Toxic and mutagenic activity of water samples from natural sources of the Enbekshikazakh district of the Almaty

Abstract

The current ecological situation sharply raises the question of checking water sources for mutagenic,
genotoxic, and phytotoxic activity. An increase in human activity around water sources increases the
risk of surface water pollution by various emissions and wastes, an increase in the concentration of
various pollutants in the aquatic environment can lead to mutagenic activity of this source. Since the
rivers Esik, Turgen, and Lake Esik, located in the Enbekshikazakh district of the Almaty region, are close
to highways, various enterprises and proximity to human activities, the risk of pollution is continually
increasing. As a result of physicochemical analysis of the composition of water samples, an excess
of the maximum permissible concentration for manganese, lead, zinc, and cadmium was found. The
Allium-test revealed toxicity and mutagenicity of the studied water samples. The phytotoxic activity
was observed in the water of the River Esik, manifested in the inhibition of onion root growth. Cytotoxic
activity in the water of the rivers Esik, Turgen, and Lake Esik was manifested in a statistically significant
decrease (p≤0.05) in the mitotic index compared to the negative control (distilled water). A weak mutagenic activity was established in water samples from the river. Esik, Turgen and Lake Esik, manifested in
a statistically significant increase in the level of chromosomal aberrations in the cells of the root meristem
of onions when germinating in water from these water bodies, compared with negative control (p≤0.05).
Thus, the obtained results of the study of the toxic and mutagenic potential of natural surface waters from
water bodies located on the territory of the Enbekshikazakh district of the Almaty region indicate their
contamination with environmentally hazardous factors that pose a threat to biota and human health.
Key words: natural surface waters, heavy metals, Allium test, mitotic index, chromosomal
aberrations.