A 5-year-old autistic boy who went into cardiac arrest in his doctor's office died as a result of the controversial chelation therapy he was receiving as a treatment for his autism.

The manner of death of Abubakar Tariq Nadama, of Monroeville, has been listed as accidental while the investigation continues.

The findings released by the Butler County coroner's office don't say whether the treatment itself is dangerous or the child died from the way the treatment was administered.

In layman's terms, the administration of ethylene diamine tetra-acetate, commonly known as chelation, resulted in a lack of oxygen to the brain as well as irreversible heart damage, said Allegheny County Deputy Coroner Ed Strimlan.

The Allegheny County morgue conducted the autopsy on the child at the request of Butler County Coroner Bill Young.

"We determined there's a direct correlation between the EDTA and the lack of oxygen to the brain and the heart muscle damage. It's a total package, based on the autopsy, the histology [tissue sampling] and the toxicology [blood sampling]," Mr. Strimlan said.

The determination is sure to spark debate among parents, many of whom support chelation as a safe and effective therapy for autism. Others condemn the treatment as voodoo medicine.

The autopsy report indicates the manner of death was accidental. The other categories are natural, suicide and homicide.

Mr. Young said he said he soon will meet with Butler County District Attorney Randa Clark and Pennsylvania State Police Cpl. Ray Melder, of the Butler barracks, to discuss whether a coroner's inquest should be scheduled. He said the determination that the death was accidental could change, depending on what additional information is gleaned from an inquest, if one is held.

The Nigerian boy was brought to the United States from England last spring by his mother, Marwa, specifically for chelation therapy. Chelation is most often used in treatment of lead poisoning.

During an Aug. 23 procedure in the Portersville, Butler County, office of Dr. Roy Eugene Kerry, Tariq went into cardiac arrest.

He had been receiving an intravenous injection of EDTA, a synthetic amino acid that is approved by the Food and Drug Administration to treat heavy metal poisoning. EDTA latches onto heavy metals in the bloodstream so they can be excreted in the urine.

Within autism advocacy circles, chelation talk has been escalating as proponents report improvements in autistic children who have undergone the treatment. Though conventional medicine considers autism a neurological disorder, others believe it is a treatable condition linked to intolerable levels of metals in the bloodstream.