Do humidifiers make you sick?

Around this time last year began my obsession with “Crane Adorable” humidifiers.  They come in a selection of (self-described) adorable animal shapes (duck, cow, panda, pig… you get the idea) and spit out 2 gallons of cool mist per day.  With my daughter scratching holes in her arms from dry skin, I bought one for each snerd (penguin and elephant), my nephew (frog) and as a baby shower gift (dog).

Then my mom sees them, gasps, and worries I’m making the snerds sick running a humidifier in their rooms.  This isn’t the first time she’s accused me of poisoning my kids (the last was when she found non-organic peanut butter in my pantry– you know how harmful that is?!?), but a  little research revealed that others worry about humidifiers too.

Apparently, humidifiers, if used “incorrectly” can grow mold, which they spew all over.  Or running them too much causes mold to grow in your house from “excessive humidity”.  But, first, how can you use an “adorable” plastic penguin incorrectly when all it has is an on/off switch? (not even a filter).  And in the summer our house reaches 100% relative humidity, how can a humidifier create more moisture than that?

So, in preparation for using our penguin and elephant again, I gave them a good scrub and checked for mold (none is visible).  I did more research but can’t come up with anything but concerns about mold.  So is this really a problem?–even if I change the tank every couple of days and give it a good rinse?   And, if so,what do you suggest as an alternative? (my mom advocates hanging a wet towel, but that leaves a puddle in the carpet, which can’t be good either, and isn’t nearly as fun for my kids).  Thoughts?