Mercury content of equisetum plants around mount st. Helens one year after the major eruption.
The mercury content of young Equisetum plants collected around Mount St. Helens was higher in the direction of Yakima and Toppenish, Washington (northeast to east-northeast), than at any other compass heading and was about 20 times that measured around Portland, Oregon. The increase in substratum mercury was not as pronounced as that in plants but was also higher toward the northeast, the direction taken by the May 1980 volcanic plume.
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