This post originally appeared on Tortoise and Lady Grey, a fashion and lifestyle blog which aims to promote ethical and sustainable wardrobe choices, and inspire readers to embrace a slow fashion lifestyle. Polyester is cheap and versatile and for that reason it has become ubiquitous in fashion, but the environmental impacts of polyester are also significant. Before we delve into the environmental impacts of this textile, it is worth discussing it’s characteristics to understand why it is such a popular choice in fashion. Polyester is frequently used for its wrinkle-free properties. Clothing made from this textile tend not to need to be ironed or pressed to maintain their shape and surface. Because it often doesn’t need to be ironed and it can be washed easily in the washing machine, it is very convenient for the wearer to maintain. It also tends to be quick drying which is useful in places that have long periods of cold or wet weather. High quality polyester lasts well and maintains the quality of it’s surface. However, the great majority of polyester on the market is very poor quality and it used by manufacturers because it is a cheap alternative to natural fibres. Most polyester clothing on the market is cheap, poor quality fast fashion, which will last few wears. Polyester is a synthetic petroleum-based fibre, and is therefore made from a carbon-intensive non-renewable resource. Petroleum products are used as feedstock (raw material to make the fibre) and also used to generate the energy needed to manufacture. More than 70 billion barrels of oil are used to make polyester each year. It is not bio-degradable and will persist in the eco-system even as it eventually breaks apart. In fact, it is believed that synthetic garments are the biggest source of microplastic pollution in the oceans because up to 1900 fibres can be washed off one garment every time it is washed. Although it is less energy intensive than nylon to produce, it still requires more than double the energy of conventional cotton to produce. The production of polyester uses harmful chemicals, including carcinogens, and if emitted to water and air untreated, can cause significant environmental damage. Most polyester is produced in countries such as China, Indonesia and Bangladesh where environmental regulations are lax, and air and water pollution is often discharged untreated, resulting in significant pollution and harm to communities in the vicinity of (as well as downstream and downwind of) manufacturing plants. The water-intensity of production is much lower than for natural fibres. However, polyester cannot be dyed using low impact and natural dyes. This means that the detrimental impact on water supplies is potentially far greater. Read the rest on Tortoise and Lady Grey.