Abstract

• The research work intend to study the heavy metal contamination, originating from motor vehicle traffic in roadside soils near the Kali-Tollgate and Bayintnaung- Quarter on the highway road of Bago to Mawlamyine. Twenty one soil samples were collected from (Kali-Tollgate) according to the distances. Five soil samples were collected from Bayintnaung-Quarter according to the depth profile. Semi-quantitative analyses of the soil samples were done using EDXRF technique. Atomic absorption spectrophotometric method was used for the determinations of heavy metals in soil samples. Changes of concentrations of heavy metals (Pb, Zn, Cu and Cd) with distance from the highway road were studied by using single exponential decay model equation. The data were compared with maximum allowable limit of soil of highway road. The Lead content of the roadside soil range from 12.1 to 102.5 ppm, the Zinc content of the roadside soil range from 8.8 to 206.5 ppm, the copper content of the roadside soil range from 14.1 to 111.5 ppm and the cadmium content of the roadside soil range from 1.3 to 7.9 ppm according to the distance. In general heavy metal concentration decreased with increased distance from the highway road. In all soil samples measured according to the depth profile, Zn concentration was highest, whereas Cd concentration was lowest. In the depth profile of 0.5, 20- 30 cm, Pb concentration were in the range of 55.10 ppm to 20 ppm, Zn concentration were in the range of 264.20 to 56.60 ppm ,Cu concentrations were in the range of 48.0 ppm to 9.2 ppm, Cd concentrations were in the range of 2.1 ppm 1.3ppm. The maximum heavy metal concentration was observed at 0-5 cm depth and the concentration decreased with an increase. The data obtained that measured according to the distances except Cd, were within the maximum allowable limit. They slowly find entry into food chain leading to serious health hazards. Therefore, there is an urgent need for policy regulations to minimize indiscriminate disposal of oil contaminated residues, vehicular emissions, road transport and traffic emissions and the wear and tear of mechanical parts in vehicles beside.