March 20 (UPI) -- Simply opening a plastic package can introduce microplastics into the atmosphere and be ingested or inhaled, a new study indicates.
Chinese scientists, funded by the Australian environmental research company CRC CARE, studied the travel of microplastics -- plastic pieces less than 0.2 millimeters in length -- after plastic bags of food and plastic drink bottles are opened, as well as plastic sealing tape after a package is opened.
The researchers found that fragments of 10 to 30 nanograms, or 0.0001 to 0.00003 milligrams, of plastic remain in the atmosphere through cutting or twisting larger pieces of plastic, according to the study, published this week in the journal Scientific Reports.
While microplastics are normally associated with pollution in the form of bulk waste made of chemicals that have proven slow to break down, the researchers noted that everyday human interaction with plastic could be additional sources of pollution.
Simply tearing open a bag of snacks releases nearly invisible plastic fragments into the air, with the amount dependent on the stiffness, thickness and density of the bag.
"This finding sends an important warning, that we must be careful when opening plastic packaging, if we are concerned about microplastics and care about reducing microplastics contamination," the study's abstract states.
The risk and toxicity to humans was not resolved by the study, researchers say.