Meta CEO Mark Zuckerberg is scheduled to testify on Wednesday in Los Angeles Superior Court as part of a landmark trial about social media and safety that’s being likened to the industry’s “Big Tobacco” moment.

The trial, which began in late January, centers on a young woman who alleged that she became addicted to social media and video streaming apps like Instagram and YouTube.

Lawyers representing the plaintiff contend that Meta, YouTube, TikTok and Snap misled the public about the safety of their services and knew that the design of their apps and certain features caused mental health harms to young users.

Snap and TikTok settled with the plaintiff involved in the case before the trial began.

Meta has denied the allegations and a spokesperson told CNBC in a statement that “The question for the jury in Los Angeles is whether Instagram was a substantial factor in the plaintiff’s mental health struggles.”

Last week, Instagram chief Adam Mosseri testified that while he thinks there can be problematic usage of social media, he doesn’t believe that’s the same as clinical addiction.

“So it’s a personal thing, but yeah, I do think it’s possible to use Instagram more than you feel good about,” Mosseri said. “Too much is relative, it’s personal.”

The Los Angeles trial is one of several major court cases taking place this year that experts have described as the social media industry’s “Big Tobacco” moment, because of the alleged harm caused by their products and the related company efforts to deceive the public.

Meta is also involved in a major trial in New Mexico, in which the state’s attorney general, Raúl Torrez, alleged that the social media giant failed to ensure that children and young users are safe from online predators.

“What we are really alleging is that Meta has created a dangerous product, a product that enables not only the targeting of children, but the exploitation of children in virtual spaces and in the real world,” Torrez told CNBC’s “Squawk Box” last week when opening arguments for the trial began.

This summer, another social media trial is expected to begin in the Northern District of California. That trial also involves companies like Meta and YouTube and allegations that their respective apps contained flaws that fostered detrimental mental health issues in young users.

WATCH: New Mexico AG Raul Torrez talks about his case against Meta