Our Fog, Does It Carry Poison?

The beautiful North Coast fog rises in wisps from the folds and crevices of our hills.  Like the breath of Humboldt itself it sighs upwards and slides sideways–and it may be carrying methylmercury, a toxicant that can build up in lifeforms.  According to yesterday’s New York Times new research from Santa Cruz University shows a troubling amount of it is carried by fog into central California coastal areas.

Mercury, a neurotoxin, occurs naturally in air, water and soil, and coal releases it when it is burned. Bacteria in soil and sediments convert mercury to methylmercury, which is both organic and soluble in water — a potent combination, Dr. Weiss-Penzias said. “It can be in water, taken up by organisms, stored in fatty tissues and cross the blood-brain barrier,” which prevents most other toxins from entering the brain, he explained.

When animals higher up in the food chain eat smaller organisms, they take up methylmercury, too. Moving up the food chain, methylmercury concentrations increase, in a process known as bioaccumulation.

Now the concentrations of methylmercury are not dangerous for us to breath in but the accumulations in our watersheds could be of concern. The samples taken around Monterey Bay last summer show amounts that are “five times higher than the highest levels previously recorded in rainwater.” This has troubling implications for us here on the North Coast.  I recommend reading the rest of the Times’ article.