Why is this important?  If you are allergic to chemical dyes, if you are pregnant, recovering from from cancer, aor simply very concerned about your health, your physician has probably already recommended that you stop using chemical hair dyes and avoid all sources of toxins, chemicals and pesticides.

At present, there is no laboratory testing of and standard for what’s in a box labeled "henna".  “Pure, natural, organic, and top quality" are merchandising statements. They are NOT  scientific statements.  Only a laboratory assay will tell you what the lawsone content is in henna, the pesticide levels, and what additives or contaminants are in that henna.  Ancient Sunrise® laboratory certified hennas are independently examined by Alkemists Pharmaceuticals, so you'll know exactly what you're getting.  

 Henna is an agricultural product and it is not possible for the processed powder to be completely uniform: milling conditions, storage conditions, and shipping conditions will make a difference.  Even if it were possible for a factory to completely randomize henna leaves,  there would still be variations when the henna powder reaches the consumer.   A batch which has been tested may not be assumed to be the same as an untested product.