Environmental degradation, coupled with the growth in world population, are major causes behind the rapid increase in human diseases, which the World Health Organization has recently reported. Both factors contribute to the malnourishment and disease susceptibility of 3.7 billion people, says David Pimentel, Cornell professor of ecology and agricultural sciences.
With his team of Cornell graduate students, he examined data from more than 120 published papers on the effects of population growth, malnutrition and various kinds of environmental degradation on human diseases. "We have serious environmental resource problems of water, land and energy, and these are now coming to bear on food production, malnutrition and the incidence of diseases," said Pimentel.
Nearly half the world's people are crowded into urban areas, says the report, often without adequate sanitation, and are exposed to epidemics of such diseases as measles and flu. With 1.2 billion people lacking clean water, waterborne infections account for 80 percent of all infectious diseases. Increased water pollution creates breeding grounds for malaria-carrying mosquitoes, killing 1.2 million to 2.7 million people a year, and air pollution kills about 3 million people a year. Unsanitary living conditions account for more than 5 million deaths each year, of which more than half are children.
Air pollution from smoke and various chemicals kills three million people a year. In the United States alone about 3 million tons of toxic chemicals are released into the environment - contributing to cancer, birth defects, immune system defects and many other serious health problems. Soil is contaminated by many chemicals and pathogens, which are passed on to humans through direct contact or via food and water. Increased soil erosion worldwide not only results in more soil being blown but spreading of disease microbes and various toxins.
Pimentel and his co-authors call for comprehensive and fair population policies and more conservation of environmental resources that support human life.
MEDICA.de; Source: Cornell University