Need help with practical application of microwave death rays

[paris]

i am not fond of bleaching to sterilise items since i have to do them in my bath tub and i am below ground, so any wood parts/sand that make it in the tub will clog the drain more so since gravity doesnt help them as much going down the drain. so i am thinking as long as items fit in the microwave it will be a useful alternative. anything with a cell wall should die in this aparatus, including cists. my idea is for ceramic piece is to soak them so water will be what the microwave works on, and more important for me is for wood-i am thinking soak the item first so water is in all of its mass and as long as the water heats boils out it will be doing its job....so does any one think this is a bad idea? does any one use this technique?-(if so please give time&tehnique details) and has anyone ever read anything anywhere about this??

(Message edited by paris on March 27, 2004)

 

[brian]

I thought of doing this once and I forget what the reason was, but people told me it might not be that effective.

I think it was that it would basically be cooking them, not irradiateing (spelling?) them in the sense of destroying DNA with X-rays. So as long as you cook it long enough I figure stuff would die.

Oh yeah, make sure there's no hidden metal too I guess.

(Message edited by Brian on March 27, 2004)

 

[paris]

i wonder though since it ruptures cell walls weather it would destroy my cork bark or perhaps make it non floating.(my old pieces in old stable set ups sink already but i just add more for platforms.) i always have the option to boil smaller stuff too-any ideas on how long to destroy all potential harmful invaders??

 

[brian]

Well in order to rupture cell walls it needs water in them. Maybe if you let the cork bark dry out totally somehow? I honestly don't know though.

 

[matthew]

Hi Paris,

I am aware of someone using this here in the uk. I didn't actually see the programme but a colleague at my workplace told me (knowing about my collection!) all about it... they had watched a popular tv programme about pets and a keeper of fire sals (terrestris, apparently)had demonstrated his cleaning routine. This entailed zapping his (wet?) cork bark in the microwave. I considered doing it but can't help feel that a kettle of boiling water kills enough bad bugs.
Just wanted to let you know at least one other person has had this idea and carried it through.

Best//M

 

[alan]

Microwaving complex organics will not generally be any more effective than immersion in boiling water. I hate bleach residues too, so I think you're wise to avoid these on porous objects. If you really want to sterilize stuff, you'll need an autoclave (don't bother, it's not necessary).

 

[edward]

Hi All,
Unless you are trying to reuse items from one cage to another then items like cork bark do not typically need to disinfected, although I do rinse these items off with a hose before using them in an enclosure (if they are really dirty then I scrub them with warm water and a soft brush until they are clean).
I would recommend not reusing porous items like cork bark between enclosures to decrease the transmission of parasites and other potentially pathnogenic organisms as unless they are autoclaved they cannot be effectively sterilized. (Cork is an insulating material and
all of the pores make it difficult to sterilize so sterilization by boiling is difficult as it would need to be totally submerged for at least 15 minutes).
When sterilizing any items all dirt/sand/grit or organic material needs to be washed off the item before sterilization can occur as the dirt/sand/ or organic materials will either shield items or absorb the disinfective agent preventing effective sterilization.
In general the minimal time frame that an item needs to be exposed to the disinfecting agent is 15 minutes at the proper dilution ratio. Some disinfectants are less effective at higher concentrations so the recommended dilution ratios should always be observed.
I suspect that microwaving an item like corkbark to be ineffective as there is little water in the bark and instead parts may ignite/burn (like popcorn left in a little too long) before the whole mass reaches sterilization temperatures.

As a side note one of the ways to eliminate the bleach residues is to soak the disinfected item in a solution made from a dechlorinator like Amquel. This is very effective and if the first soak was insufficient, more dechlorinator can be added and the container stirred until the smell of chlorine is no longer evident. At which point the item can be air dried and rechecked for the odor of chlorine. Any tubs of bleach disinfectant can also be neutralized in this manner decreasing any enviromental impact.

Ed

 

[jennifer]

Paris, I boil cork bark and other porous items when I reuse them. I hold cork bark submerged in the boiling water for about a minute.

For non-porous items, I just scrub them and let them dry thoroughly before reuse. I suspect Ed will tell me that this doesn't kill all the germs

 

[jessica]

I'm not an expert on this either but any items I buy to put into the tank I scrub first then boil, probably like 10 minutes and not 15 (although after reading Ed's post I should probably have more patience and wait the extra 5 min). I bought a scrub brush that I keep just for this purpose. What I can say is that when I scrub the items before boiling(for example slate rocks) A lot of dirt comes off. Good luck with whatever you decide

 

[edward]

Hi Jen,
In general I am not concerned with the bacteria as many of the bacteria that cause infections in amphhibians are going to be present in the enclosure regardless of the steps taken as they are a common part of the enviroment (such as Aeromonads and Pseudomonads). One of the exceptions to this would be mycobacterial spores. (but these are still common in the soil and other artifacts from the enviroment and if you have an outbreak of this you are much better off disposing of everything than trying to disinfect the cage furnishings.)

With amphibians, I am more concerned with the transmission of parasites as opposed to bacterial infections (although if you do have an outbreak I would not recommend reusing anything from that cage that cannot be easily disinfected).
For example one of the nematode types that can infect amphibians has two options for an adult stage, free living and parasitic. The adults of both stages produce free living and parasitic larva (the parasitic adults live in the lungs). If all of the free living adults/larva are not killed; infection/reinfection of the amphibians is inevitiable as the parasitic larva can burrow through the amphibian's skin (some species attempt to infect humans resulting in larva migrans).

Paris,
It may be better for you to get a plastic blanket box to wash/disinfect the various cage furnishings. This way you can wash them, allow the larger debris to settle and pour off the non-gritty portion and the rest may be able to be poured/siphoned through a brine shrimp net to keep the bottom of your tub clean.

Ed

 

[caleb]

An autoclave is just a big pressure cooker- I've sterilised soil (for growing delicate cacti from seed) in a domestic pressure cooker in the past.

An oven could be used to sterilise wood or rock if you're really paranoid- 150C should be enough to kill pretty much anything.

I wouldn't sterilize soil/compost in an oven, though, as drying out fully can affect its ability to hold water.

 

[edward]

Hi All,
Using an oven can be dangerous and expensive. If the rock contains water pockets, heating it past the boiling point (which is required to sterilize the item) can cause the rock to explode sending rock fragements all over the place possibly damaging your oven and/or causing injury if you are checking the item at the time of the explosion.
I do not recommend this method and if anyone chooses to sterilize stones/rocks this way to be very very careful.

This is also not as effective as using an autoclave as the increased pressure makes the process more effective (this will destroy most bacterial spores unlike simple boiling or baking).

Ed

 

[alan]

Same caveats re. explosion also apply to microwave ovens.
Ever tried boiling an unpierced egg in a microwave?
Don't.

 

[edward]

Hi Alan,
There is another risk in trying to microwave stones is that there are often metals or metal ores in the stones which can really wipe out your microwave.

Ed