I have noticed tiny crawling insects in my bathroom of late. They do not fly, and they are not in any particular spot. Instead, I just spot one, or at most 2, here and there. Usually, they are just lying still in the tile grout, in isolated spots. I have also sometimes seen one in the sink or on a window sill. Looking closely around the bathroom, I tend to spot 2-3 a day at the moment, usually in the morning. I was spotting 7-8 a day when I first noticed this a week or 2 ago. They are really tiny - they just look like specks in the tile grout. I have uploaded pictures here http://s1132.photobucket.com/albums/m563/fizzy_ie/Misc/ showing the size relative to the 14cm square tiles and I have also attached some close up shots where I tried to zoom in on them. They are usually lying still, or sometimes crawling quite slowly. They often start to move when you go near them but they are easily caught. The bathroom does have ventilation issues. It's an apartment and despite the bathroom having a large window and extraction fan, light mould/black specks build up over time on parts of the ceiling and on the tile grout in some parts. However, the problem has not worsened in the 4 years I have been there and I have only noticed these crawlies recently, although they are very hard to spot on the tile grout so I can't be sure exactly when the issue started. I tend to see them most often in the dry parts of the bathroom (the wall opposite the shower that never gets wet). From doing some research here and on other sites, I think they might be book lice / psocids but I really have no idea. If anyone could shed any light on how I could get rid of this problem, I would really appreciate it. Thanks.