Effects of dumpsites air pollution on the ascorbic acid and chlorophyll contents of medicinal plants

Abstract

Deposition of air pollutants emitted from municipal solid waste on the leaves of plants growing within the vicinity of dumpsites has adverse effects on their morphological, physiological, and biochemical properties. In this study, the effects of air pollutants on the ascorbic acid and chlorophyll contents of Chromolaena odorata and Morinda lucida collected from Aba-Eku, Ajakanga, Awotan, and Lapite dumpsites, Ibadan, Nigeria, were investigated. Leaves of each plant species were separately collected and extracted with different reagents; thereafter, the ascorbic acid and chlorophyll contents of the aliquots were measured using UV/Visible spectrophotometry. Significant reductions of 13.90–61.00%; 13.85–60.43%; 13.88–60.75%; and 12.23–28.29%, respectively, occurred in the chlorophyll A, chlorophyll B, total chlorophyll, and ascorbic acid contents of the two plant species collected from the four dumpsites in comparison to the control site. The decreasing order of the percentage reduction in the ascorbic acid and chlorophyll contents of the two plant species collected at the four dumpsites is Ajakanga > Aba-Eku > Lapite > Awotan. Negative correlations revealed that reductions in chlorophyll and ascorbic acid contents of the two plant species could be attributed to deposition of air pollutants emitted from the municipal solid waste on the plants’ tissues.