Impacts of improved traffic control measures on air quality and noise level in Benin City, Nigeria
This study has assessed the outcome of implemented traffic control measures within Benin City, Nigeria on the levels of suspended particulate matter (SPM), carbon monoxide (CO) and noise level. A positive effect of the measures was observed with a 49.4% reduction in SPM concentrations, and a decline in the baseline mean from 447.00 µg/m3 (2006) to 226.06 µg/m3 (2018). CO concentrations revealed an 89.7% reduction in the baseline concentration from an average of 19.4 ppm (2010) to 2.0 ppm (2018). This reduction was found to be statistically significant (p<0.05), however the decline in SPM concentration was not significant. Noise pollution has however remained unabated (6.41% reduction) with a baseline mean of 78.18 dB(A) in 2005 and a current average of 73.17 dB(A) (2018). The multivariate analysis conducted using Principal Component Analysis, Multiple Linear Regression and Varimax rotation, identified road traffic as the main noise source in Benin City.