The researchers then analyzed air quality near each printer after it had printed one page, and used this data to categorize printers by the amount of particles released. Particle levels rose as soon as the printer started.
The scientists then chose three printers -- a low, medium and high emitter -- for further studies inside a closed chamber.
A newer toner cartridge released more particles than an older cartridge, the scientists found. Printers also emitted more particles when printing toner-heavy documents such as graphics.
The study primarily considered particles less than a micrometer in size, but the authors noted that even the printers labeled as non-emitters might be releasing larger particles, which are also potentially hazardous to human health.
Other studies have found printers to emit volatile organic compounds and ozone as well as toner particles.
Morawska recommends that homes and offices have adequate ventilation to ensure that the printer particles are dispersed.
amber.dance@latimes.com
