The potential cancer risk posed by everyday clothing is a growing public concern, driven by awareness of the complex chemical processes used in textile manufacturing. Clothing is treated with hundreds of substances to achieve desirable qualities like wrinkle resistance, specific colors, or water repellency. This article examines the potential link between residual chemical components in textiles and long-term health effects, focusing on the actual risk consumers face.
The Scientific Verdict on Clothing Carcinogens
Major health organizations agree that the overall cancer risk associated with typical consumer clothing in developed nations is very low. Bodies like the World Health Organization (WHO) and the Environmental Protection Agency (EPA) do not list finished textile products as established cancer risk factors. This is due to regulatory limits on chemical residues and the low quantity of chemicals that actually transfer to the wearer.
It is important to distinguish between hazard and risk in this context. While many substances used in textile production are classified as potential human carcinogens, this classification often relies on high-level, long-term occupational exposure studies. The consumer’s exposure level is significantly lower than that of a factory worker handling raw chemicals. Therefore, a chemical’s inherent hazard does not translate into a substantial risk for the average person wearing the finished garment.
Public health bodies focus cancer prevention guidance on established factors like tobacco use, UV radiation, and diet. Clothing is often cited in a protective role, such as wearing tightly woven fabric to reduce sun exposure. However, this general reassurance does not dismiss the need to understand specific chemical compounds that remain in textiles and their potential for chronic, low-level exposure.
Specific Chemical Compounds in Textiles
A number of chemical classes are used in textiles that include compounds known or suspected to be carcinogenic under high exposure conditions.
Formaldehyde
Formaldehyde is a common chemical used in finishing processes to give fabrics properties like wrinkle resistance, anti-mold protection, and color fixation. The International Agency for Research on Cancer (IARC) classifies formaldehyde as a known human carcinogen, with evidence linking it to cancers of the nasopharynx and leukemia. This classification is primarily based on inhalation exposure in occupational settings.
Azo Dyes
Azo dyes provide the vibrant colors seen in approximately 60% to 70% of industrial dyes. Certain azo dyes can break down under specific conditions, such as prolonged storage or contact with sweat, into carcinogenic aromatic amines. These amines, including compounds like benzidine and \(o\)-toluidine, are recognized for their potential to induce cancer, and their use is restricted by regulatory bodies in many regions.
Heavy Metals
Heavy metals are incorporated into textiles, typically to fixate dyes onto fibers or to create specific pigments. Chromium, cobalt, and lead are examples of metals used for this purpose, particularly in wool, nylon, and silk. Hexavalent chromium compounds are known human carcinogens, while cobalt is classified as a possible carcinogen. These substances, even in trace amounts, can accumulate in the body over time.
Flame Retardants
Flame retardants, often containing brominated or organophosphate compounds, are added to certain textiles like children’s sleepwear or furniture fabrics to meet flammability standards. Some of these compounds, such as tetrabromobisphenol A (TBBPA), have been linked to endocrine disruption and are suspected carcinogens. The long-term health effects of many currently used substances are still being investigated.
Mechanisms of Exposure and Absorption
Chemical residues in clothing primarily interact with the body through two pathways: direct dermal absorption and inhalation of volatile compounds. Dermal absorption occurs when a chemical transfers from the fabric to the skin and then penetrates the skin barrier into the bloodstream. This process is significantly influenced by conditions that compromise the skin barrier or increase chemical solubility.
Factors like heat, sweat, and friction increase the rate of chemical absorption from clothing. Sweat acts as a solvent, dissolving non-bonded dye particles and chemical finishes, while friction from movement physically facilitates the transfer to the skin’s surface. The chemical’s lipophilicity, or ability to dissolve in fats, also plays a role, as the skin’s outermost layer is rich in lipids.
Inhalation exposure typically occurs via off-gassing, where volatile organic compounds (VOCs) evaporate from the fabric into the air. Formaldehyde is a common VOC released from new or chemically treated textiles, often contributing to the distinct “new clothing smell.” Breathing in these compounds, especially in poorly ventilated spaces, is a route of exposure that can lead to systemic effects. Furthermore, microscopic fabric particles containing chemical residues can break off and be inhaled or ingested, particularly by small children.
Reducing Personal Risk Through Safer Clothing Practices
One of the most effective and actionable steps consumers can take to reduce chemical exposure is to always wash new clothing before wearing it. This simple practice removes a significant portion of the unbound chemical residues, including surface-level dyes and residual formaldehyde. Washing new clothes helps to mitigate the initial, often highest, level of exposure.
Consumers can minimize risk by making informed choices about the types of fabrics they purchase. Opting for natural fibers like organic cotton, linen, or hemp can reduce the likelihood of encountering the high concentrations of chemical finishes associated with synthetic or performance fabrics. The growing popularity of second-hand clothing also provides a benefit, as garments that have been washed numerous times have had most of their residual chemicals removed.
Understanding third-party certifications helps consumers select products that have been tested for harmful substances. Certifications like the OEKO-TEX Standard 100 ensure that every component of a textile, including threads and accessories, has been tested for hundreds of regulated and unregulated chemicals. Similarly, the Global Organic Textile Standard (GOTS) verifies that textiles are made from organic raw materials and restricts the use of toxic inputs throughout the manufacturing process.
Finally, consumers should be mindful of clothing marketed with specific functional treatments, as these often indicate the presence of chemical finishes. Features like “wrinkle-free,” “stain-resistant,” or “anti-odor” typically rely on treatments containing persistent chemicals, such as formaldehyde or per- and polyfluoroalkyl substances (PFAS). Choosing untreated fabrics, particularly for items worn close to the skin for long periods, like underwear and sleepwear, is a practical way to lower daily chemical contact.