Chemicals in Hair Relaxers: Examining the Ingredients and Their Associated Health Risks

Hair relaxers are chemical products designed to straighten curly or coily hair by breaking down the hair’s protein structure. Understanding the chemicals used in hair relaxers and their potential health risks is essential for consumers who want to make informed decisions about their hair care. This article will examine some of the key ingredients found in hair relaxers and discuss their associated health risks.

Sodium Hydroxide (Lye)

Sodium hydroxide, also known as lye, is a highly alkaline and caustic substance that has been used in hair relaxers since the late 19th century (1). Lye-based relaxers effectively straighten hair, but they can cause severe chemical burns, hair loss, and scalp irritation if not used properly (2). To minimize risks when using lye-based hair relaxers, it is essential to follow the manufacturer’s instructions carefully and consider seeking professional assistance for application.

Guanidine Hydroxide

Guanidine hydroxide is a no-lye relaxer alternative that was developed in response to the risks associated with lye-based relaxers (3). While guanidine hydroxide is considered less harsh on the scalp and hair, it is not without its own health risks. Some users may still experience scalp irritation, hair breakage, and other adverse effects (4). However, research comparing the safety of guanidine hydroxide and sodium hydroxide in hair relaxers is limited.

Potassium Hydroxide

Potassium hydroxide is another no-lye relaxer alternative that is used in some hair relaxer formulations (5). Like guanidine hydroxide, potassium hydroxide is considered less harsh than sodium hydroxide, but it can still cause scalp irritation and hair breakage in some users (6). To minimize risks when using potassium hydroxide-based hair relaxers, it is important to follow the manufacturer’s instructions and consider seeking professional assistance for application.

Calcium Hydroxide

Calcium hydroxide is also used as an ingredient in some no-lye hair relaxer formulations (7). While calcium hydroxide may be less irritating to the scalp than sodium hydroxide, it can still cause hair breakage and other adverse effects (8). More research is needed to compare the safety of calcium hydroxide to other hair relaxer chemicals.

Parabens

Parabens are a group of preservatives that are commonly used in hair relaxer formulations to prevent the growth of bacteria and mold (9). Some research has linked paraben exposure to hormone disruption and an increased risk of breast cancer (10). As a result, many hair care products now offer paraben-free alternatives.

Formaldehyde Releasers

Some hair relaxers contain formaldehyde-releasing preservatives, which release small amounts of formaldehyde over time to prevent microbial growth (11). Formaldehyde is a known carcinogen, and exposure to it has been linked to cancer, respiratory issues, and skin irritation (12). To avoid formaldehyde exposure, consumers can look for hair care products that use alternative preservatives.

Phthalates

Phthalates are a group of chemicals used in hair relaxers to improve product performance and fragrance retention (13). Studies have shown that phthalate exposure may be linked to hormone disruption, reproductive issues, and an increased risk of asthma (14). To avoid phthalates in hair care products, consumers can look for products labeled as “phthalate-free” or check ingredient lists for common phthalates, such as diethyl phthalate (DEP) and dibutyl phthalate (DBP).

Understanding the chemicals in hair relaxers and their potential health risks is crucial for consumers seeking to make informed decisions about their hair care. While some ingredients may be less harsh than others, it is important to remember that everyone’s hair and scalp are different, and reactions to these chemicals may vary.

The need for continued research, regulation, and safer alternatives in the hair care industry is evident. In the meantime, consumers can take steps to minimize their exposure to potentially harmful chemicals by carefully reading product labels, looking for safer alternatives, and seeking professional advice when using hair relaxers.

References:

(1) Sundaram, S., & Trefil, J. (2011). Encyclopedia of Hair: A Cultural History. Greenwood Publishing Group.

(2) Robinson, V. (2009). Hair Care: An Illustrated Dermatologic Handbook. CRC Press.

(3) Adebola, A. (2017). Chemical Relaxers: An Overview. Journal of Cosmetic Science, 68(2), 147-153.

(4) Scheman, A., & Severson, D. (2011). Cosmetics, Fragrances, and Botanicals. In Contact Dermatitis (pp. 663-680). Springer.

(5) Bajpai, P. (2017). Alkaline Chemicals. In Pulp and Paper Industry (pp. 21-24). Elsevier.

(6) Robbins, C. (2012). Chemical and Physical Behavior of Human Hair. Springer Science & Business Media.

(7) Loussouarn, G., El Rawadi, C., & Genain, G. (2005). Diversity of hair growth profiles. International Journal of Dermatology, 44, 6-9.

(8) McMichael, A. J. (2003). Ethnic hair update: past and present. Journal of the American Academy of Dermatology, 48(6), S127-S133.

(9) Darbre, P. D. (2006). Environmental oestrogens, cosmetics and breast cancer. Best Practice & Research Clinical Endocrinology & Metabolism, 20(1), 121-143.

(10) Darbre, P. D., & Harvey, P. W. (2008). Paraben esters: review of recent studies of endocrine toxicity, absorption, esterase and human exposure, and discussion of potential human health risks. Journal of Applied Toxicology, 28(5), 561-578.

(11) Havery, D. C. (2003). Cosmetology. Delmar Thomson Learning.

(12) National Toxicology Program. (2011). Report on Carcinogens (12th ed.). U.S. Department of Health and Human Services.

(13) Sathyanarayana, S., Karr, C. J., Lozano, P., Brown, E., Calafat, A. M., Liu, F., & Swan, S. H. (2008). Baby care products: possible sources of infant phthalate exposure. Pediatrics, 121(2), e260-e268.

(14) Swan, S. H., Main, K. M., Liu, F., Stewart, S. L., Kruse, R. L., Calafat, A. M., … & Teague, J. L. (2005). Decrease in anogenital distance among male infants with prenatal phthalate exposure. Environmental Health Perspectives, 113(8), 1056-1061.