@OP, I think you may have misunderstood the information that was generated.

The gel nail polish formulas you posted are very industry standard. I personally handle all these sorts of materials every day in their pure form (albeit wearing gloves and a lab coat).

Are they perfectly studied and definitely have no ill effects? No.

Are they generally considered pretty safe by most people who use and regulate them? Yes.

Thank you so much for your reply and taking the time to download the pdf and look through it.

I figured they weren’t putting anything outrageous inside them. But for some reason a lot of people have started a lot of fear mongering with the gel nail product brands that are based in China, while doting and raving about products from companies that aren’t inside China but do all the manufacturing there …

So I just wanted to double check and very much appreciate it !

Procedure as worded is ambiguous - acetate buffer means a buffer made by mixing acetic acid with some acetate (typically sodium), but what are concentrations of these and what is their ratio is in no way obvious. Acetate buffer typically means something between pH 4 and 5.5, exact value can be important, or it can be not, depends on the reaction details.

Buffer has to be selected carefully, so that it doesn't interfere with the detection reaction. Say, if you detect chlorides with Ag⁺, any ion reacting with Ag⁺ will give you a false positive. Acetate buffer is a common selection in such cases.

The procedure doesn't say anything about concentration. It just says "moisten a strip of potassium iodide starch paper with the sodium acetate buffer." A little more detail about the procedure, it is a two part check for cyanide in waste water. The first check is for chlorine and the second is for sulfide. Both checks require the sodium acetate buffer.

A sodium acetate buffer contains the equal moles of sodium acetate and acetic acid. The concentration  and the to achieve pH you have to know.  Calculation with Hendersson Hasselbalch equation.