Authorities investigate whether Martha Nolan-O’Slatarra died of ‘designer drug’ overdose

Long Island prosecutors are probing whether “designer drugs” played a role in the mysterious Montauk Yacht Club death of Irish fashion designer Martha Nolan-O’Slatarra, Suffolk County DA Ray Tierney said Tuesday.

Investigators have not yet determined what killed the 33-year-old woman, who was found dead on a boat at the upscale club Aug. 5, but sources have said authorities suspect an accidental overdose.

Officials are awaiting more autopsy results before concluding the probe, Tierney told The Post.

“Specifically, we’re talking about primarily the toxicology — the official final toxicology report,” the DA said.

“In our society right now, the way we’ve evolved with these designer drugs, all these substances that are created in a lab, you want to be extra careful that whatever testing you’ve done is comprehensive and complete before you` make any findings in the case.

“Oftentimes it’s not just one substance,” he said.

“What you do is you test for heroin, cocaine and fentanyl, right?” Tierney said. “Now you want to test for zylazine, you want to test for nylazine. You want to test for some obvious other substances.

“You want to make sure it’s as comprehensive as possible, just because you may get a result on one substance that doesn’t preclude the possibility that another substance was used as well,” he said.

Nolan-O’Slatarra, who migrated to the US from Ireland in 2018, co-owned swimwear company East x East and summered in the Hamptons, where she was featured in pop-up fashion shows.

Police responding to a 911 call found her on a boat named “Ripple” at the club, where she was pronounced dead after CPR attempts by bystanders failed to revive her.

There have been no arrests in the case, nor have prosecutors suggested foul play.

The boat is one of at least two Grateful Dead-themed crafts owned by insurance mogul Christopher Durnan, sources have told The Post.

Durnan, 60, a familiar figure at the yacht club, owns the Durnan Group in Rockville Center. His business manages the “largest, most successful Workers Compensation Safety Group for Real Estate,” according to The Empire State Marine Trades Association.

His second boat, “Hell in a Bucket,” was docked next to “Ripple.”

A funeral for the designer is scheduled for Wednesday in her hometown of Carlow, a small Irish village about 50 miles from Dublin.

Studious and driven to succeed, the late designer earned a bachelor’s degree in business administration and management from University College in Dublin and went on to earn a master’s degree in digital marketing at the UCD Michael Smurfit Graduate School of Business, also in Dublin, in 2014.

Here is the latest on the dead body found on a Montauk Yacht Club boat

“I always knew I wanted to be successful, that I was money-driven, business-driven, and that fashion is a tough industry and it would be a slow road,” she told the Independent last year.

Her funeral will be at 10 a.m. at the Cathedral of the Assumption in the tiny Irish town of Carlow, followed by burial at the local St. Mary’s Cemetery, the Irish Independent reported.