Font ResizeMill Creek near Moab is a popular fishing stream, but tests of two fish taken from it have shown high levels of toxic mercury.
For angler Pete Parry, that's worrisome.
"I'm concerned about it because there are some people around here who depend on [Mill Creek fish] to supplement their diet," says Pete Parry, 73. "It does need to be looked at."
Parry's comment points to the task ahead for state officials gearing up for a major study of mercury levels in Utah fish. Like almost all Western states that already have tested their fish, Utah officials will have to weigh issues of how to design the research, how extensive warnings are issued and the effects on public health, as well as the nutritional needs of those who consume the fish.
This week, officials from the state's Water Quality and Wildlife Resources divisions will meet with a state health lab epidemiologist to decide how to do the science that could justify mercury advisories, says Water Quality chief Walt Baker.
"What is the breadth of information we need - how much data to establish a fish advisory?" he says. "I'm going to rely heavily on the Health Department to let them do the heavy lifting on that."
Mercury occurs naturally in the environment but also is released into the atmosphere from coal-fired power plants and can come to Utah from as far away as China. In addition,
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Mercury falls to the Earth in rain and accumulates in the muscle of fish. It affects the human nervous system, and is most harmful to fetuses and young children because it can cause developmental and neurological problems. Recent studies have linked mercury exposure to autism, Alzheimer's disease and increased risk of heart disease in men.
About 80 percent of the nation's fish consumption advisories are related to mercury, though there also are advisories for other toxic substances. The federal Environmental Protection Agency and Food and Drug Administration provide guidelines for advisory programs, though each state is left to figure out how to craft them - or whether to bother with them at all.
All but five states already have such programs in place. In the West, only Utah and Wyoming don't have mercury-related fish advisories.
In New Mexico, where three state agencies have had mercury-related fish advisories in place for nearly 30 years, the warnings are tailored to each worrisome fish species in each affected water body.
Marcy Leavitt, head of New Mexico's Environmental Department Surface Water Control Bureau, says that in the early 1990s the state started working in earnest on mercury-related fish advisories, focusing especially on rural areas where people depend more on eating the fish they catch.
In Idaho, which has been posting the dietary advice since 1997, the advisories are less specific, but were developed with an eye to protecting 95 percent of the population by gearing surveys and science to people who depend upon fish for food, officials say.
The advisories resulted from a partnership between various state offices and the U.S. Geological Survey.
"We're trying to pick away at the water bodies as best we can with the partners we have," says Elke Shaw-Tulloch, Community and Environmental Health bureau chief.
Montana and Washington have issued advisories for all their states' lakes, reservoirs and streams. But in Alaska, where fish are virtually the only protein source for a large segment of the population, agencies have taken a strong stand in favor of unlimited fish consumption.
The eat-more-fish advisory, issued in 2001 by the state's health department, came after rigorous testing for mercury in water, fish and humans. While the results showed the toxic element present above accepted standards in some cases, state and tribal officials determined fish consumption was too critical to public health and to tribal culture to issue any warnings.
"Before you start making recommendations about people limiting food, you need to think about the benefits of the food," says Scott Arnold, an environmental toxicologist with the Alaska Section of Epidemiology. "People should use everything they can to make their own decisions. Our approach reflects what the public health community in Alaska believes."
What people do with the advisories is difficult to assess, says Paul Jakus, director of Utah State University's economics department graduate programs.
"It's just advice," says Jakus, who will participate in a global conference on societal consequences of mercury pollution next year in Madison, Wis. "People can ignore it, or they can even overreact."
In one study of fishers in the Chesapeake region, Jakus and his co-researchers found that while some people never eat the fish they catch, 80 percent of people who weren't aware of advisories ate their catch compared to 60 percent who knew of advisories. That translates to a 25 percent reduction in consumption, he says.
But that study was only a snapshot, and doesn't get at people's behavior over time. Part of the problem, Jakus says, is "people are getting a mixed message: Fish is good for you. It's brain food. But you don't want too much."
EPA assessments of 170 fish caught in Utah reservoirs, lakes and streams from 2000 to 2002 turned up four fish with mercury in their tissues above the EPA's body weight standard. That's not enough evidence to warrant an advisory.
Wayne Ball, a toxicologist and program manager for the Utah Health Department's environmental epidemiology program, admits there has not been adequate testing of fish in Utah's waterways.
"It's always a funding issue," Ball says. "The limited data we have to date indicate it's not an issue, but we all realize that's limited data and more testing needs to be done."
That testing is expensive. Though Ball isn't sure what the mercury assessments would cost, he says testing for arsenic cost $400 per fish. Mercury tests would be at least as expensive. To be statistically reliable, the lab would have to assess at least five fish per species per weight range to have a reliable statistical sample, he says.
