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Thread Carefully: Your Gym Clothes Could Be Leaching Toxic Chemicals

If you are thinking of heading out on your daily run, walk or hike, have a read of how the chemicals in your clothing could be affecting your health and what you can do to prevent it. 

New research is indicating that when wearing gym clothes and any clothing containing artificially made plastic chemicals, our sweat is helping these harmful substances to absorb into our bodies through our skin. 

Even though the study mainly focused on flame retardant chemicals, which can be found in some fabrics and not just gym wear, the findings suggest that other plastic chemicals like bisphenols, phthalates and Per- and Polyfluorinated Substances (PFAs) which are prevalent in your workout gear, can leach from the clothes themselves and into our bodies via our sweat. 

In the past, research surrounding microplastics and the chemicals derived from plastic production have focused on how these are entering the body via the food that we consume. However, this study illustrates the absorbency of these chemicals and how they are entering into our bodies through our skin, as our sweat breaks down these substances more readily.  

It is understood that having a high number of plastic chemicals in our bodies can result in health risks. For example, a US study found the risk of cancer has increased in Americans under 50, with breast and thyroid cancers becoming some of the fastest rising. Experts have speculated that an increased exposure to harmful pollutants and chemicals such as the ones found in our clothing could be a major factor. 

So what chemicals should you be aware of? 

A lot of workout gear and clothing that specifically states that it is ‘sweat-wicking’ or water-repellent can often contain plastic chemicals, also known as ‘forever chemicals’. They have been given this name for the amount of time that they take to break down, the clue is in the name. 

You may have heard of PFAS? PFAS are a human-made chemical that you will encounter in everyday items such as your saucepans, firefighting foam, clothing, and even food packaging. The fact that they take a very long time to break down, means that they can stay in our bodies once absorbed for a long time and potentially do harm to us and the planet. Further studies need to be exercised in order for more conclusive research and long-term testing to be carried out. 

So what can you do? 

Now that you know a little more, it is important to understand how clothing manufacturers such as outdoor retailers and sportswear brands are not only marketing their products, but what they are putting into their clothing. Gore-Tex is a popular material used to show the technical features of certain clothing such as walking shoes. However, in reality, this is just another type of PFAS coating. 

If a clothing manufacturer boasts that their clothing is ‘sweat-wicking’, keep in mind that they may have used artificial PFAS chemicals within the fabric. 

With research indicating that there are many ‘forever chemicals’ out there that we are not aware of, it is difficult to avoid them fully. However, as consumers are becoming more ethically aware, some brands are straying away from using plastic chemicals and choosing a more sustainable approach. 

It is also worth taking a look at fabric labels to see if they have used ethically sourced and naturally derived materials such as cotton, bamboo and hemp. Arguably, this can be expensive, but as more brands are aware of consumer’s buying habits, and want to move away from harsh chemicals, we may see an increase in the uptake of more naturally sourced clothing material.

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Woman stretching on pavement - Image by lograstudio on Pixabay (ST ref: 1244)

Chemist holding vial  - Image by Bermix Studio on Unsplash (ST ref: 1226)


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