Firstly, 5G has never been tested with regard to its possible health effects.
Secondly, the previous, related technologies have, and the majority of independent studies show harmful health effects from these technologies.
Cf. this article: https://www.theguardian.com/technology/2018/jul/14/mobile-ph...
To quote from the article: "When Henry Lai, a professor of bioengineering at the University of Washington, analysed 326 safety-related studies completed between 1990 and 2006, he discovered that 44% of them found no biological effect from mobile phone radiation and 56% did; scientists apparently were split. But when Lai recategorised the studies according to their funding sources, a different picture emerged: 67% of the independently funded studies found a biological effect, while a mere 28% of the industry-funded studies did. Lai’s findings were replicated by a 2007 analysis in Environmental Health Perspectives, which concluded that industry-funded studies were two and a half times less likely than independent studies to find health effects."