Hygiene leaves kids with
loads of triclosan
Levels
of a controversial chemical meant to kill bacteria spike in the bodies of young
children after they brush their teeth or wash their hands, according to a new
study.
U.S.
manufacturers are phasing triclosan out of hand soaps after the Food and Drug
Administration banned it effective last year amid concerns that the compound disrupted
the body's hormone systems.
It
remains in Colgate Total toothpaste, some cleaning products and cosmetics.
Health experts say exposure is best avoided for babies in the womb and
developing children.
The
latest study, published in the
journal Environmental Science & Technology, is one of the first
to show that children’s levels rise through their first few years of life. Hand
washing and teeth brushing have speedy, significant impact on levels, the
researchers found.
“There’s very little data on the exposure in those first years of life,” said the senior author of the study, Joe Braun, an assistant professor and researcher at Brown University. “There are a lot of behavioral changes in the those years, and environmental chemicals can play a role.”
Braun
and colleagues tested the urine of 389 mothers and their children from
Cincinnati, collecting samples from the women three times during pregnancy and
from the children periodically between 1 and 8 years old.
They
found triclosan in more than 70 percent of the samples. Among 8 year olds,
levels were 66 percent higher in those that used hand soap. And more washing
left the children with higher loads—those who reported washing their hands more
than five times per day had more than four times the triclosan concentrations
than those washing once or less per day.
Children
who had brushed their teeth within the last day had levels 2.5 times higher
than those who had a toothpaste-free 24-hour span.
“It’s
a thorough, well-done analysis,” said Isaac Pessah, a researcher and professor
at University of California, Davis, who was not involved in the study. “Given
the high concentrations [of triclosan] in personal care products, you’re seeing
that the concentrations in the end user are also quite high.”
Braun
said the levels of triclosan rose as the children aged, eventually leveling
off. “Their levels were almost to moms’ levels by the time they reached 5 to 8
years of age.”
This,
he said, is likely due to more frequent use of personal care products as the
kids aged. Despite the hand soap ban, triclosan remains on the market because
it is effective at fighting plaque and gingivitis.
Colgate
uses 0.3 percent of the antibacterial to “fight harmful plaque germs.”
Colgate’s
parent company, Colgate-Palmolive, did not respond to requests to comment on
Braun’s study. The company has, however, maintained triclosan’s safety in its
toothpaste and its role in fighting plaque and gum disease.
“As
for claims of endocrine disruption, the World Health Organization defines an
endocrine disruptor as something harmful to one’s health, and that is simply
not the case here,” wrote Colgate’s head of R&D, Patricia Verduin, in
response to media reports on triclosan’s endocrine impacts.
Braun,
however, said there is “quite compelling” evidence from animal studies that
triclosan decreases thyroid hormone levels. Properly functioning thyroid
hormones are critical for brain development.
Just
last month, using the same mothers and children, Braun and others reported that
mothers’ triclosan exposure during pregnancy was linked to lower birth weights,
smaller heads and earlier births.
In
addition, Pessah and
colleagues reported triclosan hinders proper muscle
development. The researchers used mice and fish, finding that triclosan affects
the process responsible for muscle contraction.
Braun
said the study was limited in that they didn’t know what brands of toothpaste
or soap kids were using. Also, product use was self-reported and mothers may
not want to say their kids weren’t brushing their teeth, he said.
Researchers
do not argue triclosan’s effectiveness at reducing bacteria. And Pessah said
there is a role in protecting oral health.
“Perhaps
if we would have made triclosan available by prescription for some people, like
those with secondary infection on their gums from diabetes, we wouldn’t reach
the contamination levels we now see.”
Braun
said people might take pause next time they’re browsing for bathroom and
cleaning products.
“There
is evidence that triclosan is positive for dental health, but if it’s not
recommended from your dentist that you use this product, then don’t,” Braun
said. “Especially if you’re a young child or pregnant woman.”