I want to make a flask-style drinking vessel with no stain, finish, or anything. I am wondering if pine will be safe for this? I have heard of pine needle tea, but that's the needles, not the wood.
I found this chart on woods for smoking meat that says pine will make you sick, but that's if you burn it. I can't seem to find a definitive answer on drinking/eating off of unfinished pine.
I was once told by an instructor as a rule of thumb never to make something that will have food on it that does not bear food of some sort.
This was a very general statement, though we were making bread boards and cutting boards at the time and someone asked "what kind of wood" to use, to which he gave a small list, and then someone asked about "turning" a bowl for salad, and that was the instructors response. This was live and in person and no one famous or published, so I don't a reference for what he said and can't cite it either. However, I think that general statement holds true.
In general for that class, we were told to stay away from softer woods and porous woods as well. Softer woods will not take a beating with practical use and have a tendency to split over time due to the grains and how close the grains are. Additionally, with softer woods, with even smaller wear and tear, they will create pockets and microcosms that enable areas for bacteria to grow. The finish may be fine, but if it starts to split or tear in a certain area or even have a dent, then that could be a resting place for bacteria to start to grow. The same is true for porous woods. Porous woods on the other hand may be soft or hard, but will soak up the liquid more easily and possibly create an area where bacteria can grow.
A good short read on this for cutting boards would be this article.... https://www.cuttingboard.com/blog/why-some-woods-are-better-than-others-in-the-kitchen/
While that is a cutting board, the point the article makes I think make sense in terms of bowls and glasses and other food items. A couple points that article makes are about the difference of angiosperm and gymnosperm trees, as well as the mechanism in which the tree transports water, medullary rays vs pores.
An example of the above, I tried to make a cutting board out of Cucumber Wood once. I happened to get a large amount from someone for free and just finished that class and thought it would be nice. While it was good practice, turns out that cucumber wood is not toxic, though more porous and a softer wood to work with. So it showed cuts very easily and is not very good for durability nor would it be good for food stuff.
I would also look at the Wood Database ( http://www.wood-database.com/wood-articles/wood-allergies-and-toxicity/ ) for types of wood to use and what the toxicity is and the impact. I think a pine cup or something might be nice practice, and might look or appear nice depending on the art that goes into it. However, I would not make anything out of pine that I would expect to be used for food. I was thinking of making a cutting board out of pine and then making a design on it and possibly putting inlays, but the intent would be for decoration, not function.
Pine, in general is good cheap construction wood. Grows fast, easy to cut down, strong enough to bear a reasonable load, easy to regrow. However, Pine is also poisonous to many animals and is an issue for livestock.
Looking at the list of woods for "smoking", almost all of the woods that are listed as "good" are trees that bear a fruit. Hickory and Oak, I believe are the only two that don't bear a visible fruit, though Oak produces acorns and some flowers as a fruit, and hickory will produce nuts until much older, and we could split hairs on that and the general rule of thumb. Which its meant more to make you think "that if the tree produces a fruit that one could eat, the wood from that same tree should be safe enough to hold food".
