[Pharmwaste] The Cloudy Side of Sunscreens

[Tenace, Laurie]

http://pubs.acs.org/subscribe/journals/esthag-w/2006/jan/science/te_sunscreen
s.html


The cloudy side of sunscreens
New Swiss research shows that the same sunscreen compounds that protect us
from ultraviolet radiation could also be endocrine disruptors bioaccumulating
in fish.
In a study posted to ES&T's Research ASAP website today (10.1021/es052088s),
a team of scientists report high concentrations of two sunscreen ingredients
in fish tissue samples taken from rivers in northern Switzerland. The
findings imply that on a hot summer day, chances are that if people are
wearing sunscreen, it's also likely to be in their drinking water or fish
dinner too.

New research shows that the ingredients in sunscreens, which are suspected
endocrine disrupters, are bioaccumulating in fish. Although both Europe and
the U.S. have consumer-protection guidelines in place for many of these
UV-inhibitor products, regulatory agencies have placed less emphasis on the
environmental risks that they pose.Many of the lotions, lip balms, and other
cosmetics that we slather on to protect us from the deleterious effects of
too much sun exposure contain chemical compounds that absorb ultraviolet (UV)
radiation. Scientists suspect that some of these compounds are endocrine
disruptors. In both Europe and the U.S., consumer protection guidelines are
in place for many of these UV inhibitor products, but regulatory agencies
have placed less emphasis on the environmental risks that they pose.

Ubiquitous in the environment
The Swiss study shows that skin and lip-care products are nearly ubiquitous
in populated environments. When people swim, the UV filters in these products
can be transferred from their skin into lakes and streams. The chemicals also
wash off in the shower and are funneled to wastewater treatment plants, where
traces can escape via treated effluent into the environment.

Suncare and lip-care product sales constitute an estimated $1 billion
industry annually in the United States alone, according to market research.
And annual production figures for UV filters are estimated in the hundreds of
metric tons, according to a previous study on the chemical contents of
wastewater by the new study's corresponding author Marianne Balmer (Environ.
Sci. Technol. 2005, 39, 3013-3019). She conducted this latest study with a
team of chemists at the Swiss agriculture department's federal research
station (Agroscope FAW) in Wädenswil and the Swiss Federal Laboratories for
Materials Testing and Research's Laboratory of Organic Chemistry in
Dübendorf.

All of the 19 fish tested in the recent study had traces of two of the most
commonly used UV filters in Europe-4-MBC (4-methylbenzylidene camphor) and OC
(octocrylene). Both chemicals biodegrade slowly and can bioaccumulate,
according to the researchers.

Much higher levels in river fish
Compared to another FAW study that analyzed fish from remote Swiss mountain
lakes, the river fish accumulated much higher concentrations of both
chemicals (Environ. Sci. Technol. 2004, 38, 390-395). Lipid weight-based
concentrations of 4-MBC in the lake species-white fish (Coregonus) and roach
(Rutilus rutilus)- ranged from 20 to 170 parts-per-billion (ppb). The brown
trout (Salmo trutta fario) from the rivers tested in the current study had
concentrations ranging from 50 to 1,800 ppb. OC was mostly absent in the lake
fish study-done in conjunction with the Cantonal Food Inspectorate and
Institute of Environmental Chemistry at Umeá University- but was found in the
river fish at concentrations from 40 to 2,400 ppb.

One explanation for the higher concentrations is wastewater treatment plant
inputs, according to one of the report's coauthors, Hans-Rudolf Buser. All of
the fish tissue samples in the river study were taken less than 1 kilometer
(km) downstream of treatment plants that serve between 6,600 to 48,000
people.

The nearly 10-fold difference in concentrations among lake and river fish
sheds light on the environmental transport and fate of these chemicals. "The
study shows that UV filters were present in fish from rivers that receive
inputs of wastewater," Buser says. "One might argue, therefore, that aerial
transport is not a major pathway for the presence, or the distribution, of UV
filters in the environment and fish."

The Swiss government's work takes research on pharmaceuticals and personal
care products (PPCPs) in the environment to the next level in the U.S., says
Dana Kolpin, a hydrologist with the U.S. Geological Survey (USGS). Kolpin and
his colleagues monitor for nearly 100 such compounds in U.S. surface and
groundwaters in an effort to uncover the effects of these chemicals on
wildlife.

Although the U.S. EPA does not regulate any personal care products and 4-MBC
and OC are not currently on USGS's monitoring list, Kolpin says that Balmer's
work will help USGS decide how to prioritize further study on specific PPCPs.
USGS is modifying its sediment analysis method to include some UV inhibitors
and will soon establish a new monitoring protocol for these substances in
water, he adds.

According to Thomas Kupper of the Laboratory of Environmental Chemistry and
Ecotoxicology in Lausanne, Switzerland, treatment removes at least 90% of
4-MBC and OC from wastewater. However, levels entering the environment are so
high that the chemicals are still detectable in the effluent. In addition,
Kupper says that there are other inputs into the environment-and the human
body-besides direct and indirect contact with sunscreens, including UV
filters used as plastic stabilizers.

More data needed
Scientists and lawmakers in both the U.S. and Europe agree that more data is
needed on the uptake of these chemicals in specific species, discharge rates
from treatment plants, river and fish concentrations, and human health
effects.

4-MBC is a known endocrine disruptor and was detected in human milk in a 1997
German study, according to Margret Schlumpf, a toxicologist at the University
of Zürich's GREEN Tox, or Group for Reproductive, Endocrine, and
Environmental Toxicology, which researches the health effects of UV filters.
In studies with rats, Schlumpf has shown that some UV filters, including
4-MBC at levels as low as 7 milligrams per kilogram of body weight each day
(mg/kg/day), can alter reproductive function and affect birth weight and
postnatal survival rates (Toxicology 2004, 205, 113-122). The significantly
higher concentrations in river fish reported in the new study are shocking,
she says, and will help further her research.

"[Balmer] gives me data that helps me explain or support my findings," says
Schlumpf. "We think that there is not only one exposure to UV filters in
sunscreens by applying the créme on our skin, but there is a second or
additional way of exposure through the foodweb."

But industry sources maintain that UV filters do not produce harmful
endocrine disruption effects. Industry studies on the health impacts and
environmental fate of both 4-MBC and OC, which are currently under review by
European Union (EU) officials, have shown that there is no risk of these
chemicals contaminating the food chain at harmful levels, according to Gerald
Renner, director of science and research at the European Cosmetic Toiletry
and Perfumery Association.

Nevertheless, many manufacturers replaced 4-MBC with one of the other 25 UV
filters deemed safe under the European Union Cosmetics Directive [144KB PDF]
after a splash of bad publicity several years ago in Scandinavia, Renner
says. At issue were allegations that 4-MBC had estrogenic effects. A
subsequent evaluation by EU health officials determined that was not the
case, he adds.

Even if there are not measurable human and environmental health effects from
4-MBC and OC, these compounds could have negative synergistic consequences
when combined with other UV filters or chemicals found in PPCPs, according to
Christian Daughton, chief of EPA's Environmental Chemistry Branch at the
agency's National Exposure Research Laboratory in Las Vegas, Nevada. "If we
assume estrogenic activity is additive, we have to consider the combined
activities of 20 to 30 sunscreen agents," Daughton points out.

But Renner contends that a fear of UV filters is unhealthy. "Sunscreen phobia
counteracts cancer prevention," he says, adding that exposure to UV light
causes up to 20,000 skin cancer cases per 1 million people annually.

Meanwhile, Buser reports that environmental levels of 4-MBC have been
decreasing since 2002 in the Zürich area. The altered product compositions
seemed "to have an immediate effect on environmental concentrations," he
says.

Under EU cosmetics legislation, UV filters are tested for consumer safety,
but not environmental risks, says Christoph Studer of the Industrial
Chemicals Section of the Swiss Federal Office for the Environment, which
commissioned Balmer's study. "The results will show if more information is
needed on measurements in water, sediment and biota for the refinement of the
risk assessments," Studer says. -TASHA EICHENSEHER

Laurie J. Tenace
Environmental Specialist
Florida Department of Environmental Protection
2600 Blair Stone Road, MS 4555
Tallahassee, Florida 32399-2400
PH: (850) 245-8759
FAX: (850) 245-8811
Laurie.Tenace at dep.state.fl.us
 
view our mercury web pages at: 
http://www.dep.state.fl.us/waste/categories/mercury/default.htm