Tiny bits of toner wafting from laser printers can't be blamed for polluting indoor air, according to research released this week.
But researchers from that school and the Fraunhofer Wilhelm Klauditz Institute in Germany have found no evidence to support that claim, after examining the makeup of chemicals released from laser printers.
They determined that such airborne materials include paraffins and silicon oils that evaporate when a printer's fixing unit, which attaches dry toner ink to paper, reaches temperatures as high as 428 degrees Fahrenheit.
"One essential property of these ultra-fine particles is their volatility, which indicates that we are not looking at toner dust," said Tunga Salthammer, a professor who worked on the study, in a statement.
The study did not describe how breathing in the ultra-fine chemicals could affect human health. However, volatile organic compounds are a major source of pollution indoors, where they are found in the air at levels up to 10 times higher than outdoors, according to the Environmental Protection Agency.
The nonprofit GreenGuard Environmental Institute offers a directory of electronics that emit relatively few of such chemicals, but that does not include printers. Last year's Australian study identified printer models with the highest emissions.
Add-on filters would do little to prevent printer emissions, according to researchers participating in the latest study, who noted that volatile organic substances are also released into the air from other household activities, such as toasting bread and cooking.
Printer makers belonging to the German Association for Information Technology partly funded the research.
German lawmakers plan to talk about the potential for laser printers to cause health problems at a meeting in January , according to Heise Online.