CYTOTOXIC AND GENOTOXIC ASSESSMENT OF SEWAGE TREATMENT PLANT AT SHER-I-KASHMIR INSTITUTE OF MEDICAL SCIENCES(SKIMS) SOURA, SRINAGAR BY USING Allium CepaTest (original) (raw)

2020, Journal of Experimental Biology and Agricultural Sciences

Cyto-genotoxicity of hospital effluents collected from sewage treatment plant of SKIMS, was investigated using USEPA recommended Allium cepa test. Heterogeneous samples of both untreated and treated effluents were collected from the STP twice a day for three months and designated as complex mixture. Before measuring the root length of the onion bulbs, A. cepa plants were exposed to 25%, 50% and 100% concentrations for both untreated and treated effluent samples in the dark for 72hrs. Significant results were observed in the root length evaluation and chromosomal aberration evaluation tests. Untreated effluent seems to be the most toxic on the root length of the A.cepa than treated samples. The lowest mean root length of onion bulbs was observed in untreated samples at 100% concentration which is found to be 0.61±0.28, 0.95±0.21 and 1.16± 0.43 cm for first, second and third day respectively. Untreated sample from STP of SKIMS at 100% concentration gave the lowest mitotic index (MI) value of 4.56±1.44 while as 50% and 25% concentration shows MI values of 16.32±2.09 and 27.08±6.07 respectively. Likewise, treated samples show mitotic index (MI) values of 18.2±4.65, 3.96±5.54 and 2.01±2.91 at 25%, 50% and 100%. The squash preparations from root tip cells of treated A. cepa bulbs revealed different types of chromosomal aberrations such as metaphase stickiness, chromosomal breaks, c-mitosis, anaphase bridges and anaphase stickiness, indicating environmental toxicity risk. The treated effluent samples were found to be less genotoxic and cytotoxic, thus inferring that genotoxicity is reduced after the treatment process and A. cepa test has proved to be an effective tool in monitoring hospital effluents before beingdischarged into the environment.