[Evaluation of the immune system in workers engaged in the production of coal derivatives].

The study involved 361 people, 161 of whom were workers of coke plants and the remaining 200 constituted the control group. The coke plant workers were divided into the exposed and non-exposed groups. All of them were subject to the following tests: rosette test, determination of B lymphocytes, determination of the concentration of IgG, IgA, IgM immunoglobulins, and NBT granulocyte reduction test only were found in group I. Subgroups Ia, IIa, IIIa were established, in which subpopulations of T, TH-helper, TS-suppressor, TH and NK (Natural Killer) lymphocytes were discovered in group Ia. The above observations can probably be associated with exposure to tar substances which contain pyrenes.