The U.S. Environmental Protection Agency (EPA) has made a preliminary determination to regulate strontium in the nation's drinking water. Strontium is a naturally occurring element that, at elevated levels, can impact bone strength in people who do not consume enough calcium.
A regulatory determination is a formal decision on whether EPA should initiate a rulemaking process to regulate a specific contaminant. The Safe Drinking Water Act requires that every five years, EPA develop a contaminant candidate list and then make a regulatory determination for at least five contaminants on the list.
Based on available information, the agency has initially determined that strontium has adverse health effects. Strontium replaces calcium in bone, affecting skeletal development. Although strontium affects all life stages, infants, children and adolescents are of particular concern because their bones are developing. Strontium has been detected in 99% of public water systems and at levels of concern in 7% of public water systems in the country.
Four other contaminants (dimethoate, 1,3dinitrobenzene, terbufos, and terbufos sulfone) are either not found, or are found at low levels of occurrence in public water systems, thus requiring no regulation at this time.
These determinations are preliminary. EPA will evaluate public feedback following a 60-day public comment period and determine whether to issue a final determination to regulate strontium. If EPA makes such a determination, the agency will begin the process of developing a proposed rule, with hopes of publishing the final regulatory determinations in 2015.