Toxins from TLUD biochar?

A simple number ten can TLUD biochar stove is an easy way to make small amounts of biochar and boil water without a lot of smoke. However, I'm wondering if anything would off gas from the burning coatings on the cans that would end up in the biochar.

Hopefully, I will be building a larger version soon to make biochar for my spring experiments.

Here is a picture of my TLUD in action.

Unlikely anything would get from the tin coating into the charcoal as it is all being oxidised.

"bio-char" is just a current fad term for charcoal. All charcoal will have a bio origin so "bio-char" is something that might be used by salesmen.

Charcoal on its own, as I understand it, is just char. To become biochar it needs to be inoculated, usually I hear of it being inoculated with urine.

Yes, Matu is correct.

To become biochar it needs to be inoculated

Although the char can be inoculated with any nutrient rich material, Urine is often used as it is nitrogen rich and serves well against the carbon surface, and it is also a liquid. Any liquid nutrients could be used, and it is probably best practice to use a liquid as it gets into all the internal surfaces of the char. It is not necessary to use a liquid however, and some of the other alternatives include manure, compost, fish fertilizer, AACT (Actively Aerated Compost Tea), EM (Effective Micro-organisms), or some combination thereof.

To answer the original poster's question to the best that I can figure: It is possible that there is some toxins off-gassing into the air as one does the burn at the beginning/first uses of the can system. When at a survival school, we used these cans for cooking, however we did a couple pre-cooks, one dry and hot, and the second with water boiling in the can, to get rid of toxins. After that, we cooked meals for a month of hiking and bush skills camping straight out of these cans, and I never felt healthier. At any rate, I doubt the toxins would get into the char. The reason I think this is because when the fire gets to it's second stage of burning, the char itself will be off-gassing, and the vacuum that is created as the fire draws these flammable gasses will also draw out the toxins, and burn them too. The ash from this first fire might have some toxins; after that, probably not much if any as far as I can think.