Carpet beetles vs. sweaters

September 8, 2020 5:46 AM

We found carpet beetles in my closet shortly before we moved, about 1.5 years ago. I discarded the most heavily damaged sweaters, but there were others that I hoped to save. To avoid unleashing destruction in our new place, I examined those others closely, then put them in a sealed plastic container. Now, I just unsealed the container outside, re-inspected everything, and found one dead bug. Am I home free, or is it time to choose between treating these sweaters or discarding them?

Does the one bug I found (photos here) mean that carpet beetle eggs or live bugs I don't see could still be in the sweaters even after 1.5 years? Or with no other signs of bugs or their casings in that amount of time, can I safely release these sweaters into my closet?

If the former, then is there an effective but not totally inconvenient or expensive way to treat these sweaters? They can't take high-heat drying. There's a few of them that I might be willing to pay to dry clean if I have to, but not the others. I have diatomaceous earth, and I could get borax, but with either, I'm not sure if they work on eggs and all the life stages, and what exact lengths I'd have to go to in using them to be safe. E.g., shake the sweaters in a bag with ?? amount of the diatomaceous earth or borax, put them back in the sealed box for ?? amount of time, then shake the powder off and rinse the sweaters and let them dry?

posted by daisyace to Science & Nature (6 answers total)

Best answer: You can treat already-dry wool sweaters in the oven. I set it to the lowest temp (170 F for my oven), put the sweaters on a parchment-lined cookie sheet (1-2 per sheet) and leave them in for 30 min. Could probably also use a paper grocery bag.
posted by the_blizz at 6:07 AM on September 8, 2020 [3 favorites]

If it is still hot and sunny where you are and you own a car, you can put the sweaters in your car for a few days and let them "bake." This should kill any beetles (and moths as well). At the very least, it is an easy and free thing to try.
posted by mcduff at 7:17 AM on September 8, 2020 [2 favorites]

If it were me I would figure no more signs of damage means no ongoing infestation inside the bag. Maybe the dead one didn't have any fertile eggs to lay, or maybe the conditions in the bag killed it.
posted by Lady Li at 8:30 AM on September 8, 2020 [2 favorites]

Freezing them (possibly for a while, 2+ weeks, depending on the temperature of your freezer) would be an alternative to heat, I had success with this. Google will provide better advice on specific techniques than me at this point though, it's been a while.
posted by advil at 4:25 PM on September 8, 2020

Response by poster: Thanks! I’m not sure whether sweaters that can’t be dried on high heat can be baked without harm, but I could try with one or two to start.
posted by daisyace at 6:54 AM on September 9, 2020

I would check if they really can’t take any high heat at all, or whether they just can’t go into high heat when wet. A lot of sweaters will survive a trip through a dryer on hot, as long as they were already dry when you put them in.
posted by en forme de poire at 9:03 AM on September 12, 2020