EarthTalk: Everyday products can harm health

Is there any proof linking human breast cancer to exposure to chemicals in the environment? Or do researchers think most cases of breast cancers are genetically inherited?

A groundbreaking research study coordinated by the non-profit Silent Spring Institute and recently published by the American Cancer Society found that synthetic chemicals have likely played a large role in the rising incidence of breast cancer throughout the world over the last half-century. The study identified 216 man-made chemicals--including those found in everyday products like pesticides, cosmetics, dyes, drugs and gasoline (and diesel exhaust)--that have been shown to cause breast cancer in animals. Researchers believe these substances, many of which "mimic" naturally occurring hormones once inside the body, are also to blame for the increasing prevalence of human breast cancer.

According to epidemiologist Devra Lee Davis of the University of Pittsburgh's Graduate School of Public Health and one of the lead researchers on the new study, the more hormones cycling through a woman's body during her lifetime, the more likely she is to develop breast cancer. Synthetic chemicals that mimic hormones magnify the risk, as the body doesn't know the difference between its own real hormones and other introduced chemicals. Only one in 10 women who develop breast cancer inherits a defective gene from their parents, Davis adds, meaning that in 90 percent of breast cancer cases studied, external non-genetic agents (e.g. synthetic chemicals) contributed to the development of the cancer.

Another telling clue is the fact that the breast cancer risk of adopted children parallels the risk of the family they grew up in, not that of their biological family, as proven by analyzing medical records from Scandinavian countries that keep detailed registries following people from birth to death. "What we understand is that if cancer runs in your family it could be because your family had similar eating patterns, similar lifestyle patterns as well as lived in the same area," says Davis. "It's really important that we take another look at...the kinds of chemicals that we are using everyday," she adds. "We think that there are alternatives that can be used."

The U.S. government has been reluctant to institute new restrictions on the production of highly profitable synthetic chemicals, but European regulators are taking the issue very seriously. The European Commission's new Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) Program calls on chemical manufacturers selling anywhere in Europe to re-register and re-evaluate the potential health hazards--including cancer risks--of their products. Environmental and public health advocates hope that American chemical companies will follow that lead with chemicals sold here.

In the meantime, consumers can help prevent cancer by buying and eating organic foods, avoiding pesticides and other synthetic chemicals whenever possible, using non-plastic containers to reheat and store foods (some plastics are thought to leach cancer-causing chemicals into food when heated), and supporting government regulation and more research on synthetic chemicals and their effects.

CONTACTS: Silent Spring Institute, www.silentspring.org; European Commission's REACH Program, ec.europa.eu/environment/chemicals/reach/reach_intro.htm.

Are mothballs safe to use? If not, are there any environmentally friendly alternatives?

Even though they are not as popular as they once were, mothballs are still used by many people to keep stored clothes, furniture and carpets free of hungry pests like moths. But the very ingredients that make mothballs so effective as household pesticides--namely naphthalene or paradichlorobenzene (PDB)--also make them dangerous to any person or animal who breathes the fumes or ingests them directly. Such chemicals are often listed as primary offenders when household air is tested for indoor air pollution.

Exposure to naphthalene or PDB can induce relatively minor human health problems such as nausea, vomiting, headache, coughing, burning eyes and shortness of breath. The World Health Organization's International Agency for Research on Cancer considers both naphthalene and PDB to be hazardous carcinogens as well. These chemicals, which are also found in some dry cleaning agents as well as household air fresheners and solid toilet-bowl deodorizers, have been found to nearly double the risk of non-Hodgkin's lymphoma--a cancer of the blood--for those who come into frequent contact with them.

So what's a conscientious homemaker to do? For starters, removing all mothballs and their flakes from the home is a good first step. Experts suggest donning gloves and even perhaps a mask before manually removing intact mothballs. Affected clothing can be machine-washed and dried several times, preferably on high heat settings. If the smell of mothballs continues to linger, any such clothes can be ironed--also with high heat settings, which tend to break down the active chemicals quicker. Sunlight also breaks down naphthalene and PDB, so leaving any affected items outside on hot sunny days may also help.

Carpets and upholstery co-mingled with mothballs should be vacuumed thoroughly, with vacuum cleaner bags containing mothball traces emptied immediately outdoors. If the mothball smell lingers after vacuuming, a professional cleaning might do the trick, although such services can introduce other harmful chemicals, such as the carcinogen perchloroethylene, into the household as well. (ChemDry and Zoots both offer in-home carpet and upholstery cleaning services that do not rely on harmful chemicals.) After any kind of mothball removal effort, the cleaned house or closet should be aired out, ideally with one or more fans blowing as much fresh outdoor air through as possible.

As to alternatives for keeping moths and other critters away from clothes and other valuable fabrics, Care2.com's green home guru and author Annie Berthold-Bond suggests using home-made sachet pillows filled with a dried herb mixture combining two parts each of rosemary and mint, one part each of thyme and ginseng, and eight parts whole cloves. The herbs can be mixed and combined in the center of a bandana or handkerchief that is then tied with a ribbon and placed among the stored items. Also, Richards Housewares makes Moth-Away Herbal Moth Repellant, a pre-packaged product that makes use of a similar formula. It's available from planetnatural.com and other online environmental product websites.

CONTACTS: U.S. Environmental Protection Agency (EPA) Napthalene page, www.epa.gov/ttn/atw/hlthef/naphthal.html; PlanetNatural Moth-Away page, www.planetnatural.com/site/moth-away.html.