But what he found when he made it to the bottom of the Mariana Trench, the deepest marine environment, surprised even him.
There, floating in the pitch-black abyss 36,000 feet below the surface, were pieces of plastic — including plastic bags and food wrappers, according to the BBC.
Vescovo also found animals in the trench, some of which were collected for further analysis. Scientists will open up their guts to see if they had consumed ocean plastic.
"It was very disappointing to see obvious human contamination of the deepest point in the ocean," Vescovo told the New York Times.
The trip was made possible by a vessel created by Triton Submarines that can withstand extreme amounts of pressure. If a person were transported to the Mariana Trench, which is located in the western Pacific Ocean, the pressure, equivalent to 50 jumbo jets stacked on top of each other, would crush them.
Vescovo plans to take the submarine to the Molloy Deep, the deepest section of the Arctic Ocean, in August, which will be the final challenge of his gauntlet.
The latest dive was intended to demonstrate the limits of human endurance and ingenuity, only the third time a human had ever dove to such depths, but it’s become overshadowed by the pervasive nature of plastic pollution.
This isn’t the first time that scientists have found plastic in the Mariana Trench either.
A study published earlier this year found that every animal extracted from the trench had consumed microplastics. Another group of researchers recorded a plastic bag in the Mariana Trench in 2018.
Other studies have shown how plastic has contaminated other remote environments. Scientists have found microplastic encased in Arctic Ice and blanketing the Pyrenees Mountains.
Even Mountain Everest holds more than 22,000 pounds of waste.
Scientists are beginning to suss out the health consequences of plastic waste, but preliminary research on animals shows dires results. Turtles, for example, become 20% more likely to die after ingesting a single piece of plastic, and whales have been found emaciated and vomiting blood with dozens of pounds of plastic waste in their guts.
As awareness of plastic’s negative impact spreads, countries are beginning to take action.
More than 60 countries have banned certain types of plastic, and the United Nations recently oversaw the formation of a global pact meant to fight ocean plastic waste.
The discovery of more plastic waste in the Mariana Trench could spur even greater efforts toward sustainability.
