Sexual predators. Addictive features. Suicide and eating disorders. Unrealistic beauty standards. Bullying. These are just some of the issues young people are dealing with on social media — and children’s advocates and lawmakers say companies are not doing enough to protect them.

On Wednesday, the chief executives of Meta, TikTok, X, and other social media companies went before the Senate Judiciary Committee to testify as lawmakers and parents grow increasingly concerned about the effects of social media on young people’s lives.

The hearing began with recorded testimony from children and parents who said they or their children were exploited on social media. Throughout the hours-long event, parents who lost children to suicide silently held up pictures of their dead children.

“They’re responsible for many of the dangers our children face online,” the Senate Majority Whip, Dick Durbin, who chairs the committee, said in opening remarks. “Their design choices, their failures to adequately invest in trust and safety, their constant pursuit of engagement and profit over basic safety have all put our kids and grandkids at risk.”

In a heated question and answer session with Meta’s Mark Zuckerberg, Senator Hawley of Missouri asked if the Facebook founder has personally compensated any of the victims and their families for what they have been through. “I don’t think so,” Mr. Zuckerberg replied.

“There’s families of victims here,” Mr. Hawley said. “Would you like to apologize to them?”

Parents attending the hearing rose and held up pictures of their children. Mr. Zuckerberg stood as well, turning away from his microphone and the senators to address them directly.

“I’m sorry for everything you have all been through. No one should go through the things that your families have suffered,” he said, adding that Meta continues to invest and work on “industry-wide efforts” to protect children.

Only time and time again, children’s advocates and parents have stressed that none of the companies are doing enough.

“Meta’s general approach is ‘trust us, we’ll do the right thing,’ but how can we trust Meta? The way they talk about these issues feels like they are trying to gaslight the world,” said a former engineering director at the social media giant, Arturo Béjar, known for his expertise in curbing online harassment and who recently testified before Congress about child safety on Meta’s platforms. “Every parent I’ve met with a kid under 13 is afraid of when their kid is old enough to be in social media.”

Mr. Hawley continued to press Mr. Zuckerberg, asking if he’d take personal responsibility for the harms his company has caused. Mr. Zuckerberg stayed on message and repeated that Meta’s job is to “build industry-leading tools” and empower parents. “To make money,” Mr. Hawley cut in.

Senator Graham of South Carolina, who is the top Republican on the Judiciary panel, echoed Mr. Durbin’s sentiments and said he’s prepared to work with Democrats to solve the issue.

“After years of working on this issue with you and others, I’ve come to conclude the following: social media companies as they’re currently designed and operate are dangerous products,” Mr. Graham said.

He told the executives their platforms have enriched lives but that it is time to deal with “the dark side.”

Beginning with Discord’s Jason Citron, the executives touted existing safety tools on their platforms and the work they’ve done with nonprofits and law enforcement to protect minors.

Snapchat had broken ranks ahead of the hearing and began backing a federal bill that would create a legal liability for apps and social platforms who recommend harmful content to minors. The chief executive of Snap, Evan Spiegel, reiterated the company’s support on Wednesday and asked the industry to back the bill.

The TikTok chief executive, Shou Zi Chew, said the video sharing platform is vigilant about enforcing its policy barring children younger than 13 from using the app. Chief Executive Linda Yaccarino said X, formerly Twitter, doesn’t cater to children.

“We do not have a line of business dedicated to children,” Ms. Yaccarino said. She said the company will also support a federal bill that will make it easier for victims of child exploitation to sue tech companies, the Stop Child Sexual Abuse Materials Act.

Yet child health advocates say social media companies have failed repeatedly to protect minors.

“When you’re faced with really important safety and privacy decisions, the revenue in the bottom line should not be the first factor that these companies are considering,” the co-chair of Design It For Us, a youth-led coalition advocating for safer social media, Zamaan Qureshi, said. “These companies have had opportunities to do this before they failed to do that. So independent regulation needs to step in.”

Republican and Democratic senators came together in a rare show of agreement throughout the hearing, though it’s not yet clear if this will be enough to pass legislation such as the Kids Online Safety Act, proposed in 2022 by Senators Blumenthal of Connecticut and Blackburn of Tennessee.

Meta is being sued by dozens of states that say it deliberately designs features on Instagram and Facebook that addict children to its platforms and has failed to protect them from online predators.

New internal e-mails between Meta executives released by Mr. Blumenthal’s office show the president of global affairs, Nick Clegg, and others asking Mr. Zuckerberg to hire more people to strengthen “wellbeing across the company” as concerns grew about effects on youth mental health.

“From a policy perspective, this work has become increasingly urgent over recent months. Politicians in the U.S., U.K., E.U. and Australia are publicly and privately expressing concerns about the impact of our products on young people’s mental health,” Mr. Clegg wrote in an August 2021 e-mail.

The e-mails released by Mr. Blumenthal’s office don’t appear to include a response, if there was any, from Mr. Zuckerberg. In September 2021, the Wall Street Journal released the Facebook Files, which is its report based on internal documents from whistleblower Frances Haugen, who later testified before the Senate.

Meta has beefed up its child safety features in recent weeks, announcing earlier this month that it will start hiding inappropriate content from teenagers’ accounts on Instagram and Facebook, including posts about suicide, self-harm, and eating disorders.

It also restricted minors’ ability to receive messages from anyone they don’t follow or aren’t connected to on Instagram and on Messenger and added new “nudges” to try to discourage teens from browsing Instagram videos or messages late at night. The nudges encourage children to close the app, though it does not force them to do so.

Google’s YouTube is notably missing from the list of companies called to the Senate Wednesday even though more children use YouTube than any other platform, according to the Pew Research Center. Pew found that 93 percent of American teens use YouTube, with TikTok a distant second at 63 percent.