A study by an Australian scientist shows that laser printers pollute the air with microscopic particles potentially as harmful as cigarette smoke. Lidia Morawska, a Queensland University of Technology professor, made the discovery when studying office air filtration and ventilation systems.

A study led by the physics professor found many laser printers emit clouds of ultra-fine particles that she compared with cigarette smoke and motor vehicle emissions. “They are so small you can’t see them.”

Although her team has yet to analyse their chemistry, she warned that such small particles “can get deep into the lungs”, leading to respiratory and cardiovascular problems. Some particles were potential carcinogens.

Printer manufacturer HP disputes the findings. In the meantime, y’all might want to move that printer away from your desk (after you print out the study, of course).