By Linda So

DAYTON, Ohio, June 21 (Reuters) - Scott Weidle is struggling with the death of his son Daniel, who died from a heroin overdose 18 months ago, one day after Christmas.

Daniel, who was 30 when he died, was a father of three young boys: Dylan, Landon and Gavin.

"I got the call laying on the beach," Weidle, 58, said. "Worst day of my life."

Weidle, a sand and gravel contractor in Montgomery County, Ohio, said he could never have imagined his son becoming a statistic in the United States' growing opioid crisis.

"I have all kinds of emotions," he said. "One day it's outrage, one day I'm infuriated, and one day I'm in disbelief."

Opioid drugs, including prescription painkillers and heroin, killed more than 33,000 people in the United States in 2015, more than any year on record, according to the U.S. Centers for Disease Control and Prevention.

An estimated 800 people in Montgomery County will die this year from drug overdose, more than double the 370 overdose deaths the county recorded last year, giving it the unfortunate distinction of logging the most overdose deaths in the country per capita, according to the county's coroner's office.

"If we stay on this pace, we could quadruple our deaths from last year," Mike Brem, captain of the Montgomery County Sheriff's Office, said.

Fentanyl, a synthetic opioid pain medication responsible for an epidemic of overdose deaths around the U.S., accounts for a significant number of the county's overdose deaths, Brem said.

Fentanyl is 50 times stronger than heroin and 100 times stronger than morphine, according to the U.S. Centers for Disease Control. The agency says illegally manufactured non-pharmaceutical fentanyl, and related overdoses, are a rising problem.

In May, the state of Ohio sued five major drug manufacturers, accusing them of misrepresenting the risks of prescription opioid painkillers.

The county morgue is at "full capacity all the time," Ken Betz, director of the coroner's office, said.

"We can average almost 10 bodies per day in our facility where, historically, five bodies a day was a busy day," Betz said. "Our staff is just plain tired.

"We've never experienced this level of daily drug overdoses in my entire career," he added.

Weidle continues to fight on behalf of Daniel, advocating for stricter laws to curb opioid deaths.

"He always loved to put his arm around you, always had a smile on his face," Weidle said.

"People who looked a little desperate, a little down and out ... he would go friend them. It's something I wish I could do." (Reporting by Linda So; Editing by Melissa Fares and Leslie Adler)

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