Could it have something to do with the Ether? It does have a syndrome. Or maybe the temperatures of some of the components are causing it.
Or possible it has to do with the failure rate. You have lots of accidental byproducts... some that explode. I'm thinking that might cause damage to the wood.
The things I really want are...
1) a percent chance of an ITEMCORPSE (currently not possible)
2) a way to transmit a syndrome through a wound inflicted with a weapon (poison or a new SYN_CONTACT tag that works with metals)
3) "positive" syndromes (i.e. speed boost)
4) a way to get an object to give off a gas without having to boil away (currently not possible)
But alas, these things are a pipe dream until Toady the Great introduces new tokens.
Ether's syndrome doesn't work because it isn't a contaminant (the syndrome isn't bugged, there's just no way for it to be contracted). It was intended to be created in alchemy, made into a weapon, and then make that weapon cause a syndrome when striking certain creatures, but technical limitations prevent this from working in the current version. Courage oak was designed with a similar idea in mind, but was axed for the same reason - I did not leave the syndrome tokens in for that one, though.
All of the exploding byproducts (read: all of the byproducts without exception) do so at room temperature. The syndromes for these work by inhalation, though they vary in effects, name, and severity depending on which one was produced. The syndrome from a minor alchemical failure is not very harmful, while the syndrome from a cataclysmic disaster is, if not immediately lethal, severe enough to warrant some serious health problems. Hazardous radiation is one of these byproducts, which causes nausea and fever (if I remember correctly) and has a small chance of instantaneous death. There are others - some more and some less severe, but I'll leave you to speculation (or just digging through the raws). Transmutation adds another three of these byproducts to the mix.
One of these byproducts, the rare "disastrous conflagration," creates a stone with a boiling point of 12000 (ish) and a fixed temperature of just above that. In theory, it should explode when created, lighting everything flammable within range (i.e. the alchemist) on fire, or at least causing some serious burns. I have not tested this yet, unfortunately. Other possible byproducts are a bit more traditional, following the explode-on-creation-get-inhaled-cause-syndrome model - though some of these new syndromes are quite amusing.
Alchemy is one of the mod's most interesting concepts, in my opinion. I have been able to use it to justify a good number of easter eggs, and even to form a rudimentary sort of "tech tree." I have juggled around the concept of making certain new workshops that require rare alchemy reagents as a form of dwarven "technological advancement." For example, make a megabeast that drops a unique toy as its corpse, and require the toy for an alchemy reaction for an "invention," then require the unique product of that alchemy reaction for construction of a new workshop with unique reactions of its own. As cool as this sounds in concept, I realize that I am treading dangerous ground. I want to be careful not to turn something fun into something frustrating, where people feel that they need to acquire a hard-to-build workshop and that everything that makes that workshop hard to create is a roadblock to their progress rather than a hidden, fun, unique opportunity. All of these ideas are very much within my ability to create, but I would love to get some feedback on this concept before I consider moving something resembling a tech tree forward.