Appendix: Author’s opinion

Code	Author’s Opinion for Each Site	
+	Author in general literature evaluated the site as positive.	
–	In the general literature author evaluated the site as negative.  For NCI bioassays the opinion “not carcinogenic” and for NTP the evaluation is “no evidence of carcinogenic activity”, i.e. “studies that are interpreted as showing no chemically related increases in malignant or benign neoplasms.” 	
blank	For NCI/NTP and general literature:  a site for which no opinion is stated.	
a	For NCI Technical Reports the “a” opinion corresponds to an evaluation that tumors were “associated” with compound administration.  The “a” opinion generally corresponds to an NTP-reassigned level of “equivocal” for these NCI bioassays.	
c	The NCI evaluation is “carcinogenic” or the NTP evaluation is “clear evidence of carcinogenic activity”, i.e.  “studies that are interpreted as showing a dose-related (i) increase of malignant neoplasms, (ii) increase of a combination of malignant and benign neoplasms, or (iii) marked increase of benign neoplasms if there is an indication from this or other studies of the ability of such tumors to progress to malignancy.”	
e	NTP evaluation is “equivocal evidence of carcinogenic activity”, i.e. “studies that are interpreted as showing a marginal increase of neoplasms that may be chemically related.”	
p	NTP evaluation is “some evidence of carcinogenic activity”, i.e. “studies that are interpreted as showing a chemically related increased incidence of neoplasms (malignant, benign, or combined) in which the strength of the response is less than that required for clear evidence.”	
i	NTP evaluation is inadequate, i.e. “studies that, because of major qualitative or quantitative limitations, cannot be interpreted as valid for showing either the presence or absence of carcinogenic activity.”