Materials safety, Brass, plumbers tape ?

[dStill]

Another quandary, i couldn't find a copper needle valve, so used a brass one, is this safe?
Will i get Lead poisoning?

Also, i could not find a compression fitting to fit my thermometer so I soldered a copper tube with about the inside diameter of the thermometer stem to the top cap, and used plumbers tape to complete the seal.
Will the Plumbers Tape contaminate the finished product?

Thanks anyone who could shed some light on this

[olddog]

You can de-lead the brass fittings with peroxide mixed with vinegar, just soak the complete fitting for half an hour then wash with water. Plumbers tape is PTFE which should not be a problem, I usually wind some around my thermometer to give a good fit, I also put 3-4 turns around the flange on my keg to form a seal with the column.

OD

[CletusDwight]

Wikipedia
"To enhance the machinability of brass, lead is often added in concentrations of around 2%. This lead is present on the surface of the material,"

I'm not convinced that brass really presents a hazard in the vapour path, provided that vapour doesn't condense on it and then drip directly into the collection vessel. Lead's pretty heavy and I would have thought that any lead containing organic compounds that might form would have a fairly high boiling point.

'Sides, when i was a youngster we had lead pipes for the water supply and lead paint on all the furniture and it ain't never done me no harm...

Did I just say that?

[HookLine]

Personally, I don't like brass valves, prefer stainless. Brass valves need to be de-leaded, are not as accurate (for needle valves at least), and the seals in them are inferior materials to those used in stainless.

Stainless cost a chunk more up front, but when you factor in the health benefits and longer life span of stainless (should last your lifetime), that extra cost is trivial.

[kubota]

An easier way to seal your thermo, is to drill a hole in a wine cork so it fits tight on the probe and then push the whole lot onto your copper tube.