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Income heterogeneity and the Environmental Kuznets Curve hypothesis in Sub-Saharan African countries

  • Muhammad Maladoh BahEmail author
  • Muhammad Mansur Abdulwakil
  • Muhammad Azam


This paper aims to empirically test the Environmental Kuznets Curve (EKC) hypothesis for ten middle income Sub-Saharan African countries over the period of 1971–2012. We observed that prior panel studies group together African countries that are heterogeneous in income levels. This study categorizes selected middle-income countries into two categories to better validate the EKC hypothesis. The study utilizes panel unit root, panel cointegration and panel dynamic ordinary least squares technique for empirical analysis. Panel cointegration results confirm the existence of a long-run relationship between environmental degradation proxied by Greenhouse gas emissions and key indicators for both middle income groups. Additionally, the long-run estimates confirm the existence of EKC hypothesis for both middle-income groups. Empirical findings suggest that it is possible for Sub-Saharan African countries to continue their efforts to spur economic growth while minimizing environmental damage at the same time.


EKC Sub-Saharan Africa Panel data 


Compliance with ethical standards

Conflict of interest

The authors declare no conflict of interest.

Human and/or animal participation

This study did not involve human and/or animal participants.


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© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Department of Economics, Faculty of Economics and ManagementUniversiti Putra MalaysiaSerdangMalaysia
  2. 2.Department of EconomicsAbdul Wali Khan UniversityMardanPakistan

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