Old woodworm treatment ..?????

[slick50]

I've been sanding back some old (early 50s) kitchen cupboards and found where they were treated for woodworm in a couple of places. I guess that's what it is because it's only in those areas. It's dark blue in colour and it obviously did the job, but now I'm wondering what it is .
Anyone seen a dark blue treatment before.

Thanks for any help ....

Kev ....

 

[Nige F]

Iodine

 

[slick50]

Nige, no idea. It has penetrated the surface of the wood but not too deep, so it took a bit more work to sand it out. I'm using a 3M mask with paint filters to be on the safe side. Too many people were too free using strychnine and arsenic based products in the early days

Kev ...