Iain MacKenzie used to bag Munros and cycle every day, and believed he was fit and healthy his whole life.
But two years ago, the 85-year-old learned he had been poisoned by the deadly substance after he started getting breathless.
He has since found out he suffers from pleural plaques and pleural thickening, having worked with roofing sheets in the 1960s.
Mr MacKenzie, from Partick, Glasgow, believes thousands more are affected and called on Scots to raise concerns with NHS medics and charities like Clydebank Asbestos Group (CAG).
He said: "Doctors don't routinely ask if asbestos was present in your past - which is strange in itself given Glasgow's working heritage - so you need to flag it up if they don't.
"Even family members could be affected because it would be common for tradesmen to come home with asbestos on their clothes.
"I still feel lucky as there's worse conditions to be diagnosed with but there must be hundreds, if not thousands, more unknowingly suffering worse conditions than me.
"You need to act now as these steps are also for your family too as it's them who care for you and pick up the pieces."
After 10 years as an able seaman in the Merchant Navy, Mr MacKenzie worked with a construction firm as a rigger erector in the 1960s.
One of his duties involved removing asbestos roof sheets - known as "lagging" - from a warehouse on South Street in Glasgow city centre.
He was never supplied with safety gloves, breathing masks or boiler suits so it is believed that is how the deadly asbestos fibres entered his lungs and skin.
Problems only became apparent when wife Helen, 67, grew concerned that he became breathless while simply putting on his socks.
The local GP referred him to an asthma specialist at Gartnavel Hospital but the specialist raised concerns and sent him to a respiratory expert at the Queen Elizabeth University Hospital (QEUH).
It was then confirmed he had pleural plaques and pleural thickening.
Mr MacKenzie said: "I was shocked by the diagnosis because it's something you think happens to other people - I know about a dozen men who contracted an asbestos-related illness.
"Over the last few years I've been diagnosed with various chest infections or pneumonia and I wonder if things would be different now if the doctor had simply spoken to me about asbestos.
"But I'm glad we know about it now because it means me and my family can get the medical, social and legal support we need."
Mr MacKenzie - who has four kids, five grandkids and one great-grandchild - is being helped by not-for-profit charity CAG.
CAG, which is holding its AGM at 11am this Saturday at Abbotsford Church Hall in Clydebank, has supported those affected by asbestos-related diseases for nearly 30 years.