Assessment of environmental hazards of potentially toxic elements arsenic, cadmium and nickel in water and sediments of Dez River

Abstract

Introduction: Potentially toxic elements are dangerous and toxic pollutants that can enter
the food chain of living organisms and eventually cause disease and cancer in humans.
This research was conducted with the aim of analyzing environmental pollution indicators
in the water and sediments of the potentially toxic elements of arsenic, cadmium and nickel
in the Dez River.
Materials & methods: The location of water and sediment sampling in this research was
in Dezful city. 30 water samples and 30 sediment samples were collected from each station,
and a total of 120 water and sediment samples of Dezful River were prepared from two
studied stations. Sampling of water and sediments was done according to ASTM method.
The measurement of the studied elements was done by atomic absorption method and
graphite and hydride furnace system with the help of Perkin Elmer 4100 device.
Results: The results of the t-test of water toxic elements showed that there was a significant
difference between cadmium and arsenic in the two studied stations of the Dez River
(P<0.05), but there was a significant difference in the nickel concentration (Pvalue=
0.154). You have not been seen. Regarding arsenic and nickel deposits in the two
studied stations, it showed a significant difference (P<0.05), but there was no significant
difference in the concentration of cadmium (P-value=0.662). The concentration of
cadmium, arsenic and nickel in Dez river water was higher compared to the World Health
Organization standard and according to the statistical analysis of t-test, there was a
significant difference (P<0.05). Regarding the sediments, the concentration of cadmium,
arsenic and nickel was lower compared to the national environmental standard of Iran, and
a significant difference was observed between the values of these elements with the Iranian
standard (P<0.05).
Conclusion: According to the results of the studied water pollution indicators, it seems
that the Dez River has little pollution in terms of the potentially toxic elements of cadmium,
arsenic and nickel and does not have any special problems. Also, the cadmium element
enters the Dez River under the influence of human activities and causes moderate pollution
of the sediments of this river.