Woodworker and person who has spent a tremendous amount of time on wood finishing chemistry here.

This is very confused.

First, all wood finishes you can buy are food-safe once cured. They aren't allowed to be sold otherwise, at least in the US/Europe/et al.

If you are using them once heated, this is not always as true (and regulations vary a bit), but if we are talking about food prep/salad/you name it, they are all safe.

Heat wise, if we are talking about using it in boiling water to stir something, most finishes would be fine from a safety standpoint (not all can withstand this though).

As a general rule of thumb, if you aren't heating the wood above 200F, you aren't really going to get a finishes to release toxic fumes[1]

Second, as for solvents - smell is not everything. The HDI he mentions rubio having will not smell like anything until the concentration is way way way way too high. If you can smell it, you are in trouble. HDI is also much more dangerous than most solvents[2].

The oil is also a solvent.

Solvents are just things that you can dissolve something else in.

If they want to avoid certain types of solvents for some reason, that should be about safety or something, and if they want to evaluate that, smell is probably the wrong evaluation criteria.

To give one example of solvent elimination with a purpose, let's take VOC's, which are about pollution[3].

Avoiding VOC solvents makes for cleaner air, but again, VOC compliant/exempt/etc solvents vary wildly in whether they are safer for people or not than non-VOC exempt solvents.

If you are trying instead to avoid human-toxic solvents, you would choose a different set, etc.

[1] There are so many finishes with so many different properties that i can't 100% guarantee this, but non-professional stuff you can buy at a woodworking store or a big box store is going to be fine

[2] The lack of smell of isocyanate's is main the reason you can get service life indicating respirator catridges from 3m/et al - otherwise you would not be able to determine if your cartridge is working or not, since you would not smell it when spray finishing/etc until the concentration is way too high, even if your cartridge is spent. Sane folks just use supplied air anyway, rather than risk it at all.

[3] not safety to humans, though often highly confused with being safer.

I expect most would count baking and candy making among "food prep." the latter of which routinely reaches temperatures around 200-300°F. If stirring a mixture of boiling sugar for 20 minutes at 230°F exceeds the expected food-safety threshold, it seems like there shouldn't be as casual a usage of terms as this:

> If you are using them once heated, this is not always as true (and regulations vary a bit), but if we are talking about food prep/salad/you name it, they are all safe.

I've been using Osmo oils. This top oil and also their butcher block. Besides what they say that it is food safe, would this be fine for utensils which may get exposure to cooking temperatures ? Whether mixing soup or stir fry ?

https://osmo.ca/product/topoil-high-solid/

Honestly I just use the utensils unfinished. They work fine and survive dishwashing fine. I still have over 20 years old cooking spoons that go through this kind of abuse.

First, all wood finishes you can buy are food-safe once cured.

Standard BLO is not food-safe and is sold everywhere.

Author here, to address some of your points:

- most finishes are indeed "food safe after curing", I'm aware of that. How they look on wood, how they perform when being dipped in hot soup or when drinking hot liquids from them, that's harder to assess without buying cans of finish that I have to store forever if I don't like them.

- HDI doesn't smell indeed, I never said it did. In fact two-component hardwax oils would have been perfect if it was easier to mix and apply in small quantities. Unfortunately for the few drops of oil I need on a spoon, it's too messy

- I'm talking about solvents in the definition that most consumers know about them: volatile solvents that usually smell strongly. I used low-VOC solvent-based finishes and they still smell. Organic components aren't the only smelly things in solvents, and I simply can't stand them anymore, that's all. It's not all about the dangers, it's for my own comfort.

If you can point me to a solvent-based hardwax oil that smells of only the oils and waxes inside, I'll buy it in a pinch and forget about melting waxes in my microwave. Google search doesn't help here, I need to hear it from someone with experience

"Sane folks just use supplied air anyway, rather than risk it at all."

For small one-time projects it's generally fine to just use a brand new filter and toss it afterwards. Hobbyists painting a car panel aren't using supplied air.

What if you're using it as a serving spoon from a boiling dish? How much heat can it withstand (or for how long) before it's unsafe