Cytogenotoxicity assessment in Allium cepa roots exposed to phytoremidiated Used Lubricant Oil (ULO) contaminated soil

Abstract

The present study assessed the cytogenotoxicity in Allium cepa roots exposed to phytoremidiated Used Lubricant Oil (ULO) contaminated soil. The study involved a pot experiment of marigold (Tagetes erecta L.) seeds planted in six different concentrations of ULO-contaminated soil (0%, 1%, 2%, 3%, 5%, and 8% on w/w basis). A control series without seeds was also carried out and all experiments were triplicated. The experiment duration was 90 days with regular watering and under sunlight exposure. At 30, 60 and 90 days, A. cepa root meristems were examined for interphase cells, mitotic cell division stages, and the occurrence of nuclear and chromosomal abnormalities by exposing germinated root meristems of A. cepa to phytoremidiated ULO contaminated soil for 96 hrs. Descriptive statistics in MINITAB-19 software were used for data analysis. The results revealed decreased mitotic index with increasing ULO contamination levels and increased occurrences of chromosomal aberrations including breaks, vagrant chromosomes, chromosomal bridges, and polar slips. Nuclear abnormalities, including nuclear buds, bi-nuclei, and condensed nuclei, also increased with ULO concentration. However, all the parameters tested from phytoremidiated ULO contaminated soil showed comparatively low values with their respective controls. Overall, the present study provided important insights on the cytogenotoxicity of phytoremidiated ULO-contaminated soil in A. cepa roots highlighting potential health risks associated with ULO pollution in the environment. Further studies are recommended to develop targeted and sustainable mitigation approaches for ULO contamination, safeguarding ecosystems and human well-being.