Ability of Allium cepa L. root tips and Tradescantia pallida var. purpurea in N-nitrosodiethylamine genotoxicity and mutagenicity evaluation

n-nitroso compounds, such as n-nitrosodiethylamine (ndea), can be formed by the reaction of secundary amines with nitrosating agents, and are suspected to be involved in tumors in humans. ndea has been considered a weak carcinogen in genotoxic assays probably due to the inefficient nitrosamine activation system that is used and/or to the efficient repair system. in this work, we evaluated the sensibility of allium cepa l. root tips and tradescantia stamen hair mutation assay (trad-sh) using tradescantia pallida var. purpurea for ndea (0.1; 0.5; 5 and 25mm) genotoxicity and mutagenicity induction. allium cepa l. was treated with different ndea concentrations for 3h, for 3 consecutive days, including negative control (distilled water) and positive control maleic hydrazide (mh 30mg/ml). after treatment, the roots were hydrolyzed, squashed, and the mitotic index (mi) and cytological abnormalities were scored. the results revealed a cytostatic effect of ndea (0.5 and 5mm), showing a significant reduction in the mi. chromosome stickiness suggests a ndea toxic effect. t. pallida purpurea did not respond to mutagens with a dose-dependent pattern. in conclusion, our study indicates that the root tips of allium cepa l. have sensibility to detect ndea genotoxicity, but not for trad-sh test.