Environmental problems behind the Great Wall.

China is a rapidly developing country with one-fifth of the world's population. The country faces major social and political problems, which have gained the world's attention. Equally challenging are serious environmental problems resulting from overpopulation, rapid industrialization, and overuse of natural resources that could potentially threaten the health of China's 1.2 billion people, whether they live in cities or the rural countryside. The most serious environmental health problem, say Chinese environmental health experts, is air pollution. One example is Taiyuan, the capital of Shanxi Province and an ancient fortified city located in a valley. Iron, steel, and chemical factories spew soot, fly ash, and sulfur dioxide into the air, and the pollutants are trapped within the valley and the walls of the city, according to the Chinese National Environmental Protection Agency (NEPA). Two million people live in Taiyuan. Indoor air pollution is also a serious threat. Women in rural Xuan Wei County of Yunnan Province have the highest lung cancer rate among Chinese women, even though few smoke. The greatest cancer risk is among residents who burn smoky coal inside their homes with no ventilation. The Chinese Academy of Preventive Medicine says thousands of Chinese in other rural areas suffer debilitating diseases from burning coal containing arsenic and fluoride. Most factories built before the 1980s have no pollution control equipment and are fueled by coal, which the government calls "the chief source of air pollution in China." According to Vaclav Smil, professor and author of China 's Environmental Crisis, "Burdens of air pollution are not surprising in a nation where combustion of one billion tons of coal, largely uncleaned and burned with minimal or no pollution controls, supplies three-quarters of all primary energy." As a result, numerous cities in China exceed World Health Organization air pollution guidelines. Statistics show high morbidity and mortality from lung disease in China. Respiratory disease is one of the leading causes of death overall in China. It is the primary cause of death among rural residents , who have a mortality rate of 168 per 100,000 people. Cancer is the primary cause of death among urban residents, who have a mortality rate of 126 per 100,000 according to the 1992 Report on the State of the Environment in China, published by NEPA. "Environmental pollution and unhealthy habits are the main causes of disease ," the report concludes. "Unhealthy habits" include smoking-a habit shared by 300 …