THE man who disappeared from a hulking coal ship off the Queensland coast, and is presumed dead, may have vanished after drinking "a toxic substance".
Crew raised the alarm at 6pm AEST Thursday when the 47-year-old Filipino man could not be found on board, and about five hours after he was last seen.
By the time the Australian Maritime Safety Authority was able to launch a full air and sea search, the ship was now more than 100km away from the area, between Innisfail and Lucinda.
Rescue helicopters, and the Townsville Water Police searched until last light on Thursday.
By Friday the search area now spanned 800 square nautical miles (2743 square kilometres), and was combed with the help of AMSA's search and rescue plane, six other fixed wing planes and the same rescue chopper used on Thursday.
In total, eight aircrafts and five vessels were involved in the search.
IN CASE YOU MISSED IT: Man disappears from bulk carrier heading to Hay Point
The SBI Samba, after searching the day before, continued heading south for Hay Point, near Mackay, on Friday.
That night, experts suggested the man - if he was in the water - had run out of time, and was certainly dead.
After arriving at Hay Point on Friday evening, the SBI Samba was boarded by Queensland Police officers.
According to police, the death was not suspicious, and the man is thought to have disappeared overboard after "consuming a toxic substance".
Police were unable to elaborate on the nature of the substance but have said the death is not considered suspicious.
Officers will now prepare a report for the coroner.
A spokesman for ship owners Scorpio Bulkers said the company had been in touch with the Australian Federal Police and AMSA following the incident.
He said the company would leave the investigation in the hands of the AFP, "given it's a missing person case".
The AFP has told Australian Regional Media that Queensland Police are leading the investigation.
Scorpio are incorporated in the Marshall Islands, which has a reputation of having gentler shipping regulations and tax requirements when compared to more developed countries.
The International Transport Workers Federation represents foreign sailors aboard ocean-faring ships.
ITF Australia coordinator Dean Summers warned that too often the "man overboard" label was used to avoid a proper investigation.
"These tragedies go under-reported, demonstrating to the world that these employers think international seafarers are a disposable commodity," Mr Summers said.
In May last year, the Japanese Spring Hydrangea bulk carrier suffered one such man overboard.
Mr Summers said the ship's owners have so far failed to compensate the lost man's family.
In 2012, a Filipino cook named Cesar Llanto vanished from the coal-carrying MV Sage Sagittarius off the Queensland coast.
His death, and that of two fellow seafarers has now become the subject of a Coronial Inquest and Senate Inquiry.
"While at this stage there are no reports of foul play, the ITF wants to ensure this is not a replay of the Sage Sagittarius," Mr Summers said.
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