[Exhibitman]

The article is very poorly researched and nothing new.

Mylar is the accepted standard storage material for paper artifacts at museums and the Library of Congress. It is considered inert and suitable for storage over hundreds of years. I don't think I will have my cards for more than 50 more years...so probably not a big deal.

Polypropylene is nearly inert. It isn't museum standard but it will last without changes for a very long time. The sheets are more likely to get scratched with handling than become unstable. I believe the card condoms in BVG holders are polypro.

I think I heard that the slabs at PSA and SGC are polystyrene, which is extremely resistant to acids as might be leached from cardboard.

I believe the threat to cards has been overstated. I have been collecting for 40 years. I have had cards stored in old vinyl pages and sleeves that have turned piss yellow and brittle as they have broken down. Not a single card has exhibited any staining indicative of any chemical migration.

For my good photos and paper items I use 4 mil Mylar pages from BCEmylar.com. They have two versions that come three-hole punched so you can easily store them in notebooks. For cheapo items I use Ultra Pro sheets, sometimes with an inner sleeve as well. For odd sized items, if they are smaller than 8 x 10 I usually use a smaller Mylar holder from BCE and put it into an Ultra Pro 8 x 10 sheet. That seems to be both secure and nice to look at. I like to flip through my albums regularly. I treat my postcards like photos.