Nylon fabric, a synthetic polymer (polyamide), is widely used in clothing and gear for its strength and durability. While the fully cured polymer is generally considered non-toxic and inert, safety concerns arise from residual chemicals left over from manufacturing and various surface treatments. These residues and finishes can pose potential health risks, primarily through skin contact and absorption. This article explores the specific chemical compounds associated with nylon fabric.
The Core Chemistry: Is the Polymer Itself a Risk
Pure nylon, once fully polymerized, is an unreactive material that does not typically release volatile organic compounds. Nylon 6 and Nylon 6,6 are created from petrochemical-derived components. Since the manufacturing process rarely achieves 100% conversion, small amounts of uncured raw materials can remain in the finished fiber.
The primary chemical concern is residual monomer, such as caprolactam in Nylon 6. Although regulatory agencies consider the levels in finished textiles low, this residue can still off-gas or leach out. Other residual chemicals, including antistatic agents like barium sulphate or trace amounts of formaldehyde, may also be retained by the nylon fabric.
The Hidden Hazards: Dyes and Chemical Finishes
The greatest source of potential toxicity in nylon apparel is the vast array of chemical additives applied after the fiber is spun. These functional chemicals enhance color, durability, and performance, but they can be loosely bound and may leach out during wear.
Vibrant and dark colors often use azo dyes, some varieties of which can release carcinogenic aromatic amines when exposed to sweat. Disperse dyes, common on synthetic fibers, are also recognized skin sensitizers that can trigger allergic reactions.
Water and stain-repellent finishes frequently utilize Per- and polyfluoroalkyl substances (PFAS). These “forever chemicals” are known endocrine disruptors linked to hormone disruption and immune system suppression.
Other treatments include flame retardants, formaldehyde-based resins for wrinkle resistance, and phthalates. Phthalates are used as plasticizers to increase flexibility. Formaldehyde is an irritant and potential carcinogen, while phthalates are associated with endocrine disruption.
Direct Health Impacts: Skin Irritation and Absorption
The chemicals embedded in or applied to nylon fabric can cause direct physiological reactions in the wearer. The most common is textile contact dermatitis, which can be either non-allergic irritation or an allergic reaction to dyes or finishing agents. Symptoms include redness, itching, and scaling, often appearing where the fabric is tight or friction is high (e.g., waistline, armpits).
Chemical absorption is facilitated by the fabric’s interaction with the skin, especially during physical activity. When a person sweats, moisture and oils act as a solvent, dissolving lipophilic chemicals like PFAS and phthalates out of the fibers. This makes the substances available for absorption through the skin. Nylon’s low breathability traps heat and moisture, which can exacerbate existing skin conditions and encourage bacterial or fungal infections.
Mitigating Exposure and Safer Use
Consumers can take practical steps to reduce exposure to potentially harmful nylon fabric chemicals. The simplest action is to always wash new nylon clothing before the first wear, which helps remove surface chemical residues and excess dyes. Choosing undyed or lighter-colored nylon items can also minimize exposure to concentrated dyes.
Consumers should be skeptical of marketing terms like “stain-resistant,” “anti-odor,” or “wrinkle-free,” as these typically indicate the presence of chemical finishes like PFAS or formaldehyde. Those concerned about chemical content should look for third-party certifications, such as the Oeko-Tex Standard 100 or Bluesign. These certifications verify that the finished textile has been tested for and is free from harmful levels of regulated substances. When wearing nylon for prolonged periods, selecting fabrics with enhanced moisture-wicking properties and ensuring adequate ventilation can help prevent chemical leaching and skin irritation.