Occupational epidemiology in China comes of age

EDITORIAL Occupational

Epidemiology

in China

The report by Qiao and colleagues (l), in this issue of the Annals ofEpi&mioloa, extends our knowledge of risk factors for lung cancer in a high-risk occupationally-exposed population. The authors have found that within a large group of occupationally exposed tin miners, radon and arsenic are predominant risk factors for lung cancer, and that silica exposure (as silicosis and as total dust exposure) remains significant even in a population heavily exposed to other carcinogenic activities. They also document the expected close association with tobacco usage, thereby confirming what has undoubtedly become China’s leading nonoccupational risk factor for disease among workers, and note that the presence of a chronic inflammatory condition, chronic bronchitis, predicts risk for lung cancer. These findings do more than confirm previous observations on all these associations. They place these observations in a context, comprehensible in a complicated real world of hazardous work and lifestyle characteristics, where a great number of workers actually live, in a society with one-fifth the world’s workers. This is an important contribution for the protection of a large group of workers in China who face these risks. Scientifically, the paper is a valuable contribution to understanding the attributable risk associated with various exposures in a setting characterized by numerous occupational hazards. This study from Yunnan complements studies of other similar settings such as the Dachang tin mine in Guangxi province (2). Comparing the findings from each provides a framework for interpretation that can be used in toxicologically-oriented investigation (3) and on a practical basis in regulatory applications and risk assessment (4). Studies such as this mark a coming of age for occupational health research in the People’s Republic of China. The steady flow of good research coming out of China today reflects a historical triumph of scientific inquiry over adversity (4, 5). From the time of “Liberation” (1949) until well into the economic expansion, following the reforms introduced by Deng Xiaoping in 1978, China struggled mostly alone and in isolation. Except for some Soviet help in the early years, withdrawn in the 196Os, China tried on the basis of a rigidly ideological scheme to modernize industry and to protect the workers that were the proletarian basis of a Marxist state. Serious mistakes were made that wrenched society and the economy. These were reflected in unacceptable rates of occupa-

Ann Epidemiol 1997;7:530-532 0 1997 Elsevier ScrenceInc. All rights reserved. 655 Avenue of the Americas, New York, NY 10010

Comes of Age tional injuries and disease, rates which seemed to be sensitive indicators of economic and social confusion. Most of these data have not been published and no doubt accurate data will never be available for some periods of China’s recent history. Throughout its setbacks, however, China maintained an ideological commitment to its citizens to provide primary health care, and to its workers, the proletariat (how dated this vocabulary sounds!), as well as provide periodic health evaluation, treatment, and rehabilitation to injured workers in a network of specialized centers for research, evaluation, and treatment of occupational diseases (4-7). Although prevention was neither emphasized nor particularly effective, conditions of working life did improve with economic and social stability between periods of social upheaval. After years of isolation, in which Chinese experts and institutions talked mostly among themselves and concentrated on discreetly documenting their problems, China began to share its experience and to access knowledge beyond its borders. Diplomatic recognition, first by Canada and then famously by the United States under Richard Nixon, opened a wide channel of communication with North America. Serious collaboration with foreign scientists expanded, and institutions such as the National Cancer Institute, Harvard, and Johns Hopkins took the lead in forging, and in some cases reviving, collaborations with Chinese institutions. With the sustained boom of the Chinese economy, particularly in the 1990s much has changed (4-8). State controls were lifted, the economy exploded, obsolescent state enterprises began to fail, provincial autonomy insidiously challenged Beijing, and health care and production ceased to be so centralized and controlled. The result has been an economic miracle straining the social fabric of a society with clumsy controls ill-suited to a modem state. Not surprisingly, occupational injuries and illness again skyrocketed and came to be recognized as a serious social problem with implications for sustained economic development. The Ministry of Public Health responded with renewed emphasis on occupational health, including the adoption of interim, achievable exposure standards in an effort to gain some control over the situation even if it was felt that the country could not move immediately to adopt the standards of developed countries (4, 9). Funding for occupational health and safety research, initially a priority, is falling again (at least in relative terms) because there is a mismatch between government revenues 1047-2797/97/$17.00

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and the wealth going into the private sector, which feels little obligation to support academic institutions. Today, occupational health and safety is widely recognized in official circles as a serious issue facing China but the proliferation of enterprises and unrestrained expansion of production, favorable though it may be to China’s social and economic growth, will continue to challenge the country with a high price arising from the disability of workers in their most productive years (4). China has offered an exceptional opportunity for occupational health research (5). The sheer size of the working population meant that epidemiological research could be undertaken on a scale impossible elsewhere, with cohorts of thousands wirh relatively uniform exposure histories and confounding risk f&tors, such as smoking. These workers had Lretitiably excessive exposure, often relatively well documented, to occupational hazards on a level becoming rare in the developed world, where most of the epidemiologists were and still are. Individual health data was abundant, detailed (sometimes intrusive), comprehensive, and centralized. The adv.antages to investigators included an infrastructure of research institutes, the motivation and commitment of academic centers, and the high quality of Chinese professional training relative to other developing countries (4, 5). Most , >uch as the notion that silicosis could be cured with the right herbal remedies. Resources were simply ntlt av;rMle to do research on a technical level comparable to developed countries, despite the resourcefulness and sheer intellectual power of the investigators. For a time after the tragedy of Ticnanmen, help from the outside was choked off, as outrage tn the international community forced a decrease in the level cd cc,llaboration and research activity. I--Iowe\,cr. the worst disadvantages must have been political. Workers. m;magers, and health professionals had to function under a rigid and often unpredictable political regime attempting. with variable success, to control a command economy insufficient f;x the vast country’s needs. People had to survive III :I political system that did not value candor. Distortion, censorship, and sometimes outright fiction made aggregate dat.3 sllspect and unreliable. Through the courage, discretion, and commitment of dedicated Chinese investigators, however. the raw data usually remained intact and much hecamz widely known that could not be published. Chinese investigators worked between a shadow world of their commitment to truth necessary tiction to survive, md c and naticinal progresb.

In the end, it was these investigators who prevailed. Especially, it was the older generation, many now passing from the scene before they have been recognized outside China, who conducted studies at personal risk, who taught the current generation to be truthful and who maintained the data sets that preserve an accurate picture of those years. Their motivation arose from both personal integrity and humanitarian concern. Above all, the wtfrkers and people of China have stood to benefit as the problems they experienced have been identified and exhaustivelv Jocumenred. Slow as it may be, scientific documentation has been the only reliable way yet found to stimulate ;rctictn. China’s social transition remains problemat&. with human rights at the core of world concern. The conduct of epidemiological research in collaboration has introduced an ethical framework based on “western” liberal vailtes. It is one contribution to the influence of idea:, rh;il come from actually working in China and engaging ir- ~oll:&)rati\~e work with our Chinese colleagues. This :> bog. ideas are introduced, disseminated, discussed, and mternalized in a society that is almost hermetically self-contained. China is not resistant to foreign influence; it has ;&sorbed foreign influences tor centuries. Rather, it is a sc~I?+&332ncial universe in which new ideas, once introduced. must hc worked into the fabric of what already exists if the\ r:tutfons. One hopes that over time these strands will bef.:)m~’ wI oven int-o strong ropes in a net of human rights proh~.mllg individual Chinese citizens as strongly as thcv Jo c~tl .<:I-)?in I hc WMern, liberal democracies. (%ange in China is characterized b., ::rcat~!- mobility, decentralized services, more personal prlv,ic.y ;md dispersal workplaces, with implications for epidemil ~loi,rlcal research. As China converges on other c~,nternp KXI’ socteries, ifs distinctive research culture has become ini IK mtc‘rnational in method and style, leas desperate m tom’, ,lnd mq)rt’ directly linked with social policy. It is d measure 01 ~~ptunism and progress that one of the achievements J~~~irlbeti in @to and colleagues ( 1) is a biological specimi.n repo>itory for prospective studies. This is a commitmtht-i: ii) rhc itmIre that assumes stability. Chinese occupational ~~p~~lerni~&.)gyhaa come of nge on its own terms and ha4 a !:rilll;rnt. and c)nc hopes secure, future. Tee L. Guidotti, nli?, Ml‘ti University of Albzri 2, i)epartmcnt

of

5. Moffat AS. 248:553-554.

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