This study investigates the validity of the Environmental Kuznets Curve (EKC) hypothesis for six West African countries over 1970-2017 while using human capital and biocapacity as additional determinants of carbon emissions. It uses the panel quantile regression method that provides robust results in case the classical econometric assumptions fail. The empirical results revealed that a U-shaped relationship between economic growth and Carbon dioxide (CO₂) emissions holds in the low, middle and high-emissions countries as opposed to the inverted U-shaped EKC hypothesis. Trade openness reduces environmental performance in low-emission countries. Financial development has mixed impacts on CO₂ emissions across the quantiles. While financial development enhances environmental quality in the low-emissions countries, it exerts a detrimental impact in the middle and high-emissions countries. Human capital has significantly positive effects on the lower, middle and upper quantiles. The obtained results highlight the need for raising environmental awareness and promoting green R&D. In addition, relevant incentives are required to redirect private credits towards green projects and renewable energy development.

这项研究调查了六个西非国家在1970-2017年间环境库兹涅茨曲线（EKC）假设的有效性，同时使用人力资本和生物承载力作为碳排放的附加决定因素。它使用面板分位数回归方法，可以在经典计量经济学假设失败的情况下提供可靠的结果。实证结果表明，在低排放，中排放和高排放国家，经济增长与二氧化碳（CO ₂）排放之间存在U型关系，这与倒U型EKC假设相反。贸易开放降低了低排放国家的环境绩效。金融发展对CO _2的影响喜忧参半跨分位数的排放。金融发展提高了低排放国家的环境质量，但对中高排放国家却产生了不利影响。人力资本对较低，中等和较高分位数具有明显的积极影响。获得的结果突出了提高环境意识和促进绿色研发的需要。此外，还需要采取相关激励措施，将私人信贷转向绿色项目和可再生能源开发。