Vehicular emissions have emerged as one of the major sources of air pollution in urban centers. The increasing intensity of road traffic congestions as a result of many vehicles is a serious threat in Port Harcourt environment. Also, a plan by the Rivers State Government to extend the city Centre to Etche Local Government is a major concern. This study analyzed the concentrations of carbon monoxide, Nitrogen dioxide and sulphur dioxide respectively, in both Port Harcourt (urban milieu) and Etche (Rural Milieu). A simple random, sampling technique was adopted in selecting the sample locations in both milieus. From the analysis, carbon monoxide gave the highest concentration in the two peak periods (morning and evening), and for both milieus; sulphur dioxide was found to have the lowest concentration, for both Port Harcourt and Etche. Statistical package for social science (SPSS version 17.0) was used, and the statistical tools adopted in analyzing the three research hypothesis formulated were Analysis of variance (ANOVA), and Regression analysis. Findings, indicated that a significant difference exist between the concentration of pollutant in Port Harcourt, and Etche Areas. Secondly; the air pollution is higher during the peak periods in Port Harcourt Environment, and the meteorological parameters considered, significantly influence pollutant dispersion in both milieus. The analysis Shows that the urban milieu are more polluted than rural milieu, and that traffic congestion in Port Harcourt city is a serious threat to traffic wardens, and road side business operators.
