MAPLE GROVE, Minn. - David and Marnie Schuster were enjoying their July 4th on Eagle Lake with their children last week when their daughter, Sierra, 4, started crying.

"Crying and then not responding. Not responding to like, what's the matter. It was very unusual for her," said David.

David, who was driving the boat, was barely going 5 miles per hour while Sierra and her mom were in a tube pulled by the boat 20 feet behind the motor during a parade with several other boats. She then sat in the back of the boat.

But when their daughter started acting up, they went to shore.
"She wasn't telling us anything," said Marnie.

"She fell over like a drunk. Three steps and into the yard," added her husband.

Turns out she was starving for oxygen, suffering from carbon monoxide poisoning. They first took her to the emergency room where Sierra's symptoms seemed to already be dissipating.

"By 15 minutes all of her symptoms had resolved, she was talking, she was fine but her CO levels were almost lethal for an adult," said Marnie.

Last year one of their neighbors suffered from carbon monoxide poisoning too while on a boat, they say. That's why Marnie says she asked the doctors to check for CO poisoning. She says her daughter's levels were very high, to the point doctors rushed her by ambulance to the Hennepin County Medical Center's hyperbaric chamber.

"There are particular places on a boat that are particularly dangerous for the accumulation of carbon monoxide," said Dr. Cheryl Adkinson who treated Sierra at HCMC.

She says this sort of thing happens more often than people think, but it's likely under reported because boaters blame the symptoms on heat stroke or alcohol use.

According to the CDC, more than 800 boating-related poisonings have been identified with more than 140 resulting in death. One in four of these poisonings are attributed to generator exhaust alone.

"You can get enough of cumulated carbon monoxide in that area to make someone seriously ill or even kill them," said Adkinson.
It's why the Schuster family bought a portable CO meter for their boat. When KARE 11 went for a ride, it was detecting high readings in the back of the boat within only a few seconds on the lake. The back of the boat can often times be the worst location because it's the lowest point and close to the motor.

"This is where we would sit and watch people surf," she said. "Scary. Who knew?" 

"You feel like you're not a good advocate for your child. You do everything to keep them safe."

And that's why the Schuster's want others to remember their story, even if they may want to forget it.

"The good part about this and us telling this story, we have a happy ending," said David. "I guess our big part of sharing the story is how dangerous it can be," added Marnie.

It’s colorless, odorless and deadly, and safety officials say carbon monoxide poisoning likely contributed to more drowning deaths over the past decades than imagined. 

People don’t tend to think about the hazard when on a boat, enjoying the sunshine and great outdoors. But the dangers are real. 

“It’s a problem people don’t recognize,” Edwin Lyngar, a boating-safety educator with the Nevada Department of Wildlife, said Friday. “People will start feeling nauseous and think they’re sea sick when they actually have mild carbon monoxide poisoning.” 

Last weekend, 22-year-old Lucas Allyn died after boating at Bear Lake in Utah when he was overcome by carbon monoxide. According to The Deseret News, Allyn spent a good part of the day at the rear of a boat — near its exhaust — hoisting skiers and swimmers out of the water. 

“It happened in the open air. You would think it unbelievable until you think about how the gases recirculate near the back of the boat,” Dr. Robert Baron, a medical adviser for Glen Canyon National Recreation Area, told the newspaper. 


On Sunday, 12 people were treated in Southern Nevada after being sickened while house boating on Lake Mead. Five were flown to a hospital in Las Vegas, four were taken by ambulance and three others were treated at the scene. All have recovered. 

“They were running their generator to keep the air conditioning going,” said Christie Vanover, spokeswoman for the Lake Mead National Recreation Area. She said another boat parked next to it, causing the exhaust to circulate back into the house boat. 

Lyngar said carbon monoxide poisoning while boating “is far more common than we thought.” 

He pointed to the ban on “teak surfing,” during which people hold onto a swim platform at the back of a boat and are pulled through the water. Platforms are near exhaust systems. 

“People used to do that for fun,” he said. “There were several fatalities nationwide.” It is now illegal in many states. 

Lyngar recalled another incident several years ago on Lake Powell, a reservoir on the Colorado River along the Utah-Arizona line. A girl died after washing her hair using the exhaust port from a generator. 

“That exhaust is filled with carbon monoxide, but that spout also has warm water,” Lyngar said. 

Lyngar said a regional group that has studied deaths on the Colorado River concluded that carbon monoxide poisoning “was more prevalent than we thought.” 

“Going over the record of old accidents, we think a lot more of these are carbon monoxide-related,” he said. 

“I would say 10, 20 years ago we did not look at this as seriously as we do now,” he said. “Over the last decade or two, we’ve recognized how serious it can be.” 

Baron, who has reviewed death and illness reports on Lake Powell for more than 25 years, agreed. 

He and others have collected data showing more than 800 incidents of death or illness on U.S. waterways attributed to carbon monoxide since the mid-1990s. 

“There is absolutely many more than that number,” he told The Deseret News. “It’s still an under-recognized event.” 

Lyngar said it’s a good idea for boaters to have carbon monoxide detectors on board — and pay attention to them. Also, people should not linger in the back of a boat, near exhaust. 

“Be careful at low speeds,” he said, adding that invisible gas clouds can form quickly when boats are idling or moving slowly. 

Safety tips on avoiding exhaust problems are covered in the agency’s safe-boating programs and pamphlets. 

“We don’t want to make people afraid,” Lyngar said. “We just want to make people aware.”