The environment, which sustains human life, is also a profound source of ill
health for many of the world’s people. In the least developed countries, one
in five children do not live to see their fifth birthday – mostly because of
avoidable environmental threats to health [1]. That translates
into roughly 11 million avoidable childhood deaths each year. Hundreds of millions
of others, both children and adults, suffer ill health and disability that undermine
their quality of life and hopes for the future. These environmental health threats
– arguably the most serious environmental health threats facing the world’s
population today – stem mostly from traditional problems long since solved
in the wealthier countries, such as a lack of clean water, sanitation, adequate
housing, and protection from mosquitoes and other insect and animal disease
vectors.
Indeed:
- Contaminated water – contaminated by feces, not chemicals – remains one of the biggest killers worldwide. Lack of adequate water, sanitation, and hygiene is responsible for an estimated 7 percent of all deaths and disease globally, according to one recent estimate [2]. Diarrhea alone claims the lives of some 2.5 million children a year [3].
- Overcrowding and smoky indoor air – from burning biomass fuels for cooking or heating – contribute to acute respiratory infections that kill 4 million people a year, again, mostly children younger than age 5. The World Bank estimates that between 400 million and 700 million women and children are exposed to severe air pollution, in most instances, from cooking fires [4].
- Malaria kills 1 million to 3 million people a year [5], approximately 80 percent of them children [6]. Other mosquito-borne diseases, such as dengue and yellow fever, affect millions more each year and are on the rise, prompting the World Health Organization (WHO) to declare the mosquito “Public Enemy Number One” [7].
- Asthma is rising dramatically throughout the developed countries, and environmental factors appear to be at least partly to blame.
- Millions of people in Europe and North America are still exposed to unsafe air, and some air pollutants are proving more recalcitrant to control than many expected.
- Meanwhile, biological contamination is by no means a thing of the past, as shown by the 1993 outbreak of Cryptosporidium in the United States.
- The extension of travel and trade is providing new opportunities for the spread or re-emergence of infectious diseases. In the past two decades, some 30 “new” infectious diseases have emerged [13].




