I can highly recommend a pubic hair analysis for heavy metals. Pubic hair is not generally colored, it grows slower and is a better substance to verify the presence of heavy metals. It concentrates toxins more so than head hair. I have done hair testing for 15 years and use many labs, but always request pubic hair if there is the slightest possibility of colored, permed, dyed or bleached hair. Bear in mind that HPLC mass spectrometry can determine even the tiniest amount of heavy metal, which means the tiniest speck of hair contaminate will show up quite strongly. Food for thought.