Screening studies among workers of modern enterprises of carcinogenic danger profile

A carcinogenic hazardous enterprise is an enterprise in which workers are exposed to or likely to be exposed to occupational carcinogenic factors and / or there is a potential danger of environmental contamination by carcinogens. This means that a worker can be exposed to carcinogenic substances at any stage of the production process, including obtaining, handling, storing, disposing of waste, operating and repairing equipment.

The problem of occupational cancer currently occupies a leading place in the history of the study of malignant neoplasms. This, first of all, is connected with the wide introduction and use of woodworking, rubber technical, oil refining industry. And it is these products that make a significant contribution to the development of malignant neoplasms in workers in these industries.

The long latency period (on average 15-18 years), the indistinguishability of clinical and biological signs of tumors caused by the carcinogen in the production of tumors that have arisen under the influence of non-production factors, the development of malignant neoplasms in workers who have left carcinogenic production, the increase in cancer risk due to the attendant adverse factors (smoking, alcohol abuse) - all these signs can make it difficult to determine the causative factor of the disease specifically th employee. Therefore, it is very important to recognize the donorological signs of a malignant neoplasm in an otherwise healthy worker in order to prevent the development of a clinically expressed form of the tumor, and, therefore, premature decline in the working capacity of the worker and a deterioration in the quality of his later life.

Currently, the most effective measures to combat malignant neoplasms in persons engaged in carcinogenic production are the formation of risk groups and early diagnosis of cancer. Short-term tests based on genotoxicity assessment of potential carcinogens are now actively used as methods for early diagnosis of cancer. One of such methods is cytogenetic micronuclear analysis.

It should be noted the general availability and comparative simplicity of micronuclear analysis, as well as the possibility of obtaining the necessary information in a relatively short time.

The purpose of the study is to determine the probability of the onset of a tumor process in employees of an enterprise with high technogenic pressure based on the study of the cytogenetic status.

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Scope and methods of research

For the cytogenetic analysis, 150 employees of the carcinogenic-hazardous profile were examined, while those who had acute pathology at the time of the examination were not examined, and 100 people were taken as a control group whose professional activity was not associated with high man-made loads. The chemical compounds used at all stages of the technological process belong to the 1st class (obligate carcinogens) and to the 2A class with a high probability of developing tumors in humans (according to the classification of chemical carcinogens of the International Agency for Research on Cancer).

As a result, the micro-nuclear test was performed in 250 people (each individual had 3 swabs, a total of 750).

For statistical processing, all values of micronuclei are divided into four groups:

• 0,2-0,5% о - 1N - the level of micronuclei in a healthy person;
• 0,6-1,5% о - 2N - micronucleus level, characteristic for the state of pre-disease;
• 1,6-2,5% о - 3N - the level of micronucleus, which characterizes the state of the organism with a high probability of malignant neoplasm development;
• more than 2.5% o-4N - the level of micronucleus, which characterizes the state of the organism with a critical level of probability of malignant neoplasm development.

A comparative analysis of the studied indicator of the level of micronuclei of the studied and control group for various characteristics (biomedical characteristics: age, sex, the presence of chronic pathology, production characteristics - the profession, the workload).

Results of the study:

1. It was found that 7% of the surveyed had a level of erythrocytes with micronuclei, indicating the instability of the genetic apparatus.
2. The average number of erythrocytes with micronuclei in the study group was 0.45 ± 0.06%, which significantly differs from the number of erythrocytes with micronuclei in the control group (t = 4.824 for P <0.0001).
3. The most vulnerable from the point of view of development of malignant neoplasms should be considered age groups older than 40 years. Relatively high percentage is the group of 40-49 years (36%). The second position in the age structure is occupied by the group of 50-59 years (25%). Age groups of active working age up to 29 and 30-39 years are represented in the ratio of 16% and 22%, respectively. The age group (over 60 years) is a small part among the total number of surveyed - less than 1%. Thus, among the total number of people surveyed, the greater part (more than 60%) is made up of persons belonging to the age group over 40.
4. The data of micronuclear analysis in women testify to a greater probability of development in the organism of oncopathology in comparison with men (P <0.05).
5. Compared with the control group, the indicator of micronuclear analysis in groups of people with and without chronic pathology is significantly higher. In people with a history of chronic pathology, the likelihood of developing oncology is much higher than the same indicator in the group of patients without chronic diseases.
6. Among all professional groups, the micronucleus level is exceeded compared to the control one. Reliable values are noted in laboratory technicians, apparatchiks, machinists, locksmiths, drivers, cleaners, rollers, loaders.
7. A significantly high average indicator of the micronuclear test level was revealed in the professional group "apparatchik", which is close to the 2N coefficient, which determines the average risk of malignant neoplasms.
8. A high risk of developing malignant tumors exists among groups with an experience of 10-19 years, 20-29 years, 30-34 years, the smallest - with experience of up to 9 years.

Conclusion

Determination of the cytogenetic status of workers in carcinogenic dangerous production allows to identify risk groups for the development of oncological diseases and can be used as a screening complex in conjunction with other methods for early diagnosis of production-conditioned malignant neoplasms.

 
Doctor of Medical Sciences, Professor of the Department of Hygiene, Labor Medicine with a course of medical ecology Sitdikova Irina Dmitrievna. Screening studies in workers of modern enterprises of carcinogenic danger profile // Practical medicine. 8 (64) December 2012 / volume 1