Upvote:12
Pressure
Luggage compartments in commercial airlines are pressurized. Review the question and answer in this Aviation:SE question.
While the internal pressure is not maintained at sea level (it's usually maintained at the equivalent of an elevation of 8000' or 2438 meters above sea level), the pressure drop will only be noticeable if the object itself — such as a bag of potato chips — is itself sealed. Non-sealed things like a printer cartridge are thus unlikely to spill. If you're nervous about it, wrap the cartridge in a plastic bag with a few pinholes to allow air to move in and out.
Carry-On Suitability
Whether you can bring a laser printer cartridge in your carry-on luggage will depend upon the assessment of whatever agency is doing the security evaluation at your departure airport. In the US, that's the Transportation Security Administration. At some US airports, private contractors do this work; see, for example, San Francisco International.
You didn't specify your itinerary, so I do not not know where you're boarding and, therefore, who or what entity is conducting the pre-boarding security inspection. This answer, then, presumes that it's either the TSA, or another organization or government which applies similar standards.
TSA maintains a What Can I Bring? website. Searching on that page for "laser printer," "printer cartridge," or "laser printer cartridge" returns nothing. Searching for "printer"," however, returns information that carrying or checking a printer is OK. Thus, either of these objects (the printer, the cartridge, or the printer with the cartridge installed) may be taken with you into the cabin as carry-on baggage, or checked-in as hold luggage.
Two additional notes: checked luggage is more subject to theft and pilferage and physical damage than carry-on baggage. Checked luggage is often thrown into piles in loading and unloading; make sure that whatever you check is suitably packed to resist impact and crushing. Further, whatever you carry or check must meet the airline's limits about weight and size.
Your Choice
Whether you carry or check or plan to replace the cartridge will depend upon the cartridge's cost and availability at your destination, as well as your personal assessment of the risk of loss attendant upon taking it with you compared to the additional cost of buying it again.
Upvote:13
Reviewing the safety data sheet of a copier toner cartridge we find:
it is not a dangerous good as far as the IATA DGR is concerned -- or any other relevant regulations for that matter -- so checking it in is completely fine. You can see the same for a HP Laserjet cartridge or any other similar product: "Not a regulated article under DOT, IATA, ADR, or RID"