By CBSNews.com's Stephen Smith
New York City's medical examiner ruled that a retired detective died last year from misusing drugs - not from toiling for 420 hours in the ruins of the World Trade Center, the cop's family revealed Thursday.
Charles Hirch's ruling on James Zadroga came five months after Zadroga's parents, Joseph and Linda Zadroga, had given their son's autopsy report to the medical examiner in a bid to have their son's name added to the official list of Sept. 11 victims.
Despite Hirsch's ruling, the city's former medical examiner, Dr. Michael Baden, disputed the claim. Baden said that the 34-year-oldwas indeed linked to his exposure to the toxic debris at ground zero.
"There's no evidence of any drug addiction," Baden said, who added that all the evidence supports that Zadroga "died of chronic lung disease caused by the inhalation of dust" at the ground zero site.
When Hirsch ruled Zadroga's death was unrelated to 9/11, Zadroga's parents enlisted Baden for a second opinion.
Baden spoke Thursday at an interview conducted at the Manhattan office of Michael Barasch, the lawyer for Zadroga's parents. A producer from CBSNews.com and reporter from the Associated Press attended the session.
Last week, Hirsch wrote a letter to Zadroga's parents stating "with certainty beyond doubt, that the foreign material in your son's lungs did not get there from the result of inhaling dust at the World Trade Center or elsewhere."
In a private meeting, Hirsch later told the family he believed Zadroga died of drug misuse - most likely by grinding up his medication and injecting it intravenously. There was no claim of any illegal drug abuse. Zadroga was taking 14 medications, including two intravenously, at the time of his death, but all were administered by family, according to his father.
Hirsch apparently cited the talc and cellulose present in Zadroga's lungs as evidence of injecting ground-up pills.
But Baden, who reviewed Zadroga's tissue slides, autopsy report and medical records, dismissed this claim.
"Talc and cellulose are ubiquitous," he said, noting such materials could have come from furniture at the World Trade Center. He also said there was no evidence of the scarring that would have accompanied repeated injections.
Zadroga has emerged as a symbol for the plight of thousands of ground zero workers whose health rapidly deteriorated after their long days toiling in the rubble at ground zero. Zadroga spent more than 400 hours sifting through the smoldering ruins, and by the first anniversary of the attack was plagued by a constant cough.
Hirsch reviewed Zadroga's tissue slides and autopsy report, but not all of the detective's medical records, which Dr. Baden said can render an incomplete picture.
"Autopsies can't be done in a vacuum," he said.
Baden said the lack of scars or needle tracks - and Zadroga's clean bill of health prior to Sept. 11 2001 - further undermine Hirsch's ruling. But Hirsch maintains that the foreign matter in the cop's lungs "entered his body via the bloodstream and not via the airways,'' his spokeswoman told the AP.
"I suspect that there may not be a 100 percent definitive answer here," said Dr. Stephen D. Cohle, chief medical examiner of Kent County (Grand Rapids) Michigan.
Cohle, who knows both Dr. Hirsch and Dr. Baden but is not involved in this case, said that foreign materials that are mixed with injected drugs display a very specific appearance - and likely wouldn't be mistaken by someone as experienced as Hirsch. However, Cohle noted that it's unusual for chronic IV abuse to cause fatal lung disease.
Cohle also said Zadroga's heart condition can offer clues. According to the autopsy report, the right side of Zadroga's heart had swelled to twice its normal size - a condition known as right ventricular enlargement.
"Right ventricular enlargement is much more common with exposure to dusts and other occupational exposure," Cohle said.
Earlier this year, Hirsch ruled that an attorney who died of a lung disease after being caught in the World Trade Center collapse could be- the first time a person who died from a 9/11-linked illness was included in the official tally.
Baden said he supported a New Jersey medical examiner's ruling that Zadroga's death was "directly related" to his work at the World Trade Center site. Dr. Gerard Breton, who performed the autopsy, found that Zadroga died in January 2006 of respiratory failure caused by panlobar granulomatous pneumonitis (history of exposure to toxic fumes and dusts).
The autopsy results were the first scientific evidence blaming a death directly on ground zero exposure. Lawmakers and health advocates regularly cite his case as a key example of post-Sept. 11 illnesses when lobbying for billions of dollars to fund research and continuing care.
Joseph Zadroga has become a prominent advocate for sick ground zero workers, and he broke down in tears last year before a congressional panel convened to study Sept. 11 health.