Doctors have been unable to establish whether the death of a South Lopham man was linked to his former job in a mill making animal feed.
Malcolm Flatman, 66, died at West Suffolk Hospital on August 17 last year after being admitted with pulmonary fibrosis.
An inquest last Friday at Bury St Edmunds heard that Mr Flatman’s condition rapidly deteriorated and he died.
Mr Flatman, of Low Common Road, had previously been diagnosed and treated at the hospital for the same condition after suffering breathlessness.
A post mortem examination conducted by consultant pathologist Dr Mohamed Dada confirmed the presence of pulmonary fibrosis and that death had also been due to pneumonia and heart disease.
Dr Dada said that detailed examination of samples from Mr Flatman had failed to establish whether his lung condition was connected with his former employment as a mill worker.
Mr Flatman had worked in dusty conditions producing feeds for poultry and pigs.
Dr Dean said: “Looking at all the evidence, we are not in a position to know whether the pulmonary fibrosis was work related or from other causes.” The coroner recorded a narrative verdict that Mr Flatman died as a result of pulmonary fibrosis, bronchial pneumonia and heart disease.