A giant U.S. study meant to help decide whether cellphones cause cancer is coming back with confusing results.
A report on the study, conducted in rats and mice, is not finished yet. But advocates pushing for more research got wind of the partial findings and the U.S. National Toxicology Program has released them early.
The findings are giving new life to the longstanding debate over whether cellphone use might cause cancer.
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They suggest that male rats exposed to constant, heavy doses of certain types of cellphone radiation develop brain and heart tumors.
But female rats didn't, and even the rats that developed tumors lived longer than rats not exposed to the radiation.