Hey guys,
I work at a testing facility, we test and verify products put simply ..
A few years ago we did some testing on a device an electronic device that could essentially sniff drugs .. idk if these are at airports or if the will be but they exist
It all depends on the size of the detector and what it will be used for. At one point, some LEO's were using a specially built flashlight that sampled the air and could detect alcohol. Since it's normal for cops to put a flashlight in peoples faces, it was pretty sly for night stops.
They basically used it as PC to give you a field sobriety test and/or real brethylyzer.
I think it's use was struck down as being an unwarranted search. Right now, it's illegal for the police to detain you while they call for a drug sniffing dog if they have no pc to search. A lot of people don't know that and stay essentially voluntarily. That's why it's important to ask if you are being detained or if you are free to go. They need cause to detain you beyond a license check.
So if they had a portable sniffer, they would likely need cause to use it. Just like they would for a dog, but they wouldn't have to detain you to wait for it.
My guess is it would be more useful at border crossings and container yards.
But to the OP's question, in us airports at least there is no active search for cannabis. I'm not recommending flying dirty, but lots of people do, especially with vape pens.
Seeds would almost never be detected unless you had a LOT of them. It's not what the screeners are looking for. Even when my backpack gets hand screened, they wouldn't find seeds if they were there. That isn't what they are looking for. They are looking for weapons, or anything that could be used as one.