42
long- range transport of the pollutants. The disparity on the distribution of the concentration data indicates that the data are affected by several factors. The concentration data onto Hg are characterized by moderate variation and look likely more stable.
2.3.2 Spatial Distribution of As, Cd, Cr, Co, Cu, Hg, Pb,
Ni and Zn
The study of As, Cd, Hg, Pb and Ni in moss samples of this study followed the
European Air Quality Directives 2004/107/EC and 2008/50/EC that only demand
these elements as the most toxic (de Nicola et al. 2013). As the emissions of heavy
metals were considerably decreased in the Europe (Harmens et al. 2015) and EMEP
region (Ilyin et al. 2013) over the last two decades, there are still evident the exceedances of critical loads for Hg across nearly 90% or more of ecosystem area of
Balkan area, Denmark, Italy, Latvia, Lithuania, Luxembourg, the Netherlands,
Poland and Spain (EEA 2013). Beside the exposure to the high ambient air concentrations, higher than the limit or target values of ambient air concentrations above
the limit or target values is a local problem in a few areas in Europe (Harmens et al.
2015, EEA 2013). The content of metals in the air is strongly linked with the content
of PM. The PM2.5 emissions were reduced mostly in Europe as a consequence of
improving technologies, but the Balkan countries, like Albania, Bosnia and
Herzegovina, Montenegro, North Macedonia and Serbia, as well as Iceland, Norway
and Switzerland did not show a significant reduction between 1990 and 2013
(Colette et al. 2016). The spatial distribution and the factors affecting the emission
of As, Cd, Hg, Pb and Ni in Albania are discussed. The elements As, Cd, Hg, Pb and
Ni are released into the atmosphere from both natural and anthropogenic sources.
The main anthropogenic sources include metal smelters and fuel combustion, traffic, waste incineration, windblown soil dust and mining industry. The main natural
sources of Hg emissions are diffusion from the earth’s mantle through the lithosphere, evaporation from the sea surface and geothermal activity (EEA 2013).
2.3.2.1 Arsenic
Arsenic concentrations show high differences in moss samples (CV% = 91% > 75%).
The concentration data were followed by high values of skewness and kurtosis (2.7
and 8.6, respectively) indicating a high disparity in its distribution pattern throughout the country. It is probably derived from the local emission sources and longrange atmospheric transport. As content in moss samples ranged from 0.13 to
3.18 mg kg
−1
with an average content of 0.62 mg kg
−1
, higher than the As concentration range founded in 2010 AMS (0.5–2.86 mg kg
−1
and the average content of
0.48 mg kg
−1
). To distinguish the contributions from the natural and anthropogenic
sources, the concentration data of As are normalized by using Li as a typical
S. Allajbeu et al.
long- range transport of the pollutants. The disparity on the distribution of the concentration data indicates that the data are affected by several factors. The concentration data onto Hg are characterized by moderate variation and look likely more stable.
2.3.2 Spatial Distribution of As, Cd, Cr, Co, Cu, Hg, Pb,
Ni and Zn
The study of As, Cd, Hg, Pb and Ni in moss samples of this study followed the
European Air Quality Directives 2004/107/EC and 2008/50/EC that only demand
these elements as the most toxic (de Nicola et al. 2013). As the emissions of heavy
metals were considerably decreased in the Europe (Harmens et al. 2015) and EMEP
region (Ilyin et al. 2013) over the last two decades, there are still evident the exceedances of critical loads for Hg across nearly 90% or more of ecosystem area of
Balkan area, Denmark, Italy, Latvia, Lithuania, Luxembourg, the Netherlands,
Poland and Spain (EEA 2013). Beside the exposure to the high ambient air concentrations, higher than the limit or target values of ambient air concentrations above
the limit or target values is a local problem in a few areas in Europe (Harmens et al.
2015, EEA 2013). The content of metals in the air is strongly linked with the content
of PM. The PM2.5 emissions were reduced mostly in Europe as a consequence of
improving technologies, but the Balkan countries, like Albania, Bosnia and
Herzegovina, Montenegro, North Macedonia and Serbia, as well as Iceland, Norway
and Switzerland did not show a significant reduction between 1990 and 2013
(Colette et al. 2016). The spatial distribution and the factors affecting the emission
of As, Cd, Hg, Pb and Ni in Albania are discussed. The elements As, Cd, Hg, Pb and
Ni are released into the atmosphere from both natural and anthropogenic sources.
The main anthropogenic sources include metal smelters and fuel combustion, traffic, waste incineration, windblown soil dust and mining industry. The main natural
sources of Hg emissions are diffusion from the earth’s mantle through the lithosphere, evaporation from the sea surface and geothermal activity (EEA 2013).
2.3.2.1 Arsenic
Arsenic concentrations show high differences in moss samples (CV% = 91% > 75%).
The concentration data were followed by high values of skewness and kurtosis (2.7
and 8.6, respectively) indicating a high disparity in its distribution pattern throughout the country. It is probably derived from the local emission sources and longrange atmospheric transport. As content in moss samples ranged from 0.13 to
3.18 mg kg
−1
with an average content of 0.62 mg kg
−1
, higher than the As concentration range founded in 2010 AMS (0.5–2.86 mg kg
−1
and the average content of
0.48 mg kg
−1
). To distinguish the contributions from the natural and anthropogenic
sources, the concentration data of As are normalized by using Li as a typical
S. Allajbeu et al.