Abstract

Awotoye, O.O.

Plastic shopping bags are widely used for transporting a range of small consumer goods, and in some regions, also serve secondary roles for conveying drinking water1 and disposing of human and other domestic wastes2 . While annual production and use statistics are not available from industry sectors, environmental groups estimate that between 500 billion and 1 trillion plastic bags are used globally each year3 . Since their inception, uncontrolled disposal of these bags has been causing environmental problems worldwide, and many municipal, regional, and national governments are beginning to take action. The problem is particularly acute in Africa due to its unique set of socio-economic and political conditions. Similarly unique solutions will be needed to solve this complex issue. In a number of African countries, plastic bag pollution is causing severe environmental and health damage that manifests itself in a number of ways (Figure 1). The bags are also used for disposing of human waste in city streets, in gutters, and on neighbouring roofs. This leads to an "out-of-sight, out-of-mind" philosophy that superficially and incorrectly portrays the absence of the existing health risks compared to otherwise "open" human waste disposal. Bags can block storm drains and sewage systems, leading to flooding and increased spread of disease. Water trapped in the bags also provides an ideal breeding ground for mosquitoes, raising the risk of malaria transmission4 . Since most landfills are not routinely covered with soil in Africa, the bags are easily transported around the countryside where wildlife and livestock consume the materials5 . Numerous cases of animal injury and death as a result of this practice have been reported. Where the bags are burned either for energy or mass reduction purposes, heavy metals and toxic organic compounds (e.g., polychlorinated dibenzo-p-dioxins and furans [PCDD/Fs; commonly referred to as "dioxins"] and polyaromatic hydrocarbons [PAHs]) can be produced. In agricultural areas, the bags can interfere with water and air movement through the soils, and thus decrease productivity of much-needed farmlands2 . And perhaps of greatest consequence, regardless of their location or end use, the bags require unsustainable petroleum-based raw material inputs for their production and once produced require centuries or millennia to decompose.