I have something on my mind. Seems like I've seen a lot of writing about knitters liking acrylic yarns for baby items (including a recent review from Knitter's Review). This scares me tremendously. Now, I'm not getting on my fiber-snob high horse here, I'm trying to educate.
Washability for babies and children is very important. In today's knitting world, there are many, many natural fibers that are washable and soft (cotton, linen with washing, hemp with washing) and many more that are treated to be washable (any superwash wool). Sure, some are expensive, but with the internet, anyone can find a deal. Let's compare: Acrylic Yarn at Joann's and Superwash Wool at Elann.com. There may not be as great a selection, but some further searching will yield this from Webs. In fact, if you will notice, some of the acrylic yarns are downright expensive. $7.99 for 33 yards of a bulky acrylic is not that great of a deal.
Again, I'm not being snobbish. There's a larger issue than whether or not I like acrylic yarns. The issue is flammability. Or, rather, meltability.
Acrylic yarn, if ignited, will melt. It is not fire-retardant by any means, though it may take longer to actually ignite. Baby clothes and other baby items that are not fire-retardant are treated to be so or they come with a warning. I'm not saying that we should put a warning on all acrylic yarn, but I do want people to think about it. I will note that cotton and linen both ignite easily. Melted acrylic can cause severe burns and might drip onto other surfaces.
I don't expect knitters to know that wool is self-extinguishing and therefore a great material for babies (try Lorna's Laces Shepherd yarns), but I do think that we should learn a little more about the fibers we use. We choose a particular yarn for so many reasons. Shouldn't the safety of our little ones be an important factor. If it isn't a factor, or if knitters aren't as worried about fire as I am,* then I say stay away from acrylic because it is sticky and shiny in a bad way, or choose it because you have a good reason (like it was given to you as a gift and you must use it). I'm all for a little microfiber** to add resiliency and bounce (to adult garments), but I won't use any 100% microfiber.
The more I research, the more I'll hesitate before using cotton or other plant fiber for baby items. For adults, or for babies that are not born to smokers, I'll use cotton and the like along with superwash wool.
Of course, if there is a fire, there's more than just melting baby blankets to think of (as a friend pointed out to me today), and I may just be overreacting.
*Until recently I could not sleep with the bedroom door open, even just a little. I really took that firefighter demonstration in fourth grade seriously.
**I just read on Wikipedia that microfiber does not come from a renewable source, so I will not try to avoid it as much as possible. See what a little research will bring?