Biomonitoring of air pollution with mercury in Croatia by using moss species and CV-AAS

Moss samples from four dominant species (Hypnum cupressiforme, Pleurozium schreberi, Homalothecium sericeum and Brachythecium rutabulum) were collected during the summer and autumn of 2010 from 121 sampling sites evenly distributed over the territory of Croatia. Samples were totally digested by using microwave digestion system, whilst mercury was analysed by using cold vapour atomic absorption spectrometry (CV-AAS). Descriptive statistics were done from analyses of mercury in all moss samples. The content of mercury ranged from 0.010 to 0.145 mg kg−1 with a median value of 0.043 mg kg−1. Hg distribution map shows the sites of the country with higher levels of this element. High contents of Hg were found in moss samples collected from the regions of Podravina and Istria as a result of anthropogenic pollution. Comparison of median values and ranges with those found in moss samples in 2006 shows slight reduction of mercury air pollution. When compared to the results obtained from recent studies conducted in Slovenia, Macedonia and especially in Norway—which serves as a reference considering the fact that it is a pristine area—mercury air pollution in Croatia is insignificant.