Influence of xenobiotic detoxication gene polymorphisms and experience on the level of accumulation of dioxins in Emercom of Russia employees
Authors: Kriyt V. E. , Sannikov M. V. , Sladkova Yu. N. , Pyatibrat A. O. 
Published: June 2020

Relevance. Occupational activities of firefighters are considered extreme. Toxic combustion products are the most dangerous. Among these products, dioxins and dioxin-like compounds are particularly dangerous due to their ability to accumulate in the body.

Intention is to analyze the content of toxic combustion products in atmospheric air during and after fires of various locations, as well as to evaluate dioxin concentrations in the blood plasma of employees of the Federal Firefighting Service of the Emercom of Russia, depending on the polymorphic variants of xenobiotic detoxification genes and professional experience.

Methodology. To assess accumulation of dioxins in the body of firefighters with different polymorphic variants of xenobiotic detoxification genes, atmospheric air at different locations of fires was assessed for toxic combustion products. Accumulation of dioxins in the body of firefighters was analyzed depending on the polymorphisms of xenobiotic detoxification genes and work experience. 350 employees of the Federal Firefighting Service of the Emercom of Russia were examined, of them there were 234 firefighters and 116 supervisory staff involved in the investigations at the fire sites. The control group consisted of 82 rescue workers who were not directly involved in fire fighting. The examined individuals aged (32.2 ± 9.5) years.

Results and Discussion. The data obtained indicate that high concentrations of dioxins in surface air at the fire site persist for more than 2 weeks, while the maximum permissible concentration is increased 4.5-10-fold. The highest concentration of dioxins is observed during fires in industrial enterprises and in residential buildings. According to the analysis of the dioxins in the blood of the Federal Firefighting Service employees and the control group, concentrations of individual chemical compounds among the employees of the Federal Firefighting Service were 2–7 times higher and 15 times higher in terms of the dioxin equivalent compared to the control group (p <0.05). High concentrations of dioxins were also revealed in the blood of supervisory staff. Analysis of the dioxins in the blood of the staff of the Federal Firefighting Service, EMERCOM of Russia showed that increased length of service correlated with dioxin concentrations in the blood: variations in chemical compounds reached 2.3–6.8 times (p <0.05) between those with 0–1 year vs 6 years or more experience and 1.3–1.7 times (p <0.05) between those with 2–5 years vs 6 years and more experience. Concentrations of dioxins in the blood plasma of employees of the Federal Firefighting Service of the Emercom of Russia were assessed depending on the polymorphic variants of xenobiotic detoxification genes and professional experience. A group of individuals carrying the combination of the EPHX1 Tyr / Tyr, CYP1A1 A / A, GSTT1 I / I, GSTM1 I / I, GSTP1 A / A, GSTP1 C / C genotypes was revealed: their dioxin concentrations in the blood were as low as 25% of that among other groups despite length of service.

Conclusion Genotyping of firefighters will help arrange timely measures to detoxify dioxins, especially in carriers of minor alleles of xenobiotic biotransformation genes, in order to reduce morbidity and increase professional longevity.