A microbiologist who assessed a mould problem in Australia's refugee detention centre on Nauru says it posed a serious health threat.
Cameron Jones was hired in 2014 by the centre's operator Transfield, from which at least a dozen former staff are reported to have developed medical problems.
Dr Jones says mould was not the only problem he found.
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Australia's health and saftey agency says it found no significant mould problem on Nauru last year.
But the Guardian reports mould remains prevalent across the centre.