After weeks of investigation, officials at the Pinellas-Pasco Medical Examiner's Office determined that the cause of the May 5 death was a "projectile wound of the head" and was an accident, the Tampa Bay Times reported.
The FDA, which shares tips to avoid such explosions, notes "the exact causes of such incidents are not yet clear", though some evidence points to "battery-related issues".
The fatality may be the first blamed on a vape pen.
The device which D'Elia was using at the time of his death was produced by Smok-E Mountain, a Philippines-based vape manufacturer.
For example, in 2015, an e-cigarette exploded in a man's face in Naples, Florida, burning his face, chest, hands and lungs. But there were no recorded deaths in the study's period.More news: This Is Biggest Concern For Me About Manchester United - Former Chelsea Star
There were 195 explosions between 2009 and 2016 but none resulted in death. "No other consumer product places a battery with a known explosion hazard such as this in such close proximity to the human body", it said.
Deputy fire marshal Steven Lawrence, who attended the scene, said vape pens can "become pieces of flying debris and shrapnel". "While the failure rate of the lithium-ion batteries is very small, the consequences of a failure, as we have seen, can be severe and life-altering for the consumer".
People interested in "smoking" cessation-including combustible products and e-cigarette devices-may visit the CDC website for advice and resources.
Smok-E Mountain, however, told ABC its e-cigarettes do not explode, suggesting instead that the device's battery or atomizer was likely to blame.
"Lithium ion batteries fail in other devices as well, but in a laptop, it's on your lap", he said.
The spokeperson added that they have previously had issues with companies "cloning their batteries".