The investigation of cytotoxic effects of refinery wastewater on root tip cells of Vicia faba L

Abstract

The present study was carried out to evaluate the cytotoxic effects of refinery wastewater collected from different stations of the Kizilimak river on Vicia faba L. root tip cells. For this aim, we used the gemination percentage, root length, weight gain and micronucleus (MN) frequency as indicators of cytotoxhity. Additionally to the cytological analysis, DNA analyses were performed in root tips meristems of vicia faba seeds treated with refinery wastewater. Heavy metal concentrations in the water samples were determined using atomic absorption spectrophotometer (AAS). The concentrations of heavy metals in the water were in the order of Pb>Zn>Fe>Cu>Ni>Cd>Hg. The highest germination percantage was observed in the controlgroup (in proportion as 96%). Heavy metas In the water samples collected from Statbn I, II and III caused a decrease in the germination percentage as 48,18 and 30%, respectively. The highest root length and weight gain was observed in the control group at the end of the exprimental period. The least root length and weight gain was observed in seeds treated with wastewater collected from Station I. In the control group, the weights of all tte seeds increased about 4.08 g when compared with intial weight. The root lengths of the control seeds were determined as 6.38 cm at the end of the experimerital period. The weights of the seeds exposed to wastewaters obtained from Station I, II and III increased about 1.08, 3.03 and 2.01 g according to Initial weight, respectively. Microscopic examination of V. faba root tip meristem cells showed that any example of the MN formation was not seen in the control group. The highest frequency of MN was observed in group treated with wastewater collected from Station I and least frequency of MN was observed in group treated with wastewater collected from Station II. It was also observed that the yields of DNA in the seeds exposed to wastewater were lower than recorded in the controls. Hence, DNA yields exposed to wastewater were run ahead on agarose gel according to the control group. The results clearly indicate that refinery waste water had important cylotoxic effects on V. fabe root tip cells. It was also observed that V. faba seeds are very sensitive and useful biomarkers for monitoring these effects in waters contaminated with heavy metals. © Triveni Enterprises, Lucknow (India).