Kingston: An expert witness disputed earlier testimony by telling a inquest that he was unable to find any traces of the deadly-pesticide cypermethrin in samples taken from ex-cricket coach Bob Woolmer.
"No cypermethrin was found in the adequate samples from the forensic lab," professor Das Gupta said on Monday.
Gupta, head of the pesticide research laboratory at the University of West Indies, conducted a series of re-tests Nov 6 and 7 on blood samples taken from the body of the former Pakistan cricket coach.
Gupta said he re-tested eight samples from government laboratory and another five from the United Kingdom.
Last week, coroner Patrick Murphy ordered that the samples be re-tested.
Gupta's findings support those of British forensic scientist John Slaughter who also said he was unable to find cypermethrin in blood samples.
But Gupta's testimony contrasts that of other witnesses, including Fitzmore Coates, acting chief forensic officer at the Jamaican federal laboratory, who said there was so much potentially deadly cypermethrin in Woolmer's system that it could have caused his death.
Gupta said Coates' analysis was flawed.
"I found his data very puzzling and his analysis was not proper," Gupta said adding the quality of the samples may have been as good when he conducted his tests compared to the time they were first tested in March.
Woolmer, a former England batsman was found unconscious in his Jamaica hotel room on March 18, a day after his Pakistan team was humiliated by Ireland in the Cricket World Cup.
Woolmer was pronounced dead at the University of West Indies hospital but an autopsy called the death suspicious and then murder, which sparked an intense manhunt by Jamaican police until a review reversed the findings.
Deputy Commissioner of Police Mark Shields is expected to take the stand on Tuesday.