Is Canned Tuna Safe to Eat?
Is canned tuna safe to eat?
Canned tuna is the most widely consumed fish in North
America. It’s a healthy alternative to meat, is high in protein, vitamin
B-12 and is full of omega-3 fatty acids. And it’s so convenient. The problem is
that tuna is also high in mercury. In fact, tuna is the most common
source of mercury contamination in our diets.
So is it safe to eat? The answer depends on a couple of
things: What type of canned tuna you choose and how often you choose to eat it.
Mercury concentrations are higher in species of tuna that
grow larger and live longer. In the grocery store, most tuna is either albacore
or skipjack.
Chunk white or solid white tuna is usually albacore, has the
highest mercury concentration among all canned tuna. The mercury concentrations
in albacore are almost three times the levels of chunk light tuna, which is
made from a much smaller species called skipjack. It can get a little confusing though because
tonno or “gourmet” tuna is made from a larger yellowfin species and can have
mercury levels similar to albacore.
Canned light tuna can also contain other
species of tuna pushing the mercury content higher. Over all canned tuna is
your best tuna option given that fresh tuna has mercury concentrations more
than twice that of canned albacore.
Last year the U.S. EPA (Environmental Protection Agency)
published tuna consumption guidelines. The agency’s recommendations are based
on the most common types of tuna consumed – chunk white and light - and also take
into consideration differences between children and adults (children and
pregnant women are more vulnerable to the effects of mercury poisoning.)
Safe consumption guidelines:
According to the EPA, children under six can safely eat
three 3oz portions of light tuna per month. Older children and adults can
safely eat light tuna up to once a week.
If you’re eating chunk white tuna the frequency drops to
once a month for young children, twice a month for older children and up to
three times a month for adults.
Environmental impact:
There is more to canned tuna than mercury poisoning. There
are significant environmental issues associated with the world’s appetite for
fresh and canned tuna. Most
skipjack is caught using large purse-seine nets which results in a lot of
bycatch, including other fish, sharks, rays, and sometimes whales and dolphins.
Dolphin-friendly labels don’t mean that dolphins weren’t killed while the tuna
was being fished it just means that fishermen used other fishing methods to try
to avoid killing dolphins.
Albacore
tuna is caught mostly using long line fishing (miles-long lines of baited
hooks). This method of fishing is also responsible for lots of bycatch,
including sharks, swordfish, turtles, and seabirds.
If you’re
looking for an environmentally-friendly choice of tuna, pole-and-line-caught is
the best option. Look fir canned tuna that has the Marine Stewardship Council sustainability certification.
So, canned
tuna is safe to consume in moderation, although if you’re going for
canned fish, salmon is a better option since it’s lower in mercury and higher
in healthy oils. Environmentally, canned salmon is a better option too.
For more helpful information on fish and seafood consumption visit Environmental Working Group's Guide to Seafood.
Great information Bridget. Thanks. Lots of research on this one.
ReplyDelete