3D printers produce particles that can negatively affect air quality indoors, make the air toxic, and potentially harm respiratory health.

"Some people call this higher concentration of pollutants around the human body the personal cloud... we call it the 'Pig-Pen Effect.'"

The developers of a nonthermal plasma method for killing airborne viruses hope it can one day replace the surgical mask.

"We're basically saying: 'Hold on, don't worry. Things might look like they're getting worse, in some places, but overall they should get better.'"

Diesel exhaust from heavy truck traffic contributes to air pollution, which has been linked to asthma, lung diseases, and heart disease.