This document has been prepared to allow the toxicological evaluation of the unregulated contaminant nadic methyl anhydride in a class with tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride in drinking water, as an extractant from one or more drinking water system components evaluated under NSF/ANSI 61 (2012), or as a contaminant in a drinking water treatment chemical evaluated under NSF/ANSI 60 (2011). Methyltetrahydrophthalic anhydride is used as a surrogate as it is the only class member having sufficient toxicological data to establish action levels. Both non-cancer and cancer endpoints have been considered, and risk assessment methodology developed by the U.S. Environmental Protection Agency (U.S. EPA) has been used.

Click here for an executive summary of this document. (PDF)