Urban Gardens, Natural Carpeting and Propane Tanks

How much do urban gardens contribute to our food supply?

—Wayne Chow, New York, NY

The United Nations Development Program estimates that urban gardens, like the ones springing up all over New York City and Seattle, provide 15 percent of the world's food supply. They also create sorely needed jobs in neglected neighborhoods and introduce concrete-raised children to the wonders of nature. Gardens bolster community pride and eliminate some of the environmental problems of modern agribusiness, including heavy use of pesticides and pollution from long-distance transportation.

Town planners, who may worry that constituents will be offended by manure and dirt, often view urban agriculture suspiciously. However, there are many examples of successful urban gardens. Hong Kong, one of the world's most densely populated cities, produces about half of its vegetables in urban gardens. In Moscow, nearly 65 percent of families engage in some kind of food production. In Havana, Cuba, urban gardens also play a crucial role.South Central Los Angeles" "Food from the "Hood" program provides college funds for the high school students who maintain organic gardens. San Francisco's Fresh Start Farms employs homeless families to grow produce for local restaurants. Even some U.S. prisons have now started urban gardens, which can be on rooftops as well as on the ground. CONTACT: Food from the "Hood, (888)601-FOOD, www.foodfromthehood.com; Fresh Start Farms, (415)487-9778, www.grassroots.org/usa/fresh.shtml.

—Katherine Kerlin

Are there any natural carpets that don't produce the strong odors and health concerns of conventional synthetic materials?

—Denise Purdy, via e-mail

Carpets made from all-natural materials are now readily available. Companies such as Earth Weave and Natural Home boast attractive carpets that are entirely biodegradable and are made of wool, jute, hemp and rubber and are free of dye and moth-proofing or stain-repellant chemicals.

These carpets are becoming more popular in part because there are, on average, 120 chemicals in each new piece of synthetic carpet, including the adhesive. Many of these chemicals are suspected or known carcinogens, such as formaldehyde. According to a spokesperson for Antibody Assay Laboratories, which provides services to health care providers, "These chemicals off-gas into the environment, polluting indoor air with volatile organic compounds (VOCs) that can create symptoms from itchy eyes to shortness of breath, headaches and nausea."

If you must install new synthetic carpet, there are a number of ways to make the situation more comfortable. Make sure you air the carpet out well before putting it in place. Consider using less-toxic installation techniques such as the TacFast system, a hoop-and-loop method similar to Velcro that eliminates the need for liquid adhesives. You can also use products that decrease carpet toxicity, such as AFM Enterprises" CarpetGuard. CONTACT: AFM Enterprises, (619)239-0321, www.afmsafecoat. com; Earth Weave, (706)278-8200, www. earthweave.com; Natural Home, (707) 824-0914, www.naturalhomeproducts.com.

—Laura Ruth Zandstra

How can I recycle my old propane gas tank that can no longer be refilled?

—Bruce Krasnow, Santa Fe, NM

If you have an older propane gas tank that has been denied refilling by retailers, it is probably because it lacks an Overfilling Prevention Device (OPD). As of April 2002, the National Fire Protection Agency's (NFPA) safety code requires an OPD on every propane tank that holds between four and 40 pounds of the gas, which includes tanks normally used for grills, RVs and other devices. An OPD is part of the valve and is designed to prevent spills and release of gas during heating, which can lead to fires and injuries. All tanks produced after September 1998 are equipped with these devices. "Old propane tanks have hand wheels that are round or star shaped, while new tanks have triangular wheels with the OPD stamp," says the NFPA.

For a fee, you can take your old tank to a propane dealer for retrofitting with a new valve. You can also pay a fee and exchange your old tank for a new one. If you've already purchased a new unit, or don't need to use propane anymore, there are a number of ways to recycle the old cylinders. Some dealers are able to refurbish and reuse old tanks. If all else fails, the cylinders can be recycled as scrap metal at your local metal yard. CONTACT: NFPA, (617)770-3000, www.nfpa.org.