Atmosferik çökelmenin ekotoksisitesi

Dry and wet deposition samples were collected between October 2003 and June 2004 inBuca, Izmir. Dry and wet depositions of selected heavy metals (Cr, Cd, Pb, Cu, Zn and Ni)were measured using a water surface sampler (WSS).Dry and wet deposition samples were filtered and both filters and filtrates were analyzedfor selected heavy metals using atomic absorption spectrometry with graphite furnaceexcept for zinc which was analyzed by using a flame technique.Wet deposition rates are found to be more significant than the dry deposition rates on dailybasis except Ni. However, dry deposition plays more important than that of wet depositionthroughout the study period in this suburban area.LUMIStox toxicity test working with Vibrio fisheri populations was used to determine theoverall toxicity of the collected deposition samples. Toxicity evaluations are based onsoluble fractions of the studied heavy metals. Toxicity ranking of metals from most toxicto least toxic in this study was found as Cr, Cd, Pb, Cu, Zn and Ni. Good agreement wasfound for studied heavy metals between our results and most of the reported work of othersexcept chromium toxicity level.Rainwater samples were found more toxic than dry deposition samples. The studied metalsare ready to impose ecotoxic impacts in the water-soil environments and on biota inrelation to the soluble fraction ratios in deposition in Izmir.