In the column Do photocopy machines emit radiation?, from 1977, it’s said that photocopiers are essentially harmless. This isn’t true.
Photocopiers emit large amounts of ozone – in fact, you can often smell the ozone if the photocopier is in a small room, especially if it contains several machines. Ozone is produced by electrical discharge through air; it’s the smell associated with electrical arcs and badly maintained motors. It’s also highly toxic. Ozone irritates the eyes, the respiratory system, the mouth, and can cause itching. It can cause headaches, nausea and premature aging of the skin. Asthma is also aggravated by ozone in some people. Ozone is a major hazard in small, poorly ventilated photocopy rooms. If you work somewhere where you notice a strange smell around the photocopiers, you’re being exposed to dangerous levels of ozone.
Some elements of toner are volatile organic compounds (VOCs), which persist in the air for long periods of time. Some of the VOCs associated with photocopiers are benzene and decane (carcinogens), toluene (which can cause irritation and drowsiness), and xylene (which can cause kidney damage).
Areas near photocopiers which are not adequately ventilated can contain dangerous levels of carbon monoxide, and poorly maintained machines can produce nitrogen oxide, a gas that produces similar effects to carbon monoxide and also affects the central nervous system in the presence of ozone.
The secretary’s warning about “[ruining one’s] eyes by exposing them to deadly rays” has a kernel of truth, though it’s exaggerated. The bright lamps on photocopiers emit more than harmless visible-wavelength radiation that causes effects no worse than visual afterimages. They also emit UV radiation, and that can cause eye irritation and possibly even eye damage, not to mention wrinkles.
You can read more about the hazards of photocopiers here and here. An MSDS for ozone is here.
The hazards associated with photocopiers also apply to laser printers. I’m not sure how much of a threat they really pose to office workers, but there’s probably some cause for concern if you can smell ozone in an office or photocopier room. (I can’t really describe the smell – I actually learned the smell as the smell of a small room that contained several copiers. It had several ventilators, but they didn’t seem to be enough. This was in a lab building with hundreds of fume hoods, where most of the people making photocopiers knew the smell of ozone and knew its dangers. I imagine that most office buildings have little if any ventilation for their photocopier rooms.)