Jury still out on laser printer pollution

Evidence that particle emissions from laser printers are harmful remains elusive, but a new report published last month suggests some devices at least have the potential to pollute offices more than others.

Testing conducted by the International Laboratory for Air Quality and Health at the Queensland University of Technology (QUT) in Australia examined a range of printers from four manufacturers: HP, Mita, Ricoh and Toshiba.

The tests found that 12 of the 13 devices that emitted the highest level of particles into the atmosphere were HP LaserJet models, with the other a Toshiba. The QUT acknowledged that the printer test base was limited, however, and the toxicity of the emissions not defined, making an accurate conclusion difficult.

"While a more comprehensive study is still required – to provide a better database of printer emission rates, as well as their chemical characteristics – the results from this study imply that sub-micrometer particle concentration levels in an office can be reduced by a proper choice of the printers," the report stated.

Though the topic of laser printer pollution has been debated for many years, the question of whether printer particle emissions are harmful remains unanswered.

Mike Dinsdale, head of communications and corporate social responsibility (CSR) at printer manufacturer Brother UK, pointed out that QUT research was by no means the first to identify laser printers as a possible source of pollution in offices. But it is the first to be conducted by atmospheric experts and is therefore significant.

"What we are talking about is airborne dust that has a number of possible impacts. If the dust is very small, it can penetrate the pores and be a source of irritation to the skin, eyes and nose, and maybe have an impact on asthma sufferers as well," Dinsdale said.

Breathing in the toner used in laser printers, and the chemicals that it includes, represents the biggest fear for workers, but other substances may be to blame.

"It is not just toner, and the report does not identify the size and type of particles emitted, but I suspect it is primarily paper dust, which varies according to the paper type, size and the guillotine," explained Dinsdale.

The QUT survey did suggest that particle emissions were slightly higher when printing graphics, however, which require more dense toner coverage, and also when the toner cartridge was new.

HP was unavailable for comment but did release a statement in response to the QUT’s findings. The company said it conducts its own printer emission tests and has engaged with independent organisations in the US and Germany to do the same.

"Testing of ultrafine particles (UFPs) is a very new scientific discipline. There are no indications that ultrafine particle emissions from laser printing systems are associated with special health risks," the statement said. " Currently, the nature and chemical composition of such particles – whether from a laser printer or from a toaster – cannot be accurately characterised by analytical technology."