"If people are concerned about nanoplastics in bottled water, it's reasonable to consider alternatives like tap water," Beizhan Yan, an associate research professor of geochemistry at Columbia University and a co-author of the paper told AFP.

But he added: "We do not advise against drinking bottled water when necessary, as the risk of dehydration can outweigh the potential impacts of nanoplastics exposure." nylon 6 fdy yarn for sale

There has been rising global attention in recent years on microplastics, which break off from bigger sources of plastic and are now found everywhere from the polar ice caps to mountain peaks, rippling through ecosystems and finding their way into drinking water and food.

While microplastics are anything under 5 millimeters, nanoplastics are defined as particles below 1 micrometer, or a billionth of a meter -- so small they can pass through the digestive system and lungs, entering the bloodstream directly and from there to organs, including the brain and heart. They can also cross the placenta into the bodies of unborn babies.

The results showed between 110,000 to 370,000 particles per liter, 90 percent of which were nanoplastics while the rest were microplastics.

The most common type was nylon -- which probably comes from plastic filters used to purify the water-- followed by polyethylene terephthalate or PET, which is what bottles are themselves made from, and leaches out when the bottle is squeezed. Other types of plastic enter the water when the cap is opened and closed.

US authorities detained a person near the White House on Monday who crashed a vehicle into an exterior gate of the presidential mansion complex, the Secret Service said.

President Joe Biden was out of town at the time of the incident, and security officials did not say whether it was a traffic accident or intended as an attack.

The crash is believed to have occurred on the northeast side of the complex, given that Guglielmi said to expect "traffic implications" at 15th Street and Pennsylvania Avenue.

The White House has seen a string of high-profile trespassing incidents in recent years, causing sufficient concern to build a higher, tougher metal fence around the iconic mansion's perimeter in 2020.

In 2017 a man who scaled a White House fence traipsed the grounds for more than 16 minutes before he was arrested -- while then-president Donald Trump was inside.

In 2014 while Barack Obama was president, a disturbed US Army veteran jumped the White House fence, sprinted across the lawn and entered the building with a knife in his pocket.

Can a deaf, Native American superhero with a prosthetic leg reinvigorate Disney's Marvel franchise, just weeks after its CEO appeared to criticize his filmmakers for prioritizing messaging over storytelling?

Streaming series "Echo," which launches on Disney+ and Hulu on Tuesday, tells the story of Maya Lopez, a tough former villain who returns from a life of criminality in New York to rediscover her Indigenous roots in her Oklahoma hometown.

Much of the dialogue takes place through sign language, with subtitles, and filmmakers worked closely with Choctaw Nation leaders to create authentic scenes, including a flashback to a sporting festival in pre-European contact America.

Simultaneously, the company has found itself at the heart of the US culture wars, attacked by right-wing commentators and Republican politicians for becoming "too woke" in its storytelling.

Florida Governor Ron DeSantis, a presidential hopeful, has pounced upon complaints about the increasing prevalence of gay and nonbinary characters in Disney films, from "Lightyear" to "Elemental."

At a conference talk in November, Disney CEO Bob Iger said that the company's storytellers had become overly concerned about introducing "positive messages," and had "lost sight of what their number one objective needed to be."

"What I've really tried to do is to return to our roots, which is remember we have to entertain first. It's not about messages," said Iger.

With its diverse casting, "Echo" represents the culmination of a trend for Disney.

Lacina suggested Iger's comments may reflect "frustration" that simply casting non-traditional leads had not automatically brought in vast untapped minority audiences, as hoped.

Still, there is no evidence of a "backlash" from white viewers, who flocked to films like the Oscar-nominated "Black Panther" -- a film singled out for praise by Iger at his November talk for "fostering acceptance."

"And at the end of the day, we're all human beings," said cast member Chaske Spencer, of Lakota Sioux origin.

"What it relates to is emotion... all of us can relate to that."

Companies big and small hosted previews for the press on Monday, with AI a repeated mantra as they pitched products promising better lives.

Televisions will advance to a "smart command hub" connecting appliances, security cameras, and even incorporating thermal scanning for health insights, according to Jessica Boothe, a research director at the Consumer Technology Association that organizes CES.

Volkswagen, meanwhile, presented what it described as the first vehicles built with a chatbot powered by OpenAI's ChatGPT technology.

The "Cerence Chat Pro" digital assistant made in a partnership with Cerence Inc. will be standard in many Volkswagen vehicles starting in the second quarter of this year, according to the car maker.

Nvidia, whose graphics chips are coveted for their ability to handle the intense computing demands of AI, took CES as an opportunity to announce new chips for gamers and creators.

Apple, which is not at CES, said Monday that it will release its highly anticipated Vision Pro mixed reality headset in the United States on February 2, in its first major product release since the Apple Watch in 2015.

Announced in June, the Vision Pro will cost a hefty $3,499 before tax, more than double the price of Meta's top-of-the-range Quest Pro headset.

- Year of AI at CES -

CES exhibitor and attendee numbers have jumped each year since the Covid-19 pandemic caused it to be an online-only event in 2021.

While the show is increasingly a showcase for startups, big brands such as Amazon, Google, Intel, Netflix, Samsung, Sony and TikTok will also be there.

Analysts expect it to be the year of AI when it comes to product pitches at CES.

Models on which AI is built have improved dramatically since last year's CES and the debut of OpenAI's ChatGPT, and they are being applied in meaningful ways for consumers, according to Greengart.

Ending Friday, CES is expected to see strong themes of AI-infused health, cars, beauty, entertainment and sustainability.