Indicators of humoral immunity in smokers and nonsmokers working underground

A group of 215 underground shale miners (148 smokers and 67 nonsmokers) was examined for levels of immunoglobulins in sera (IgG, IgA, IgM) and saliva (sIgA), transferrin (TRF), alpha 2-macroglobulin (A 2M) and lysozyme levels in sera (LYS) and saliva (sLYS). The control group consisting of 95 healthy men was selected to match the age of the exposed miners. The mine environment was characterized by the presence of ionizing radiation, due to a geological configuration of the rock. The study revealed that the decline of IgG, IgA and sLYS levels in smokers was significantly deeper than in nonsmokers and controls. The levels of sIgA and serum LYS levels were increased both in smokers and nonsmokers. The change in the serum LYS and A 2M levels in miners did not depend on the smoking habits, except of A 2M levels in miners employed for more than 21 years. The differences were, as a rule, less pronounced in younger miners and tended to increase with the increasing length of work underground. The distribution analysis revealed some inter-miner differences in the susceptibility to these changes and the formation of smaller subgroups of miners with more or less subnormal test values, which supports the hypothesis on the heterogeneity of this population group. The tests showed that the statistical analysis of abnormal test values might play an important role in the assessment of the health risk in individuals. A simultaneous detection of subnormal values in some of pairs of tests may provide decisive data allowing a reliable differentiation between the afflicted miners and the healthy control subjects.