When two Canadian teens were hit and killed by trains on opposite ends of the country this week, the similarities between the two tragedies were immediately striking.

In Alberta, 19-year-old Daniel McPherson was walking near train tracks south of Edmonton Wednesday afternoon when he was struck by a train. McPherson was wearing an iPod with ear-bud headphones, Alberta RCMP said.

Two hours earlier, 16-year-old Jacob Hicks had been struck by a train in broad daylight in Oshawa, Ont. Hicks was also wearing headphones when he was hit.

But as tragic as the similarities are between the two deaths, the incidents illustrate what's becoming a growing problem, especially among youth.

Hours before the Albertan teen's funeral on Friday, grieving family members told CTV Edmonton that they had repeatedly warned about being mindful of walking with headphones.

"I know Daniel had the music high, that was how he listened to it. I'm sure that's why he didn't hear a thing," said grandmother Dianne Maneschyn.

"Look what can happen, be aware of your surroundings, know what's happening, take notice. Don't be in your own world. If you have the headphones, don't have them on so loud. It can change in a split second."

According to a new U.S study, the number of deaths involving pedestrians wearing headphones has risen dramatically in the past seven years.

The most striking statistic of the research: between 2004 and 2011, the number of headphone-related incidents in pedestrian deaths rose three-fold in the U.S.

In 2004, 16 such cases were reported in the U.S. But by 2011, that number stood at 47.

While the statistics aren't available in Canada, given comparable sales of personal audio devices and smartphones in both nations, the statistics could be similar.

Led by Dr. Richard Lichtenstein, the U.S. study found that a vast majority of headphone-related deaths involved young males: 68 per cent of the victims were male and 67 per cent were under the age of 30.

Lichtenstein, a pediatrics professor at the University of Maryland School of Medicine, told CTVNews.ca in a phone interview this week that he decided to launch the study after reading about the death of a teen killed at a rail crossing.

Media reports at the time said the teen was wearing headphones and had not responded to warning calls from the train.

While auditory deprivation is a main problem, there is more to it than just sound, says Lichtenstein.

"It's probably easy to walk and chew gum, but if you're focused on your music, you may not be paying attention to the traffic around you," Lichtenstein said.

In fact, about 55 per cent of the total number of headphone-related pedestrian deaths in the study involved trains, and a warning call was sounded in about 30 per cent of the fatalities.

In Lichtenstein's research, he writes about a phenomenon called "inattentional blindness," which occurs when several sources of stimulation drain the brain's ability to allocate its finite resources.

The study purposely left out accidents linked to the use of cellphones and texting, he said, but he noted that the two areas definitely have crossover, since "we know that people who are using smartphones can have headphones in place."

"It's clearly touched a nerve," he said of his research. "I think this is something definitely that people recognize as a problem."

How to curb a growing problem?

But the problem may get worse before it gets better, especially as the style of headphones changes.

In recent years, consumer taste has shifted to high-end headphones, including large, ear-covering models like those developed by hip hop producer Dr. Dre.

That shift is illustrated by his Beats by Dr. Dre brand, which accounted for 42 per cent of US$1.2 billion in headphone sales last year. Lady Gaga and Justin Bieber are also launching similar signature brands.

It's something that registered audiologist Celina Wei has witnessed first-hand in her work at an Edmonton clinic.

But Wei, who works at the Living Sounds Hearing Centre, said the style of headphones themselves may not be the true source of the safety issue.

"A lot of the new-style headphones are made to lower environmental noise, so that the person actually doesn't have to crank their music so loud," she said.

"I don't think it's as much the headphones, but the volume at which they have their music at. If it's loud enough that they can't hear anything environmentally at all, especially horns and sirens, then it's just too loud."

In response, some jurisdictions have moved to control the use of headphones in public.

In Quebec, it's illegal to cycle with headphones on, with fines for infractions.

In the U.S., Delaware, California, Maryland, have similar laws stating that cyclists must always have one ear uncovered during riding.

But when asked about solutions, researcher Lichtenstein said that drafting new laws may not have the desired effect, because it would be "cumbersome" to enforce.

"Education and awareness are really one of my main goals," he stressed.

But as society gets increasingly attached to gadgets like iPhones, Lichtenstein said the implications can be serious.

"At best, when wearing headphones, it is difficult to carry on with a conversation, at worst, we can't hear warnings and run the risk of being hit by a train."