4 March 2003
Questions About Common Chemicals
and health groups are pushing to restrict the use of phthalates
- compounds used in cosmetics, toys and medical devices
David Kohn is a freelance writer.
have become ubiquitous: a group of little-known chemicals used in
everything from nail polish to skin moisturizers to toys to shower
curtains to time-release capsules to vinyl flooring. They soften
plastic and dissolve fragrance into perfume. They are the new car
smell in new cars.
are they safe? Some researchers say there is evidence that the chemicals
can cause birth defects and damage the male reproductive system.
Several environmental and health groups are pushing to restrict
the compounds' use in cosmetics, toys and medical devices.
chemicals in question are a family of versatile substances known
as phthalates, widely used for the past 50 years. U.S. manufacturers
produce around a billion pounds a year.
boots, swimming pool liners, traffic cones, insulation on electrical
wiring - anything you see that's plastic, it's likely that it contains
phthalates. They're everywhere," says Mike Shelby, director
of the Center for the Evaluation of Risks to Human Reproduction
at the National Institute of Environmental Health Services. The
Center has spent the past 18 months studying phthalate risks.
have long known that relatively large doses of some phthalates (pronounced
"tha-lates") can lead to health problems, including cancer.
But researchers have begun to suspect that lower levels may also
have negative effects. And new research suggests that humans are
being exposed to higher levels of phthalates than previously realized.
is on everybody's radar now," says Boston University environmental
epidemiologist Richard Clapp. "We may not have seen the fire
yet, but there's an awful lot of smoke."
to toxicologist Paul Foster of the National Institute of Environmental
Health Sciences, researchers are finding that smaller doses than
previously realized can cause harm. His recent work on how the chemicals
affect the development of the rat reproductive system suggests that
fetuses in the first trimester are particularly vulnerable.
lowest level that produced adverse effects in the rats was 100 milligrams
a day per kilogram of body weight. This is about 500 times more
than what a 2001 study by the national Centers for Disease Control
and Prevention found in the general human population. Many toxicologists
prefer the level to be 1,000 times higher than a level that produces
adverse effects. "When you're dealing with things that cause
birth defects," Foster says, "you like to have a nice
cushion." Foster also notes that he examined only one compound,
dibutyl phthalate (DBP). Along with one other compound, Di 2-ethylhexyl
phthalate (DEHP), DBP is considered to be the most toxic phthalate.
don't think anyone needs to panic," he says. "But I don't
feel really comfortable with young women who are being exposed to
two or three different phthalates."
groups counter that phthalate-containing products pose no danger
to humans. "Exposure in humans is well below levels that have
shown no effects in animals," says Gerald McEwen, vice president
for science at the Cosmetic, Toiletry, and Fragrance Association,
based in Washington, D.C. "The data shows that these [levels
of] chemicals are safe."
phthalate researchers say the jury is still out on phthalate risks
- particularly their threat to developing fetuses and children.
of animal studies have shown that phthalates can disrupt the endocrine
system, inhibiting male hormones and causing male infertility and
birth defects. But animal studies alone do not provide enough proof,
says Marian Stanley, manager of the American Chemistry Council's
Phthalate Esters Panel, which presents the industry's side in the
debate. "Nobody's been able to reliably link any harmful effects
to humans," she says.
reason, says Shelby of the Center for the Evaluation of Risks to
Human Reproduction, is that research on humans barely exists. "Industry
says there is no human evidence, and that's true," says Shelby.
"But the absence of evidence doesn't mean there's no effect.
In this case, it means that no one's studied it."
concern over phthalates grows, more scientists are doing research
on humans. A study published last year in Environmental Health Perspectives,
the official journal of the National Institute of Environmental
Health Sciences, found that a group of men with DNA-damaged sperm
also had higher levels of diethyl phthalate (DEP) - regarded as
one of the less toxic phthalates. "The data suggests there
may be an association between phthalates and problems with semen.
It's intriguing," says the study's leader, Professor Russ Hauser
of the Harvard School of Public Health.
regulators have already restricted some phthalate use. Earlier this
year, the Food and Drug Administration recommended that when performing
procedures on male babies and boys, as well as women pregnant with
boys, hospitals avoid using IV bags, blood bags and tubing made
with DEHP. The compound, which makes the devices pliable, can leach
from the plastic. The FDA also asked, but didn't require, manufacturers
to label DEHP-containing medical devices so hospitals could more
easily avoid them.
of the recent debate has focused on the chemicals' presence in cosmetics.
A 2001 study by the CDC found widespread phthalate exposure, including
higher than average levels of some phthalates in the urine of women
of childbearing age. Some women exceeded the EPA's safety standard,
a finding that scientists say are enough of a concern to warrant
further study. A follow-up CDC study in January reported similar
phthalates found in largest quantities were DBP and DEP , which
tend to be used in cosmetics and perfumes. The EPA's "reference
dose" - an estimate of the maximum daily exposure that is unlikely
to cause adverse health effects - for DEP and DBP is 0.1 milligram
per kilogram of body weight per day (a kilogram is 2.2 pounds).
The agency, which set those levels over a decade ago, says it is
now revising them.
surmised that the elevated levels of DBP and DEP could be caused
by women's use of beauty care products.
cause for concern," says researcher John Brock, who oversaw
the CDC study. "We have broad exposure to phthalates in the
population. We have animal studies that show risk. So we really
need to know where these exposures are coming from."
response to the finding of elevated levels in women of childbearing
age, a coalition of three environmental groups decided last year
to analyze phthalate levels in cosmetics. They tested 72 name-brand
cosmetics - everything from shampoo to perfume to deodorant - and
found phthalates in 52.
never found the word 'phthalate.' We read thousands of labels,"
says Charlotte Brody, director of Health Care Without Harm in Washington,
D.C., one of the groups. Federal labeling laws do not require phthalates
to appear on ingredient lists of many cosmetics and other products;
they are usually part of the "fragrance," which is considered
a trade secret, and so may be omitted from labels.
of women are being exposed to multiple phthalates," says Jane
Houlihan, director of research at the Environmental Working Group,
another coalition partner. "And they have no way of even knowing
what products contain phthalates."
Lynn Goldman, for one, would like to know. Her 6-year-old daughter
loves nail polish, and also bites her nails.
have no idea what is in those products," says Goldman, a professor
of environmental health at Johns Hopkins University and former Environmental
Protection Agency official who was in charge of regulating toxic
chemicals during the Clinton administration.
and nail salon workers "are breathing nail lacquers and hair
sprays day in and day out," she said.
the FDA says phthalate-containing beauty products are safe. In November,
the Cosmetics Ingredient Review panel (CIR), an industry-funded
safety panel that advises the FDA, reviewed existing scientific
data and found that phthalates in cosmetics pose no risk. The FDA
consensus between the CIR and the FDA was that phthalates are safe
in cosmetics," said FDA spokeswoman Veronica Castro.
cosmetics companies, including Aveda, have stopped using phthalates
in new products. Recently, the European Union decided to phase out
DEHP and DBP from use in cosmetics. The chemical industry argues
that the move was not based on science, but on irrational fear and
that some cosmetics are made without phthalates, Brody wonders why
manufacturers don't simply replace the controversial compounds with
other chemicals. McEwen says the answer comes down to logic: "Why
should we change from something that is absolutely safe? That doesn't
opponents say that even without ironclad proof that low levels cause
harm in humans, there is enough data to warrant a ban. Animal studies
must be considered, they say, particularly given the difficulty
of doing phthalate studies in humans.
very hard to study in people, and very hard to find problems even
when they exist," says Goldman. "If a kid grows up and
has fertility problems, are you going to know how much nail polish
his mother used during pregnancy? We need to use the animal data."
debate extends beyond cosmetics. Many soft plastic toys are made
with diisononyl phthalate (DINP), which studies show causes liver
damage in animals. Some environmental groups say the chemical, which
makes up as much of 40 percent of some plastic playthings, can leach
out at risky levels, particularly when kids suck on toys. Responding
to a combination of research and pressure, some countries have restricted
phthalates in toys. The EU has banned DINP in toys for kids 3 and
under, while Japan has announced a plan to get rid of DEHP and DINP
in toys for kids 6 and under. In 1998, U.S. toy manufacturers voluntarily
agreed to stop using phthalates in pacifiers and rattlers. But environmental
groups say many other toys still contain DINP.
the U.S. Consumer Product Safety Commission completed a four-year
study, concluding that toys with DINP were not a health risk. While
agreeing that DINP could be toxic, the commission said children
sucked on toys an average of 1.9 minutes per day, and would have
to suck for 39 minutes to ingest risky levels.
environmental and consumer groups criticize the ruling. "The
CPSC is erring on the side of exposing kids to a toxic chemical,"
said Andy Igrejas of the nonprofit, nonpartisan National Environmental
Trust, which wants DINP banned from all 5-and-under playthings.
some, the disputes over specific types of products miss the point.
"It's wrong that we're asking about phthalates just in cosmetics
or toys. People are getting phthalates from multiple sources,"
says Dr. Ted Schettler, science director for the Science and Environmental
researchers believe that phthalates can migrate from packaging into
food, especially fatty items like cheese and meat. An ongoing study
by the Silent Spring Institute is looking at air and house dust
in 120 Massachusetts houses and has found "significant concentrations"
of phthalates, including DEHP and DBP. The study has been submitted
for publication in a leading journal.
suggests we should consider inhalation as a pathway," says
toxicologist Ruthann Rudel, who led the study.
senior government researcher, who requested anonymity, said that
because phthalates are part of so many products, no one has a clear
picture of how and where humans are being exposed. He notes that
the CDC study looked for only seven compounds; there are, he says,
dozens used in commercial products.