QUANTIFICATION OF TOXIC ELEMENTS IN TAIL HAIR OF COWS AS AN INDICATOR OF ENVIRONMENTAL EXPOSURE IN DIFFERENT AREAS FROM IRAN

This paper describes a new comparison and determination for demonstrating the levels of Al, Cd and Pb in cow’s tail hair between Tehran as a polluted area and Semnan as an area free from pollution. The hair samples were collected from a total 227 apparently healthy lactating cows above 3 years of age. This includes 165 cows reared in industrial and urban area (Tehran) and 62 cows reared in area supposed to be free from pollution (Semnan). Prior to analysis, samples were washed with 0.1M HCl, acetone and deionized water. The hair samples were digested afterward in a mixture of nitric and perchloric acid mixture (HNO3:HCLO4=4:1 v/v). Concentrations of all metals were assessed by flame and graphite furnace atomic absorption spectrophotometer.