Abstract: Objective: To discuss the effects of extremely low frequency electromagnetic fields(ELF-EMF) exposure on the function and morphology of liver,kidney and spleen of the SD rats, and to clarify the mechanism of radiation damage of ELF-EMF.Methods: Twenty male SD rats were randomly divided into exposure group and control group (n=10). The rats in exposure group were exposed in an ELF-EMF device with a magnetic induction of 0.1T and a frequency of 50 Hz; the exposure was conducted for 8 h per day for 30 d. The rats in control group didn't receive any treatment. After exposure for 30 d, the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea nitrogen (UN), creatinine (Cr) of the rats in two groups were detected. HE staining was used to detect the morphology of the liver, kidney, spleen tissues of the rats in two groups.Results: Compared with control group, the serum levels of ALT, AST, UN, and Cr of the rats in exposure group were increased(P<0.05). In exposure group,the dilatation and congestion were found in the central veios of liver and hepatic sinusoids, glomeruli and interstitial capillaries of kidney, and insinusoids of spleen of the rats; part of the hepatocytes showed necrosis. There was no abnormality morphology in the liver, kidney,and spleen tissues of the rats in control group.Conclusion: Exposure to ELF-EMF(0.1 T, 50 Hz) can affect the function and structures of liver, kidney and spleen tissues of the SD rats, and its mechanism may be related to oxidative stress induced by ELF-EMF.

Key words: extremely low frequency electromagnetic fields, rats,SD, liver, kidney, spleen