Seasonal Variations of Heavy Metals in Atmospheric Precipitation in the Area of Sarajevo Canton

Trace metals are natural components of the environment but they have become a matter of great concern because of the continuous increase in the concentrations of these metals in our environment. Atmospheric deposition is considered a major source of toxic metals such as Hg, Cd, Pb and several others in the ecosystem. The increasing use of rainwater as an alternative household water source has led to the increased interest in the monitoring of rainwater quality. The heavy metal (Cu, Cr, Cd, Mn, Ni and Hg) in samples of atmospheric precipitation was determined in order to assess possible contamination of rainwater. The samples were collected continuously during three seasons (winter, spring and summer) in the period from December 2009 to June 2010. The sampling was conducted at two sites of the Sarajevo Canton: Bjelave (urban area) and Ivan Sedlo (rural area). The results showed that heavy metal contents (except copper and cadmium) were higher in samples from Bjelave. The results showed levels of metals in all samples as: 0.52 – 19.08 μg L-1 (Cu), 0.007 – 2.55 μg L,-1 (Ni), 0.006 – 0.26 μg L-1 (Cr), 0.02 – 3.86 μg L-1 (Cd), 0.13 – 21.59 μg L-1 (Mn) and 0.02 – 4.02 μg L-1 (Hg). The mean metal concentrations were below WHO’s limits for good quality drinking water. For most investigated metals, the highest content was obtained in precipitation sampled during spring/summer.