Remote Combined Effects of Coal Dust and High-Dose γ-Irradiation on Immune System Changes

The objective of this research is to assess the effect of combined exposure of a high dose gamma radiation (6Gy) and coal dust on the immune system values in the long-term period. The study was carried out on 40 male Wistar rats divided into 4 groups: group I, intact animals; group II, exposure to coal dust; group III, exposure to 6Gy 7-irradiation; group IV, combined exposure to sublethal irradiation and coal dust. In groups II and IV, anthracosis was caused by exposure to coal dust at a concentration of 50 mg/m3, using an exposure chamber for 90 days after irradiation. The animals of groups III and IV were irradiated once in dose 6Gy prior to the study, with the TERAGAM CO60 gamma-therapeutic device (ISOTREND spol. s.r.o., Czech Republic). The study revealed a significant immunotoxicological shift induced by coal dust and high dose of radiation separately and in combination. The combined effect of factors exhibited an obvious immunodeficiency, as compared to the separate exposure. The combined exposure to the studied factors resulted in deterioration of T-cell immunity and disruption of cytokine production accompanied by reduced resistance to neoplasms, increased tendency to allergic diseases, and weakened immunological response of the organism.