Well, there are going to be food shortages.

[chowmama]

21. pH 4.6 is the cutoff, according to my sources

4.5 or lower, you're ok with a boiling water bath.

Farm Journal canning book is the source, but it seems reasonable. After all, pickles need to be made with 5% vinegar which has a pH of 2.4 to 2.7 After that, allowing for dilution from the ingredients, it might go up a couple of points, but probably not more. A whole lot of the pickling process like salting and draining is meant to keep there from being too much dilution.