Polyester, a synthetic textile derived from petroleum-based plastics, is one of the most widely used fibers in the global apparel industry. Its low cost, durability, and wrinkle resistance have made it a ubiquitous material in everything from fast-fashion garments to high-performance athletic wear. Despite its popularity, concerns are growing about the health implications of wearing this synthetic polymer close to the skin. This inquiry is driven by the potential for physical discomfort, exposure to residual manufacturing chemicals, and the shedding of microscopic plastic particles. Analyzing the scientific evidence can help clarify the potential risks associated with prolonged contact with polyester clothing.
How Polyester Affects Skin and Temperature Regulation
The physical structure of polyester fibers dictates how the fabric interacts with the body, particularly during periods of heat and physical activity. Polyester is fundamentally hydrophobic, meaning the fibers repel water rather than absorbing it like natural materials such as cotton or wool. This property is often marketed as a benefit in performance wear because it enables the fabric to wick sweat away from the skin for quick evaporation.
However, in tightly woven polyester fabrics, this water-repelling nature can trap heat and moisture against the skin, contributing to increased body temperature and discomfort. Studies examining subjects wearing polyester during exercise have found that it can lead to higher skin temperatures and greater sweat rates compared to natural alternatives. This insulating effect is counterproductive in warm or humid conditions, creating a microclimate that compromises the skin’s natural cooling process.
The retained warmth and moisture create an environment conducive to the proliferation of bacteria that naturally reside on the skin. Research has shown that polyester tends to adhere more bacteria and absorb more sebum, which serves as a nutrient source for these microorganisms. The metabolic breakdown of sweat components by these bacteria results in the intense odor often associated with synthetic fabrics. This environment can also contribute to skin irritation, rashes, or contact dermatitis for individuals with sensitive skin.
Chemical Exposure from Dyes and Manufacturing
Polyester clothing carries potential for chemical exposure from the various substances used in its creation and finishing, not just the plastic fiber itself. The manufacturing process for polyethylene terephthalate (PET) polyester involves catalysts such as antimony trioxide, a heavy metal compound that can remain as a residual component in the finished textile. Antimony exposure, which can be released during washing or thermal stress, has been linked in some studies to cardiovascular and pulmonary toxicity.
Beyond the raw material, polyester garments require chemical treatment to achieve desirable consumer qualities. Many textiles are treated with formaldehyde for wrinkle resistance, a substance classified as a human carcinogen that can leach out and cause allergic contact dermatitis upon dermal absorption. Specialized finishes often introduce endocrine-disrupting chemicals (EDCs) designed to enhance performance.
These EDCs include Bisphenol A (BPA), used to improve the fabric’s lifespan or fix dyes, and Per- and Polyfluoroalkyl Substances (PFAS), applied for stain and water repellency in activewear. BPA is a known endocrine disruptor that mimics estrogen and has been detected in some synthetic athletic wear at levels exceeding safety limits. These chemicals can be absorbed through the skin, a process amplified when a person sweats, as increased skin permeability allows for greater uptake of chemical compounds.
The Risk of Microplastic Fiber Shedding
A significant concern related to polyester clothing is the shedding of microplastic fibers, which are tiny plastic particles less than five millimeters in length. Polyester releases these microfibers primarily during washing, but also during regular wear and tear. A single wash cycle can release hundreds of thousands of these microscopic plastic strands into the wastewater system.
While many fibers enter the environment, a considerable amount also becomes airborne, especially in indoor environments where synthetic textiles are prevalent. Inhaling these airborne microplastics presents a potential risk to respiratory health, as the fibers can embed themselves deep within lung tissue. The smallest fibers, or nanofibers, are believed to pose a greater risk because they can travel farther and penetrate deeper into tissues.
These physical microplastic particles also act as carriers for chemical additives used in the fabric, such as EDCs, which can be absorbed by the body upon contact or ingestion. The health concern is twofold: the physical presence of the plastic fiber and the toxic substances it transports. Research suggests that garments made from recycled polyester may shed up to 55% more microplastic particles than those made from virgin polyester, complicating the choice for environmentally conscious consumers.
Strategies for Minimizing Exposure and Choosing Safer Fabrics
Individuals concerned about the risks associated with polyester can adopt several practical strategies to minimize their exposure. The most direct approach is to prioritize natural, biodegradable fibers for clothing worn in direct contact with the skin. These materials, including organic cotton, linen, hemp, and wool, are less likely to shed microplastics and do not require the same array of chemical finishes as synthetic textiles.
For existing polyester garments, especially activewear, changes in laundry habits can reduce both chemical and microplastic release.
- Wash synthetic clothing less frequently.
- Use colder water.
- Ensure the washing machine is running a full load to minimize fiber shedding caused by friction.
- Use external washing machine filters or specialized microfiber-catching laundry bags to capture a significant portion of the fibers.
- Opt for undyed or lightly dyed fabrics to help reduce exposure to heavy metals and azo dyes.