Smoke from indoor cooking fires that burn fuelwood and dung is estimated to cause the death of 4 million children each year worldwide. Lack of sanitary conditions contributes each year to approximately 2 billion diarrhea infections and 4 million deaths, mostly among infants and young children in developing countries. In the United States, inadequate sanitation accounts for 940,000 diarrhea infections and about 900 deaths each year. Dengue fever, spread by mosquitoes that breed in old tires and other water-holding junk in crowded urban environments, infects an additional 30 million to 60 million people each year. Less than one percent of 500 Chinese cities have clean air.
Respiratory disease is the leading cause of death in China.
In China, where tobacco smoking increased from approximately 360 to nearly 1,800 cigarettes per person per year, males smoke 98 percent of the cigarettes. However, mortality due to lung cancer is approximately equal in males and females. Although the use of lead in U.S. gasoline declined since 1985, other sources inject about 2 billion kilograms of lead into the atmosphere in this country each year. An estimated 1.7 million children in the United States have unacceptably high levels of lead in their blood. Production of another gasoline component, the carcinogen benzene that causes leukemia even at low dosages, rose from 0.5 billion kilograms in the United States in 1950 to current levels of about 7.5 kilograms per year.