Iraqi man detained
diphenylamine chlorarsine (di·phen·yl·amine chlor·ar·sine) a toxic compound used as a gas in war and, as a compound with tear gas, in riot control; also used in some wood preserving solutions. It irritates the skin and respiratory tract and also causes nausea, vomiting, depression, and weakness. Called also adamsite and phenarsazine chloride. Symbol DM.
It is listed as an "irritating material" in a hazardous materials list.
They're still not sure about the hydrazine. My gut call on this is a one-man wannabe sympathetic to Iraq. Although I'm no expert, I'd bet it wouldn't take that much to get your hands on this kind of stuff. Note the tear gas reference.