sustainability

Organic substances “biodegrade” when they are broken down by other living organisms (such as enzymes and microbes) into their constituent parts, and in turn recycled by nature as the building blocks for new life. The process can occur aerobically (with the aid of oxygen) or anaerobically (without oxygen). Substances break down much faster under aerobic conditions, as oxygen helps break the molecules apart.
Most landfills are fundamentally anaerobic because they are compacted so tightly and thus do not let much air in. As such, any biodegradation that does take place does so very slowly. “Typically in landfills, there’s not much dirt, very little oxygen, and few if any microorganisms,” says green consumer advocate and author Debra Lynn Dadd. She cites a landfill study conducted by University of Arizona researchers that uncovered still-recognizable 25-year-old hot dogs, corncobs and grapes in landfills, as well as 50-year-old newspapers that were still readable.
Biodegradable items also may not break down in landfills if the industrial processing they went through prior to their useful days converted them into forms unrecognizable by the microbes and enzymes that facilitate biodegradation. A typical example is petroleum, which biodegrades easily and quickly in its original form, crude oil. But when petroleum is processed into plastic, it is no longer biodegradable, and as such can clog up landfills indefinitely.
Some manufacturers make claims that their products are photodegradable, which means that they will biodegrade when exposed to sunlight. A popular example is the plastic “polybag” in which many magazines now arrive protected in the mail. But the likelihood that such items will be exposed to sunlight while buried dozens of feet deep in a landfill is little to none. And if they do biodegrade at all, it is only likely to be into smaller pieces of plastic.
Some landfills are now being designed to promote biodegradation through the injection of water, oxygen, and even microbes. But these kinds of facilities are costly to create and as a result have not caught on. Another recent development involves landfills that have separate sections for compostable materials, such as food scraps and yard waste. Some analysts believe that as much as 65 percent of the waste currently sent to landfills in North America consists of such “biomass” that biodegrades rapidly and could generate a new income stream for landfills, marketable soil.
But getting people to sort their trash accordingly is another matter entirely. Indeed, paying heed to the importance of the environment’s “Three Rs” (Reduce, Reuse, Recycle!) is likely the best approach to solving the problems caused by our ever-growing piles of trash. With landfills around the world reaching capacity, technological fixes are not likely to make our waste disposal problems go away.

CONTACTS: U.S. Environmental Protection Agency (EPA) Reduce-Reuse-Recycle page; www.epa.gov/epaoswer/non-hw/muncpl/reduce.htm.

Dear EarthTalk: In what ways is global warming already affecting us in North America?

— Tyler Merson, New York, NY

There are many examples of climate change’s real and present impact. For one, the 20 hottest years since record keeping began in the 1880s have all occurred since 1983, and until this year 2005 was the hottest year ever. Now, according to a new U.S. climate report, 2006 is well on its way to taking the top spot.
If you like New England’s maple syrup, you’ll be dismayed to know that producers report seeing global warming’s effect on their seasonal harvesting cycles. Farmers are tapping their trees a month earlier than their ancestors did, and some fear that global warming will eventually reduce the trees’ ability to produce high-quality sap. “I think the sugar maple industry is on its way out,” says University of New Hampshire professor Barrett Rock, who led research on regional risks related to climate change.
Some ski resorts in the Pacific Northwest blame global warming for the warm weather that shut down the 2004-2005 season before it even began. University of Washington professor of atmospheric sciences Cliff Mass reports that less snow has been falling in Washington State for the last 20 years. “Global warming is occurring,” he concludes. Also in trouble due to declining snow are New England and Midwestern resorts.
The loss of sandy beaches due to climate-aggravated sea level rises is also troubling, and the problem is accelerating. The National Science Foundation’s Metro East Coast report says that beach erosion will likely double by the 2020s, increase from three- to six-fold by the 2050s and by as much as 10-fold by the 2080s. Already, sand loss has led to large beach replenishment efforts by the Army Corps of Engineers.
And keep plenty of calamine lotion on hand. Researchers at Duke University found that some vines—including poison ivy—may thrive exponentially in a warmer climate. Experiments showed that poison ivy growing in a carbon dioxide-rich environment grew about three times larger than normal and produced significantly more urushiol, the allergenic substance that causes rashes.
Another indicator of increased warming is the retreat of glaciers across western North America. This troubling phenomenon is especially noticeable in the Waterton-Glacier park complex on the U.S.-Canada border. Several major glaciers there have shrunk by half or more in recent decades. On the U.S. side of the border, the number of glaciers in Glacier National Park has dropped from 150 in 1850 to 35 today.
Wildlife is also feeling the heat. A 2004 study by the Wildlife Society, a 9,000-member group of wildlife professionals, found that global warming is affecting many North American species and could cause major shifts in ecosystems. The group concluded that caribou, polar bears, migratory songbirds and other species have already responded to climate change by shifting habitat, altering their breeding patterns or changing their migration routes.
Finally, stronger storms like Hurricane Katrina in recent years may be partially explained by global warming. Researchers have found that both the intensity and number of category 4 and 5 storms have greatly increased in the past 35 years, and have linked that phenomenon to warming ocean temperatures.

CONTACT: Intergovernmental Panel on Climate Change, www.ipcc.ch.

Dear EarthTalk: I heard that Coca-Cola is depleting ground water around bottling plants in India so surrounding villages have no safe water supply? Is this true?

—Dan Ehl, Centerville, IA

An ongoing drought has threatened groundwater supplies across India, and many villagers in rural areas are blaming Coca-Cola for aggravating the problem. Coke operates 52 water-intensive bottling plants in India. In the southern Indian village of Plachimada in Kerala state, for example, persistent droughts have dried up local wells, forcing many residents to rely on water supplies trucked in daily by the government.
Some there link the dry wells to the arrival of a Coca-Cola bottling plant in the area three years ago. Following several large protests, the local government revoked Coca-Cola’s license to operate last year, and ordered the company to shut down its $25 million plant.
Similar problems have plagued the company in the rural Indian state of Uttar Pradesh, where farming is the primary industry. Several thousand residents took part in a 10-day march in 2004 between two Coca-Cola bottling plants thought to be depleting groundwater. “Drinking Coke is like drinking farmer’s blood in India,” said protest organizer Nandlal Master. “Coca-Cola is creating thirst in India, and is directly responsible for the loss of livelihood and even hunger for thousands of people across India,” added Master, who represents the India Resource Center in the campaign against Coca-Cola.
Indeed, one report, in the daily newspaper Mathrubhumi, described local women having to travel five kilometers (three miles) to obtain drinkable water, during which time soft drinks would come out of the Coca-Cola plant by the truckload.
Water isn’t the only issue. The Central Pollution Control Board of India found in 2003 that sludge from the Uttar Pradesh factory was contaminated with high levels of cadmium, lead and chromium. To make matters worse, Coke was offloading cadmium-laden waste sludge as “free fertilizer” to tribal farmers who live near the plant, prompting questions as to why they would do that but not provide clean water to local residents whose underground supplies were being “stolen.”
Another Indian nonprofit group, the Centre for Science and Environment (CSE), says it tested 57 carbonated beverages made by Coca-Cola and Pepsi at 25 bottling plants and found a “cocktail of between three to five different pesticides in all samples.” CSE Director Sunita Narain, winner of the 2005 Stockholm Water Prize, described the group’s findings as “a grave public health scandal.”
For its part, Coca-Cola says that “a small number of politically motivated groups” are going after the company “for the furtherance of their own anti-multinational agenda.” It denies that its actions in India have contributed to depleting local aquifers, and calls allegations “without any scientific basis.”

CONTACTS: India Resource Center, www.indiaresource.org; Coca-Cola India, www.coca-colaindia.com.

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