-burning efficiency and safety and its list of certified stove models.
Environmentally,
Mr. Green

Getting the Mercury Out: Part II of What Is Turning Into a Very, Very Long Series

Hey Mr. Green, Since we have been using mercury-containing fluorescents since the 1940s, the relevant question would seem to be whether it's easier to contain mercury released from a power plant or in our solid-waste stream? —Jerry in Jamaica, New York

Hey Jerry,
Yes, if done strictly, controlling emissions from power plants would clearly be the most effective way to bring about a large reduction in the amount of toxic mercury in our air and water. Around 48 tons of mercury are emitted each year from power plants in the United States. The EPA has announced a goal of cutting this down to 15 tons by 2018. However, the agency's plan involves a cap-and-trade system critics say will actually not reduce mercury in some areas at all, and almost two dozen states are working to pass their own stricter regulations.

Total human-caused mercury emissions in the United States have declined considerably, thanks to stiff regulations and changing technology. We're now emitting around 115 tons total annually, down from 220 tons in 1990. Emissions peaked at twice this level in the 1950s, when they were ten times higher than in the 19th century.

This is all very good news, the kind of news environmentalists ought to crow about more. (Seems to me that we sometimes get so caught up in dealing with new messes that we don't demand enough credit for cleaning up the old ones.) But we do have a problem with compact fluorescent lightbulbs, because no mercury is good mercury. What we need, in my opinion, is much clearer point-of-sale information and more-prominent information on bulb packaging about the dangers of mercury and the importance of recycling.

As I've noted before, if all home lighting used in the United States were fluorescent, the mercury in dead bulbs would add up to around four tons a year. (Of course, the enviros-are-sissies dudes are in such denial about environmental problems they'll tell you that's such a small part of the total it's not worth worrying about--then down a shot of mercury with a DDT chaser to prove their point.) But because a lot of total mercury emissions are made up of just such "small" parts--3.5 percent from cement plants, 4.5 percent from hazardous-waste incineration, etc.--we neglect any part at our cumulative peril.

Finally, although we know what a major environmental nuisance the United States is--the classic example being that with 5 percent of the world's population, we burn 25 percent of the world's oil--we're far less reckless with mercury, emitting about 2 to 3 percent of the world's whopping total of 4,400 to 7,500 tons a year. Unfortunately, this can't be dismissed as somebody else's issue, because mercury vapor and compounds can drift thousands of miles in the atmosphere. So when we buy imported goods made in countries with lax emissions standards, we might be poisoning ourselves and the unfortunate residents of those nations. Plus, when we ship tons of our worn-out, mercury-containing products overseas for recycling, we're offshoring pollution along with jobs. It's clear that the whole world needs strict limits on mercury.
Environmentally,
Mr. Green

Hey Mr. Green, Why is there air? —Anonymous

Ooo-wee, I just love these big questions. They remind me of those probed in Time magazine cover stories, like "Who Was Moses?" "Is Government Dead?" "Is God Dead?" "Is God Coming Back to Life?" (Verily, folks, thus hath Time spoken.) In the beginning, there was air, but not the marvelous kind in which we now exist. Go back 4 billion years, and the air was made up of assorted combinations of suffocating gases like carbon dioxide, methane, hydrogen sulfide, and nitrogen. Then, around 2 to 3 billion years ago, cyanobacteria (a.k.a. blue-green algae) figured out how to release oxygen by extracting it photosynthetically from carbon dioxide and water.

This was followed by the appearance of plants that produce oxygen, accelerating the 2-billion-year process in which the oxygen content in the atmosphere increased from close to nothing to the 20 percent level of today. Of course, there were all sorts of other complicated geological, chemical, and biological changes that cooperated in this development. Kinda makes you wonder about the arrogant polluters trying to undo this amazing atmospheric accomplishment--and the loopy zealots who deny that evolution ever happened. It's hard to say which group is more annoying: the former, who play God, or the latter, who claim to know exactly what He's been doing since the beginning of time.
Environmentally,
Mr. Green

Views expressed by readers may not reflect those of Mr. Green or Sierra magazine. Reader suggestions have not been researched or tested.

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Mr. Green illustration by Melinda Beck; used with permission.