Phthalates in sportswear: the hidden plasticizers disrupting your hormones

Phthalates are plasticizers often added to plastics to make them flexible and soft. They are widely used in sportswear, shoes, and accessories containing PVC or other synthetic materials. It is now clear that phthalates are endocrine-disrupting chemicals that affect fertility, development, and metabolism. Despite increasing concern, phthalates in textiles are not yet banned everywhere. This means your sportswear can daily contain substances harmful to your health and the planet.

What are phthalates?

Phthalates are a group of chemical compounds used as plasticizers. They make plastics like PVC flexible, transparent, and durable. These substances are not chemically bound to the material, making them easily released during use or washing, and subsequently entering the environment.^[1] There are over 25 different phthalates in commercial use, each with varying applications and toxicity profiles.^[2]

The most common phthalates in consumer products are DEHP (di-2-ethylhexyl phthalate), DBP (dibutyl phthalate), BBP (benzyl butyl phthalate), and DINP (diisononyl phthalate).^[3]

Where are phthalates found?

Although there are increasing restrictions, phthalates are still found in:

Textiles and sportswear: especially in synthetic fabrics, prints, and coatings, such as logos, glossy layers, and water-repellent finishes.^[4] One study found phthalates in 83% of tested garments with plastisol prints (the glossy prints on T-shirts).^[5]

Shoes and accessories: athletic shoes, yoga mats, and raincoats often contain phthalates in PVC or synthetic leather.^[6] Research shows that phthalates migrate from yoga mats to the skin during use, particularly at elevated body temperatures during exercise.^[7]

Consumer products: toys, food packaging, shower curtains, and cosmetics. One study found that people who regularly use fragranced products had 2.5 times higher phthalate levels in their urine.^[8]

Medical products: IV tubing, blood bags, and catheters. Patients in intensive care may have significantly increased phthalate exposure from medical devices.^[9]

Environment and food chain: phthalates are found globally in water, soil, dust, and even in human blood and urine.^[10] Biomonitoring studies show that over 95% of the US population has detectable phthalate levels in their bodies.^[1]

Why are phthalates in sportswear?

Brands add phthalates to clothing and sports equipment for several reasons:

Flexibility and softness: makes plastics supple and comfortable. Without phthalates, many PVC-based materials would be stiff and brittle.

Prints and coatings: ensures that prints and glossy logos remain flexible without cracking or peeling. Plastisol prints—the most common printing technique for sportswear—often contain high concentrations of phthalates.^[5]

Water-repellent and durable: used in certain finishes that make sportswear more hard-wearing. Some water-repellent coatings use phthalates in addition to or instead of PFAS.

The problem: phthalates are released when worn, perspired in, and washed—and thus end up on your skin and in the environment. Studies show that phthalates from clothing can migrate into sweat and be absorbed through the skin, especially at elevated temperatures during exercise.^[11]

The health risks

Endocrine-disrupting effect

Phthalates are known endocrine disruptors. They affect the function of estrogen and testosterone and can lead to hormonal imbalances.^[12] The World Health Organization (WHO) classifies certain phthalates as endocrine-disrupting chemicals with proven effects on the reproductive system.^[13]

Fertility and development

Research shows that phthalates reduce fertility in men and women, can disrupt puberty, and affect fetal development.^[14] A systematic review found robust evidence that DEHP and DBP are associated with reduced sperm quality and lower testosterone levels.^[15]

In women, phthalate exposure has been linked to longer time to pregnancy, preterm birth, and reduced IVF success rates.^[16] Prenatal exposure is associated with genital abnormalities in boys and disrupted reproductive development.^[17]

Metabolic diseases

Exposure to phthalates is associated with obesity, insulin resistance, and an increased risk of type 2 diabetes.^[18] A meta-analysis found consistent associations between phthalate exposure and an increased risk of metabolic disorders, including metabolic syndrome.^[19]

Cancer and chronic diseases

Some phthalates are linked to an increased risk of breast cancer, liver problems, and asthma.^[20] Studies show that children with higher phthalate exposure significantly more often develop asthma and allergies.^[21]

Neurological development

Prenatal exposure to phthalates is associated with reduced cognitive development, behavioral problems, and reduced attention span in children.^[22]

Environmental impact

Because phthalates are not strongly bound to the material, they are released during production, washing, and disposal of textiles. They are found in rivers, oceans, and agricultural land and accumulate in animals and humans. This makes phthalates a persistent problem for ecosystems worldwide.^[4]

Research shows that one wash of phthalate-containing clothing can release up to 15 micrograms of phthalates into wastewater.^[23] Wastewater treatment plants do not completely remove phthalates, leading to their release into surface waters where they are harmful to aquatic organisms.^[24]

Maximum permitted quantities

EU: Since 2020, there has been a restriction on four widely used phthalates (DEHP, DBP, BBP, and DIBP) in consumer products. In products containing textiles or coatings, the concentration must not exceed 0.1% for each individual phthalate.^[6]

US: The Consumer Product Safety Commission (CPSC) bans certain phthalates in toys and children's products (maximum 0.1%), but not in adult clothing.^[25]

Canada: Bans phthalates in children's products above 1000 mg/kg (0.1%), but sportswear for adults is not always covered.^[26]

Are phthalates in sportswear tested?

Laboratories can detect phthalates in textiles using GC-MS (gas chromatography-mass spectrometry) and other analytical methods. OEKO-TEX® Standard 100 prohibits the use of many phthalates. Clothing with this label should be phthalate-free.^[27] GOTS (Global Organic Textile Standard) also prohibits phthalates in inks, prints, and all chemical inputs during production.

However, regulations do not mandate standard tests for sportswear, meaning consumers often do not know if their clothing contains phthalates. A 2021 consumer study found that 68% of tested sportswear with prints contained detectable phthalate levels.^[28]

How GOTS and OEKO-TEX protect against phthalates

Phthalates – the endocrine-disrupting plasticizers we just discussed – are exactly what GOTS and OEKO-TEX Standard 100 protect against. These certifications offer different but complementary protection.

The difference in approach: GOTS completely prohibits phthalates during the production process and only certifies natural fibers that do not require plasticizers, while OEKO-TEX 100 tests the final product to ensure that phthalate residues remain below safe limits. For organic cotton sportswear with both certifications, this means absolute certainty: no phthalates during production and a tested final product.

Contradiction: banned in children's toys, not in clothing

While phthalates in toys are strictly regulated due to concerns about children putting toys in their mouths, they remain permitted in many clothing and sports items. This is ironic: clothing is often worn directly on the skin for hours, with significantly higher skin absorption at elevated temperatures during exercise – potentially greater exposure than from brief toy use.

The logic behind this double standard is questionable, especially given research showing that dermal absorption of phthalates from clothing can be significant.^[11]

Conclusion

Phthalates may seem like a practical solution for flexible, water-repellent, and printed sportswear, but in reality, they are an invisible threat. They disrupt hormones, threaten fertility, increase the risk of metabolic diseases, and pollute ecosystems. The science is clear: the risks are too great to ignore.

At NOHI NATURAL, we therefore consciously choose GOTS-certified organic cotton and OEKO-TEX® STANDARD 100 certification. GOTS guarantees that the entire production chain – from raw material to finished product – is free of phthalates and other harmful chemicals. OEKO-TEX® STANDARD 100 tests the final product for over 1,000 harmful substances, including all relevant phthalates.

Organic cotton naturally does not need plasticizers – it is inherently soft, flexible, and comfortable. No PVC, no plastisol prints, no hidden chemicals. Only natural fibers that are safe for you and the planet. Because true health begins with what you wear and the choices you make for the earth.