Stress induced by soil contamination with heavy metals and their effects on some biomarkers and DNA damage in maize plants at the vicinity of Ferronikel smelter in Drenas, Kosovo.

The Ferronikel smelter in Drenas is one of the main industrial areas in the Kosovo and pollution by heavy metals causes serious threat for all living organisms on this area. The objective of this study was to determine the concentration of some heavy metals (Fe, Cu, Mn, Cr, Cd, Ni and Pb) in agricultural soils and in maize plants, and their potential toxic effects on this plant through some sensitive biochemical and molecular markers. Maize seedlings growth in nine soil samples from different locations of this area. The highest concentrations of heavy metals in soils and maize leaves were conducted close to the Ferronikel smelter, and in some locations, the nickel and chromium concertation in soils exceeded 800 mg kg-1. A significant effects of heavy metals induced toxicity resulted in the, build-up aminolevulinic acid and reduced activity of δ-aminolevulinic acid dehydratase, and chlorophyll content in the maize leaves. In general, maize seedlings growth in polluted locations showed an increase in nuclear DNA content and in G2M phase. We concluded that locations close to the smelter are affected by soil heavy metals pollution and these biochemical and molecular analysis would be a powerful ecotoxicological tool in biomonitoring of heavy metal pollution.

Risk assessment of heavy metal toxicity by sensitive biomarker δ-aminolevulinic acid dehydratase (ALA-D) for onion plants cultivated in polluted areas in Kosovo.

Biomarkers allow an integrated risk assessment of heavy metal pollution effects in living organisms. In this study, the biochemical effects of Cd, Cr, Ni, Pb and Zn pollution in agricultural soil and their accumulation in Alium cepa L. (onion) were evaluated with ALA-D enzyme response as a biomarker, along with δ-aminolevulinic acid (ALA) and total chlorophyll contents in leaves of this plant. Soil samples were randomly selected from agricultural areas in two regions, Mitrovica and Obiliqi, which are considered the most industrially polluted regions in Kosovo. Results show that Pb and Zn concentrations in soil samples from Mitrovica (1953-2576 mg kg -1) and Obiliqi regions (138-179 mg kg -1) and their bioaccumulation levels in onion were significantly higher in comparison with the control group. There was an adverse negative correlation between Pb or Zn concentration and ALA-D activity and total chlorophyll content, and a positive correlation with ALA content. This study indicates that ALA-D activity can be used as a very sensitive biomarker for evaluation of heavy metal pollution. The bioaccumulation of heavy metals from soil polluted areas poses a threat for food contamination and public health.