Safe swimsuits for your skin and your pool
When evaluating water quality or dermatological care during a swim, attention is usually focused exclusively on chlorine levels and the use of sunscreens. However, there is a silent element that drastically alters both the chemical balance of the water and the skin’s natural barrier: the composition of the fabrics entering the water.
The interaction between fabrics and the aquatic environment is a continuous chemical reaction. Below is a detailed look at how certain materials affect this closed ecosystem and what characteristics define a truly safe fabric for both environments.
The hidden reaction of dyes and chloramines
It is a common belief that skin redness and the strong “pool smell” are caused by an excess of chlorine. In reality, this is a byproduct of a chemical reaction.
When low-quality swimsuits, especially those with improperly set dyes, come into contact with treated water, chlorine attacks the dye molecules. This decomposition generates chloramines. Chloramines are volatile compounds that not only severely irritate the epidermis and eyes but also neutralize the water’s disinfecting power. A swimsuit with unstable dyes forces the water to consume its defensive chemicals simply to combat the fabric, leaving the skin exposed to bacteria.
The problem of elastane (Lycra/Spandex) degradation
For a swimsuit to be form-fitting, it requires high percentages of elastane. What is rarely mentioned is how this material behaves on a microscopic level under pH variations.
In water with a slightly elevated pH, elastane fibers experience accelerated degradation. As they break down, not only does the fabric lose its shape, but it also releases a microscopic sticky biofilm. This invisible substance floats to the edges and adheres to the ceramic or tiles, creating that dark, greasy ring at the waterline. At the same time, this decomposed film sticks to the skin’s pores, trapping body oils and causing acne breakouts or contact dermatitis.
Microplastics and filtration collapse
Swimsuits are composed almost entirely of plastic derivatives such as polyester and nylon. With water friction, these garments shed thousands of microfibers per hour.
- The impact on the water: Advanced filtration systems (such as diatomaceous earth or glass sand) are designed to trap particles the size of a red blood cell. Microplastics from swimsuits saturate these micropores. The result is water that loses its crystalline shine and becomes cloudy, as the choked filter cannot process other impurities.
- The impact on the skin: These floating microfibers act as microscopic abrasives that constantly rub against the skin, weakening its outer protective layer without being noticeable to the naked eye.
The washing mistake: Phosphates and algae food
A critical factor that introduces instability to the water comes from how swimsuits are treated outside of it. The use of fabric softeners on swimwear leaves chemical residues impregnated in the threads.
These softeners are rich in phosphates. In aquatic chemistry, phosphates are the main food source for algae spores. A single swimsuit washed with fabric softener can introduce enough phosphates to transform a crystalline aquatic environment into a cloudy, greenish ecosystem within hours under the sun. Additionally, softener residues trapped in the fabric block skin oxygenation, promoting heat rashes and irritation.
Criteria for a safe fabric
To maintain the integrity of the skin barrier and the purity of an aquatic system, garments must meet rigorous technical specifications:
- Pre-washed and solution-dyed fabrics: Colors must be integrated into the fiber before yarn extrusion, not superficially dyed afterward. This prevents the release of dyes and the formation of chloramines.
- PBT (Polybutylene Terephthalate) blends: This type of texturized polyester has extreme resistance to chemical oxidation. It does not break down, does not release sticky residues on the edges, and maintains its structural integrity without saturating filtration systems.
- Additive-free maintenance: The ideal garment is one that only requires rinsing with clean, cold water, without aggressive detergents or fabric softeners that introduce unwanted phosphates into the water ecosystem.
