Hygienic impact assessment of emissions of petrochemical plants and petroleum refineries on cancer morbidity in a large industrial center

Introduction. Petrochemical and refinery enterprises generate up to 80 % of emissions from all stationary sources in Ufa. Air toxic pollution can threaten public health. The purpose of the study is to conduct hygienic impact assessment of emissions from petrochemical and refinery enterprises on cancer morbidity in Ufa. Materials and Methods. The authors examined the data on air carcinogen concentrations and indicators of general mortality, primary cancer morbidity, patient cohorts with malignant neoplasms and cancer mortality rate in Ufa between 2007 and 2017. They also calculated Pearson correlation coefficients and carcinogenic risks. Results. At some instants, benzene, gasoline, ethylbenzene and ethenylbenzene concentrations exceeded the maximum permissible concentration 5 times or more; concentrations of formaldehyde, benzo(a)pyrene and carbon (soot) were 2 times higher than the norm. In 2007-2017, the rate of newly diagnosed cancer morbidity increased by 6.0 %, the number of cancer patients - by 6.9 %. Over the last 4 years, cancer mortality rate reached its maximum during the given period, namely 200.1 per 100 000 people (mean value between 2007 and 2017 was 165.6±15.6). The authors revealed a close correlation between the patient cohort with malignant neoplasms and carbon (r=0.74) or ethylbenzene (r=0.63) emissions. The trichloromethane concentration was closely correlated with indicators of primary cancer morbidity (r=0.82) and mortality (r=0.78). The rate of carcinogenic risks due to air pollution was 9.0*10-4, i.e. unacceptably high. The rate of population aerogenic carcinogenic risks resulted in 1000 additional cases of malignant neoplasms. Conclusion. If there are no changes in the existing levels of air pollution in Ufa, further environmental aggravation associated with carcinogenic risks and reduction in life expectancy among Ufa residents can be possible.