People who live in poverty are those exposed to the worst environmental and health risks. Overall, somewhere between 25% and 33% of the global burden of disease can be attributed to environmental factors. This proportion is larger in conditions of poverty, where more environmental hazards are present in the nearby living and working environment, and people have less capacity to protect themselves against exposure and effects of harmful or unpleasant pollutants.
Pollution and Health
The continent of Africa contains one-fifth of the world's surface and has some of the world's largest physical features, including deserts. The Sahara, which is located in the northern part of Africa, is the largest desert in the world. It also happens to be one of many deserts that are getting larger every year because of desertification.
This site contains a definition of desertification, and summarizes desertification issues in Africa.