Tea Tree Shampoo

Why it's rated this way

2 ingredients on this label are flagged. A cosmetic's rating is set by its most serious finding — here, Methylisothiazolinone.

1. MethylisothiazolinoneHigh concernPotent contact sensitizer; banned in EU leave-on cosmetics since 2017.

   What it is

   Its recorded role: preservative and antioxidant. About Methylisothiazolinone

   Why it's flagged

   Potent contact sensitizer; banned in EU leave-on cosmetics since 2017.

   Regulatory basis

   EU Cosmetics Regulation, Annex V — permitted preservative, with a concentration limit; Greenveil's curated cosmetic-ingredient concern list.

   How sure we are

   High confidence. The label names this substance exactly.

2. Sodium hydroxideMinor concernAlkali (lye). It is used up in the product: as a pH adjuster it neutralises an acid in the formula, and in soap it turns the oils into soap. The EU caps the alkalinity it may leave (pH 11 for pH-adjuster use); the higher limits, with warnings, are only for hair straighteners, cuticle removers and depilatories.

   What it is

   Its recorded role: buffering and denaturant. About Sodium hydroxide

   Why it's flagged

   Alkali (lye). It is used up in the product: as a pH adjuster it neutralises an acid in the formula, and in soap it turns the oils into soap. The EU caps the alkalinity it may leave (pH 11 for pH-adjuster use); the higher limits, with warnings, are only for hair straighteners, cuticle removers and depilatories.

   Regulatory basis

   EU Cosmetics Regulation, Annex III — allowed only within set limits and conditions; Greenveil's curated cosmetic-ingredient concern list.

   How sure we are

   High confidence. The label names this substance exactly.

Assessed against the label as captured: 13 of 21 ingredients recognised.