All one ahupua‘a when
it comes to mercury
In 2001, kids playing in an old pumphouse found mercury and brought it back to their Halawa homes, sending many families to the hospital for treatment. Mercury is toxic even in such small amounts that lawyers wanted the housing complex declared a federal disaster area.
However, a new health advisory from the U.S. Food and Drug Administration and Environmental Protection Agency drives home the point that we are all exposing ourselves to this dangerous contaminant every time we eat fish. In fact, Hawaii's residents are exposed to more mercury than most Americans because of frequent fish consumption (two to four times the national average) and high levels of mercury in Hawaii's most popular fish. Using government statistics, more than 9 pounds of mercury was "caught" in Hawaii's most popular open-ocean fish in 2002 alone. Mercury is considered so poisonous that the FDA warns that even the small amount in mercury thermometers should be properly disposed of immediately if the thermometer breaks.
Mercury is naturally found in the environment, but more than half of global mercury emissions come from coal-fired power plants, waste incinerators, mining and industry. Although there are few of these sources in Hawaii, the mercury emitted from power plants around the Pacific still makes it into our ocean waters. Once in the ocean, mercury "biomagnifies" up the food chain -- every time a big fish eats a little fish it absorbs mercury into its own tissues. So, large predatory fish like shutome, kajiki, ahi, tombo, ono, opah and shark have the highest mercury levels.
Mercury is retained in our bodies for several months and can damage the brain, kidneys and other organs. Eating seafood is generally good for you, but the trick -- particularly for pregnant and nursing mothers (and thus young children and fetuses) -- is to pick seafood that is low in mercury. Shutome, kajiki and shark have the highest mercury levels and should be avoided by these groups. Ahi, tombo, ono and opah have elevated levels as well. The state Department of Health recommends eating smaller species like akule, mullet and opelu. Some imported fish, such as wild salmon from Alaska and farmed tilapia, are low in contaminants and ecologically friendly. For more information, read the DOH's "A Local Guide to Eating Fish Safely" and visit www.environmentaldefense.org/go/seafood.
When we eat from the ocean we take a bite from one big global ahupuaa, or watershed. Mercury from coal-fired power plants from Ohio to Osaka can find its way into our diet. So, like global warming, ending most mercury pollution is going to take a global solution. Nevertheless, the government should do all it can to protect us from this contaminant.
We should support members of Hawaii's congressional delegation as they fight for our health against a disastrous energy bill that subsidizes mercury-polluting industries, and we should send letters criticizing proposed regulations by the EPA that do too little, too late to reduce mercury pollution (actionnetwork.org/campaign/nationalmercury).
About the authors
Tim Male is an ecologist at Environmental Defense in Washington. He received his doctorate from the University of Hawaii and previously worked for the state Department of Land and Natural Resources. Timothy Fitzgerald is an oceans research associate at Environmental Defense in New York, and received his master's degree from the University of Hawaii. Rod Fujita is a marine ecologist at Environmental Defense and author of the book, "Heal the Oceans."