In October 1999, the Department of Toxic Substances Control (DTSC) released its report of an inquiry into the California Department of Health Services (DHS) Cancer Registry Studies. DTSC found no evidence of elevated cancer rates surrounding SSFL. The final report was released in August 1999.
DTSC also hired an expert panel of epidemiologists to review three earlier state cancer studies. The expert panel report was released in June 1999. The expert panel concluded "Whereas there were some differences in the geographic areas, time periods, case definitions, and level of signifigance used in these three studies, the combined evidence from all three does not indicate an increased rate of cancer incidence in the regions examined."