I recently flew with Delta Airlines from Toronto to San Jose, Costa Rica. The flight went via Atlanta. I was planning on bringing photo chemistry to Costa Rica, and I´ll tell you, trying to get information on weather or not it was allowed was a joke.
I spoke to Delta Airlines "Dangerous Goods Desk" - they could not give a definite yes or no. I spoke to the TSA, and the best I got out of them was that they "didn´t think it would be a problem." The FAA was equally useless. None of these agencies could give me a definite answer. I eventually spoke with a Delta representative who declared that it was ‘not in the list of prohibited items, so as long as they’re in new bottles it won’t be a problem’.
I went with that information. I ziploc bagged everything, and chucked it in my backpack. I had HC110, Rodinal, Fix, Stop and Hypo Clear. It made it through without anyone saying anything. My bag did get lost for a week, which has more to do with Delta being a rubbish airline than anything else. But that´s another story.
The link that copake ham provided is a good start. I looked at it many times. It doesn´t specify photo chemistry, but there are certainly similar things (bleaches, etc..) that are not allowed. I have a feeling that if they wanted to kick up a fuss, they certainly could. It´s a bit of a crap shoot, I´m afraid.
A colleague who does a lot of work abroad says that she always brings powder chemistry, as opposed to liquid, and has never had any problems. She has been doing that for the last 20 years or so. Shame I don´t use any powder developers!
Good luck!