LAKEWOOD, Wash. — A newer car, summer heat and four coolers of dry ice combined with rare but lethal effect early Friday, accidentally killing a 77-year-old Lakewood woman.
The Pierce County Medical Examiner's Office described the cause of death as asphyxiation due to displacement of oxygen by carbon dioxide. Investigators suspect dry ice in the car was the cause.
"At this point we're just looking at this as horrific accident," sheriff's spokesman Ed Troyer said.
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The incident started with a medical aid call from a distraught University Place man, 51, who found his wife, 51, and his mother passed out in his car, Troyer said.
The man, who runs an ice cream delivery business that uses dry ice, said his mother had been visiting Thursday evening, and his wife agreed to drive her home about 11 p.m.
The man rose at 4 a.m. to go to work, and realized his wife hadn't returned. He found the car parked a few blocks away. The man's wife and mother were prone inside, and appeared unconscious.
The man said he broke the rear driver's side window with a rock, opened the car, pulled his wife out and called 911.
Emergency medical technicians from West Pierce Fire & Rescue arrived, and transported the man and his wife to St. Joseph Medical Center in Tacoma. They tried to revive the man's mother without success. She was pronounced dead at the scene.
The 51-year-old woman was in critical condition Friday, Troyer said.
Sheriff's deputies responding spoke to the man at the hospital. He explained he had stored dry ice in the back seat of the car.
“He had four coolers full of dry ice because he delivered Dippin’ Dots to various locations,” Troyer said. “He recently got a new car. The newer car probably had better sealing.”
Troyer noted he couldn't recall a similar instance of accidental death by dry-ice asphyxiation in his career.
"If you do some research on it, it's out there, it happens," he said.
Dry ice, a solid form of carbon dioxide, transforms to gas when exposed to open air. The effect can be dangerous in confined, non-ventilated spaces, according to information from the University of Washington's Department of Environmental Health and Safety.
"This releases potentially substantial volumes of CO2, which can displace oxygen quickly in the air around the dry ice, causing difficulty breathing, loss of consciousness and death."
Sean Robinson: 253-597-8486 @seanrobinsonTNT
Cox Media Group