Efforts to source a laboratory which can test for the presence of a rare toxin called taxin, found in the yew seed, are under way.
They are part of an extensive inquiry to establish the cause of death of a woman whose body was found in her apartment on Christmas Day last year, an inquest has heard.
Gardaí discovered the body of Grace Caulfield (38), Westgate Apartments, Dublin, in her bed after her family raised the alarm when she failed to return home for Christmas, Dublin City Coroner's Court heard yesterday. A post-mortem at St Vincent's hospital failed to provide a cause of death.
No alcohol or drugs were detected in Ms Caulfield's system.
Dublin city coroner Dr Brian Farrell told the Caulfield family, from Monaghan, that the State laboratory was seeking a laboratory in Europe or elsewhere which could analyse her blood for the presence of taxin, a highly toxic substance found in the yew seed.
This has emerged as a result of further investigation which revealed that two containers of yew seeds were found in Ms Caulfield's apartment. This was confirmed by a taxonomist at the National Botanic Gardens.
Garda Mark Bolger of Kevin Street Garda station said a tea-like liquid containing seaweed-like particles was also discovered in a teapot in the apartment.
Adjourning the inquest to January, Dr Farrell told Ms Caulfield's family: "It's an important matter and we think you should know about it, but I don't know if it will offer any explanations."
There have been cases where livestock and horses have been poisoned after eating yew seeds.