Social media app TikTok has come under scrutiny from the US government
A lawsuit filed against TikTok says users can become addicted after viewing just 35 videos on the app. AFP

TikTok can become addictive after viewing videos on the wildly popular act for just 35 minutes — an obsession that company executives were well aware of but kept secret, according to a report by National Public Radio.

The revelations emerged from a two-year investigation into TikTok by 14 attorneys general that led to a lawsuit against its Chinese owner ByteDance on Tuesday, NPR reported.

The internal communications among executives show that they disregarded issues about the harmful qualities of the app, despite their own research confirming those safety concerns.

The information came to light when redactions in one of the lawsuits, all filed separately, were faulty, NPR said.

When Kentucky Public Radio copied-and-pasted excerpts of the redacted portions, 30 pages of documents previously kept secret were revealed.

The lawsuit alleges TikTok was designed with the intention to hook young people on the app, but deceived the public about the risks, the report said.

According to the suit, TikTok was fully aware that someone could form a habit after viewing 260 videos.

After that, the suit says a user "is likely to become addicted to the platform."

While the number of videos "may seem substantial, TikTok videos can be as short as 8 seconds and are played for viewers in rapid-fire succession, automatically," investigators from Kentucky wrote.

So in "under 35 minutes, an average user is likely to become addicted to the platform," it said.

Another document revealed that the company knew that the app's features created an irresistible urge to keep scrolling.

The research found that "compulsive usage correlates with a slew of negative mental health effects like loss of analytical skills, memory formation, contextual thinking, conversational depth, empathy, and increased anxiety," the suit states.

The documents also show that TikTok realized that "compulsive usage also interferes with essential personal responsibilities like sufficient sleep, work/school responsibilities, and connecting with loved ones."

TikTok criticized NPR for making the documents public.

"It is highly irresponsible of NPR to publish information that is under a court seal," spokesman Alan Haurek said. "Unfortunately, this complaint cherry-picks misleading quotes and takes outdated documents out of context to misrepresent our commitment to community safety."

He said the company has safeguards "which include proactively removing suspected underage users, and we have voluntarily launched safety features such as default screentime limits, family pairing, and privacy by default for minors under 16."