Allium test genotoxicity data on water from river valley of Irtysh, West Siberia.

Assessment of genotoxicity of aquatic ecosystems is of great importance for environmental management and assessment of water ecological quality as well as health safety. Data on the genotoxicity of water in rivers of such a large region as Siberia are almost absent. Researchers do not pay enough attention to river floodplains, but such studies are important for assessing the ecological condition of the river system, because a significant part of toxic and genotoxic substances accumulates in the river floodplains A unique feature of the Ob-Irtysh interfluve is its vast floodplain, the largest in the Northern Hemisphere, providing key ecological functions of the territory. Originality of this river system lies not only in enormous size, but also in the exceptional duration and magnitude of spring-summer floods and the formation of complex biogeocenosis. In this data article we provide for the first time genotoxicity data for the Irtysh river valley (West Siberia) which is longest tributary river in the world. Water samples were collected from 5 sites: Irtysh river, floodplain sites (Jivaya river, Mukhrina river, Baybalak river) and terrace (Bog Mukhrino). Allium test was used to assess genotoxic effects. This method is one of the recommended bioassays for rapid genotoxicity screening of the water. Ana-telophase chromosomal aberration assay and micronuclei test were performed to determine genotoxic effects. Obtained data for mitotic index and other phase indexes. Data on water genotoxic effects are accompanied by data on physicochemical parameters. The data shows that the floodplain waters accumulate allochthonous organic matter, which is evidently supplied with high water. This determines the increased genotoxicity of floodplain waters. The data allow other researchers to conduct a comprehensive analysis of the genotoxicity of natural waters on the landscape gradient of a river valley (terrace-floodplain-river) and reveal possible causes of the observed effects.