I worked as a furniture maker for about five years using a lot of dust causing machinery. The dust was particularly nasty as the wood we most commonly used was Kwila - a very hard wood with a very dark colour. Despite extraction systems and dust masks my mucus always contained obvious remnants of the wood at the end of the day. This was a big reason why I got out of the industry (and the fact that Vietnamese and Chinese workers came A LOT cheaper). The only other symptom I noticed, apart of the discoloured mucus, was frequent wheezing.
I haven't noticed any continuing symptoms, but I have been treating my lungs completely differently in the two years since I left the industry and found Freediving. I am hoping I have managed to expel all that crap now but who knows? Anyone think I may have sustained permanent loss of lung function? I haven't had any problems with diving or apnea activities so hopefully not

.
Hope you manage to avoid any further problems SanderP

. Remember next time your working with wood - use a mask and even a household vacuum cleaner can work wonders when positioned by the source of the dust (eg. sander, drill, saw). Most modern power tools that create a lot of dust even have a place where you can attach the vacuum and suck the dust away at the source.
(I wish I had a sauna

)