First of all, you should know that it’s a lot easier to find a sustainable t-shirt or hoodie than it is a sustainable suit.
That’s because our swimmers need to repel water, so they can’t be made from cotton, hemp, or any other plant-based fabric that will absorb moisture (though a few small designers are now experimenting with crochet suits made from natural yarns.)
Instead, swimsuits are often made from nylon (also known as polyamide) or polyester—two of the worst fabrics for the environment due to the amount of water, chemicals, and energy that goes into them, and their lack of biodegradability.
These synthetic fibers also leech tiny pieces of microplastics when they are agitated or come in contact with water (so, anytime we go for a swim or do laundry).
Microplastics can now be found throughout our oceans and while their long-term effects on aquatic life are unknown, “the plastic becomes a platform for concentrated pollutants, which would otherwise be diluted in the water” marine microplastics researcher Dimitri Deheyn, Ph.D. previously told mbg of their potential risks.
Barring some major innovations, our swimsuits are going to shed plastic for the foreseeable future. In the meantime, we can at least opt for ones made from recycled materials.
Synthetic, moisture-friendly fabrics can either be made from virgin (new) petroleum-based materials or ones that already exist and have been broken down and spun into yarn. Recycled yard cuts down on the need for raw materials to be extracted from the earth and, depending on where their plastic material is retrieved from, they keep plastic waste out of the landfill or ocean.
These two recycled fabrics are the most common in swimwear: