Water bodies near urban areas are generally the most severely polluted, and the situation is deteriorating. Many urban sections of rivers are polluted by toxic and even carcinogenic compounds, such as arsenic. Although most Chinese attempt to protect themselves from bad water by boiling it, boiling does not affect many of the toxins.
Biological contamination remains a problem as well. Indeed, fecal coliform, mostly from sewage, has become the most challenging drinking water pollutant in the country. In 1994, 54 out of 134 rivers tested did not meet Grade 4 and 5 surface water standards, indicating that the water was deemed unsuitable for even industrial or agricultural use. About 90 percent of the sections of rivers around urban areas were found to be seriously polluted. Because heavy industry is concentrated in northern China, the major river systems in the North are more heavily polluted than those in the South [66]. (See Polluted Rivers.)
Health Implications
Access to safe drinking water is key to protecting public health
The health of China’s people depends, to a great extent, on the quantity and quality of its drinking water supply. Drinking water quality is largely determined by sources of incoming water, modes of water supply, and the level of water treatment. The majority of Chinese urban and some suburban residents now have access to tap water, while the largest portion of the rural population still relies on hand- or motor-pumped wells, or they fetch water directly from rivers, lakes, ponds, or wells, with little or no treatment at all. Large rivers are the most common source of urban drinking water, as well as the major source for rural residents in many parts of the country.
In only 6 of China’s 27 largest cities does drinking water quality meet state standards, according to one recent study. Groundwater did not meet state standards in 23 of these cities [67]. The problem is more pronounced in rural China. In some rural areas, the fecal coliform in the drinking water supply exceeds the maximum level by as much as 86 percent; in towns and small cities, the rate is about 28 percent. Currently, around 700 million people in China drink water that fails to meet state standards for fecal coliform [68].
Over the past decade, the government has launched a major initiative to improve access to safe drinking water in rural areas. From 1991 to 1995, the government spent 14.45 billion yuan (US$1.35 billion) to improve the drinking water supply in rural regions [69]. Although the rural population with access to tap water more than doubled between 1987 and 1995, when it reached 47 percent, more than one half of those people still drank water that failed to meet safety standards [70].
Infectious diseases associated with poor water quality
Despite an overall decline in mortality from infectious diseases in China, the population still suffers from a number of diseases associated with inadequate drinking water quality and sanitation. For the past two decades, diarrheal diseases and viral hepatitis, both diseases associated with fecal pollution, have been the two leading infectious diseases in China. In 1995, the incidence of hepatitis was 63 per 100,000, a 46 percent decrease from 1991. After a sharp drop from 1991 and 1992, the incidence of dysentery has risen since 1994, in part because of the deterioration of water quality. A sudden upswing in the incidence of typhoid fever in 1991 and a large outbreak in some provinces in 1992 were also partly attributed to the poor drinking water quality in rural areas. In 1991, typhoid fever incidence reached as high as 10.6 per 100,000. Although the incidence of waterborne diseases is still high compared with many other countries, effective medical care has kept mortality low, averaging less than 0.1 per 100,000 [71].
It is more difficult to establish the impacts of industrial and chemical water pollution on human health than pollution by human waste. However, recent epidemiological studies suggest that exposure to organic and inorganic chemicals in drinking water may significantly contribute to chronic disease. Liver and stomach cancers are the leading causes of cancer mortality in rural China. Many studies in China and abroad have shown a strong association between drinking water pollution and cancer incidence and mortality. An example is a study conducted in Lujiang County, Anhui Province, where mortality rates for stomach and liver cancers were associated with the high levels of inorganic substances in surface water [72]. Although diet and alcohol consumption may play some role in the increases of these cancers, environmental causes cannot be dismissed [73]. Since the 1970s, deaths from liver cancer have doubled – China now has the highest liver cancer death rate in the world [74].
In southern China, where some of the population has long depended on ponds for drinking water, the rates of digestive-system cancers are very high. An investigation of 560,000 people in 23 villages and towns showed that between 1987 and 1989, cancer mortality was 172 per 100,000, which is much greater than the average mortality rates in rural China [75]. Gastric, esophageal, and liver cancers accounted for 85 percent of all cancers. Other studies reported that the high incidence of liver cancer in Jiangsu’s Qidong and Guangxi’s Fushun regions is highly correlated with drinking water pollution [76] [77]. Further research is needed to confirm this link and identify the specific pollutants at fault.
References and notes
66. Op. cit. 10.
67. Vaclav Smil, Environmental Problems in China: Estimates of Economic Costs, East-West Center Special Report No. 5 (East-West Center, Honolulu, 1996), pp. 2, 24.
68. Cai Shiwen, “China’s Environmental Pollution and Health Problem,” paper presented at the Second Conference of the China Council of International Cooperation and Development, Beijing, 1993.
69. China Ministry of Public Health, China Yearbook of Public Health 1996 (People’s Medical Publishing House, Beijing, 1997), pp. 416<196>417.
70. Zhang Feng et al., “Status and Analysis of Rural Drinking Water Quality,” Journal of Hygiene Research, Vol. 26, No. 1 (1997), pp. 30<196>32.
71. China Ministry of Public Health, Selected Edition on Health Statistics of China, 1991<196>95 (China Ministry of Public Health, Beijing, 1996), pp. 69<196>70.
72. Guili Chen, “The Warning of Huai River,” Contemporary Magazine, Vol. 2 (1996).
73. Howard Frumpkin, “Cancer of the Liver and Gastrointestinal Tract,” in Textbook of Clinical Occupational and Environmental Medicine (W.B. Saunders Co., Philadelphia, 1994), p. 576.
74. Feng Rukang, “China Maps Out Geographical Belt of Liver Cancer,” China Environment News (October 15, 1997), p. 8.
75. Su Delong, “Drinking Water and Liver Cancer,” Journal of Chinese Preventative Medicine, Vol. 14, No. 2 (1990), pp. 65<196>73.
76. Liang et al., “Epidemiologic Investigation of Relationships Between Drinking Water Types and Liver Cancer,” Cancers, Vol. 6, No. 3 (1987), p. 177 (in Chinese).
77. Tang He and Lin Nianfeng, “The Relationship Between Organic Water Pollution and Liver Cancer at Fushui in Guangxi,” Journal of Environment and Health, Vol. 12, No. 5 (1995), pp. 193<196>195 (in Chinese).
