Many common household products contain compounds that could be affecting our health
Newsweek, Anne Underwood
Published January 28, 2008
As an Alaskan fisherman, Timothy June, 54, used to think that he was safe
from industrial pollutants at his home in Haines—a town with a population
of 2,400 people and 4,000 eagles, with 20 million acres of protected
wilderness nearby. But in early 2007, June agreed to take part in a survey
of 35 Americans from seven states. It was a biomonitoring project, in
which people's blood and urine were tested for traces of chemicals—in this
case, three potentially hazardous classes of compounds found in common
household products like shampoo, tin cans, shower curtains and upholstery.
The results—released in November in a report called "Is It in Us?" by a
coalition of environmental groups—were not reassuring. Every one of the
participants, ranging from an Illinois state legislator to a Massachusetts
minister, tested positive for all three classes of contaminants. And while
the simple presence of these chemicals doesn't necessarily indicate a
health risk, the fact that typical Americans carry these chemicals at all
shocked June and his fellow participants. As Stephanie Felten, 28, of
Aurora, Ill., put it, "Why should chemical companies be allowed to roll
the dice on my health?"
Clearly, there are chemicals in our bodies that don't belong there. The
Centers for Disease Control and Prevention conducts a large, ongoing
survey that has found 148 chemicals in Americans of all ages, including
lead, mercury, dioxins and PCBs. Other scientists have detected
antibacterial agents from liquid soaps in breast milk, infants' cord blood
and the urine of young girls. And in 2005, the Environmental Working Group
found an average of 200 chemicals in the cord blood of 10 newborns,
including known carcinogens and neurotoxins. "Our babies are being born
pre-polluted," says Sharyle Patton of Commonweal, which cosponsored "Is It
in Us?" "This is going to be the next big environmental issue after
climate change."
The shocking thing to most Americans is that we really don't know the
health effects of many chemicals on the market today. Under the Toxic
Substances Control Act of 1976, chemicals already in use were
grandfathered in without scrutiny. These include the three classes of
compounds targeted in "Is It in Us?"—a plastic strengthener called
bisphenol A (BPA), brominated flame retardants known as PBDEs and plastic
softeners called phthalates. The chemical industry says these compounds
have been used safely for decades, and certainly they do not have the
overtly toxic properties of mercury or lead. But in animal studies and
human cell cultures, they mimic hormones, with effects even at minute
levels, down to parts per billion. Scientists say we're now awash in a
chemical brew of hormone-mimicking compounds that didn't exist 100 years
ago. "We've changed the nature of nature," says Devra Lee Davis, director
of the Center for Environmental Oncology at the University of Pittsburgh.
Take bisphenol A. It's a basic constituent of the polycarbonate plastics
found in many baby bottles, sippy cups and juice bottles. A highly
versatile compound, it is also found in dental sealants, CDs, DVDs and the
resin linings of food and beverage containers, including many cans and
takeout cartons. But most scientists say small amounts can leach out—and
ultimately find their way into our bodies—when the plastics start to break
down under high heat or wear and tear. The CDC has found BPA in 92 percent
of Americans age 6 and older who were tested. But the chemical industry
says it's safe—and the Food and Drug Administration agrees. "It's not
possible to contact harmful levels of it," says Steven Hentges of the
American Chemistry Council, which represents the major chemical companies.
Reproductive biologists aren't so sure. Patricia Hunt of Washington State
University was alerted to possible dangers of BPA in 1999 when her mouse
study on an unrelated topic suddenly went haywire, with dozens of female
mice unexpectedly developing chromosomal abnormalities in the eggs they
carried in their ovaries. As it turned out, a lab worker had used the
wrong detergent to clean the animals' cages—one that caused BPA to leach
out of the plastic cages and feeding bottles. Hunt tried washing brand-new
cages with the same detergent to confirm the source of the problem. She
then began studying BPA exposures in unborn rodents, which she followed
into adulthood. The results were striking. Almost half the eggs of female
mice exposed to low doses of BPA during gestation carried extra copies of
chromosomes or were missing chromosomes. No one has replicated the
findings.
There are other potential effects. Hundreds of animal and test-tube
studies suggest that low-dose exposures, particularly during gestation,
may later lead to breast and prostate cancer, abnormalities in the
reproductive tract and behavioral problems, among other things. But there
is disagreement about the implications for human health. Two groups
convened by the National Institutes of Health have reached opposite
conclusions. In 2007, advisers to the government's National Toxicology
Program found "minimal" cause for concern. Meanwhile, another scientific
panel produced a consensus statement saying that, based on animal data,
common levels of exposure could pose a problem and that further study was
needed. "We can't say there are conclusive data in humans," says Frederick
vom Saal of the University of Missouri, who headed the second panel. "But
given the fact that we're seeing irreparable damage in animals, for
heaven's sake, let's get this out of products our babies are coming in
contact with."
No government in the world has seen the need to do that yet. But two weeks
ago, Michigan Rep. John Dingell, chair of the House Committee on Energy
and Commerce, sent letters to seven manufacturers of infant formula asking
if their cans were lined with BPA and if they had tested their products
for it. In 2006 Whole Foods stopped carrying baby bottles made from
polycarbonate plastic, which contains BPA. The chain now sells only
BPA-free bottles and sippy cups.
Phthalates have also raised concern. The compounds are used to soften the
plastics in products ranging from rubber duckies and vinyl shower curtains
to certain medical tubing and IV bags. They are also found in hundreds of
personal-care products, including many fragrances, body lotions, nail
polishes and shampoos. Again, 30 years of data from institutions like the
NIH and EPA point to potential problems in animals stemming from prenatal
exposure, including abnormalities in the reproductive tract and a decline
of sperm quality. Now there is a smattering of human studies, too. In 2006
Danish researchers found that higher levels of a particular phthalate in
mothers' breast milk correlated with lower testosterone in male babies at
1 to 3 months of age. Similarly, Dr. Russ Hauser at Harvard studied
roughly 500 men at a fertility clinic and found that those with higher
levels of certain phthalates in their urine had lower sperm counts and
sperm motility. A Swedish study of young military recruits, however, found
no such correlation. These are all association studies—which by definition
cannot prove cause and effect.
Other scientists are starting to look at what happens when these chemicals
are combined. L. Earl Gray Jr., a research biologist at the EPA, has
tested mixtures of two or more phthalates in animals. He deliberately
selected doses of each that were too low to cause effects individually—yet
found that as many as 50 percent of male rats who were exposed to the
combination in utero developed abnormalities in the reproductive tract. In
his latest study, he combined three phthalates with four pesticides and
found that at the highest doses, the effects equaled those of a sevenfold
dose of a single phthalate. "All the males were malformed," he says.
The toy industry contends that phthalates pose no danger, particularly a
widely used one called DINP. This chemical "has been well studied here in
the U.S. and in Europe and found to be safe specifically for kids'
products," says Joan Lawrence, a vice president of the Toy Industry
Association. She notes that companies cannot easily replace it because
none of the potential substitutes "has its lengthy safety record."
Nonetheless, last October, California Gov. Arnold Schwarzenegger signed a
ban on the use of six phthalates in children's products sold in the
state—though three of them, including DINP, are prohibited only in items
that kids under 3 are likely to put in their mouths. In December, Toys "R"
Us notified its vendors of its intention to comply with the California ban
by Jan. 1, 2009, the date the law takes effect. Mattel is already in
compliance.
Finally there are the flame retardants, PBDEs. They turn up in fabrics,
upholstery, foam mattresses, circuit boards and the casings of computers
and televisions—and apparently escape into indoor air and dust. Animal
studies show they can have negative impacts on learning and memory, sperm
counts and thyroid functioning in rats and mice. PBDEs tend to linger a
long time in the body, and one mixture in particular seems "quite
biologically active, especially during development, as we've seen in
studies on rats, mice and fish," says Linda Birnbaum, director of
experimental toxicology at the EPA. "If I were nursing my baby, I wouldn't
stop because of PBDEs in breast milk, but many of us wish they weren't
there." According to the EPA, 11 states—including California, Maine,
Michigan and New York—have bans on two major types.
It could take decades to resolve doubts about the safety of all these
chemicals, one way or the other. But Timothy June isn't waiting. He's
stopped buying tomato sauce in tin cans to avoid the BPA, which scientists
say tends to leach out of can linings when the contents are particularly
acidic. He's ditched his vinyl shower curtain in favor of a cloth one. And
he's considering getting rid of the foam mattress on his fishing boat. "I
guess the survey had a bigger impact on me than I realized," he says.
Let's all hope the chemicals aren't having an even bigger impact on us.
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