Los Angeles (CNN) -- A lab report suggesting "Clueless" actress Brittany Murphy died from poisoning is "ridiculous" and "baseless," an expert said Tuesday.
The Los Angeles County coroner ruled pneumonia killed Murphy, 32, in December 2009, and that her husband, Simon Monjack, 39, died from the same illness five months later.
The similarities between their deaths -- in the same bedroom of their Hollywood Hills home -- prompted a search for answers beyond natural illness. Murphy's father Angelo Bertolotti sent a strand of her hair to a private lab which tested it for signs of poisoning this month.
"It's very suspicious," Bertolotti told HLN Tuesday. "I feel she was poisoned and there's no question about that. She was murdered."
Ask if he had a murder suspect in mind, her father said "I do, but I'd rather not speak about that."
CNN obtained the report by forensic toxicologist Ernest Lykissa, who concluded that the hair from the back of Murphy's head had higher than recommended levels of 10 heavy metals.
"If we were to eliminate the possibility of a simultaneous accidental heavy metals exposure to the sample donor then the only logical explanation would be an exposure to these metals (toxins) administered by a third party perpetrator with likely criminal intent."
Lykissa, who operates a toxicology testing lab in Deer Park, Texas, did not respond to several calls from CNN to discuss his findings.
The toxicology report has been interpreted in several media reports as saying Murphy and Monjack were murdered with rat poison.
The director of forensic medicine at the University of Florida, who is also the president of the American Board of Forensic Toxicology, reviewed the lab report for CNN and was very critical.
"It's ridiculous," Dr. Bruce Goldberger said. A conclusion of poisoning is an "inflammatory statement" that "is a baseless allegation and outrageous statement to make based on a single hair test."
Murphy's autopsy revealed no physical signs of poisoning, he said. "A hair test alone, without any clinical signs or symptoms, cannot be used to establish poisoning."
The private report also showed a normal level of arsenic, which would have been elevated if rat poisoning was involved, he said.
"She was a beautiful woman and likely had numerous hair treatments," Goldberger said. "Chemicals in the hair treatment would alter the chemistry of her hair sample."
The Los Angeles coroner "has no plans to reopen the inquiries into the deaths of Miss Murphy or Mr. Monjack," Craig Harvey, the chief of operations for the coroner, said Tuesday. "We stand by by our conclusions and opinion."
Although the coroner is aware that Murphy's father, ordered the private testing, the investigators have not seen it, Harvey said.
"We have not been presented with any test results and supportive documentation by any party and therefore have not been able to review any of the information that is currently making the rounds in the media," Harvey said. "We cannot comment on matters where we have not seen the data or analytical documentation."
Murphy's parents disputed the coroner's findings after Monjack's autopsy report was released three years ago.
Her mother suspected that their deaths could have been related to viral mold inside their home.
"There were no indicators that it was from mold," Los Angeles County Assistant Chief Coroner Ed Winter told CNN in July 2010.
Winter said Monjack, his mother-in-law Sharon Murphy and their lawyer all talked to him about a possible mold problem in the home during the investigation into Brittany's death.
Sharon Murphy, however, issued a statement that summer saying that she has "never been personally asked by the Coroner or anyone from the Health Department to come and inspect my home for mold."
Winter called that "an absolute lie."
"A well-respected company" tested the home for dangerous mold just two months before Murphy's death and concluded there was no mold danger, a publicist for Murphy said at the time.
Monjack's autopsy concluded that his May 23, 2010, death was caused by acute pneumonia and severe anemia, "just like Brittany," Winter said.
Murphy died December 20, 2009, from a combination of pneumonia, an iron deficiency and multiple drug intoxication, a coroner said. The drugs involved were legal and are used to treat respiratory infections, according to an autopsy.
Monjack, a British screenwriter, married Murphy in 2007.
She was an often bubbly, free-spirited actress who appeared in films such as "Clueless," "8 Mile," "Don't Say a Word" and "Girl, Interrupted."
She also lent her voice to animated works, including the movie "Happy Feet" -- in which she also sang -- and a regular role on the animated TV series "King of the Hill."
CNN's Jack Hannah and Carolyn Sung contributed to this report.