Microbial mutagenicity assays have been completed for 24 aliquots. Four aliquots received at ILS from NTP contractors were evaluated for micronuclei frequency using slide-based peripheral blood smears. At ILS, a comparative study of MN enumeration in mice and rats by flow cytometry (FCM) and microscopy for 4 aliquots has been completed. Technology transfer and proficiency at ILS using a flow-based MN determination method has been demonstrated. Quantification of the fluorescence intensity for each MN as a potential marker for aneuploidy appears to be useful. CREST anti-kinetochore antibody analysis of samples fixed for flow cytometry analysis was performed for a known aneugenic chemical aliquot, and proved not to be successful. The Comet assay at ILS is being used in these same studies to assess tissue DNA damage; studies are complete in mice and rats for 4 aliquots. Samples have been received and are being processed for analysis using the sperm FISH CT8 assay in mice exposed to a single aliquot. Keywords Micronuclei; Ames test; salmonella; mutation
