Anti-Semitism is being repackaged and disseminated to a younger generation of social media users through platforms like Instagram and TikTok, according to analysis published Wednesday.

Anti-Semitic tropes are "rife across every social media platform" but companies are failing to act, UK group Hope Not Hate, Germany's Amadeu Antonio Foundation and the Expo Foundation in Sweden said.

Hate speech remains more prolific and extreme on sites such as Parler and 4chan, but is being introduced to young users on mainstream platforms, they said in a joint report.

On Instagram, where almost 70% of global users are aged 13 to 34, there are "millions" of results for hashtags relating to anti-Semitism, the research found.

On TikTok, where 69% of users are aged 16 to 24, it said a collection of three hashtags linked to anti-Semitism were viewed more than 25 million times in six months.

"A new generation of social media users have been introduced to anti-Semitic ideas they would be unlikely to encounter elsewhere," Hope Not Hate head of research Joe Mulhall said.

But according to the report, "tech companies have the ability to affect the amount and extremeness of anti-Semitism on their platform, and many of them are completely failing to address the issue".

The report comes as Facebook, which owns Instagram and messaging platform WhatsApp, faces intense scrutiny over accusations from a whistleblower that it prioritises profit over safety and stokes division.

The European research found that on the mainstream platforms, anti-Semitism was reaching younger users as conspiracy theories, with an "unprecedented rise" during the pandemic. 

It showed Google searches for "New World Order", an anti-Semitic conspiracy theory about a secret global elite, reached their highest level for 15 years in March 2020.

The pandemic had encouraged the online circulation of new lies accusing Jewish people of being responsible for Covid-19, the report said.

It also showed that older narratives such as Holocaust denial had morphed online to "more mocking and internet-friendly forms of denial".

A Facebook spokesperson said in response that anti-Semitism was "completely unacceptable" and pointed to changes to its policies last year that more aggressively policed hate speech and Holocaust denial.

In a statement, a TikTok spokesperson said the platform "condemns anti-Semitism" and would "keep strengthening our tools for fighting anti-Semitic content".