A: It sure would be nice if we could obtain all of our food and drink items from local sources, but sugar provides an excellent example of why such a desire may remain a pipe dream in the United States for a long time to come.

The sugar we consume that is produced domestically comes from sugar cane grown in Hawaii and the Southeast and sugar beets from the Upper Midwest, Pacific Northwest, California and elsewhere. However, it is likely milled and refined hundreds if not thousands of miles from where it is harvested, and then shipped all over the country - causing untold greenhouse gas emissions - in various-size packages for consumption in our coffee, on our cereal and, for some of us, in our cocktails.

Massive government subsidies and land giveaways to the sugar industry in the American Southeast beginning in the early 18th century established a market for American-grown sugar despite the fact that the region's climate was not tropical enough to grow cane efficiently. To add insult to injury, the rerouting of southern Florida's fragile water table to irrigate thirsty sugar plantations contributed to the decimation of the Everglades, one of the nation's most unique and diverse ecosystems - and now the subject of a multibillion-dollar restoration effort.

While you might be hard-pressed to find commercially available local sugar anywhere in the U.S., you could make your own.

"Years ago, when sugar was an expensive commodity, many people of lesser means made their own sugar from sugar beets," reports writer Kat Yares on the eHow.com website. "Every farm and every home garden had a spot reserved for beets, and a day was set aside to cook the beets down into sugar."

While very few of us grow our own food these days, growing sugar beets and making sugar from scratch can be a fun, educational and tasty project for parents and kids or for foodies intent on local, preservative-free ingredients.

If that sounds like too much work, perhaps you can settle for store-bought organic sugar, which may not be local but which is at least produced without chemical pesticides and fertilizers. Florida Crystals, Hain, C&H, Domino and others each offer organic sugar varieties in many traditional grocery stores coast to coast. Believe it or not, there are even vegan sugars out there - that is, sugars not processed with animal-derived bone char in the refinement process.

While sugar itself may be a staple item for many cocktails, some interesting alternative natural sweeteners, some of which may be locally sourced in your region, do exist. Agave nectar, honey or even maple syrup are some options that might just give that Tom Collins the extra kick it needs to make it stand out from the other bartender's drinks down the street - or in your breakfast cereal, for that matter.

Send your environmental questions to: EarthTalk, c/o E - The Environmental Magazine, P.O. Box 5098, Westport, CT 06881; earthtalk@emagazine.com. E is a nonprofit publication.

A: It's impossible to pin isolated natural phenomena - like an individual volcanic eruption - on global warming, but some researchers insist that there is a correlation between the two in some instances.

"Global warming melts ice, and this can influence magmatic systems," said Freysteinn Sigmundsson of the Nordic Volcanological Centre at the University of Iceland.

Her research with Carolina Pagli of the University of Leeds in England suggests that rocks cannot expand to turn into magma - the primary "feedstock" for volcanic eruptions - when they are under the pressure of a big ice cap pushing down on them. As the theory goes, melting ice caps relieve that pressure and allow the rocks to become magma. This in turn increases the chances of larger or more frequent eruptions in affected regions, from Iceland to Alaska to Patagonia to Antarctica.

As for Iceland specifically, the eruption of Mount Ejyafjallajökull that shut down some air travel for weeks in the spring cannot be blamed on changing climate: That volcano lies under a relatively small icecap that would not exert enough pressure to affect the creation of magma.

But Dr. Sigmundsson and Dr. Pagli found that the melting of about a tenth of Iceland's biggest icecap, Vatnajokull, over the last century caused the land to rise an inch or so per year and led to the growth of an underground mass of magma measuring a third of a cubic mile. Similar processes, they say, led to a surge in volcanic eruptions in Iceland at the end of the last ice age. Similarly, increased volcanic activity is expected to occur there in the future.

On the flip side, volcanic eruptions can exacerbate the ongoing effects of climate change: Retreating glaciers can lose all their ice when something below them blows. Of course, many volcanoes around the world are not subject to pressure from ice caps, and scientists stress that there is little if any evidence linking global warming to eruptions in such situations.

Some have theorized that large volcanic eruptions contribute to global warming by spewing large amounts of carbon dioxide and other greenhouse gases into the stratosphere. But the amount of greenhouse gases emitted by even a large and ongoing volcanic eruption is but a drop in the bucket in comparison to our annual output of industrial and automotive carbon emissions. According to the U.S. Geological Survey, greenhouse gas emissions from volcanoes make up less that 1 percent of those generated by human endeavors.

Also, ash clouds and sulfur dioxide released from volcanoes shield some sunlight from reaching the Earth and as such can have a cooling effect on the planet. The 1991 eruption of Mount Pinatubo in the Philippines - a much larger eruption than what occurred recently in Iceland - caused an average cooling of half a degree centigrade worldwide during the following year. Regardless, single volcanic eruptions, even if they last for weeks or months, are unlikely to send enough gas or ash into the skies to have any long-term effect on the planet's climate.

Send your environmental questions to: EarthTalk, c/o E - The Environmental Magazine, P.O. Box 5098, Westport, CT 06881; earthtalk@emagazine.com. E is a nonprofit publication.

A: Triclosan is a synthetic chemical compound added to many personal and household care products to inhibit illness by preventing bacterial infection.

It works by breaking down the biochemical pathways that bacteria use to keep their cell walls intact, and as such kills potentially harmful germs if used in strong-enough formulations.

First developed as a surgical scrub back in 1972, triclosan is now used in upward of 700 different consumer-oriented products, many of which people use more than once a day. They include hand soaps, deodorants, toothpastes, kids' toys, yoga mats and, of course, hand sanitizers.

Whether triclosan is actually as effective as advertised, especially in the small doses found in consumer products, is a topic of much debate. Manufacturers insist that the product helps reduce infections. But researchers from the University of Michigan's School of Public Health found, after surveying 27 different studies conducted between 1980 and 2006 on the effectiveness of antibacterial soaps, that washing hands with products containing triclosan was no more effective in preventing infectious illness - and did not remove any more bacteria - than plain soaps.

The analysis, "Consumer Antibacterial Soaps: Effective or Just Risky?" was published in 2007 in the peer-reviewed journal Clinical Infectious Diseases. According to lead researcher Allison Aiello, triclosan - because of the way it reacts in living cells - may cause some bacteria exposed to it to become resistant to amoxicillin and other commonly used antibacterial drugs. But she adds that more research is needed to bear out this hypothesis.

Anti-bacterial soaps and other products with triclosan may in fact be doing more harm than good for the people who use it regularly. According to the nonprofit Beyond Pesticides, triclosan has been linked to various human health problems.

"It is associated with skin irritation, has been shown to interfere with the body's hormones, and has been linked to an increased risk of developing respiratory illness or asthma, and cancer, as well as subtle effects on learning ability," reports the group, adding that 75 percent of Americans are walking around today with trace levels of triclosan in their bloodstreams.

Tests using lab animals have verified that exposure to large doses of triclosan can cause irreparable health damage, but industry representatives say the levels found in consumer products are much too small to do so.

Beyond its potential human health effects, triclosan also can harm the environment. According to Beyond Pesticides, some 96 percent of the triclosan from consumer products is washed down drains, where it flows into wastewater treatment plants often ill-equipped to deal with it. Inevitably some of the triclosan escapes treatment and is released into waterways, where exposure to sunlight can convert it into dioxins, a highly toxic group of chemicals responsible for contaminating waterways and wreaking havoc on wildlife.

The U.S. Food and Drug Administration is finally taking a fresh look at triclosan after years of controversy.

Send your environmental questions to: EarthTalk, c/o E - The Environmental Magazine, P.O. Box 5098, Westport, CT 06881; earthtalk@emagazine.com. E is a nonprofit publication.