If you dye, bleach, or perm your head hair, you can submit a tablespoon of pubic hair as an alternative. You simply cut the pubic hair as close to the skin as possible.
If you do submit head hair that has been treated, it can serve as a good indicator whether your hair treatment and product brands are highly toxic, or not. If the toxins common to many hair treatments show high on your hair report, then you will know that you should change product brands, or stop treating your hair with these chemicals.
If the toxic elements typically used in common hair treatments are NOT elevated on your hair report, then you can have the confidence that the brands you are using are a good quality, and are more pure and natural.