Citrus: Lemon, orange, melon, pomegranate, neroli, and apple oils can give an unwanted yellow cast to hair.
Sulfates: These harsh detergents have a stripping effect on hair, damaging hydration and color.
Oxidizing Agents: Hydrogen Peroxide, bromates, and persulfates can break down natural and chemically processed color.
Color-Distorting Preservatives: Methylisothiazolinone, Methylchloroisothiazolinone, Diazolidinyl Urea, and Polyaminopropyl biguanide have also been shown to distort hair color.
Nitrogen Compounds: These compounds darken when exposed to air and light, which can stain your hair. Here’s a list commonly found in conditioners and hairsprays: Stearalkonium Chloride, Dicetyldimonium Chloride, Steartrimonium Chloride, Aminoethylaminopropyldimethicone, Divinyl Trimethylsiloxyamodimethicone, Bis-Hydroxy/Methoxy Amodimethicone, Aminopropyl Triethoxysilane, polymers (PVM/MA Coploymer, Octylacrylamide/Acrylates/Butylaminoethyl Methacrylate Copolymer, Polyurethane -1, Polyurethane-14, PVP/Vinyl Caprolactam/DMAPA Acrylates Copolymer, VA/Vinyl Butylbenzoate/Crotonates Copolymer), and compounds containing Triethanolamine (TEA), monoethanolamine (MEA), or Ammonia.