Mariah Carey has a new fear. Her fiance James Packer is a heavy smoker and she's worried about the effect on her voice and her children from secondhand smoke. (Photo: Getty)

Mariah Carey has a new fear. Her fiance James Packer is a heavy smoker and she’s worried about the effect on her voice and her children from secondhand smoke. (Photo: Getty)

Mariah Carey has encountered a potential deal-breaker in her relationship with Australian billionaire James Packer. She’s totally turned off by his heavy smoking, fearing hit will harm her voice and affect her children’s health with second-hand smoke.

This issue emerged this morning in the usually reliable Sydney Morning Herald. It quoted a source saying his smoking has “become an issue with her.”

Despite Packer’s vast bank accounts–he’s reportedly worth billions–Cary, 45, is no financial slouch herself. She also suffered under an abusive marriage at a young age to record mogul Tommie Mattola.

She’s likely only willing to go so far to accommodate his nasty habit.

“It’s her voice she worries about, and the twins too,’ the friend of the singer told the newspaper. “She doesn’t want them being exposed to James’ cigarette smoke… it’s becoming a bit of an issue.”

Carey also was once a heavy smoker. She started when she was just 12-years-old, growing up in a middle-class suburb of Huntington, New York. She quit when she was 18 and never looked back.

“I gave up smoking in one day and never went back,’ she told UsWeekly last year. “I absolutely detest cigarette smoke now.”

With good reason. Smoking, more than any other habit, is responsible for all manner of illness, from lung cancer and emphysema to colon and pancreatic cancer, according to medical references.

A slew of celebrities have died from smoking related illnesses over the years, including many stars from the early ’30s and ’40s when the dangerous effects of smoking weren’t fully known. The list includes John Wayne, Humphrey Bogart, Johnny Carson and Patrick Swayze among others.

The dangers of secondhand smoke is also well documented.

Non-smokers who breathe in secondhand smoke take in nicotine and toxic chemicals the same way smokers do. The more you breathe, the higher the levels of these harmful chemicals in your body, according to the American Cancer Society.

Secondhand smoke contains more than 7,000 chemicals, including at least 70 that can cause cancer, the organization says on its Web site.

High on the list of organs it can damage are the larynx (voice box), pharynx (throat), nasal sinuses, brain, bladder, rectum, stomach and breasts.

In children, the effects can be just as debilitating. Secondhand smoke has been linked to lymphoma, leukemia, liver cancer and brain tumors, according to the organization.

Since he’s still smoking at the age of 48, Packer is probably already suffering from emphysema and COPD and is a good candidate to contract lung cancer, depending on his genetic makeup. Heart disease is also high on the list because he used to be obese.

In 2012, he told Fox News he’d had lap band surgery to help lose weight, but that’s as far as he went. He continued to smoke.

“I’m an idiot. I (still) smoke and do all those things I shouldn’t do,” he said.

“I’ve been off them for 10 days but, you know, I don’t want to say I’m off them, mate, because you know I’ll probably have another one in a week.”

Packer has a huge incentive to quit now. Otherwise, it wouldn’t be beyond the realm of possibility for Carey to walk out on him.

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