Hair dye is one of the most popular cosmetic products worldwide, but some of its ingredients continue to raise health concerns. Ammonia, a long-standing component of permanent dyes, is effective at fixing colour but may also come with risks. Recent studies and health experts have highlighted several ways in which ammonia affects the scalp, hair, and even the air we breathe in salons.
Irritation of the scalp and skin
Dermatology researchers have long noted the irritating effects of ammonia on the scalp. A 2022 review reported that ammonia-based dyes can trigger contact dermatitis, itching, and redness, especially in individuals with sensitive skin. For some, repeated exposure increases the likelihood of allergic reactions, which is why dermatologists strongly recommend patch testing before each use, even if the product has been applied before.
Respiratory discomfort in salons
Because ammonia is volatile, it produces strong fumes during the colouring process. According to a study published in Environmental Monitoring and Assessment, hair salon workers can be exposed to levels of ammonia in the air that cause irritation of the eyes, throat, and respiratory tract. The study stressed the importance of proper ventilation to reduce health risks for both professionals and clients, particularly in small or crowded spaces.
Effects on hair quality
Beyond skin and respiratory effects, ammonia can compromise the structure of the hair itself. Health specialists explain that ammonia aggressively opens the cuticle layer of the hair so colour can penetrate. While this makes dyes effective, it also leaves the hair more porous, which can lead to dryness, frizz, and breakage with repeated use. Many people who colour their hair frequently notice a loss of smoothness or increased brittleness, even when using conditioners included in dye kits.
Ammonia-free alternatives
In response to these concerns, cosmetic scientists have developed gentler formulas. One option is replacing ammonia with monoethanolamine (MEA). A comparative study published in the Indian Journal of Research in Dermatology (2021) found that participants using hair dye without ammonia experienced significantly fewer cases of irritation and scalp dryness than those using ammonia-based products, while still achieving satisfactory colour results. These innovations have fuelled the popularity of products like hair dye without ammonia, which are increasingly sought after by people with sensitive skin or already fragile hair.
Informed choices for consumers
Ammonia remains a common ingredient in many permanent dyes, but its drawbacks are now better understood thanks to dermatology and occupational health research. Irritation, respiratory discomfort, and hair dryness are real concerns, especially for frequent users or professionals exposed daily. The good news is that alternatives exist, and awareness is growing. Choosing gentler products, ensuring proper ventilation, and following safety recommendations such as patch testing can help consumers enjoy hair colour while protecting their health.
