Week of 1/25/2004

From the Editors of E/The Environmental Magazine

Dear EarthTalk: Can the mercury contained in some seafood harm a developing fetus?
—Midge Wilson, Utica, NY

Mercury—emitted by smokestacks and released to the environment from common household products like old thermometers—is a persistent heavy metal that ends up in rivers, lakes and oceans and accumulates in the tissues of fish and animals, including people. "Just one seventieth of a teaspoon of atmospheric mercury can contaminate a 20-acre lake for a year," says Michael Bender, executive director of the Vermont-based Mercury Policy Project.

According to a 2001 Centers for Disease Control and Prevention study, one in 10 American women of childbearing age is at risk for having a baby born with neurological problems due to mercury exposure—this means at least 375,000 babies a year are at risk.

Most states, and the U.S. Environmental Protection Agency, have issued advisories about eating fish that may have high levels of mercury in their tissues. The Food and Drug Administration (FDA) says that women can safely eat 12 ounces per week of cooked fish. A typical serving size of fish is from three to six ounces. However, the FDA advises pregnant and nursing women, and women of childbearing age who may become pregnant, to not eat shark, swordfish, king mackerel or tilefish, which contain high levels of methyl mercury.

In December 2003, the FDA released test results showing that the Albacore "white" canned tuna has three times the mercury levels as the "light" tuna. "FDA’s tests confirm earlier findings that white tuna has far more mercury than light," says Bender. "Yet inexplicitly, the FDA still refuses to warn women and kids to limit canned tuna consumption—like 12 states have already done—even after their food advisory committee recommended this over a year ago."

CONTACTS: Mercury Policy Project, 1420 North Street, Montpelier, VT 05602, (802) 223-9000, www.mercurypolicy.org; U.S. Environmental Protection Agency, Office of Water Science and Technology (4301T), 1200 Pennsylvania Avenue, NW, Washington, DC 20460, www.epa.gov/ost/fish/, ost.comments@epa.gov.


EARTH TALKFrom the Editors of E/The Environmental Magazine

Dear EarthTalk: What flooring materials reduce indoor air quality problems?
—Allen R. Linoski, Royal Oak, MI

According to the publishers of Environmental Building News, nearly 70 percent of American floors are covered in carpeting. Whether it"s shag, berber or plush, most carpet fiber is made from nylon, polypropylene, polyester or acrylic, and often treated with chemicals for stain resistance and glued to the floor with toxic adhesives.

Chemical releases from carpets have been blamed for "sick building syndrome," a situation in which occupants of a building experience acute health effects—such as headaches, rashes and nausea—that diminish or stop when they leave the building. One of the chemicals historically used in glues and released from the carpet"s backing material is 4-PC (4-phenylcyclohexene), which can cause such symptoms. A 2001 report from the Environmental Protection Agency (EPA) concluded, "Poor indoor air quality can reduce a person"s ability to perform specific mental tasks requiring concentration, calculation or memory."

If you are concerned about indoor air quality, there are several companies, such as Natural Home in California, that sell natural fiber carpets that don"t require toxic adhesives. The National Audubon Society building in New York City, one of the nation"s first "green" office buildings certified by the U.S. Green Building Council, uses carpeting that is 100 percent un-dyed wool. The carpet underlayer is made of jute, a plant fiber, and is tacked down, avoiding the use of toxic glue (except on the stairs). When carpet shopping, look for a green label from the Carpet and Rug Institute, which certifies products with low chemical emissions from volatile organic compounds (VOCs), organic compounds that evaporate readily into the air.

If you want more traditional wood or other hard-surface flooring, avoid materials treated with veneers that emit VOCs, or products made with particleboard, which is often held together with formaldehyde, a possible carcinogen. Other green flooring options to consider include ceramic tiles and linoleum, made with linseed oil, cork, and wood dust—all renewable resources.

CONTACTS: Natural Home, (707) 824-0914, www.naturalhomeproducts.com; U.S. Green Building Council, (202) 828-7422, www.usgbc.org; Carpet and Rug Institute, (800) 882-2246, www.carpet-rug.com