Effects of low frequency electromagnetic fields on expression of lymphocyte subsets and production of cytokines of men and women employed in a museum

The objective of this study was to analyse the immune response to electromagnetic fields ŽELMFs. in seven men and eight women employed in a museum. The workers were exposed in a room to an ELMFs Žrange 0.2 3.6 T and 40 120 V m. induced by 50 Hz electricity for 20 h a week. Control groups consisted of 47 women and 39 men with a similar percentage of atopic subjects, age Žrange 30 51 years. and smoking habits of the workers included in the study. Levels of blood lead ŽPb. and urinary trans trans muconic acid, a metabolite of benzene Žmarkers of exposure to traffic and smoking. of the control and exposed groups were similar. Lymphocyte subsets were determined in men and women using conjugated antibodies. Serum interleukin ŽIL. 4 and interferon and their ‘in vitro’ production by peripheral mononuclear blood cells ŽPMBCs. stimulated by phytohemoglutinin ŽPHA., as well as blastogenesis of PMBCs induced by PHA, were determined in women only. ELMF-exposed women showed a significant reduction in the percentage of B and NK CD3 CD25 lymphocytes and a slight reduction of CD16 56 NK lymphocytes. They also showed significantly lower levels of interferon in serum, or produced in the supernatants by PMBCs both spontaneously and stimulated by PHA, while they did not show significant changes in serum and ‘in vitro’ produced IL-4, or in blastogenesis of PMBCs. Men working in the museum showed, in relation to the controls, a statistically significant reduction in both number and percentage of CD16 CD56 and CD3 CD25 lymphocyte subsets. On the whole, this investigation demonstrates a reduction of blood NK lymphocytes and of the production of interferon in workers exposed to low frequency ELMFs. Recent studies have shown that stress and poor lifestyle induce the reduction of blood cytotoxic activities possibly acting on nervous functions. This may suggest that ELMFs reduces blood NK lymphocytes by combined effects on the immune and nervous systems.