Dr Nina Zimmerman was contracted by the United Nations to visit Nauru in April and gauge the level of mental disorder within the group of about 1000 refugees and asylum seekers marooned there.
She said the UN's reluctance to publicly release her findings and the indifference of the Australian government to her report had forced her to speak out.
"As a professional I'm unable to witness such a degree of mental distress and disorder on such a catastrophic scale and do nothing about it," said Dr Zimmerman.
"It's my duty to advocate and do something to get the information out there. The public have a right to know and maybe through pressure from the public we will actually get some sort of decent policy from our government."
Recruited by the UN refugee agency due to her expertise with populations in detention, Dr Zimmerman's mission to Nauru required her to interview refugees and asylum seekers within the detention camp and those living in the island's settlements.
She found 81 percent of those she surveyed were suffering disorders due to their indefinite detention, the second highest rate ever recorded in a group of refugees.
"There's been a study done on Syrians who are fleeing and find themselves in central Europe," explained Dr Zimmerman, putting her findings into context.
"These rates are two to three times higher than what you find in those refugees... three times higher than what you see in the imprisoned populations in Australia."
Conditions at the Australian-funded detention camp on Nauru, with its rows of tents pitched in what Dr Zimmerman described as "phosphate rubble", were worse than any prisons the psychiatrist had worked in in Australia, she said.
"It's really hard to even begin to make that comparison because these are people who have not committed any crime," she said.
"There are certain rights that prisoners have and the people living in Nauru simply don't have any structures that they can go to to complain.
"I have never seen people living in poorly ventilated tents. This is how children are living in camps in Nauru.
"There's no way that those kids can develop normally"
Public pressure on the Australian government to release the detainees, especially children, is mounting, despite the Abbott administration's decision to ignore the same recommendation when made by the Australian Human Rights Commission in February 2015.
Contained within the commission's 'Forgotten Children' report, the document was called the"blatantly partisan" by former prime minster Tony Abbott who told commissioners they should feel ashamed.
In February 2016, the Australian High Court ruled that offshore detention was legal, which Dr Zimmerman said sent mental health amidst detainees on Nauru spiralling out of control.
"There had been a lot of hope among the refugees and asylum seekers that that was going to go the other way and there was a lot of despair after that finding and an increase in self harm and suicide attempts."
Such behaviour from refugee children was among the most chilling data Dr Zimmerman collected on Nauru.
"They're seeing their parents in states of depression, engaging in acts of self harm and suicide. The children are following suit," she said.
More graphic descriptions have been provided by Sydney paediatrician Professor David Isaacs, who said he had seen evidence that a six-year-old had tried to take her life.
"A six-year-old. I've never seen that in my life before," he said.
"All the children I saw were traumatised in one way or another. I saw children who were self harming... I saw a boy who sewed his lips together as a protest and collapsed after three days and had to be resuscitated. This is what I saw all the time, children that were suffering from what we're doing to them."
Dr Isaacs, like Dr Zimmerman, said he considered his whistle-blowing a matter of professional integrity
Employed by a private company contracted by the Australian government to provide healthcare to detainees on Nauru in 2014, Dr Isaacs risked prosecution for revealing the atrocities he witnessed.
Prevented by the Border Force Act from releasing information about Australia's offshore prisons, the noted paediatrician challenged the prime minister to arrest him.
"What I want is for the act to be challenged in court," Dr Isaacs said in January.
"It's a law that silences freedom of speech and it's not the sort of thing one expects from a democratic country."
Nor was indefinite detention, according to an asylum seeker on Nauru who fled persecution in Iran to where he hoped he would receive a humane welcome in Australia.
After witnessing the self-immolation of 23-year-old Omid Masoumali in April, the asylum seeker, who wanted to remain nameless, said the mental pressure caused by three years of detention had prompted the action.
"This is not logical and fair," said the asylum seeker from a hospital on Nauru as Mr Masoumali recieved treated before his death.
As friends and family waited for news, the asylum seeker said a pregnant woman who had also attempted suicide was rushed into the clinic.
"Everyone around here, they're just dying every day and waking up tomorrow and tasting the same bitter life by cruelty of the government of Australia," he said.
Mr Masoumali's death was quickly followed by that of 21-year-old Somali refugee Hodan Yasin, who also set herself on fire during Dr Zimmerman's mission.
Despite accusations from both the governments of Australia and Nauru that the self-immolation was inspired by the mission's presence, Dr Zimmerman argued that "for a man to set himself alight indicates a degree of distress and despair that is beyond just making a protest".
Retired Australian general Jim Molan seems less concerned about conditions on Nauru and in Australia's other offshore detention centre, on Papua New Guinea's Manus Island.
Mr Molan, one of the so-called architects of Australia's border protection policy, told ABC this month "no Australian should feel embarrassed about what we're doing for refugees in the world".
"I haven't been to Nauru. I have been to Manus and I have been to refugee camps all over the world … I have seen enough information to convince me that if you go to Nauru you will find the most extraordinary medical facilities that most Australian towns would give their right arm for," he said.
"We are so far ahead of refugee camps throughout the world compared to Manus Island that it is not funny."
Manus Island detainee and Kurdish Iranian journalist and Behrouz Bouchani is in no mood to laugh.
This week, he estimated that more than half the 900 men held on Manus take medication for mental disorders that, according to Dr Zimmerman, afflict 88 percent of the population detained there.
Mr Boochani's fight against the policy that has kept him imprisoned for three years won him a social justice award on Tuesday from the Diaspora Symposium, held at the New South Wales Parliament.
From Manus Island, the detainee dedicated his award to the women detained on Nauru, who he said were at the forefront of the fight for refugee rights and "pioneers in a new form of resistance".
He also issued a challenge to notable Australians to join him in criticising their country's system of offshore detention.
"Academic people, writer people, artist people. Those people that they can make change and put pressure on the government. Why they are silent?"