What your everyday footwear could be doing to your feet—and why choosing better materials matters
Crocs have become one of the world's most recognisable shoes. Comfortable, lightweight, waterproof and easy to slip on, they've become a favourite for adults and children alike. But while comfort often drives our purchasing decisions, very few people stop to ask an important question: what exactly are our shoes made from, and what does that mean for our health?
As consumers become increasingly carbon-conscious, many are looking beyond style and convenience to consider the environmental and health impacts of the products they wear every day. Whether you wear Crocs or any other plastic-based footwear, understanding the materials beneath your feet is an important part of making informed choices. After all, our feet contain over 250,000 sweat glands, making them one of the most absorbent parts of the body, particularly when enclosed in warm footwear for long periods.
The Hidden Problem with Plastic Footwear
Not all plastic shoes are created equal
Most moulded clogs and sandals are made from synthetic polymers such as EVA (ethylene-vinyl acetate), PVC (polyvinyl chloride), polyurethane or proprietary foam blends. While these materials are inexpensive, durable and waterproof, the chemicals used during manufacturing can vary significantly between brands.
There are many inexpensive clogs, imitating well-known brands, and these are arguably worse due to them being made from PVC and have been found to contain high levels of phthalates and polycyclic aromatic hydrocarbons (PAHs), chemicals that have raised health concerns and are heavily regulated in children's products across Europe and North America (Consumer Council, 2014; Mandal et al., 2022).
Research has shown that plasticisers such as phthalates are not chemically bound to PVC, meaning they can gradually migrate out of products over time, particularly under higher temperatures or prolonged use (Mandal et al., 2022). While skin absorption from footwear alone is generally considered lower than other exposure routes, scientists recognise footwear as one potential contributor to overall chemical exposure (MDPI, 2016).
Plastic That Lasts Long After You Stop Wearing It
The environmental cost of synthetic footwear
While comfort is often the main selling point, it's equally important to consider what happens to plastic footwear at the end of its life. Most Crocs-style clogs and similar moulded shoes are made from synthetic polymers derived from fossil fuels. Although authentic Crocs use a proprietary closed-cell resin called Croslite™, it is not biodegradable, meaning discarded shoes can remain in the environment for decades or even centuries if they end up in landfill or the natural environment. Like many synthetic materials, they break down into increasingly smaller fragments rather than decomposing naturally, contributing to the growing problem of microplastic pollution (United Nations Environment Programme, 2023).
Because moulded plastic footwear is made from complex polymer blends, recycling can also be difficult, and many worn-out pairs ultimately become waste. Choosing footwear made from renewable materials such as natural rubber, cork, hemp, organic cotton or responsibly sourced leather supports a more carbon-conscious lifestyle and helps reduce our dependence on virgin plastics. Investing in durable, repairable shoes that align with the principles of circular fashion, ethical fashion and sustainable fashion is one of the simplest ways consumers can reduce their environmental footprint with every step.
Why Heat Makes a Difference
Warm feet can increase chemical migration
Our feet naturally become warm and sweaty, especially during summer, exercise or prolonged wear. Heat, moisture and friction can all increase the migration of certain chemicals from plastics and PVC materials.
Scientific reviews have demonstrated that elevated temperatures accelerate the movement of phthalates from plastic materials, increasing the potential for human exposure (Mandal et al., 2022).
Children deserve particular attention because their skin is more delicate, their bodies are still developing, and they experience greater exposure relative to their body weight. For this reason, governments around the world have introduced strict regulations limiting phthalates in children's products due to concerns over endocrine disruption and reproductive toxicity (Kim et al., 2020; Lee et al., 2021).
The safest approach is not necessarily avoiding one particular brand, but choosing footwear made from well-regulated, transparent materials rather than unknown plastics.
More Than Chemicals: Your Feet Need Better Support
Comfort isn't always the same as healthy footwear
Beyond material concerns, footwear design also matters.
Many podiatrists advise against wearing loose-fitting foam clogs for extended periods because they often provide limited arch support, heel stability and foot control. Relying on them as an everyday shoe may contribute to fatigue, instability and altered walking patterns for some people.
Children are especially vulnerable because their feet continue developing throughout childhood. Shoes that encourage the toes to grip constantly in order to stay on the foot may not provide the stable support needed during periods of rapid growth. Supportive footwear is recommended for school, sports and long periods of walking.
Choosing shoes that fit securely, allow natural toe movement and support healthy biomechanics benefits both comfort and long-term foot health.
Better Alternatives for Your Feet—and the Planet
Natural materials support healthier choices
If you're looking to reduce both your environmental footprint and your exposure to unnecessary synthetic materials, there are excellent alternatives available.
Look for footwear made from:
Natural cork footbeds
Organic cotton uppers
Hemp textiles
Responsibly sourced natural rubber
FSC-certified wood
Plant-based or vegan leather alternatives
Recycled natural fibres
These materials not only reduce reliance on virgin plastics but also align with the principles of ethical fashion, circular fashion and sustainable fashion. Many brands are now designing shoes that prioritise durability, repairability and recyclable materials—helping consumers reduce waste while investing in products built to last.
The most sustainable shoe is often one that combines quality craftsmanship, responsibly sourced materials and a lifespan measured in years rather than seasons.
Choose Footwear That Works for You—and the Planet
Every purchase we make is a small vote for the kind of future we want. This conversation highlights a big current-day issue: understanding what our footwear is made from, how it's produced and how it affects both our health and the environment.
As more people embrace carbon-conscious living, choosing high-quality footwear made from natural, responsibly sourced materials becomes part of a wider commitment to healthier lifestyles and a healthier planet.
If you're ready to explore footwear that aligns with the values of sustainable fashion, ethical fashion, vegan innovation and circular fashion, visit The Carbon Closet. As a dedicated sustainable fashion platform, we carefully curate brands that prioritise responsible materials, transparency and environmental impact—making it easier to find shoes that are better for your feet, your family and the future.