Abstract:
Awba Dam reservoir is an important source of domestic water supply in the University of Ibadan, Nigeria.
It receives both point and non-point sources of untreated sewage and wastewaters from student and staff
residences, research laboratories and surrounding farmlands. Toxicological evidence on the pollution
status of the dam are on the increase. In this study, we investigated the cytotoxic and genotoxic effects of
Awba Dam water using the Allium cepa and murine sperm morphology assays. We also evaluated
systemic toxicity in mice using alterations in haematological, serum hepatic biochemical and
histopathological parameters. Bi-monthly composite water samples were collected from the Dam from
June – September, 2017. Each sample was used in the A. cepa root growth inhibition and chromosome
aberration test, and was administered as drinking water to groups of male Swiss albino mice for 35, 70
and 105 days. Tap water from underground source was used as negative control. There was significant
(p<0.05) mitotic inhibition and induction of different types of chromosome aberrations in A. cepa. At the
exposure periods in mice, there was significant (p<0.05) increase in frequencies of abnormal sperm cells,
alterations in haematological parameters and significant (p<0.05) increase in the levels of alanine
aminotransferase and aspartate aminotransferase when compared with the corresponding negative
controls. Histopathological alterations, including degeneration, congestions and inflammations were
observed in sections of liver and kidney. Pb, Cd, Ni and Fe in the water samples contributed to the
observed toxicity. Awba Dam water contains constituents that induced genetic and systemic damage in
mice and A. cepa. This is of public health importance to resident biota, and other organisms including man
along the food chain.
