Daniel Motaung's petition says locally outsourced workers, who moderate Facebook posts, suffer irregular pay and receive inadequate mental health support after viewing disturbing content.

Mr Motuang says this moderating work has given him Post-Traumatic Stress Disorder (PTSD).

He was sacked after trying to get dozens of colleagues to form a union.

The lawsuit seeks financial compensation and an independent human rights audit of Mr Motaung's office. It also wants the court to order that unionisation rights be protected.

A spokesperson for Meta said it required its partners to provide industry-leading pay, benefits and support.

The outsourcing company, Sama, has previously rejected claims of mistreating its employees.