After a co-worker taunted the Toll Holdings' dockhand, calling him a terrorist because he was born in Afghanistan, Mr Karzi's bosses isolated him from other workers for his own protection.

Mr Karzi complained in January 2015 after one co-worker repeatedly called him a terrorist and asked if he was a member of the Taliban. The worker who bullied him was sacked a month later.

Other members of the union protested against the sacking and Mr Karzi says they urged him to drop his complaint. His bosses moved him to another site before returning him to the depot where he first started working in 2013. He was asked to work in a sectioned off area for his own protection.

The longer he continued to work in a very small and confined wire-fenced area at Toll Holdings' Freight Depot in Erskineville, the greater his sense of alienation became.

For six months, Mr Karzi says he was not allowed to step outside the confined area "the size of a dining room" where he did data entry and moved boxes, or talk to other workers.

It felt like a cage.

Entire nights were spent tossing and turning in bed wrestling with thoughts about the way he was being treated.

"I felt hopeless and useless," he said. "I felt like, what what have I done wrong that they are treating me this way. They are calling me a bomber.

"It really damaged me. They destroyed my life."

Mr Karzi, now 34, had worked at Toll for three years before a co-worker started to single him out in 2014.

The man was reinstated after being sacked when the Fair Work Commission found in March 2016 he had not been given enough warning by management and because of his personal commitments as a bread winner and carer.

Mr Karzi, who left his job at Toll Holdings in late 2015, said the man "was always telling me: did you like it when the buildings came down and how the people died? I said why would I like it, innocent people were killed."

"He asked me if I was from the Taliban. He was always making a comment about my background and my religion."

Other  workers had sided with his abuser, who had taunted him as a "terrorist" . After the coworker was sacked, these coworkers pressed for the sacked worker's reinstatement.

Depression set in and Mr Karzi tried to commit suicide.

It was more than his wife Tania Fath could cope with. Her husband was not the same man she had married in late 2011. The pair are now divorced.

"This job has cost me my marriage. It has cost me everything," Mr Karzi said.

"My wife said to me you are not the person that I met. You don't eat, you don't talk, you go outside at three in the morning. I'm sorry I cannot tolerate this."

Last week, Mr Karzi returned to the flat he shares with a friend in Lidcombe after spending four months in hospital where he was treated for serious depression.

Ms Fath said: "I couldn't handle it anymore. He just wasn't himself."

The pair first met online and after meeting in person in Canada in late 2010, fell in love and married. The couple lived in Toronto where Mr Karzi had been living with his family for 16 years. But after a year of freezing winter temperatures, Ms Fath persuaded Mr Karzi in late 2012 to move to Australia where it was warmer. He found work at Toll Holdings the following year.

"I said it is a beautiful country, you'll really like it. I finally encouraged him to come and look what happened to him," Ms Fath said.

Still, Mr Karzi loves Australia and wants to stay.

"Five years of my life I have spent here and it is a glorious country. It is my home now," he said.

He now faces deportation back to Canada because his spouse visa was delayed for three years.

His solicitor James Saba from Shine Lawyers said the visa should have been processed in half the time, but the delay now meant he could not look for work and faced deportation.

Mr Saba is seeking compensation from Toll Holdings for two injuries Mr Karzi suffered on the job: psychological, and a back injury from lifting heavy boxes.

Mr Karzi claims members of the Transport Workers Union of which he is a member had urged him to drop his complaint against his sacked co-worker.

"The person who was accusing me was a good friend of the union delegate," Mr Karzi said.

The Fair Work Commission last year ordered Toll Holdings to re-employ the sacked dock hand at its Erskineville warehouse despite holding he had victimised Mr Karzi.

Commissioner Michelle Bissett said Toll had failed to take formal disciplinary action to ensure the sacked worker was fully aware that his conduct would not be tolerated if it persisted. The 58-year-old worker's service, age and the impact of his sacking was also taken into account. The effect of his dismissal was considered severe because he was the sole breadwinner for his family and was caring for an ageing father.

However, Commissioner Bissett said the sacked worker and those who had supported him "should not feel vindicated by my decision". Conduct such as that displayed "must be called out".

"Employees engaging in such conduct must be warned that the conduct is not acceptable and further conduct of that type may lead to dismissal," she said.

Commissioner Bissett said the comments made to Mr Karzi were designed to hurt him and "could not, in anyone's view, be considered a joke".

She said his evidence was supported by witnesses and management records and she was satisfied the sacked worker had made inappropriate comments to Mr Karzi on January 7, 2015 with respect to the Taliban and its activities and, "that in doing so, he implied that Mr Karzi would have some knowledge or would have some sympathy with the activities of the Taliban".

She said there was no excuse for the conduct and that the comments were designed to harass, vilify and victimise Mr Karzi, causing him unnecessary distress.

A spokeswoman for Toll said it takes the health and safety of its employees very seriously.

"As soon as we became aware of this incident, we started an investigation and took actions to support and protect our employee," the spokeswoman said.

She said Mr Karzi had agreed to work in the Erskineville facility which had "many distinct areas", including the "freight solutions" area where he worked with 10 other employees.

The Fair Work Commission found union delegates attempted to have Mr Karzi not formalise his complaint against the man who had taunted him.

A spokesman for the Transport Workers Union NSW said the membership of the Transport Workers' Union is a diverse group of people from a range of backgrounds.

"The TWU abhors discrimination in its many forms and does not condone bullying or discrimination in the workplace," the spokesman said.

"In the unfair dismissal case related to Toll Holdings we rely on the reasons set out in the judgment of Fair Work Commissioner Bissett as to the reinstatement.

"The TWU also echoes the sentiments of the Commissioner related to cultural and ethnic awareness, knowledge of which is gained through training, raising and discussion of issues which leads to understanding."