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Oct 18, 2015 - Belinda Hoxha , Marilda Osmani, Frederik Cane , Piro Karamelo , Nikolin Gega ... times higher than several international stan- dards, and thus ...

6th INTERNATIONAL SYMPOZIUM OF ECOLOGISTS OF MONTENEGRO, ISEM6 Montenegro, Ulcinj, 15-18 October 2015 COMPARATIVE STUDY ON HEAVY METAL POLLUTION IN SOIL IN ELBASAN REGION Belinda Hoxha , Marilda Osmani, Frederik Cane , Piro Karamelo , Nikolin Gega “Aleksander Xhuvani” University, Faculty of Natural Sciences, Department of Chemistry, Elbasan, Albania

INTRODUCTION Industrial activity is among the primary sources of pollution which contribute to heavy metal pollution (Alloway 1995a). These elements are essential to plants and humans, but when they are added or emitted in high quantity they might have adverse effects on the ecosystem and human health. Soil, as the final recipient of these metals might be considered as the most difficult to evaluate, because it is a very complex media and a great number of chemical processes take place there (Fergusson 1991). Heavy metal pollution in industrial areas worldwide is becoming a real concern nowadays, because of its risk for humans and ecosystems. The same situation is becoming obvious in Albania, especially in areas, which have had an intensive industrial activity and are regarded as environmental “hot spots”. The concentrations of chromium, nickel, cobalt, copper and lead, which are regarded as hazardous in high quantities (Malachowski 1995) are found in quite high amounts in soils around these areas (UNEP 2000a). The majority of these industrial plants are partly or completely abandoned after years of operation (MoE 2002; REC 2000) without any environmental provision. Ebasan is considered one of these “hot spots” in Albania, because of the metallurgical activity (UNEP 2000a; UNEP 2000b) taking place there since 1976. Therefore, it has been contributing to air, water and soil pollution. The focus of this study is to show the variation of heavy metal concentrations in soil around the industrial area of Elbasan region through the years. In order to accomplish the above goal, the concentrations in cultivated soil of heavy elements such as chromium, nickel, cobalt, copper and lead, which are regarded hazardous in high quantities, are reviewed in the paper, with major focus on chromium and nickel levels.

MATERIALS AND METHOD This paper has considered several studies, which focused on heavy metal pollution of Elbasan region. There are no/less data before the 1990s about environmental issues in general and on heavy metal pollution in particular. The earliest documented study on heavy metal pollution dates on 1996 (Lausmann 1996), time when most factories of the metallurgical plant were closed and abandoned. Therefore, the Laussmann’s (1996) study represents the soil contamination after many years of operation of this industrial plant. Later on, environmental issues in this area received special attention among researchers, particularly when part of the plant became inhabited.

Concentrations of heavy elements in cultivated soil from these studies (Lausmann 1996; Lushaj et al 2001; Hoxha 2005; Osmani and Bani 2014) are compared with international standards in order to give the general view of heavy metal tendency through the years. One must consider the fact that this paper compares the average values of heavy metal in soil. However, their concentrations in different sampling points in each case differ.

RESULTS Cultivated/agricultural soils are of special importance regarding heavy metals in soil, because of the present risk of their passage from soil to plant and humans afterwards. Chromium and nickel are of major concern in cultivated soils in Elbasan industrial area. Furthermore, their concentrations in soil are found several times higher than several international standards, and thus representing a continuous hazard for the ecosystem and human health.

CONCLUSIONS Considering the above research studies, it can be concluded that: - Heavy metal concentrations in soil, particularly in cultivated soils are high enough to pose serious hazard to the ecosystem and human health. - High concentrations are due to the past/ present industrial activity in the metallurgical plant area. - Chromium and nickel appear to be the most problematic elements in cultivated soil with the high concentrations in each research compared with international standards. - Further studies could establish the most effective method of cultivated land restoration, including the hipperaccumulative plants.

References

Chromium and nickel concentration averages are higher than the respectively background levels of 349 and 294 ppm (Shtiza et al. 2003). Moreover, the measured values are higher than the desirable maximum level of chromium and nickel in unpolluted soil (100 and 35 ppm) (WHO 1996). The UK list for gardens determines concentration of chromium and nickel of 25 μg/g and 70 μg/g (Alloway 1992). When considering these values, it should be clear that these limits imply their threshold for cultivated soils. As it can be seen in table 1, chromium and nickel are several times higher in each study than their threshold determined in UK list (Alloway 1992). Chromium and nickel concentrations are respectively 4-7 times and 6-10 times higher than the threshold for the contaminated soils (ANZ 1982). Similar situation can be noted if the figures are compared with the Dutch list (Mazreku 2005).

Alloway. B. J. 1992. Land contamination and reclamation. In Understanding our Environment: An Introduction to Environmental Chemistry and Pollution, ed. R.M Harrison, 137-164 Cambridge: The Royal Society of Chemistry. Hoxha, B. 2005. Heavy metal pollution in industrial areas in Elbasan, Albania, Master of Science thesis, Department of Environmental Sciences and Policy, Central European University, Budapest Lausmann, M. 1996. Das Unweltpilotprojekt Elbasan, Albanien. (Environmental project pilot Elbasan, Albania). Research study, Germany. Lushaj, Sh., Laze, P., Belalla, S., Kovaci, V., Feta, Dh. and Zonja, Zh. 2001. Monitorimi i ndotjes se tokave bujqesore dhe erozionit (Pollution and erosion monitoring of agricultural soils). Buletini i Shkencave Bujqesore, 2: 25-36 Shtiza, A, Swennen. R and Tashko.A. 2003. Importance of the geological substrate in environmental studies: a case study from pollution around chromium smelters in Albania. Unpublished paper presented in the International Symposium on Eastern Mediterranean Geology. Selanik, Proceedings 1026-1029 Mazreku, A. 2005. Impakti Ambjental i Industrise se Metalurgjise se Zeze ne rajonin e Elbasanit (Environmental Impact of Black Metallurgy in Elbasan region). Thesis submitted at Department of Geology Polytechnic University, Tirana, Albania. Osmani, M. and Bani, A. 2014. Phytoextraction of heavy metals in the metallurgical area soils (Elbasan). Proceedings of International Conference “Green Energy and Environmental Science”, Tirana 1-2 December 2014

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