Soap is alkaline.

According to this source mild dish soap is ph neutral or close to it. And according to Mrs Meyers, their rosemary dish soap is ph neutral.

Caldrea also says their dish soap is ph neutral.

I have some issues with skin sensitivities to personal care products. I bought a cheap pH tester on Amazon.

It has been fascinating. My tapwater is straight neutral. All hair and skin products I have tested are somewhat acidic, as they are supposed to be. At least for most adults. We are born neutral and return towards it as we age, but as teens and adults our exteriors are acidic.

Don't wash your hair in the kitchen!

Ask your fabricator to either make you a cutting board or give you a reasonable sized piece of remnant that is sealed. I tested dishsoaps by living a drop of full strength soap on my cutting board for a few hours. Seventh Generation Natural Dish Soap Free & Clear & Williams Sonoma Lemongrass Ginger both passed. I only tested a few & didn't test Mrs Meyers.

You can also buy litmus paper at the drug store - cheap and easy way to test pH. I would look for locally made "green" brands of dish soap that are easy for you to get and just test them. Good idea to look into that.

Thanks. Litmus strips at the drugstore sounds like a wnner. I also have a sample of honed carrara so I can test on it too. (I should make this my kid's science fair project and make him do all the testing, shouldn't I?)

Love the science fair idea! The Geiger counter idea was another good one. Let's put those kids to work for a change! :)