Are these metals are dangerous and not recomended for human strike branding?

the common metal to use is stainless steel but considering the dangers of other metals like toxicity in the blood, ect, can metals such as aluminum or tin or copper be used for household branding? or maybe a mixed alloy. and considering branding does burn through does that completely eliminate the risk of metals in the blood? Also does aluminum release aluminum oxide when heated? I do realize that the melting temperature of those three metals are in the middle to very low, and would not cause an effective brand. Thanks for any informatoin