The Perchlorate Study Group (PSG) submitted a data quality request for correction to the Environmental Protection Agency (EPA) December 3, 2003, challenging a number of documents used to assess implications of perchlorate ingestion. This is the third challenge EPA received on perchlorate. Perchlorate is a chemical found in rocket fuel and has contaminated drinking water near Department of Defense (DoD) sites in at least 22 states. Request for Reconsideration Of the four documents challenged in the request, OMB and EPA data quality guidelines only categorize three as “information.” This includes a disposition of comments and recommendations for the revision of the perchlorate toxicological review and risk characterization; the references associated with the disposition; and the compilation of comments received on the perchlorate risk characterization. The fourth document is a set of slides from an EPA presentation, however, the data quality guidelines are fairly clear in its exemption of oral presentations. EPA disseminated the three documents to the National Research Council Committee to Assess the Health Implications of Perchlorate Ingestion. PSG believes the documents violate the objectivity and reproducibility standards of the data quality guidelines. PSG also contends the challenged information is “influential” because any regulatory action addressing perchlorate levels in drinking water would be economically significant. Higher standards of reproducibility apply to influential information. Specifically, PSG contends the information violates data quality guidelines because various data are missing from a reference the perchlorate disposition relies upon, the Consultants in Veterinary Pathology (CVP). This includes high-resolution images, criteria used to assign identification numbers to data, details from the material and methods, and other data. Additionally, PSG claims there are discrepancies in EPA’s statistical analysis of CVP data and that tissue samples used in the CVP are not shown to comply with a certification process that is standard for third party samples. The challenge also asserts that two other references that the challenged information relies upon are incomplete. The request states the references did not fully disclose material information and results. Resubmission In a March 25 letter to EPA, PSG renewed its request for correction. EPA had not responded to the original request within 90 days, as required by the data quality guidelines. EPA sent an interim response March 31 stating the agency will need an additional 60 days to reach its decision on the petition. The Perchlorate Study Group is an alliance of manufacturers and users of perchlorate that claims its “sole interest is an accurate, fair and unbiased characterization of potential human health risks.” To read about the previous perchlorate data quality challenges, view OMB Watch’s analysis.