Estimation of the Professional Risk of the Formation of Malignant Neoplasm in Workers of the Navoiysky Mining and Metallurgical Combine
Purpose: To estimate the professional risk of the oncologic pathology in workers of the Navoiysky mining and metallurgical combine (NMMC) and to scientifically justify its criteria. Material and methods: Statistical forms of account (the form no. 030-6/y, summary forms No. 7 and 35-zdrav), Regional statistical management data on population morbidity and mortality for the period since 1992 to 2004, forms T-2, the registration private affairs of workers, who were discharged from NMMC, data of the regional archive of ZAGS bureau (Civil Registry Office). Results: In the retrospectively formed cohort with the subsequent prospective study, it is shown that the standardized indices of malignant neoplasm morbidity in the first group are considerably higher than those in two others, and it is higher than that in the third one. In this case, in the first group the greatest indices of morbidity were specific to age classes of 40-49 and 60-69 years, in the second group this tendency remained, but with considerably lower levels of morbidity. In the third group, the significant differences in the morbidity dependent on age were not revealed. Within entire observed period, it was not revealed even one case of malignant neoplasm in persons in age class of 30-39 years, which it did not make possible to estimate the level of professional risk. The standardized relative risk of the development of malignant neoplasm in workers of the first group is extremely high, beginning from 40 years, in the second group it reaches analogous level only to 60 year ages, but in the third group only small increase is observed (at the level of low risk) in age class of 60-69 years and risk does not exceed the level below general average for the third group without taking into account the age composition. Conclusion: according to the results of a prospective cohort study, it is established that the probability of the development of malignant neoplasms depends on duration and intensity of the exposure to the cancerogenic factors of industrial nature. For the workers of the basic production of NMMC, which is not constantly less than 60 %, the change undergo the exposure to the cancerogenic factors of operation, occurs the extremely high standardized relative risk of the occurreence of the malignant neoplasm of professional genesis, the probability of development of which in workers of this group is more than 10 times above the analogous indices in the group of comparison.