Fish in some lakes along the Coeur d’Alene River contain lead and cadmium in their flesh, a new study confirms.
Fillets from fish in one of three lakes studied also contain mercury.
Some fishermen and environmentalists say the results of the state study demonstrate the need for more tests and more public health warnings about eating fish from Kilarney, Medicine and Thompson lakes. They are particularly concerned about the metals found in perch, an abundant fish commonly caught by children.
State environmental and health officials urge a more cautious reaction, however, saying heavy metals in fish from these lakes is nothing new. And the most recent tests do not show alarming levels of the toxins, they say.
The newest study sampled bullhead, pike and perch in the three lakes in 1995 and 1996. It found lead levels ranging from less than .05 parts per million to 2.4 parts per million. Cadmium hit a maximum of .16 parts per million.
The mercury results for bullhead show an average of .06 parts per million. Mercury tests are not yet complete for perch and pike.
Researchers have had some evidence for years that fish from the so-called chain lakes, east of Lake Coeur d’Alene, contain at least traces of heavy metals. Mine tailings, high in zinc, lead and cadmium, were dumped into the South Fork of the Coeur d’Alene River and onto the flood plain for nearly 100 years. Floods typically carry some of the mine tailings from the South Fork of the Coeur d’Alene River into the lakes.
The mercury, found in Kilarney Lake, however, is not mining waste, but comes from a natural source, state officials say.
Earlier studies sampled relatively few fish. So the Idaho Division of Environmental Quality and the Coeur d’Alene Tribe decided “let’s do a study that nails this down once and for all,” said Geoff Harvey, of Environmental Quality.
Researchers used rigorous quality control to make sure none of the fish were contaminated when they were caught and tested, Harvey said. When numbers from the most recent study are analyzed later this summer, the state of Idaho intends to issue new guidelines on how much fish from the chain lakes can be safely consumed.
At first pass, state officials are not concerned.
“Based on preliminary data, these fish don’t appear to be an extreme health risk,” said Brian Abbott, public health toxicologist with the state Bureau of Environmental Health and Safety. “I think what we will find is there is a safe level where you can consume these fish.”
For example, the mercury numbers are one-sixth of the level that would elicit concern from the state Bureau of Environmental Health, Abbott said. “We’ve seen much higher levels of mercury in the Snake River and Brownlee Reservoir,” Abbott said.
The Agency for Toxic Substances and Disease Registry has agreed to help study the lead results to determine safe consumption levels.
Abbott’s only caution is that some of the fish sampled are fairly small and that “could skew the data to make the fish look safe.” Smaller fish are younger and therefore haven’t had the same opportunity to ingest as much of the metals.
“Most people won’t keep such small fish,” Abbott said.
Final results will identify the amount of heavy metals found in each size of fish, Harvey said.
The mining industry is pleased with the study. “I feel confident and I think the companies feel confident that the results will show people who are eating fish like they are now won’t have a problem,” said Holly Houston, an industry spokeswoman in Coeur d’Alene.
The Idaho Conservation League is less satisfied.
“I don’t think Boise will consider a lot of important factors,” said the ICL’s Scott Brown, such as the effects of ingesting all three heavy metals.
In addition, he said, “they downplay the risks by using the average - if you eat one fish or two fish.”
EPA guidelines say it appears lead can affect a child’s neurological development at such low levels “as to be essentially without a threshold.”
“People need to know there’s a problem in order to make an informed decision,” Brown said. He and others are pushing for making the problems with the contaminated fish more widely known.
Ron Glackin, a fisherman who moved here from Nevada three years ago for the angling, agrees. Glackin and three friends pulled a 26-pound pike out of Cougar Bay, on Lake Coeur d’Alene in February and ended up giving six of the pike fillets to Brown for testing.
The results show some lead and cadmium in the flesh, according to Brown.
State officials say that one fish taken without rigorous quality control techniques isn’t a significant indication of anything. Testing equipment is so sensitive, that if the fishermen used a lead sinker to pull in the pike, it would leave enough residue to be picked up in the lab.
Even so, Glackin believes people are far too uninformed.
“Being a new guy to the area, I didn’t know there was contamination in the South Fork or that the chain lakes were contaminated,” Glackin said.
He points to a pamphlet, put out by Panhandle Health District, that warns people about fish consumption and soil contamination in the Coeur d’Alene River system. “The information is there, but it hasn’t been circulated,” Glackin said. “I’ve never met anyone who has seen that pamphlet.”
Glackin gave the pike that tested positive for lead and cadmium to a friend who in turn gave it to his banker. The banker distributed it among his staff.
That makes a strong case for better distribution of information on the fish, Glackin said. People might still choose to eat it, but they need to consider the danger from heavy metals to children and pregnant women.
The health district acknowledges word of lead contamination isn’t well disseminated beyond the Bunker Hill Superfund site in the Silver Valley. The agency had plans to use an EPA grant to put signs and pamphlet racks at every boat launch and public access point on the chain lakes this summer.
The EPA instead insisted the money be used to test children living in homes that potentially have leadbased paint.
Panhandle Health also wanted to sample beaches around Lake Coeur d’Alene, but doesn’t have the money, said Ken Babin, a senior environmental health specialist.
Babin also supports extending fish analysis to Lake Coeur d’Alene.
“The question has come up several times,” he said. “The answers have not come up because, to the best of my knowledge, there’s been no definitive study of fish in Lake Coeur d’Alene.”
, DataTimes ILLUSTRATION: Color photo Map: Contaminated fish caught in chain lakes
MEMO: This sidebar appeared with the story: HEALTH EFFECTS Long-term ingestion of low-levels of cadmium, lead and mercury causes a variety of health problems. Children and pregnant women are most susceptible: Cadmium occurs naturally and is commonly found in coal, fertilizer, batteries, pigments and plastics. It accumulates in the body. People ingest cadmium by breathing contaminated air, from food especially shellfish and liver cigarette smoking or drinking polluted water. It damages the lungs, kidneys, digestive tract and bones. Lead is most commonly found in batteries, ammunition, roofing and metal products. It has been reduced in gasoline, paint, ceramics, caulking and solder. People most get lead from breathing air containing tobacco smoke or lead-laden dust and from ingesting contaminated food or water. Children take in lead while playing in contaminated soil or eating chips of lead-based paint. Lead is a poison to every part of the body. It particularly damages the nervous system, kidneys and immune system. Mercury is a naturally occurring metal that is the byproduct of mining in places other than the Silver Valley. Automobile emissions, fungicides and burning coal all give off mercury. It often appears in reservoir water after an area is flooded by a dam. People ingest mercury from contaminated food and drinking water. Mercury may damage the brain, kidney and developing fetuses. -Ken Olsen
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