Does freezing kill nymphs? Eggs?(4 posts)
I read a piece about BBs linked from a PCO website, courtesy of the state of North Dakota. It said that "only adults are found at temps below 50F".
So, I've read all about how my kitchen freezer will not kill BBs.
Is the ND piece correct? How long does it take for non-adults to die at < 50F?
Does freezing (0-20F) kill eggs?
If I have a non-washable item (say shoes, belts, bag) would a dusting of DE (I was thinking to shake it in a bag) take out the adults & nymphs and freezing take care of the nymphs and eggs?
Link to the ND document are at this PCO (no endorsement) http://www.garriepestcontrol.com/Common_Pests/Bedbugs.pdf Looks like the state of ND no longer has this doc.
Not sure but I think the text you cite is referring to the effect of temperature on the life-cycle of the bed bug, vis-a-vis "ideal" living conditions. Apparently, one researcher found that eggs don't hatch below 44.5dF and bedbugs can't complete their development cycle at temperatures below 55.4dF (Johnson, 1941).
About freezing... the Australian CoP references (as yet unpublished) research that suggests freezing might be a good choice and it will kill all life stages (p. 29):
Any item for freezing should be placed loosely into a bag, and as always, this must be done in the infested room prior to removal. The amount of time in the freezer would be dependent on the size of the item; the larger the item, the longer in the freezer. If the freezer is operating at or around -20oC, then two hours at this temperature will kill all stages. However, for the average household freezer, studies indicate that 10 hours will be required (Naylor & Boase, pers. comm.). Dense items may take several days for the centre to cool sufficiently to kill the bugs and the longer an item is kept frozen, the more likely the bugs will be destroyed. Naylor and Boase suggest that 10 hours of freezing is required per 2.5kg of dry weight of laundry.
The question is how cold is your freezer? These researchers seem to think a household freezer does get to -17 or -20dC (-17dC is the minimum required).
The important caveat here is Lou Sorkin placing bedbugs in a freezer at -29dF (which would be -33.8dC) and finding them (some of them) still alive after 4 hours, but finally all dead at 5 days.
I'd freeze for a couple of weeks rather than 10 hours.
Dust in a bag is probably hit or miss, and dust in shoes (which might come in contact with your skin) isn't a good idea.
Some people put items with DDVP (dichlorovos strips) in a sealed bag. I am not recommending this method, but I have tagged this thread "ddvp" so you can click the tag and see the threads on that. Do your research-- it's a controversial method, but might be useful in such a situation.I started and run the site but am "not an expert."
I just popped one of my "test subjects" into my home freezer and it was dead in under 24 hours. (I've let it thaw and it's truly dead, not dormant or something like that.) That was an adult. I'm guessing the eggs are more resilient and the nymphs are less so. Of course, it was also just in a baggie, if it was in the middle of something like a shoe or a book it would take longer to freeze it, since the surrounding material would have to get cold.
I don't have a temp for my freezer but I do know it's not even set at the coldest setting.
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