Greetings, this is my first ever post here so apologies for any stuff ups! So I recently got a three second hand pipes, and I noticed that two of the pipes had stems made of aluminium. I've read about the dangers of smoking with aluminium so I was wondering if it is safe as only the stem is made of aluminium not the bowl? The other pipe has a stainless steel stem of some sort I'm pretty sure. All of the pipes have bowls of brass (immaturity test ) Are these pipes safe? I'm asking here because I couldn't find any info with google about aluminium stems, all the search results were about not using aluminium to make bowls and stuff with. Thanks for any input. Peace!