Laser printers as unhealthy as smoking

Laser printers could pose health risks on par with smoking because of particles they release, according to a study by Australian researchers.

Scientists at the International Laboratory for Air Quality and Health in Australia tested emissions from 62 laser printers, looking for particles less than a micrometer wide. They found that 27% emitted hazardous levels of particles, which are so fine they are not readily filtered by the lungs. Some produced the same amount of particulate pollution that a smoker would generate.

"Particles have been shown beyond any doubt to be a health hazard," said study author Lidia Morawska, a physicist at Brisbane's Queensland University of Technology. She explained that inhaling such fine particles can cause respiratory irritation, cardiovascular problems and cancer.

But not all printers are a threat, the study said. Eight HP LaserJet 4050 series and four Ricoh Aficio models gave off no dangerous emissions at all. On the other hand some models - when printing - increased the number of particles in the air more than tenfold, according to the report published in the Environmental Science and Technology journal.

Morawska claimed the researchers had set out to test how outdoor pollution affects the office environment and expected indoor levels to be much lower. But instead they found that during office hours indoor pollutants were, at worse, three times as high as outdoors.

But she stressed more research is needed to prove whether or not there is a health risk. Her tests took no account of variables such as printer age or cartridge type that could affect emission levels. Morawska noted that when testing apparently identical printers one emitted no particles while the other generated high levels.