A dozen or so boxes of mounted 35mm colour slides has recently come into my possession - so, perhaps 300-400 individual slides.
These are my family's holiday and special occasion snaps, some on Kodachrome, some on a variety of "Boots", Ferrania/3M and other brands.
They date between the mid-1960s and perhaps late 1970s, and had (unfortunately) been stored for the past few years in a polyethylene bag in an outdoor concrete shed.

My intention was to scan them and distribute electronic versions to the remaining members of the family.

Opening one or two of the boxes, some seem to be fine, whilst others seem to have suffered deterioration.

An example is linked below. If I saw this on a lens, I'd assume it was fungus.

I am rather disinclined to put these through my scanner as I don't particularly want to distribute spores about the place (assuming this is fungus), and especially don't want spores transferred to any of my current B&W negatives which might also go through the same scanner.

Am I worrying unnecessarily?
Is there an easy way to cleanse/disinfect the damaged slides? (I mean by me - they are almost certainly not worth having professionally restored, even if that is the only way forward)

thanks for any advice