If you work in an office, there could be a health risk lurking just outside your cubicle. Some laser printers release tiny particles into the air that can enter the lungs and cause health problems, according to an Australian study.

When a toner cartridge begins to run out, you may have gently shaken the cartridge to evenly spread the remaining toner.

Physicist Lydia Morawska and her colleagues at the Queensland University of Technology, at Brisbane, believe tiny particles of that toner escape from the cartridge during ordinary use, especially when the cartridge is shaken.

They say the problem can be mitigated by placing printers in a well-ventilated area so the particles can escape. Printers should not be placed in small, closed rooms, they say.

The researchers said they investigated 62 different laser printers and classified 17 of them as high emitters. They characterized the worst of the 17 as releasing particles at a rate comparable to emissions from cigarette smoke.

The study included models sold under the Canon, HP, Ricoh and Toshiba brand names. The report was published in the latest issue of Environmental Science and Technology.


Low-Level Emitter

Middle-Level Emitter

High-Level Emitter

HP Color LaserJet 4550DN (1)

Canon IRC6800 (1)

HP LaserJet 1020 (1)

HP Color LaserJet 4650dn (1)

HP Color LaserJet 8500DN (1)

HP LaserJet 5M (3)

HP LaserJet 4200dtn (1)

HP Color LaserJet 5550dtn (1)

HP LaserJet 2200DN (1)

HP LaserJet


HP Color LaserJet 8550N

HP LaserJet 2300dtn (1)

9000dn (1)



HP LaserJet 4 plus (1)



HP LaserJet 1320N (1)

HP LaserJet 4000N (1)

CL3000DN (1)


HP LaserJet 1320n (1)

HP LaserJet 4000TN (1)



HP LaserJet 2420dn (1)

HP LaserJet 4050N (2)



HP LaserJet 4200dtna (1)

HP LaserJet 4050TN (6)



HP LaserJet 4250n (old)

HP LaserJet 4si (1)




HP LaserJet 5(b) (1)



HP LaserJet 4250n (new)

HP LaserJet 5000n (1)




HP LaserJet 5100tn (2)



HP LaserJet 5(a) (1)

HP LaserJet 5N (2)



HP LaserJet 8000DNa (1)

HP LaserJet 5si (1)



HP LaserJet 8150N (1)

HP LaserJet 5si/NX (1)



TOSHIBA Studio 450 (1)

HP LaserJet 8000DN (2)




HP LaserJet 8150DN (3)




Mita DC 4060 (photo copy) (1)




RICOH Aficio 2022 (1)




RICOH Aficio 3045 (1)




RICOH Aficio 3245C (3)




RICOH Aficio CC3000DN (1)




TOSHIBA Studio 350 (1)




a Possible high emitter.
Source: Environmental Science and Technology

Despite the presence of laser printers in nearly every office, there hasn't been much research into their effect on health.

Ten years ago, the Environmental Protection Aency (EPA) evaluated printers and photocopiers, but these data are now "interesting historical information," comments Charles Weschler of the University of Medicine and Dentistry of New Jersey.

Printers have changed a lot since then: most have shifted to ink jets and other technology, and dramatic improvements have changed cartridges and even "the nature of toner itself," Weschler says. These new data are only the first steps in getting modern assessments of exposure to printer particulate matter, he says.