Pregnant women exposed to high radiation levels from sources like cell phones, wireless devices and cell towers miscarried at nearly three times the rate as those exposed to low levels, according to new research. I hope this study makes us rethink the notion that magnetic field non-ionizing radiation exposure is safe or has no health risk," said lead author Dr. De-Kun Li. Cell phones, cordless phones and other wireless devices, appliances, power lines, smart-meter networks and cell towers generate non-ionizing radiation from magnetic fields. Writing in Scientific Reports, Li and his team call rapidly proliferating electromagnetic field emissions "a ubiquitous environmental exposure and a serious looming public health challenge." For the study, more than 900 pregnant women in the San Francisco area carried meters that measured their exposure to electromagnetic field radiation. Expectant mothers with the highest exposure levels during their typical weekday routines were 2.7 times as likely to miscarry as women with the lowest levels. The results underscore the need for additional research into possible health harms of a technology to which virtually everyone in the U.S. is now exposed, whether by choice or circumstance, Li said. A federal study last year found an increased risk of cancer associated with magnetic field non-ionizing radiation exposure in rodents. Li called the findings from the National Toxicology Program "stunningly important."