Thanks to the Safe Drinking Water Act of 1974, every five years the Environmental Protection Agency identifies new contaminants in our drinking water supply and determines if they should be regulated. This year, of the handful of contaminants assessed, the EPA made a preliminary determination to regulate strontium.
Many of us are familiar with radioactive strontium, a byproduct of nuclear weapons testing. But the strontium that the EPA found polluting drinking water supplies is a naturally-occurring form of the element. When it dissolves out of bedrock, it can pollute wells. Strontium-contaminated water has no taste or odor.
Unfortunately, our bodies mistake strontium for calcium. It accumulates in our bones, with excess consumption affecting bone density. Infants, children, and adolescents are most at risk because their skeletons are still developing and they are most prone to calcium deficiencies. “Strontium rickets” causes malformations in the long bones of the legs, causing bowlegs and knock knees. Tooth enamel is also impacted.
The problem is pervasive. Of the 93 million people that rely on community groundwater systems in the nation, the EPA found that 10 million may be exposed to strontium concentrations in excess of the new health reference level. Wisconsin has been particularly hard hit. In northeastern parts of the state, some 63% of wells tested had unacceptable strontium levels.
Currently, the EPA is field-testing treatment technologies to assess the effectiveness of strontium removal from water systems. If regulation is pursued, it could take several years to enact.
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EPA weighs new move to regulate drinking water
EPA takes step in regulating drinking water
Photo, posted October 8, 2010, courtesy of Steve Johnson via Flickr.
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Earth Wise is a production of WAMC Northeast Public Radio.