The $25 Million National Toxicology Program Study

They wanted to find out the US the US government and the development of malignant cancers in male rats when exposed to radiation from 3G phones

Finally, on November 1, 2018, they published their report.

What they found:

6% of the male rats exposed to the highest dose of cell phone radiation developed malignant schwannomas in the heart, while 2 to 3% developed gliomas in the brain