Abstract
Water toxicity originating from the atmospheric deposition of six heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) was investigated on Vibrio fischeri activity in Izmir, Turkey. A LUMIStox® test was applied to dry and wet deposition samples and metal solutions. The inhibition levels and effective toxicity concentrations of these samples and solutions were determined. Interactive toxicity effects among the metals were investigated. When the impacts of the synthetic single heavy metal solutions were compared with each other, a toxicity ranking of Cr>Cd>Pb>Cu>Zn>Ni was obtained in order of decreasing severity. The total effective concentrations of these six metals were in the ranges of 0.074–0.221 mg/L and 0.071–0.225 mg/L for receiving aqueous solutions of dry and wet atmospheric depositions, respectively. The toxicity data showed that the wet deposition samples were 15% more toxic than the dry deposition samples. The interactive toxicity effects of the heavy metals in both dry and wet deposition samples were classified as antagonistic. High levels of heavy metals deposited in dissolved form may constitute an important input in the biochemical cycle and may have significant impacts.
Acknowledgments
The Dokuz Eylul University Research Funds and TUBITAK 100Y104 project are acknowledged for their partial financial support. The authors are thankful for the analytical help of Dr. Umit Divrikli from Pamukkale University Chemistry Department and the encouraging comments of Dr. Mustafa Odabasi (Dokuz Eylul University) and Dr. Emur Henden (Ege University). The Dokuz Eylul University Air Pollution Laboratory staff and Dr. Neval Baycan Parilti, who helped initiate the experiments, are gratefully acknowledged as well.