By David Biello
March 13, 2008
Scientific American
Plastic imbued with clay nanoparticles helps make Miller Brewing Co. beer
bottles less likely to break as well as improves how long the brew lasts in
storage. Simply H's Toddler Health nutritional drink mix includes
300-nanometer (300 billionths of a meter) iron particles. And a wide range of
cooking and cleaning items now employ nanosize silver particles to kill
microbes.
Yet, the Washington, D.C.–based environmental group Friends of the Earth (FoE)
reports that none of the more than 100 food or food-related products it
identified that contain
nanoparticles—puny particles between 100 and one nanometers—bears a
warning label or has undergone safety testing by government agencies.
"Products created using
nanotechnology have entered the food chain," says report author Ian
Illuminato, FoE's health and environment lobbyist. "Preliminary studies
indicate there is a serious risk…. We should know that it's safe before we put
it in our food."
The report builds on several studies in recent years that have shown that some
nanoparticles may cause harm. A 2005 study in Environmental Science &
Technology showed that
zinc oxide nanoparticles were toxic to human lung cells in lab tests even
at low concentrations. Other studies have shown that tiny silver particles (15
nanometers) killed liver and brain cells from rats. "They are more chemically
reactive and more bioactive," Illuminato says, because of their size, which
allows them to easily penetrate organs and cells. "Products should be at least
labeled so consumers can choose whether they want to be part of this
experiment."
FoE says it is probably underestimating the number of foods and food products
containing the miniscule particles, because they depended on self-reporting by
companies and a
list of 600 nanotechnology products compiled by the
Woodrow Wilson International Center for
Scholars (a think thank created by Congress in 1968 to foster links
between scholars and politicians) as part of its project to study the
implications of nanotechnology.
The environmental group charged that the federal government has failed to
protect consumers from the potential dangers of
nanoparticles and called for a ban on their use in food and food-related
products until they have been thoroughly tested to rule out health risks.
The U.S. Food and Drug Administration (FDA) currently does not specifically
require
nanoparticles to be proved safe but does require manufacturers to provide
tests showing that the food goods employing them—be it beer or baby
products—are not harmful. "Industry would bear the burden of demonstrating the
safety of the material under its intended conditions of use," says FDA
spokesperson Christopher Kelly. "Nanoparticle versions of [FDA-approved]
materials may well be new materials" that would trigger new investigations,
"and this is considered on a case-by-case basis."
To date, there are few published industry, government or scientific studies on
the
health and environmental impacts of nanoparticles. Further complicating
the matter is the fact that nanoparticles have been in the food supply for
years. "Nanoparticles have been in food products for decades, we just never
realized they were there," says physicist Andrew Maynard, chief science
advisor to the Wilson Center project. "We need to better understand how nano
can be benign in foods, but [also] where the dangers are."
For example, it remains unclear whether nanoparticles used in food packaging
might
migrate or leach into food or beverages. And it is completely unknown what
impact a wide variety of these nanoparticles might have on human health.
A wide variety of government agencies, including the FDA and the U.S.
Environmental Protection Agency (EPA), have taken an interest in
nanotechnology. The federal government spent more than $1.4 billion on
nanotechnology research last year as part of the National Nanotechnology
Initiative, a joint effort of 25 federal agencies investigating the promise
and potential perils of the emerging technology. Of that, roughly $40 million
was devoted to health and safety research (an amount set to nearly double to
$76 million in the fiscal year 2009 proposed budget).
The FDA could not provide figures on how much it spends on assessing the
safety of nanoparticles.
The EPA received $8.6 million of that $40 million, some $3 million of which
went directly to labs to research potential
health and environmental risks, according to Jim Willis, director of the
EPA's Chemical Control Division.
The EPA and its counterparts in Canada, Europe, Asia and Australia also began
in February a three-year study into the effects of 14 nanomaterials—including
silver, iron and other elemental nanoparticles as well as
carbon
nanotubes and nanoballs. "Once we get the results of phase one, we'll look
at moving into more in-depth testing on some of those or maybe some other
nanomaterials," Willis says, adding that any new chemical submitted for
approval that contains 10 percent or more nanosize elements receives special
attention from EPA reviewers. "We've seen about 30 or so in the past three
years," he says.
In 2006 the EPA began to regulate nanosilver as a
pesticide under the Federal Insecticide, Fungicide and Rodenticide Act. As
a result, companies employing such nanosilver particles (as an antimicrobial
in a wide array of merchandise from computers to cooking pans) are required to
register them as pesticides. Last week, the agency fined computer equipment
maker IOGEAR of Irvine, Calif., $200,000 for failing to register the
antimicrobial nanosilver in some of its wireless computer keyboards and mouses.
In January the agency also asked companies that use nanoparticles to begin
voluntarily providing the results of any
health and safety studies they had conducted. Willis says that the EPA
will review company response to determine whether voluntary compliance is
enough this summer.
Friends of the Earth insists that such reporting should be mandatory, given
the potential risks. The lobby also says the definition of what constitutes a
nanosize particle should include anything 300 nanometers or smaller. But
the Wilson Center's Maynard notes it is the effect rather than the size that
is significant.
"It all comes down to the need for more research. We can't fly blind here. We
need to know what's going on," Maynard says. "There is no hard evidence that
nanomaterials in products on the market will harm humans or the environment,
but there is enough evidence to say that we need to reexamine.''
http://www.sciam.com/article.cfm?id=do-nanoparticles-in-food-pose-health-risk