relationship between lead (pb) concentration in soil, grass ,blood, milk and δ-aminolevulinic acid dehydratase (alad) activity , hemoglobin (hb) and hematocrit (hct) in grazing cows from vicinity of smelter “trepça” in kosovo

This study aimed to evaluate current lead concentration (pb) in topsoil, grass, blood and milk, alad activity, hemoglobin (hb) and hematocrit (hct) i cows (simmental breed), rearing in three villages situated in different distances from the smelter “trepça”: kalemend 2km, boletin 3km and zazhë 5km and koliq 40km. the pb concentration in samples is measured by atomic absorption spectrometry ( aas), blood alad activity is measured according the cec standardized method. pb concentration in topsoil and grass in the three villages from smelter is higher (p<0.001) than pb concentration in reference. blood lead level (bll) in cows from smelter area is higher (p<0.001) than in control. milk lead level (mll) in cows from smelter area is higher compared with control. blood alad activity in cows from smelter area is significantly (p<0.001) inhibited compared with control. there is adverse correlation (r=-0.812, p<0.001) between bll and alad activity in cows from kelmend, a positive correlation ((r=0.987, p<0.001) is established between bll and mll in cows from boletin. there is no significant difference of hb and hct values among each group of cows. there was progressive decrease of pb concentration in topsoil, grass, blood and milk with increasing distance from the smelter. alad activity is proved as sensitive and useful biomarker at very low blls in cows. the vicinity of smelter still poses threat for livestock welfare and human health.