Jessica McCagh died of her injuries at Ninewells Hospital
A teenager who died after a blaze at the home she shared with her boyfriend had an "extremely high level" of petrol on her clothing, a trial has heard.
Tests showed that Jessica McCagh's burnt clothes had a petrol reading "rarely come across" by one forensic scientist.
The 17-year-old received 85% burns in the fire and died within hours at Ninewells Hospital in Dundee.
Stewart Blackburn denies murder by dousing her in petrol and lighting it.
On the seventh day of the trial, forensic scientist Rebecca Peplar told the High Court in Livingston she analysed various items from the flat for traces of accelerant, including petrol.
She said an initial screening of Miss McCagh's burnt clothing gave a reading of 2,020 parts per million and that there was "conclusive scientific support for the presence of petrol".
She added: "That's an extremely high level. In my experience I've rarely come across an item of burnt clothing that has had such a high reading.
"That level of reading we normally associate with the interior of petrol cans."
She went on to tell Solicitor General Frank Mulholland QC, prosecuting, that the reading was "higher, in fact" than that found inside petrol cans.
"I analysed a petrol can for a different case last week and that only had a reading of 1,400 parts per million," she told the court.
Reading from a report she compiled on her findings, Ms Peplar told the court:
"I have rarely observed such a high level of volatiles on an item of burnt clothing."
And she told the trial later: "Of burnt items of clothing, there are none that I can recall that have been at such a high level."
She told the court she once examined a cap from somebody who had petrol poured over their head before being set on fire.
That produced a reading of 600-700 parts per million, she said.
Ms Peplar told the court she examined Mr Blackburn's flat at 83, Bloomfield Road in Arbroath following the fire.
She said the pattern of damage showed the blaze originated at the top left-hand corner of the bed in the bedroom.
The trial before Lord Bracadale continues.