Friday May 27 2011
Mercury-contaminated fish flop onto local tables
By: Sara Seyydin Journal Staff Writer
Study finds unsafe levels of consumption from the Sierra
Many local fisherman and their families are chowing down on fish, and unsafe amounts of mercury, from the Sierra Nevada region, according to a study released by The Sierra Fund. The survey, which was released May 19, found that over 90 percent of anglers report eating local fish in the past year. Another half of those planned to feed the fish to women and children at home, which are designated as sensitive populations. While many local fishermen are aware of mercury in Sierra waterways, some debate whether there should be more signage placed along rivers. Other question whether mercury levels really are a threat. The Sierra Fund science director, Dr. Carrie Monohan said the extremely high levels of mercury present in the Sierra are a result of the region’s past as an epicenter for gold mining. “Twenty-six million pounds were brought over the Sierra Nevada,” Monohan said. “Ten to 30 percent was lost to the environment because the process was so messy. I have sucked up mercury with a turkey baster out of the Bear River.” Monohan said that while there are visible pools of mercury in watersheds throughout the region, the only real threat to public health is through consuming fish. The mercury contained in fish is converted to methyl-mercury, which is dangerous for humans. “Methyl mercury is a neurotoxin that causes cognitive and muscular development delays. That includes the loss of coordination,” Monohan said. “Elemental mercury is not nearly as toxic as the methyl mercury we see in fish. Methyl mercury crosses the blood brain barrier.” Women and children are considered the most sensitive population according to Federal guidelines, but Monohan said she has seen men with mercury poisoning. The Sierra Fund’s study also stated that the anglers surveyed had a limited understanding of the health-hazards eating mercury-contaminated fish could pose. Bass and brown trout were identified as having the highest levels of consumption and mercury-levels. “The fish you want to be most concerned with are the large bass fish. They have been around longer and are at the top of the food chain and eat a lot of little fish,” Monohan said. “Reservoirs in the Yuba, Bear River and American River watersheds are all what I would call mercury hot spots.” Monohan said one issue raised by the survey was the lack of information posted at local fishing spots. The Sierra Fund recommended that existing information about mercury be posted at local fishing spots, along with state-issued safe eating guidelines. The Sierra Fund is also advocating for abandoned mine sites be cleaned up, so overall mercury levels will be reduced. Full-time Northern California fishing guide and author, JD Richey, said he practices catch and release 99 percent of the time, so the findings won’t impact him much. He does see many people eat what they catch from Sierra waterways, though. “It’s really too bad. It’s one of the cool things about going fishing — getting to have your outdoor adventure and bring something home to eat,” Richey said. “It sounds like that might not be the best idea though.” If people are going to eat their catch of the day, Richey recommends they gut the fish properly to limit some mercury exposure. “There is a red strip of meat along the lateral line where a lot of the toxins accumulate and you always want to cut that out,” Richey said. “You also want to cut the dark meat out.” Richey said that he has been aware of the higher-than-healthy mercury levels for awhile, but more information should be available to the public. “It sounds like something that should be posted at each boat ramp,” Richey said. “If you have it posted, then you could decide if you want to eat it.” John Wadden, owner of Will Fish Tackle in Auburn, said most the fish he catches and keeps are planted by hatcheries. That means the fish have been in the waterways for less time, and contain lower levels of mercury. Wadden said most of his customers seem to understand the risks. “Most of my customers have known that this has been a mining area for hundred of years and there was a ton of mercury dumped here that isn’t going away,” Wadden said. “Just limit your intake of it and I think we will be safe.” He also said it would be difficult to post warnings across the Sierra. “What are you going to do? Post at every access point? I don’t know if that’s possible,” Wadden said. “Maybe at some of the larger areas like Folsom Lake it would be reasonable.” Angler Mike Cunningham of Colfax fishes one of the most contaminated varieties of fish, striper bass. He said he eats them despite the warnings, though he does focus on eating young fish. “I’m really not that worried about the mercury,” Cunningham said. “If the mercury problem is so big, than why are the fish thriving?” Cunningham also said there is some skepticism in the fishing community about mercury-contamination. He is among the critics. “I’d like to see some proof about the mercury levels. I’d be very curious,” Cunningham said. “I think there might be a lot less than they say. I think that might surprise people. That’s just my guess.” Monohan said that the proof is there, but even more testing on local watersheds needs to be completed. So far, data shows that the Bear River Watershed, which includes Rollins Lake, Lake Combie and Camp Far West, has the highest mercury levels, according to Monohan. She said that when more data is collected more specific guidelines can be issued for the Sierra Nevada. General federal guidelines recommend that people eat no more than 12 ounces of fish per week. Sensitive populations are advised to eat no more than six ounces of fish per week. Monohan said overall, anglers appreciated The Sierra Fund’s investigation of the issue. “In general the response was gratitude and concern,” Monohan said. “People were thanking us for doing this and curious about the issues.” Reach Sara Seyydin at firstname.lastname@example.org.