2011 Edition of the Drinking Water Standards and Health Adv isories 2011 Edition of the Drinking Water Standards and Health Advisories EPA 820-R-11-002 Office of Water U.S. Environmental Protection Agency Washington, DC Winter 2011 Date of update: January, 2011 Recycled/Recyclable Printed on paper that contains at least 50% recy cled fiber. iThe Drinking Water Standards and Health Adv isories Tables are revised periodically by EPA’s Office of Water in order to update RfD and Cancer values so that they are consistent with the most current Agency assessments of chemical contaminants that may occur in drinking water and to introduce new Health Advisories. The following information should be kept in mind when using the 2011 Edition of the Tables: Reference dose (RfD) values are updated to reflect the values in the Integrated Risk Information System (IRIS) and the Office of Pesticide Programs (OPP) Reregistration Eligibility Decisions (RED) Documents. The Drinking Water Equivalent Level (DWEL) has been adjusted accordingly. Thus, both the RfD and DWEL in the Tables differ from the values in the Health Advisory document when the IRIS or OPP RfD is more recent than the Health Advisory document value. RfD values from IRIS that differ from the values in the Health Advisory documents are presented in BOLD type. Values derived from the REDs are given in BOLD italics. For unregulated chemicals with a recent IRIS or OPP RfD, the lifetime Health Advisory is calculated from the DWEL using the relative source contribution value published in the Health Advisory document. For regulated chemicals, no lifetime value is provided in the Tables when the revised lifetime value would differ from the Maximum Contaminant ...
