Research finds potentially toxic chemicals used in smartphones and TVs escaping into environment

An international research team is sounding the alarm about potentially harmful chemicals — used to manufacture screens for devices like smartphones and TVs — being found in homes and other buildings even when the devices aren't present.

In a paper published this month in the Proceedings of the National Academy of Sciences, researchers found chemicals called liquid crystal monomers in household dust samples collected in China.

That's problematic because the chemicals are supposed to stay contained within the screens.

"They're supposedly sealed in the screens when they're made, but obviously they do come out," said Prof. John Giesy, a Canada Research Chair in Environmental Toxicology at the University of Saskatchewan.

"The fact that we found them in people's homes indicates that they are being released during use of the products."

It's not clear how the chemicals are escaping the screens. While they can leak out if the screen breaks, he's not sure how smaller quantities escape.

Researchers tested dust from seven different buildings in China, ranging from a canteen to a student dormitory to a personal residence. Nearly half of the 53 samples tested positive for the chemicals.

The paper looked at over 300 different liquid crystal monomers in use right now and studied their potential to be released and any harmful effects. Nearly 100 of the chemicals were found to be potentially toxic.

More research needed

The paper includes significant findings that should trigger more research, according to George Cobb, chair of the department of environmental science at Baylor University in Waco, Texas. Cobb, who wasn't part of this study, has done dust studies in the past to test for other chemicals. 

He said he is planning to send some of his samples to Giesy to test for liquid crystal monomers.

Cobb said liquid crystal monomers have flown under the radar of regulators because they were considered to be contained, but this research proves otherwise.

"These compounds, because they're embedded in the screens for devices, the exposures are considered to be relatively low, at this point, and that's why Dr. Giesy's information is so important," he said.

"Now it shows these exposures are in our homes ... and up the priority to getting these things assessed in a regulatory fashion."

Cobb said it is "essential" to know which compounds are present and the concentrations we may be exposed to. He said he isn't waving a red flag at this point but that studies like these show there is more information needed to address potential human health risks. 

Joanne Fedyk, executive director of the Saskatchewan Waste Reduction Council, agreed that there is no cause for alarm yet, but that more needs to be done to determine where we are vulnerable.

Her list of questions is long. 

"I want to know what the chemicals are, in what concentrations, where they found them, how they got there, whether this is something we need to be worried about just yet, how can we protect ourselves, all those sorts of things," she said. 

Giesy said the belief that the chemicals were sealed in the screens has led to a general lack of awareness.

"Right now, there are no standards for any of these chemicals, so we had to apply what we call ultra-high resolution mass spectrometry to even identify them," he said.

"Hopefully, people doing research will see it and get interested."

Fedyk said the research is an important start — pointing to examples when heavy metals have been phased out of devices after being deemed unsafe to humans.

The research got its start when Giesy was doing work on e-waste recycling in China. He quickly realized there had been little research into the chemicals that make up these screens, so the team started smashing up phones and analyzing what the screens contain.

Cobb suggested exploring whether the existence of these chemicals in buildings in China is connected to the proximity to manufacturing plants or the devices themselves.

Concerning chemicals

Giesy said some of the chemicals' properties are concerning because they have the potential to accumulate in animals, resist breaking down in the environment and travel long distances through the atmosphere.

Lab testing showed some of the chemicals affect animals' ability to digest nutrients and cause gallbladder and thyroid malfunctions, similar to dioxins and flame retardants.

Some of the chemicals are also similar to other compounds that have been banned in Canada. Giesy expressed concern about the sheer number of liquid crystal display screens being produced. Approximately 198 million square metres worth of the screens were produced last year, according to the study.

Giesy has reached out to researchers at Environment and Climate Change Canada, along with professors in China and the United States, to help work on the research.

Previously, he was the first researcher to identify perflourinated compounds (PFCs) spreading through the environment. His research led to a worldwide ban on the chemicals.