The chemical triclosan has been linked to cancer-cell growth and disrupted development
in animals. Regulators are reviewing whether it’s safe to put in soap,
cutting boards and toys. Consumer companies are phasing it out.
Minnesota voted in May to ban it in many products.
At the same
time, millions of Americans are putting it in their mouths every day, by
way of a top-selling toothpaste that uses the antibacterial chemical to
head off gum disease -- Colgate-Palmolive Co.’s Total.
Total
is safe, Colgate says, citing the rigorous Food and Drug Administration
process that led to the toothpaste’s 1997 approval as an
over-the-counter drug. A closer look at that application process,
however, reveals that some of the scientific findings Colgate put
forward to establish triclosan’s safety in toothpaste weren’t black and
white -- and weren’t, until this year, available to the public.
Colgate’s
Total application included 35 pages summarizing toxicology studies on
triclosan, which the FDA withheld from view. The agency released the
pages earlier this year in response to a lawsuit over a Freedom of
Information Act request. Later, following inquiries from Bloomberg News,
the FDA put the pages on its website.
The
pages show how even with one of the U.S.’s most stringent regulatory
processes -- FDA approval of a new drug -- the government relies on
company-backed science to show products are safe and effective. The
recently released pages, taken alongside new research on triclosan,
raise questions about whether the agency did appropriate due diligence
in approving Total 17 years ago, and whether its approval should stand
in light of new research, said three scientists who reviewed the pages
at Bloomberg News’s request.
Rodent Bones
Among the pages were studies showing fetal bone malformations in mice and rats. Colgate
said the findings weren’t relevant. Viewed through the prism of today’s
science, such malformations look more like a signal that triclosan is
disrupting the endocrine system and throwing off hormonal functioning,
according to the three scientists.
Colgate’s application
materials also show that the FDA asked questions about the thoroughness
of cancer studies, which are partly addressed in recently released
documents.
Some questions about triclosan’s potential impact on
people are, by nature, unanswerable. Humans are exposed to dozens of
chemicals that may interact in the body, making it almost impossible to
link one substance to one disease, said Thomas Zoeller, a biology
professor at the University of Massachusetts Amherst, who specializes in
how chemicals affect the endocrine system.
‘Huge Risk’
“We
have created a system where we are testing these chemicals out on the
human population. I love the idea they are all safe,” Zoeller said. “But
when we have studies on animals that suggest otherwise, I think we’re
taking a huge risk.”
New York-based Colgate
isn’t accused of wrongdoing, and the 35 pages don’t prove triclosan is
harmful. It was the FDA’s decision to keep the documents off of its
website, Colgate said.
The FDA followed standard procedure by
redacting information that had come from a third party, said spokeswoman
Andrea Fischer. Some studies were done in the labs of Ciba-Geigy, the
first triclosan maker and a predecessor to its current primary maker, BASF SE,
according to the documents. The pages didn’t denote which studies were
done by an outside party, or who the party was. Fischer declined to
identify them.
Fights Gingivitis
Colgate said Total’s
effectiveness and safety are supported by more than 80 clinical studies
involving 19,000 people, and that it gave the FDA 98 volumes, numbering
hundreds of pages each, in support of Total. Colgate submits annual
reports to the FDA reviewing new science and safety findings, said
Colgate spokesman Thomas DiPiazza.
“In
the nearly 18 years that Colgate Total has been on the market in the
U.S., there has been no signal of a safety issue from adverse-event
reports,” DiPiazza said. Colgate also pointed to an independent 2013
review by the Cochrane Oral Health Group, a network of doctors,
researchers and health advocates, which found no evidence of harmful
effects associated with using Colgate Total.
Total has an
important health benefit because it fights plaque and gingivitis,
DiPiazza said. Gingivitis can progress to periodontal disease, which affects almost half of Americans 30 and over, according to a 2012 study by the Centers for Disease Control and Prevention.
Soap Review
The
FDA reviews all new safety information on ingredients to determine
whether a reassessment is necessary, said Jeff Ventura, a spokesman. The
agency is revisiting triclosan in hand soaps though not in Total, said Sandra Kweder,
deputy director of the agency’s Office of New Drugs. That’s because
while triclosan hasn’t been proven superior to soap and water at washing
hands, she said, its benefit as an active ingredient in toothpaste was
made clear through its FDA approval process.
Colgate removed
triclosan from its Softsoap liquid handsoaps and Palmolive antibacterial
dish liquid in 2011, citing changing consumer preferences and superior
formulations. It said it has no plans to reformulate Total, which is the
only triclosan toothpaste approved for U.S. sale.
This article
is based on interviews with Colgate, former and current FDA staff and
oral biology experts, transcripts of FDA meetings, as well as on the 35
pages, which the FDA shared in January with the Natural Resources
Defense Council, a public-health advocate that sued for them. The
scientists who examined the pages included Zoeller, a second
university-affiliated endocrine specialist, and an environmental
toxicologist affiliated with the Environmental Working Group, a public
health advocacy.
Pet-Food Dispensers
Of the more than
84,000 chemicals sold in the U.S., few are attracting more scrutiny than
triclosan. Used for decades in handsoaps, it is now part of almost 200
products including rugs and pet-food dispensers. Companies including Johnson & Johnson and Procter & Gamble Co. have vowed to remove it from their lineups. In May, Avon Products Inc. announced its plans to go triclosan-free.
Those
moves are coming in part as consumers, armed with toxicity ranking
systems such as the Environmental Working Group’s Skin Deep Database,
have turned away from chemicals including Bisphenol A and phthalates,
even in the absence of firm scientific or regulatory conclusions.
Wariness
is mounting as factors from environment to diet are blamed for a global
rise in endocrine-related diseases. Breast, ovarian, prostate and
testicular cancer rates have increased over the past 40 to 50 years,
according to a 2012 report from the World Health Organization and the United Nations Environment Programme.
A rise in preterm and low birthweight babies, early breast development
in girls and undescended testicles in boys may be linked to
endocrine-disrupting chemicals, the report says.
Regular Exposure
Zoeller,
the endocrine specialist, said that while an estimated 800 to 1,000
chemicals are believed to disrupt the endocrine system, triclosan is one
of about 10 to which people are regularly exposed. “We may not have to
change very much to have a big impact,” he said.
Total, the No. 3
selling brand in the U.S., lost 2 percent of its market share last
year, with $189.8 million in sales for the year that ended on Jan. 26,
according to market research firm Mintel Group Ltd. Colgate’s Tom’s of
Maine line grew 14 percent, to $38.9 million, suggesting shoppers are
gravitating toward more natural options, the report said.
Procter & Gamble,
which makes Crest 3D White and Crest Pro-Health -- the top two U.S.
toothpastes according to Mintel -- has sought to capitalize. A Google
search for “triclosan” and “toothpaste” brings up an advertisement
linked to a Procter & Gamble site touting Crest products as “100% triclosan free.”
Triclosan-Free
P&G’s
oral-care products have been triclosan-free in the U.S. and several
other markets “for a number of years,” said Kristopher Parlett, a
spokesman for the Cincinnati-based company. P&G doesn’t produce or
market triclosan-containing oral care products anywhere, he added.
GlaxoSmithKline Plc,
which once had triclosan in some Aquafresh and Sensodyne toothpastes,
has reformulated all of its oral care products that previously contained
it, said spokeswoman Joanmarie Goddard. She couldn’t say what year they
had been reformulated or whether triclosan versions had been sold in
the U.S. The decision was a response to consumer concern that triclosan
across a range of products “may have a negative environmental impact in
the future,” she said.
Hand Scrubs
From its beginnings
as an ingredient in surgical hand scrubs, triclosan -- also identified
as 5-Chloro-2-(2,4-dichlorophenoxy)phenol -- has grown to a $100 million
a year chemical globally, according to statistics from the Kline Group.
BASF, based in Ludwigshafen, Germany, sells it under the trade names
Irgasan and Irgacare. India-based Kumar Organic Products Ltd. and Vivimed Labs Ltd. also make it.
BASF
says that 40 years of global studies and publications prove triclosan’s
efficacy in oral care and cosmetic products, as well as in hand
disinfectants and other health-care applications, according to Thomas Nonnast,
a spokesman. Klaus Nussbaum, a spokesman for Kumar, said studies have
established triclosan’s safety. Vivimed didn’t respond to requests for
comment.
While company-sponsored safety tests on triclosan that
would become part of Colgate’s FDA application for Total began as early
as 1968, U.S. agencies have yet to comprehensively review it for other
uses.
Safety Tests
In 1974, the FDA proposed issuing a
so-called monograph that would determine whether antibacterial
ingredients such as triclosan were considered safe and effective for
hand soaps. Two years later, the U.S. Toxic Substances Control Act of
1976, which aimed to comprehensively regulate chemicals, grandfathered
in existing substances with no safety testing.
The law gave the
EPA -- which oversees triclosan’s use in durable goods including fabrics
and sealants -- the power to restrict or test substances. It excluded
food, drugs and cosmetics, which fall under the FDA’s mandate. The FDA,
four decades after its first promise, has yet to issue a ruling on
whether triclosan is safe or effective in soaps.
In the meantime, triclosan made its way into toothpaste.
Colgate
spent 10 years and $38 million developing Colgate Total, according to
Mintel. Introduced in 1992, it was marketed in almost 100 countries
before gaining U.S. approval, according to transcripts of FDA meetings.
Four Applications
Colgate
applied to the U.S. four times starting in 1992, according to FDA
records, before gaining the FDA’s blessing on July 11, 1997. In a
statement at the time, Colgate called Total “the most significant
advancement in home dental care since the introduction of fluoride.”
In
the early 2000’s, Caren Helbing, a professor at the University of
Victoria in Canada, noticed the SARS outbreak in China had led to a
germ-killing frenzy. Seeing triclosan listed as an active ingredient in
many antibacterial products, she looked up its chemical structure. It
was similar to both thyroid hormones and to polychlorinated biphenyls,
or PCBs, she said. Such a structure, she and other scientists have said,
allow the chemicals to become active on hormone receptors.
Helbing,
who has a Ph.D. in biochemistry and microbiology, found that tadpoles
exposed to triclosan developed into smaller froglets and had malformed
legs -- results that she and other scientists published in the peer-reviewed Aquatic Toxicology journal in 2006.
Thyroid Function
Other studies found no such links between the chemical and hormone function. A 2011 paper
published in Science of the Total Environment found that over four
years, the use of triclosan toothpaste had no detectable effect on
thyroid function in humans. Three of that study’s five authors received a
grant from Colgate. One, Greg Seymour, a professor at the School of
Medicine at the University of Queensland, said Colgate requested the
analysis of thyroid hormones after it granted them money for a separate
study on gingivitis. Colgate had no input on data collection or
analysis, he said.
The Cochrane paper,
which Colgate cited in its favor, comes to a more complex conclusion.
The review of more than 30 studies published from 1990 to 2012 found
“moderate quality evidence” that Total is more effective than other
toothpastes at fighting gum bleeding and inflammation. On the topic of
safety, authors Philip Riley and Thomas Lamont, speaking about the
review in a podcast, said the studies didn’t cover enough years to allow them to investigate any long-term ill effects.
Long-Term Exposure
“What
I would be concerned about is the amount people are exposed to over
time,” said William Bowen, a professor emeritus at the University of
Rochester Medical Center, who specializes in oral biology and also
served on a subcommittee at the FDA that evaluated dental products in
the 1990s.
Meanwhile, triclosan is showing up in humans and the environment. It was found
in the urine of 75 percent of 2,517 Americans tested, including
children, according to a 2003 study by the Centers for Disease Control
and Prevention. It and a related chemical, triclocarban, were detected
in 90 percent of surface water samples from the Great Lakes and in many
fish species, according to a July 2014 study by the Canadian
Environmental Law Association.
Scientific studies that have raised health concerns include one 2012 study linking triclosan to reduced fertility in mice, and another
that year suggesting it could impair muscle function. A study last year
linked it to lowered sperm production and changed sperm shape in rats.
Triclosan’s core credentials have also come under scrutiny: While some
studies have supported its benefit in killing bacteria, others have
found it no more effective than soap and water -- and in some cases suggested it could support growth of bacteria including the type that causes staph infections.
EU Ban
In
2010, the European Union banned triclosan in materials that come into
contact with food. Three years later, the EPA, which reviewed the
chemical in 2008, began
another review, 10 years earlier than planned. It cited the “rapidly
developing scientific database” on the chemical, which includes studies
on thyroid effects, according to its website.
Amid these
debates, the Natural Resources Defense Council turned its attention to
one of triclosan’s main regulators. In 2013, it sued the FDA for the
toxicology data the agency had relied on in approving Colgate Total. In
January, the FDA handed the NRDC the 35 pages and later put them online
along with a previously unreleased cancer study and other information.
The
pages included a summary of a 1992 study showing that pregnant mice
receiving higher doses of triclosan had lower-weight fetuses and
increased incidence of irregular bone formation in their skulls and paw
bones. Five of the 120 mice delivered prematurely. A study on pregnant
rats the same year found that at higher doses, rat litters had increased
incidence of delayed bone formation in areas including the skull,
vertebrae and pelvis.
The application dismissed both results --
saying the premature births weren’t dose related and were therefore
“incidental.” The bone-formation issues were due to toxic effects on the
mother, not the fetus, the summary said.
Not Enough Detail
The summaries didn’t provide enough detail to justify those dismissals, according to the scientists reviewing them.
“Wow.
They kept that private?” said Zoeller of the University of
Massachusetts. “The distinction between maternal and fetal toxicity is
an excuse to do nothing. And it’s not scientifically justifiable.”
Such
results could have served as clues for later scientists if they had
been made public, said the third reviewer, Johanna Congleton, a
scientist at the EWG who has a PhD in Environmental Toxicology from
Cornell University.
Amplified Effect
Since Total’s
approval, researchers have gained new insights into chemicals that
disrupt the endocrine system. The Total studies focused on whether
triclosan had an amplified effect as exposure levels rose -- a model
consistent with a longstanding belief that the bigger the dose, the
greater the poison.
Newer science has shown that even small
doses of certain chemicals can significantly affect hormone functions,
if they are delivered at the wrong moment -- and that rising doses may
cause new unpredictable effects, rather than a rising incidence of the
same issue. Some of the data Colgate
dismissed in the non-public pages are “almost a hallmark of endocrine
disruption,” said Helbing, who conducted the study on frogs.
The
effects Helbing had documented -- smaller froglets and malformed legs
-- could be seen with doses equivalent to 1/10 of what a person would
use in squeezing a pea-sized amount of Total onto a toothbrush twice a
day, Helbing said.
The 35 pages of recently released documents
also include a cancer study in which triclosan was fed to rats for as
long as two years. FDA reviewers deemed the study inadequate, according
to the recently released document, and called for another.
Industry Alliance
Shortly
after, in February 1996, an FDA dental-products panel said the agency
was working closely on a new cancer study with the Triclosan Industry
Alliance -- a trade group whose members, according to documents on the
FDA’s website, included Colgate, Procter & Gamble and Ciba Specialty Chemicals. Colgate said it believes the alliance no longer exists.
According
to the minutes of the meeting obtained through a Freedom of Information
Act request, the study was expected in 18 months. Total was approved 17
months later.
An industry group’s study was submitted to the
FDA in 1999, said Colgate’s DiPiazza. Both Colgate and the FDA declined
to make that study available.
Carcinogenicity Concerns
The
FDA, in response to a Bloomberg News inquiry, said the agency’s
concerns about carcinogenicity had been resolved by a cancer study that
was submitted in January 1997. The study, which the FDA put on its
website following a Bloomberg News inquiry, “supports the FDA’s
conclusion that triclosan does not pose a cancer risk for humans,”
DiPiazza said.
David Kessler, a former commissioner of the FDA
from 1990 to 1997, just prior to when Colgate Total was approved, said
he couldn’t comment on the thoroughness of the agency’s review.
Typically, he said, only confidential commercial information is redacted
from public documents. It’s the manufacturer’s responsibility, he said,
to assure its product is safe and that relevant information is made
public.
“The real question is did Colgate do a good job,” Kessler said.
Colgate
continues to reference its FDA bona fides. This spring, Minnesota
became the first state to pass a triclosan ban. Effective 2017, the
state will prohibit the sale of triclosan-based cleaning products for
the hands and body -- except those with FDA approval, such as Total.
Colgate Lobbied
“Colgate came in and lobbied, and said it’s a good product,” said John Marty, a state senator who sponsored the bill.
The
FDA, meanwhile, has vowed to deliver the monograph covering triclosan
in handsoaps -- the one it promised for the first time four decades ago
-- by 2016.
As part of that review, the agency will look at
recent safety data on triclosan, said Kweder, the deputy director of the
new drugs office. Kweder said the FDA doesn’t plan to revisit its Total
decision but that if it finds concern in its broader review, it could
look back into Total’s 1997 approval.
“But we would have to have a good reason to do that,” Kweder said.
(bloomberg)
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