Douglas Swire died at Royal Cornwall Hospital last year following a period of poor health, which included respiratory problems.
In the early 1960s, Mr Swire worked as an accountant for Mullard Colour Tubes, a glass manufacturing firm in Burnley, Lancashire, where he was born.
The firm was based on a site which, in 2004, was the subject of a report into potential contamination, including asbestos.
The inquest heard that although Mr Swire, who worked in an office and not in the main factory, it is “certain” that he came into contact with the harmful mineral.
Stephen Covell, assistant coroner for Cornwall, said there is evidence that asbestos was present in the factory in the form of insulation wrapped around furnace ducts or pipes. Mr Covell said:
“I find that there is evidence to persuade me that certainly during that time, Douglas would have been exposed to asbestos fibre. In the 1960s, the dangers of asbestos were not known.”
Mr Covell also said that it was possible, although not certain, that Mr Swire came into contact with asbestos in subsequent employment in Durham, and later in Bodmin. Mr Swire moved to Cornwall in the early 1990s.
Mr Swire’s daughter, Susan, also told the inquest that her father enjoyed DIY, which included once taking a storage heater apart, and often coming across old sheds and garages.
However Mr Covell said he was “not convinced” that this possible exposure caused Mr Swire’s disease.
A post-mortem examination, carried out by pathologist Dr Juliane Stolte, found that Mr Swire died of mesothelioma, a cancer of tissue in the lungs which is especially associated with exposure to asbestos.
In August last year, a CT scan identified irregularities in Mr Swire’s right lung, the inquest in Truro heard.
He subsequently developed chest pain and breathlessness, and after a period in hospital, died on September 20 after suffering a cardiac arrest.
Concluding the inquest, Mr Covell said:
“In order for me to reach a conclusion of industrial disease, I have to be persuaded that Douglas died of a disease caused by his work.
I don’t have to come to the conclusion as to which period of employment caused the disease, but I do have to be satisfied that exposure at work caused it, and not exposure outside of work.
The evidence of [pathologist] Dr Stolte also determines that scarring of Mr Swire’s lungs was longstanding, and the employment at Mullards in the 1960s was longstanding.”