Applicability of the proposed GHS subcategorization criterion for LLNA:BrdU-ELISA (OECD TG442B) to the CBA/J strain mouse.

The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) is a hazard classification and communication system for providing information on the safe handling of chemicals worldwide. In this study, we evaluated the applicability of the newly proposed GHS subcategorization criterion for murine local lymph node assay:2-bromodeoxyuridine enzyme-linked immunosorbent assay (LLNA:BrdU-ELISA), Category 1A:EC1.6 ≤6%, Category 1B:EC1.6 >6%, to data derived from LLNA:BrdU-ELISA performed in the CBA/J strain mouse. Fifteen chemicals categorized in GHS hazard Category 1 sensitizers listed in the LLNA performance standard were tested by LLNA:BrdU-ELISA in the CBA/J strain mouse and were classified according to the new criterion. The results revealed that all of the GHS 1A or 1B category chemicals classified according to the EC3 values derived from radioisotopic LLNA (LLNA-RI) could be correctly assigned into the respective 1A and 1B categories using the newly proposed GHS subclassification criterion. In addition, analysis of the correlation between the reported EC3 values and EC1.6 values derived from the LLNA:BrdU-ELISA performed in the CBA/J strain mouse confirmed the existence of a strong correlation (r = 0.9076, P < .0001). These findings suggest that the newly proposed GHS subcategorization criterion for LLNA:BrdU-ELISA is potentially applicable for practical use in GHS subcategorization.