Korean J Epidemiol.  1996 Dec;18(2):131-141.

Problems and Suggestions for Improvement in Epidemiological Study of Coal Workers' Pneumoconiosis in Korea

• Yun IG
• Lim Y
• Lee WC
• Meng KH
• Yim HW

Abstract

Pneumoconisosis was the first reported occupational disease in korea and was the most common occupational disease until 1990. Nowadays pneumoconiosis is the second most common occupational disease which accounts for more than at least 40% of all the occupational diseases in Korea. Many studies have been carried out in the prevalence rate, incidence rate, and risk factors assessment of pneumoconiosis. Workers exposed to dust used to take health examination once annually by the Industrial Safety and Health Act(1981). The number of coal workers has steadily decreased due to coal rationalization projects which have been strongly driven by the government since 1988 and the occupational environment has been improving. So, the incidence rate of pneumoconiosis will probably be lower in the future. But a disease control system administed for patient control and compensation, which is not involved in epidemiologic studies may not figure out the prevalence rate, incidence rate, mortality rate and the extent of severity of pneumoconiosis. Several problems and expected solutions are mentioned here as follows: 1. workers exposed to dust and pneumoconiosis patients are under government control, but the retired workers are not. Since we evaluate only visiting retired workers, we don't know exactly the current status and whole scale of the retired workers. If possible, the construction of cohort in all the retired workers is needed. 2. Since most of pneumoconiosis patients retired from the work and had changed their job, it is difficult to figure out the prevalence rate of pneumoconiosis just depending on the annual health exam for those workers at risk. So, systemic control for all pneumoconiosis patients is needed. 3. It is difficult to diagnose the onset of pneumoconiosis. We make a decision the time when the patient is diagnosed with pneumoconiosis on its onset. It is difficult to estimate it, especially in the case of retired workers because we can evaluate only persons with respiratory symptoms. The solution of such a problem is construction of cohort in all of the retired workers. 4. Because the patients who died outside of hospital don't seem to be reported, the mortality rate of pneumoconiosis is underestimated. So, systemic control and follow-up observation for all pneumoconiosis patients is needed. 5. A definite severity classification criteria for pneumoconiosis hasn't been established in Korea. We should try to make one. 6. Since workers who had exposed to dust in various mines at least 1 yr are subject to pneumoconiosis laws, workers easily don't report their full dust exposure history. Therefore we can't obtain the exact lifetime dust exposure from administrative data. We should try to make basic raw data of whole dust exposure in workers. It's concluded that the construction of cohort in workers who are or were exposed to dust in various mines is required and epidemiologic study of pneumoconiosis should be carried out with the administrative control of pneumoconiosis side by side. With the database of these materials, we can speculate and devise the measure for the further affecting subjects who are presumed to be most common in manufacturing industries.

MeSH Terms

Classification
Coal*
Cohort Studies
Compensation and Redress
Dust
Epidemiologic Studies*
Follow-Up Studies
Humans
Incidence
Jurisprudence
Korea*
Mortality
Occupational Diseases
Pneumoconiosis*
Prevalence
Rationalization
Risk Factors
Coal
Dust