Cytotoxicity and genotoxicity of Guaribas river water (Piauí, Brazil), influenced by anthropogenic action

Abstract

In general, tropical rivers have a great impact on human activities. Bioaccumulation of toxins is a worldwide problem nowadays and has been, historically, overlooked by the supervisory authorities. This study evaluated cytogenotoxic effects of Guaribas river (a Brazilian river) water during dry and rainy seasons of 2014 by using the Allium cepa test system. The toxicogenetic variables, including root growth, mitotic index, and chromosomal aberrations, were analyzed in meristematic cells of A. cepa exposed to water samples taken from the up-, within, and downstream of the city Picos (state: Piauí). The physical-chemical parameters were also analyzed to explain water quality and possible anthropogenic action. Additionally, the presence of heavy metals was also analyzed to explain water quality and possible damaging effects on eukaryotic cells. The results suggest that the river water exerted cytotoxic, mutagenic, and genotoxic effects, regardless of the seasons. In addition, Guaribas river presented physico-chemical values outside the Brazilian laws, which can be a characteristic of human pollution (domestic sewage, industrial, and local agriculture). The genetic damage was positively correlated with higher levels of heavy metals. The pollution of the Guaribas river water may link to the chemical contamination, including the action of heavy metals and their impacts on genetic instability in the aquatic ecosystem. In conclusion, necessary steps should be taken into account for further toxicogenetic studies of the Guaribas river water, as it has an influence in human health of the same region of Brazil.

Screening of Asa River water in Ilorin, Kwara State, Nigeria for available pollutants and its effects on mitosis and chromosomes morphology in Allium cepa cells

“…The xed root tips were rinsed with distilled water and then hydrolyzed in 1N HCL for 10 minutes at 60°C. Slides were prepared and observed under the light microscope (CH-China) using oil immersion objective lens to score dividing cells and chromosomal aberrations as previously described by de Castro e Sousa et al [14] and Akinboro et al [27]. Root length from the remaining six onions was measured with a ruler and recorded in centimeter to determine toxicity level of the water samples to A. cepa roots as described before by Akinboro and Bakare [28], Feretti et al [29] and Verma and Srivastava [30].…”

“…Bhat et al [12] stated that it can be used to screen cytogenotoxicity of single and complex chemicals in industrial wastes. The Allium cepa assay was employed to evaluate cytogenotxicity of Sungai Dua river water in Pulau Pinang, Malaysia and Guaribas river water in Piauí, Brazil [13,14]. Other genetic models such as Ames test, SOS/Umu test, comet assay and micronucleus test have also been employed in studying potential genotoxicity and mutagenicity of Organochlorine Pesticides (OCPs), their degradation products, and Polycyclic Aromatic Hydrocarbons (PHAs) in river surface waters in Central Chile, Shanghai, China and Adige river basin [1,15,16,17].…”

Effect of land-use pattern on the physicochemical and genotoxic properties of water in a low-order stream in Central Brazil

“…There is a correlation of 82% between the A. cepa test and the carcinogenicity test in rodents, and when compared with the prokaryotic model, A. cepa is more sensitive than the Ames test (Rank and Nielsen, 1994). The A. cepa test has been validated by the United Nations Environmental Program (UNEP), the World Health Organization (WHO) and the US Environmental Protection Agency (USEPA) as an excellent genetic model for the detection of genotoxicants and is frequently used in environmental monitoring studies (Leme and Marin-Morales, 2009;Sousa et al, 2017;Düsman et al, 2014;Silva et al, 2018;Bollani et al, 2018).…”