ABSTRACT
Objective In order to verify an alternative method for the skin corrosion test by using transcutaneous electrical resistance ( TER) test, and to optimize the implementation criteria in OECD TG 430 procedure. Methods According to the OECD TG 430 procedure, Wistar rat skin was used to test the TER values of 16 reference chemicals, and selected the most optimal standard via different implementation criteria. The program B was chosen to make inter-laboratory comparison between 5 laboratories by testing 11 chemicals, which were identified as the optimal standard. Results After the TER test, the result of corrosion test of 16 chemicals were accordant with the reference data ( Kappa value＝0. 64). The program B was the most optimal implementation criteria, and the specificity was 66. 7% and sensitivity was 100%. There were no significant differences between the corrosion estimations of 5 laboratories, and the concordance rate of the 5 laboratories was 72. 7%. Conclusions Transcutaneous electrical resistance (TER) test is an feasible and efficient tool for skin corrosion testing, and may become a good interim test to replace the in vivo test with this ex vivo test in cosmetics chemical safety assessment, thus, to reduce the animal usage in our country.
ABSTRACT
Objective To establish a rapid modified Local lymph node assay ( LLNA) for the sensitization and irritancy potential of chemicals, and evaluate cosmetics products. Methods 3 kinds of chemicals ( 2 , 4-Dinitrochlorobenzene ( DNCB) , Eugenol and Hexyl cinnamic aldehyde) and 3 kinds of cosmetics were selected.The dorsal sides of both ears of female BALB/c mice were treated with 25μL/ear of the test solutions on 3 consecutive days, and the thickness of each ear was measured.BrdU solution was injected inter-peritoneally on day 5.On day 6, each auricle was weighed, the bilateral draining auricular lymph nodes were excised and weighed, then made into single cell suspension.BrdU was measured by ELISA using a commercial kit.Results Ear swelling and auricle weight of DNCB ( 1.0%) , Eugenol ( 25% and 50%) and number 3 cream foundation increased significantly ( P <0.05 or P <0.01), which may be considered as irritants.The others were negative.For LLNA, three chemicals and number 3 cream foundation pretended positive.Conclusion The combined LLNA/ear swelling/ear weight assay appears to be a reliable predictor of sensitization and irritancy potential, and is expected to play an important role in safety evaluation of cosmetics.