Democratic Senator Ed Markey on Monday asked for answers from Facebook chief executive Mark Zuckerberg after new research suggested the social media company failed to prevent display of harmful advertisements to teen Facebook users.

Markey cited comments by a Facebook executive before Congress last week that the site does not allow weight-loss ads to be shown to people under the age of 18 already, or any tobacco ads.

Markey said “new research shows Facebook allowed advertisers to target with exactly these types of inappropriate and dangerous content to teen users.” Facebook did not immediately comment.

Markey cited research conducted by the Campaign for Accountability’s Tech Transparency Project, that as recently as last month Facebook allowed advertisers to target teen users as young as 13 with “inappropriate and dangerous content, including advertisements promoting ‘pill abuse, alcoholic beverages, anorexia, smoking, dating services, and gambling.'”

Markey added: ““These findings cast serious doubt on Facebook’s compliance with promises your employees have publicly made, and they are particularly concerning in light of other recent reports, which suggest that Facebook has direct knowledge that its platforms are harmful to young people.”

Haugen told “60 Minutes” in an interview that aired Sunday that “Facebook’s own research says, as these young women begin to consume this — this eating disorder content, they get more and more depressed. And it actually makes them use the app more.”

Democratic Senator Richard Blumenthal, chair of the subcommittee holding the hearing, said the testimony is “critical to understanding what Facebook knew about its platforms’ toxic effects on young users, when they knew it, and what they did about it.”

Last week Instagram, the photo-sharing service owned by Facebook, said it had hit a pause on a new app it is creating for children. – Rappler.com