Sterilizing cutting tools.

[DavidCampen]

In another thread we were discussing how to sterilize cutting tools to prevent the spread of virus. In that thread I said:

On further research I have to conclude that Physan is likely not capable of destroying most plant viruses.

I am going to have to rethink my tool (clippers) cleaning strategy. Hypochlorite is effective but it is corrosive to metal. Formaldehyde and glutaraldehyde are effective but they are nasty smelling and just generally nasty. Chlorine dioxide solutions are effective but are rapidly destroyed by sunlight. Alcohols are not very effective. I may have to start flaming my tools. I wonder if an alcohol lamp would be sufficient for flaming my clippers?


I have decided to move to flame sterilization, probably using a butane or propane torch.

One problem is the Fiskars brand shears that I am using have a lot of plastic - on the handle and in a lock slide.
I expect that I will likely eventually ruin that as I flame the blades. Japanese hand pruning shears are often available constructed only of metal. I would like some that have a spring that opens the blades. Does anyone have suggestion for a good but not too expensive brand?

[DavidCampen]

To answer my own question, I have decided to get Corona FS4350 and Corona FS4310 shears for evaluation.
Products : Corona Tools USA
They still have a plastic handle but it may be far enough from the blade to not be damaged and even if the plastic handle does melt it can be removed and not impare functionality.

For a torch I have decided to get an Iwatani chef's torch:
Amazon.com: Iwatani Torch Burner Professional #Cb-tc-pro: Kitchen & Dining

[glengary54]

Originally Posted by DavidCampen

To answer my own question, I have decided to get Corona FS4350 and Corona FS4310 shears for evaluation.
Products : Corona Tools USA
They still have a plastic handle but it may be far enough from the blade to not be damaged and even if the plastic handle does melt it can be removed and not impare functionality.

For a torch I have decided to get an Iwatani chef's torch:
Amazon.com: Iwatani Torch Burner Professional #Cb-tc-pro: Kitchen & Dining

David, Fiskar makes a very similar clipper for less than half the price.

[DavidCampen]

Originally Posted by glengary54

David, Fiskar makes a very similar clipper for less than half the price.

The prices on the Corona company website are full retail price, on Amazon you can buy them for less than 1/2 of that price.

The next problem that I want to address is that the tools still rust even though I am not using hypochlorite. I was looking for rust preventatives and it seems that lanolin is effective (and should not harm plants) so I plan to buy a commercial rust preventative formulated with lanolin as the active ingredient.

[Oscarman]

There are many wonderful things we offer on the OB and I am always happy to see that when search for orchid info it always leads to the OB.

So I am search for the effectiveness of Virkon to irradicate virus and other diseases and here I am again!

This thread has many excellent comments and advice - thank you all for your contributions.

What about the use of 70% USP Isopropyl alcohol for tool sterilization. Can anyone comment on the anti-viral effectiveness of tool storage or dip in this product? Can viruses survive? Does it take a short dip, or long term storage? Thx

[Leafmite]

The problem with using alcohol is that it is most effective with viruses that have an envelope (lipid covering) but most plant viruses don't seem to be this type. Alcohol does a great job with fungus and bacteria that affect plants (and even people) as long as there is enough exposure.

[Paul Mc]

I'll have to check these out! Thanks for posting the links!

[silken]

I have been told and read more than once that T.S.P. (the stuff to clean pain brushes etc.) is an excellent way to sterilize cutting tools. And supposedly it can be re-used as the effective part doesn't evaporate and I think the tools don't rust either. You mix it to a concentration that the water can't absorb any more of the granules. Can be found at most hardware and home improvement stores. I keep meaning to get some and this has just reminded me!

T.S.P. | Trisodium Phosphate Powder - 400 g | Home Depot Canada

[tucker85]

I've also been told that TSP works well for sterilizing tools. Chlorine works well also but it's rough on your clothing. When using a solution most people use two or more cutters so one can be sterilizing while using the other. I've been using a torch to sterilize my shears and I think it's the best solution for me. I haven't used the torch in the picture but it looks like a decent one. I don't know how long that little bottle will last though. It took me a few days to stop burning myself accidently by picking up the shears by the metal part. As far as the shears, I like any shears that are needle nosed. Shears with large blades don't work well around orchids.

[DavidCampen]

Here is a good study that was done at Ohio State as an undergraduate research project.
https://kb.osu.edu/dspace/bitstream/...NDA_THESIS.pdf

Findings were that hypochlorite (bleach) was by far the best but it causes corrosion of metal.

Two other oxidizing agents that worked well were ZeroTol and Virkon S. ZeroTol is the stabilized peracetic acid that Ray sells in RTU dilution. Virkon S is potassium peroxymonosulfate and is widely available in the U.S. Both ZeroTol and I think especially Virkon S will not cause the corrosion of metals like hypochlorite. All 3 of these - hypochlorite, ZeroTol and Virkon S have limited stability and probably need to be refreshed for each day of use. Also, with these and all other disinfectants, mechanical cleaning of the tool to remove dirt and sap prior to the disinfectant treatment is important.

After hypochlorite, the finding was that flaming was next best.

Surprisingly, a 20% solution of non-fat dried milk was found to be reasonably effective.

Quaternary ammonium compounds and TSP were found to be only slightly effective.

Virkon S:
http://www2.dupont.com/Emergency_Dis...ta%20Sheet.pdf

Virkon S Broad Spectrum Disinfectant | QC Supply