The Center for Digital Democracy wants the Federal Trade Commission to investigate whether YouTube is illegally targeting children using ads in videos. 

"Google profits handsomely from selling advertising to kid-directed programs that it packages. It makes deals with producers and distributors of kids' online programs worldwide. Google has built a global and very lucrative business based on kids' deep connections to YouTube," Jeff Chester, executive director of CDD said. 

The CDD drafted a formal complaint to the FTC, which YouTube parent company Google (GOOGL) - Get Report , a key holding of the Action Alerts PLUS charitable trust, says it is reviewing.

YouTube is the most popular online platform for children, the CDD alleges, citing a recent study that found that 80% of U.S. children ages 6 to 12 use the video-sharing site daily. 

The firm also says that since over half of YouTube's total viewing time now occurs on mobile devices, there is a decreased likelihood that these children are being supervised by an adult when they are targeted with ads.