The relationship between exposure to electromagnetic fields (EMF) and human health is of increasing interest. Exposure to EMF has been linked to leukemia and brain tumors in some but not all epidemiological studies. The effects of separate and combined alternating electric and magnetic fields on interleukin 1 (IL-1) and interleukin 6 (IL-6) production were measured in this study. Helmholtz coils and parallel plate electrodes were used to create uniform field characteristics (300 V/in., 0.3 mT). Effects were studied at a combined field frequency of 60 Hz. This frequency did not elevate culture temperatures above ambient room temperature. Murine thioglycollate-elicited peritoneal exudate cells (PEC) were exposed to an electric field (E), magnetic field (M), combined electric and magnetic field (EM), or no field (control). Three samples of PEC from each mouse were cultured with lipopolysaccharide in each field. Using commercial ELISA kits, supernatants of cell cultures were tested in duplicate after 24 hours of exposure for IL-1 alpha levels and after 48 hours of exposure for IL-6 levels. Results were evaluated using one-way analysis of variance (ANOVA). As a group, IL-1 production by the PEC from five mice and IL-6 production by the PEC from nine mice were unaffected by electric, magnetic, or combined electric and magnetic fields. Results from these experiments indicate that the 24-hour exposure to 60 Hz electric, magnetic, or combined electromagnetic fields had no effect on IL-1 production. Forty-eight hours of exposure to the same fields did not affect IL-6 production.