By Lauran Neergaard

WASHINGTON (AP) - Farm-raised salmon contain significantly more dioxins and other potentially cancer-causing pollutants than do salmon caught in the wild, says a major study that tested contaminants in fish bought around the world.

Salmon farmed in Northern Europe had the most contaminants, followed by
North America and Chile, according to the study released Thursday. It
blames the feed used on fish farms for concentrating the ocean
pollutants.

Eating more than a meal of farm-raised salmon per month, depending on
its country of origin, could slightly increase the risk of getting
cancer later in life, researchers conclude. They urge consumers to buy
wild salmon and recommend that farmers change fish feed.

But the Food and Drug Administration said the levels of pollutants
found
in salmon are too low for serious concern. The agency urged Americans
not to let the new research, reported Thursday in the journal Science,
frighten them into a diet change.

The debate is sure to confuse consumers, who long have been told to eat
fish at least twice a week because it helps prevent heart disease.
Indeed, salmon is usually listed as a top choice because it is
particularly high in heart-healthy omega-3 fatty acids and low in a
completely different seafood contaminant, mercury.

Moreover, most farm-raised salmon sold in the United States comes from
Chile - and the pollutant level in it was not too much higher than that
found in some wild-caught salmon.

The study ``will likely over-alarm people in this country,'' said Eric
Rimm of the Harvard School of Public Health, a specialist on nutrition
and chronic disease. ``To alarm people away from fish because of some
potential, at this point undocumented, risk of long-term cancer - that
does worry me.''

The study tested salmon raw, with the skin on. Removing the skin and
grilling it removes a significant amount of PCBs, dioxins and other
pollutants stored in fish fat, the FDA noted.

The average dioxin level in farmed-raised salmon was as 11 times higher
than that in wild salmon - 1.88 parts per billion compared with 0.17
ppb. For PCBs, the average was 36.6 ppb in farm-raised salmon and 4.75
in wild salmon.

The government does not have one set level of dioxins and PCBs that is
considered safe in foods.

``We are certainly not telling people not to eat fish. ... We're
telling
them to eat less farmed salmon,'' said David Carpenter of the
University
at Albany, N.Y., who tested 700 salmon from around the world.

In setting his consumption advice, Carpenter cited Environmental
Protection Agency guidelines that are far stricter than the FDA's legal
limits.

Farmed salmon eat lots of fish oil and meal made from just a few
species
of ocean fish, which concentrates the contaminants they are exposed to,
while wild salmon eat a greater variety, Carpenter explained.

The salmon farming industry points out that all the pollutant levels
are
well within the FDA's legal limits and says other foods eaten far more
often, such as beef, are greater sources of exposure.

Raising salmon in floating pens is an industry that began just two
decades ago but has helped the fish's popularity to soar, turning it
from a seasonal to a year-round commodity. More than half the world's
salmon now is farmed. Farm-raised salmon sells for about $4 or $5 a
pound compared with $15 for wild salmon, said Alex Trent of the trade
group Salmon of the Americas.

``These fish don't have to be contaminated,'' said Jane Houlihan of the
Environmental Working Group, which wants salmon farms to switch the
feed
they use.

Trent said many farmers in the United States, Canada and Chile are
slowly replacing some of the fish oil in salmon feed with soybean and
canola oil to address the pollutants.

``PCB levels are coming down 10 to 20 percent a year. Every year we
take
more steps,'' he said.

Farm-raised salmon contained significantly higher concentrations of 13
pollutants, including dioxins, released when industrial waste is
burned,
and PCBs, once widely used as insulating material, according to the
study.

Animals absorb those pollutants through the environment, storing them
in
fat that people then eat. High levels are believed to increase the risk
of certain cancers and, in pregnant or breast-feeding women, harm the
developing brains of fetuses and infants.

One in two Americans will die of cardiovascular disease, a far bigger
risk than the cancer concern, said nutritionist Alice Lichtenstein of
the Agriculture Department's Human Nutrition Research Center at Tufts
University.

Still, ``this was a beautiful study'' that does raise a concern that
needs more attention, she said. ``The bottom-line message is to
continue
to eat fish but consume a variety of different types.''

As for the geographic difference in contaminant levels, ocean pollution
follows a similar pattern. Europe was industrialized before North and
then South America, and presumably each region uses salmon feed made of
local ocean fish.

The study was funded by the Pew Charitable Trusts.

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