Distribution of metals in urban street dusts of Benin City,Nigeria

Dust samples were collected from 30 sites within benin city,nigeria,during the month of december,2006 - march 2007 and analysed for cu,cr,ni,cd and pb using atomic absorption spectrophotometry. the samples were divided into 3 categories,including a control. results showed that the dust samples contained significant levels of the metals studied compared to the control site. the mean values for cu,cr,ni,cd and pb were 16.83 mg/kg,55.40 mg/kg,5.91 mg/kg,3.17 mg/kg,and medium traffic areas,while mean concentrations of cu,cr,ni,cd and pb in the low traffic areas were 10.46 mg/kg,58.7 mg/kg,8.06 mg/kg,3.49 mg/kg and 142.53 mg/kg,respectively. these values suggest that motor vehicles and electricity generating sets formed the major sources of these metals in the dust samples. the values of metals in the dust samples in these areas were compared with the results of investigations in other countries and these values at various zones of benin city were found similar,which indicates that benin city can be considered as one big urban centre with high population and traffic density.