Quite a few months ago, I mentioned a test I thought I might run. I didn't start it at the time because it was winter and my assistants for this particular test tend to be sluggish when it's cold out. Then I forgot about it for a while.
For those who followed the link above, yes, I'm talking about that test.
Meet my lovely assistants, who will be doing the actual work of the biodegradation test! It's summer now, and they're happily eating through my kitchen scraps.
Before I give them one (new) biodegradable J-cloth, however, there was something I had to check, based on the product description: these biodegradable cloths were also antibacterial!
The reason I had to check is that while bacteria and invertebrates are very different, they may have some common responses to toxicity that, say, warm-blooded creatures won't.
A little bit of digging tells me that the cloths use triclosan, a common antibacterial agent.
Fortunately, Environment Canada has done an assessment on triclosan including looking at studies of its effect on earthworms, in particular my little friends Eisenia foetida, and they found that the first effects (not deaths, just effects) showed up at levels higher than one finds in soil. Since the listed value for no effect at all was > 50 mg/kg, I think my assistants will be safe; the amount of triclosan on a single j-cloth is probably substantially less than 50mg, and I definitely have substantially more than 1kg of, er, stuff in the compost bin.
Let the experiment begin!