Excessive exposure to high-frequency EMFs is known to harm human DNA and cells. However, you are unlikely to be exposed to amounts high enough to damage your health in your regular life. The majority of exposure occurs in tiny doses. Large exposures, according to the scientific literature, can cause DNA or cell damage. Reliable Source. Low quantities of this sort of radiation are produced by medical devices such as X-ray imaging machines and CT scans. Despite the significant study, there is no evidence to infer that low-level electromagnetic field exposure is hazardous to human health.