Ben Lecomte, 51, will swim through shark territory and the Great Pacific Garbage Patch in pursuit of a world record and groundbreaking research.

After swimming across the Atlantic Ocean in 1998, Ben Lecomte told Oprah, “never again.” But alas, the ocean is an alluring place.

The 51-year-old French-born Texan kicked off the shore in Choshi, Japan on June 5, and doesn’t plan to set foot on land again until he reaches San Francisco in November. He’ll swim eight hours a day until he’s completed all 5,500 miles of the Pacific Ocean.

Lecomte is attempting “The Longest Swim” to draw attention to plastic pollution in the North Pacific Gyre, also known as the Great Pacific Garbage Patch. “I’m using this swim as a mode of expression, to invite people to discover this mysterious world, show its beauty but also its fragility,” he told Power & Motoryacht.

The Great Pacific Garbage Patch is a collection of waste twice the size of Texas that floats in a gyre where the currents converge between California and Hawaii. There are an estimated 250 pieces of plastic for each person in the world, the majority of which are microplastics, or pieces smaller than a pencil eraser.

Lecomte is accompanied by a Challenge 67 support yacht, Discoverer, which also serves as a research vessel. In collaboration with 27 scientific institutions including NASA and Woods Hole Oceanographic Institution, the eight-person crew runs tests and collects hundreds of samples that comprise the most in-depth study of the Pacific Ocean to date.

The study will help scientists understand plastic pollution, human endurance and the extent of radiation contamination from the 2011 Fukushima nuclear disaster.

Lecomte’s father taught him how to swim when he was 5 years old. “We took a big wave, and I ended up upside down with sand in my mouth and a big smile on my face,” he said in an email. “I fell in love with the ocean that day.”

Now, as he navigates the vast, disorienting Pacific Ocean, the adventure is as much a psychological challenge as a physical one.

The route includes swimming through the migration area of Great White Sharks. When he swam the Atlantic in 1998, a shark followed him for five days. This time, he’s wearing a shark bracelet to repel unwelcome advances.

“I used to ride a motorcycle in Paris, and I can guarantee you there’s much more risk in doing that than swimming in the ocean,” he told the Washington Post.

The swimmer stays on course with the help of a guide dinghy, which can also assist in case of emergency. When he’s done swimming for the day, he rests aboard Discoverer, which drops a sea anchor to remain positioned for the start of the next day’s swim.

The swim is the culmination of seven years of planning. Despite being set back a few days by a storm early in the journey, Lecomte is pressing onward. “There is a long list of forces outside of my control that I can’t change,” he wrote on his blog. “[The] only thing I can change is the way I think about them and react.”

Despite all these mysterious forces, or perhaps because of them, Lecomte jumps in the frigid water each morning. “I have a very weird and strong connection with this blue world,” he says, “and I hope this swim will invite people to question their own relationship with the ocean.”