Hospital waste: impact on Allium cepa cells

Abstract

The dumping of chemical substances, from urban, industrial and hospital waste, is the main responsible for the high concentrations of toxic substances in the environment. The adverse effects and risks that these substances may cause to the ecosystem have become the target of research in the scientific environment. The chemical substances present in tailings can be metabolized, stored as well as interact directly with the DNA of eukaryotic cells promoting pre-oncogenic events. To assess the impact of so-called emerging contaminants (EDC's) on the genome of eukaryotes, it is possible to use micronucleus (MN) and nuclear abnormalities (NA) tests through onion root (Allium cepa) meristematic cells. The objective of this research was to investigate the cellular, genotoxic and clastogenic alterations in onion root meristematic cells, through exposure in three hospital waste sampling efforts at three different times. The collected samples were analyzed in a gas chromatograph coupled to a mass spectrometer (GC-MS QP 2010) in order to qualify the constituents present in the tailings. By analyzing semi-permanent slides stained by the Shiff method, the nuclear and micronucleus abnormalities were computed in 3000 Allium cepa meristematic cells exposed to hospital waste for 96 hours. The results obtained show that the calculated MI (Mitotic Index) of the cells submitted to the waste were significantly lower when compared to the negative control group. There is also an important correlation between mitotic index and MN appearance. In the GC-MS analysis, several main peaks were observed and different retention times were identified. In treatment 1 T (3.44) and treatment 2, T (3.47), Propoxur was one of the products found that offers clastogenic potential as it is a synthetic carbamate, composed of aromatic ether and acetylcholinesterase inhibitor, widely used as a pesticide. The results show that the waste from the hospital under study has cytotoxic and genotoxic potential.

Keywords

• Allium cepa
• Emerging contaminants
• Micronucleus