Examining the Validity of EKC in Western Africa: Different Pollutants Option

Abstract

The Environmental Kuznets Curve hypothesized pollution as a monotonic function of income which implies that as an economy develops, pollution level starts to increase but reaching a certain threshold the relation reverses. This study investigates the relationship between GDP per capita income and environmental degradation in Western Africa region using panel data analysis for the period 1990-2012. Our specific objective was to estimate EKC for four indicators of environmental quality such as CO₂ emissions, Suspended particulate matter (PM10), lack of access to sanitation facilities and lack of access to safe drinking water; and establish whether these pollutants exhibit an inverted u-shape function. Likewise, we subject our estimated relationship to sensitivity checks to ensure robustness to changes in assumption and estimation techniques, an aspect inherently lacking in most EKC literature. The study could not find an unambiguous evidence of an inverted u-shaped relationship for CO₂ emissions while the other point source pollutants confirmed the EKC theory. We subjected our estimation to further robustness checks by ascertaining the statistical properties of the variables used and examined the long run sustainability; results were found to be consistent and suitable for policy inferences.