mole poison killed a retired farmer, an inquest heard.
Peter Greenwood, 86, from Colden, near Hebden Bridge, was estimated to have taken around a quarter of a teaspoon of strychnine.
Coroner Tim Ratcliffe returned an open verdict, saying it was not clear how the grandfather came to have taken the poison.
Mr Greenwood was seen by his son Stephen on the morning of April 25 after ringing to say he was unwell.
After making him tea and helping him take his usual medication, Stephen went home for around an hour and a half to finish work on his farm before returning to see his father. He found him on the settee and, realising he was not breathing, called police.
All the drawers of a cupboard in the hall were open.
Stephen said the bottom two were used for food while medication for farm animals – often lethal – was stored in the top.
“My dad never threw anything away so there was medicine that had been there for donkey’s years,” he said.
He had never seen his father using strychnine to poison moles, as nowadays traps were set for them.
Next to Mr Greenwood was a small jar labelled “Poison” and “strychnine hydrochloride,” dated March 1980.
There was also a rusty Lyles’ Golden Syrup tin which, the inquest heard, the jar could have fit inside. The cause of Mr Greenwood’s death was initially recorded as bronchial pneumonia but when toxicology tests came back, the cause was changed to strychnine poisoning.
He was found to have 30mg of the poison in his stomach, which analyst Richard Sykes said suggested he had ingested more than 100mg.
He said the amount of powder would have been very small – less than a quarter of a teaspoon -– but its potency would have constituted a large dose, likely to have killed within two hours.
He said this kind of poisoning was no longer common as strychnine was difficult to get hold of.
The last such case he investigated was 10 years ago.