AMMONIA
Ammonia can have damaging effects to your health, both internal and external these include:
Inhalation of ammonia of lower concentrations in the air can cause coughing, irritation of nose and throat, rapid skin and eye irritation.
Ammonia also has a negitive effect on the hair. It penetrates into the cuticle of the hair and damages the amino acid protein called Tyrosine. Tyrosine is important because it produces a natural pigment found in the hair shaft, called Malenin. When this is damaged the hair's ability to hold onto color is greatly reduced or eliminated. If a hairdresser introduces color into the hair shaft without damaging the Tyrosine, the color can last longer because it has something to bond to.
BRIGHT, FRESH, NEW FADDED, NO COLOUR HOLD
Source:
http://www.organiccolorsystems.com/why-you-dont-want-ammonia-hair-color
