Abstract :
[en] Research studies during the last decade have shown the roles of occupational and individual factors in occupational injury but a few information is available regarding their interplay. This study aimed at assessing the roles of occupational hazards and exploring their contributions to the occurrences of injuries among the Indian and French coal miners. In this study two surveys were conducted. The survey in India was a matched case-control study including 245 miners with an occupational injury during the previous two-year period and 245 controls with no injury from two underground coal mines located in the southern part of India. A standardized questionnaire was completed by trained personnel through face-to-face interviews. It included age, experience, sleep disorders, regular alcohol consumption, chronic diseases, smoking habit, number of dependents, occupation, and occupational hazards. The survey in France was a retrospective study on 516 coal miners randomly selected among those aged 32-47 years, from underground mines located in the north-eastern France. The subjects completed a questionnaire including socio-demographic characteristics, health-related behaviours, obesity, chronic diseases, psychotropic drug use, self-reportedpersonality traits, a 14-item biomechanical exposure scale, a 4-item physical exposure scale, and injury during the last two years. The data were analyzed using logistic model for the coal mines in France. The conditional logistic model was used for the matched case–control data from Indian mines. The annual rate of injuries (with sick leave) was 2.7% for the coal miners in India and 14.9% for the coal miners in France. Logistic model including all occupational factors showed that for the
Indian coal miners, material handling had the highest OR (odds ratio) (3.30), followed by achinerelated hazards (2.64), hand tool-related hazards (2.21), environment/work conditions (2.10), and geological/strata control (2.01). Further adjustment for personal factors led to a substantial decrease in the OR for hand tool-related hazards (OR 1.24, reduction: 80%) and achine-related hazards (OR 1.19, reduction: 88%) and to a substantial increase in the OR for material handling (OR 5.15, - 80%), environment/work conditions (OR 2.63, -48%), and geological/strata control (to 2.35, -34%) for Indian mines. Among the French coal mines, the ORs were 3.01, 3.47, 7.26 for biomechanical exposure scores 1-4, 5-7, and ≥ 8, respectively (vs. score 0). For French coal miners, personal factors contributed to <6% of the biomechanical exposure-injury association. Among Indian coal miners, hand tool-related and machine-related hazards were significant for the <45 age group only and further adjustment for personal factors led to a decrease in their ORs by 91% and 35%, respectively. The OR for material handling increased by 513% for the <45 years age group and by 77% for the older age group. The OR for environment/work conditions increased by 65% for the <45 years age group and by 204% for the older age group. Among French coal miners further adjustment for personal factors increased the OR by 11% for the <40 years age group and decreased the OR by 26% for the older age group. Coal miners from India and France were exposed to numerous occupational hazards which played high roles in occupational injury. Personal factors had a modest confounding role among French coal miners. About the Indian coal miners, it may possibly be inferred that the combined role of personal factors increased the risk of injury for some occupational hazards such as hand tool-related hazards and machine-related hazards This knowledge may be useful when designing prevention for occupational injury.
