Growth Thresholds and Environmental Degradation in Sub-Saharan African Countries: An Exploration of Kuznets Hypothesis

Document Type: Original Research


1 Department of Economics, Al-Hikmah University, Ilorin, Nigeria

2 School of Economics, Universiti Kebangsaan Malaysia (UKM), Malaysia


This study investigates the presence of environmental Kuznets curve (non-linear relationship between pollution and the per capita income) in Nigeria, Ghana, Cote d’Ivoire, Mali and Senegal and Gabon. In the study, pollution is regressed on per capita income, squared per capita income, trade intensity, foreign direct investment and population density price. Panel estimation technique and ordinary least square were used to obtain required estimates for all selected countries and individual economies. The study established the presence of environmental Kuznets curve for these countries at group and individual level. It also revealed that the value of turning point in pollution level corresponding to per capita income is varying among countries. From the result, the threshold GDP per capita (constant 2005 US$) is approximately $758 for Nigeria, $7060 for Gabon, $585 for Ghana, $1014 for Cote d’Ivoire, $390 for Mali and  $675 for Senegal. The declining trend of pollution with regards per capita income could be attributed to introduction of environmental friendly products, structural changes in the industrial sector of these countries that involve more output per primary resources.


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