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Mercury tends to show up in strange places, like swordfish and sharks. Now researchers have detected small amounts of mercury in the fog that bathes the California redwoods, near Santa Cruz.
The mercury levels they've measured are in parts per trillion, orders of magnitude less than the more worrisome parts per million levels tracked by the EPA and FDA. So the fog is not dangerous. But it does contain four times as much mercury as local rainwater does.
And when the fog rolls in, it collects on redwood leaves, and drips to the ground, where it enters the food chain. Preliminary data suggest that during the foggy season, wolf spiders in the area see their mercury levels multiply by five. The findings were presented [by Peter Weiss-Penzias] at a meeting of the American Geophysical Union in San Francisco.
Researchers say the mercury in coastal fog probably comes from deep ocean waters, which well to the surface every summer. But its original source may be coal-burning power plants, or pollution from mercury mines dating back to the gold rush. Either way, it's a reminder that whatever we dump into the environment will probably pay us a return visit.
—Christopher Intagliata
[The above text is a transcript of this podcast.]
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5 Comments
Add CommentThere were other problems with fog in California from different locals. Near Santa Barbara the fog picks up hydrogen sulfide from methane seeps nearshore and it gets pretty acidic as well, plus there were local sources of mercury there which were natural and made worse by mining such as the deposits in the coastal mountains.
Reply | Report Abuse | Link to thisThat it would accumulate up the food chain is no surprise but I'd like to hear some long term implications. Probably take more work.
This reminds me of something someone said years ago:
Reply | Report Abuse | Link to this"You can't throw it away... There is no 'away'".
@bboyd3, tell my money that.
Reply | Report Abuse | Link to thisSo how do we get rid of it? Do we engineer some kind of mercury collecting salmonid, which amasses mercury in its tissues while at sea then swims home to its waste treatment plant where the mercury is extracted? Is there a way to extract mercury from sea water as part of the desalination process? Is there a way to chemically bind mercury and sink it into ocean sediments? Or do we need to start treating dead creatures high on the food chain as toxic waste?
Nice line! LOL. You can extract anything you want to from oceans. Just it will take forever. From what I read in the article, the amounts being dected are in nano-gram ranges. I once worked for a company that produced Arsine, the most toxic gas known. The 'safe' trace arsenic levels were lowered each time the detection levels were improved. The risks hadn't changed, but the science said the safe levels had to be reduced. Same here; the ability to detect mercury at lower and lower levels does not mean we are more at risk. Mercury on the beach doesn't bother me, but mercury in my favorite tuna salad just might if I thought about it.
Reply | Report Abuse | Link to thisjust read a summary from an article about engineering e-coli to express a protein that binds with a number of different mercury species. So we could line the guts of engineered fish with this bacteria. The great thing about salmon is that you release them, and they come back, that's if they aren't intercepted on the way. I guess that's a problem, you don't want your mercury concentrators to be eaten by other sea-life.
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