As countries throughout Asia become increasingly reliant on
fossil fuels, more harmful mercury is finding its way into the fish we
eat. But
new research suggests people can limit their mercury consumption by eating less fish that dwell deeper in ocean.
Mercury Levels Predicted to Rise in Pacific Ocean Fish Aired 8/26/13
As countries throughout Asia become increasingly reliant on
fossil fuels, more harmful mercury is finding its way into the fish we
eat. But new research suggests one way people can limit their mercury
consumption: Eat more fish that dwell near the ocean surface.
Scientists already know that large fish tend to ingest more mercury than smaller fish. The
process of bioaccumulation accounts for how mercury gets amplified as it moves up the food chain.
But they’ve also noticed something that couldn’t be explained by
bioaccumulation. Fish from darker, deeper waters often contain more
mercury than similar
fish feeding higher up.
Now, thanks to a new study co-authored by Brian Popp of the
University of Hawaii, we now know why fish dwelling farther away from
the ocean surface consume more mercury. It has to do with sunlight,
which can actually help break up the harmful form of mercury that gets
into fish — and onto our plates.
"Reactions catalyzed by sunlight break down that organic mercury,"
Popp said. Understanding this phenomenon could help guide regulators’
seafood recommendations in coming decades, when mercury levels in fish are projected to spike.
Popp said, "If all things remain equal and there’s a continued
increase in emissions from power plants, projections show a
two-to-three-fold increase over the next roughly 20 years."
He added that getting tough on rising mercury requires getting tough on emissions in Asia.
"It’s not sufficient to simply clean up our backyard," Popp said. "It’s a global problem."
Until more countries adopt
strict mercury emission standards, Popp says seafood advisory committees should steer consumers toward fish from sunnier parts of the ocean.
http://www.kpbs.org/news/2013/aug/26/mercury-levels-predicte...S+News%3A+Science%29