Social media's safety reckoning

Twitter co-founder and CEO Jack Dorsey. Photo: Michael Cohen/Getty Images for The New York Times

Facebook and Twitter are rolling out sweeping public relations campaigns, as well as product and operational changes, to re-assure critics that their products are safe for their users' health.

Why it matters: These companies see their business interests as intertwined with their ability to meet head-on the criticism that their products may be public health risks, and get ahead of scrutiny from global regulators.