First, a little back story on silkworms:
They spin their own silk cocoons and the cocoon...along with the worm inside are boiled.
Because the silkworm moths have lost the ability to fly from domestication, silkworms can no longer exist in the wild and now depend on silk producers and laboratories to propagate the species.
So back to the question, is silk sustainable? Sort of.
Is it environmentally friendly? Yes, considering that silk fibers do break down whereas synthetic fibers end up in the ocean and in the stomachs of marine life.
Is it harmful to the silkworm? Yes, the worm is boiled inside its cocoon. Some cocoons are reserved so they can grow into moths.
Here are a few alternatives to look for the next time you have an eye on some silk swag.
Whilst normal silk boils silkworms alive in their cocoons Peace Silk, also known as Ahimsa Silk, allows the silkworm to emerge out of the cocoon naturally. Fibers from the damaged cocoon are spun together forming a silk which has the same luxurious feel of silk, with a slightly ‘raw’ appearance.
From a manufacturer's perspective, it’s hard to justify using this kind of silk, because the silk strands tend to get damaged easily. Quality control issues can create inconsistencies and blemishes in production. The damaged cocoons yield six times less filament, too – so no wonder the price of this silk is around double that of conventional silk.
Using the characteristics of strength and durability from spider silk, Bolt Threads has developed a spider-like silk using advanced technology. The principal ingredients are yeast, water, and sugar. The raw silk is produced through fermentation, much like brewing beer, except instead of the yeast turning the sugar into alcohol, they turn it into the raw stuff of spider silk. Bolt Threads spins that into threads using a method similar to the wet-spinning process used to create cellulose-based fibers such as Lyocell. It is molecularly the same as natural spider silk, with the exception of a few small variations.
Ramie is a flowering plant, and once the flowers begin to bloom, that is when the fibers are extracted from the plant for spinning, it can be harvested up to 6 times in a successful year.
Ramie is a highly sustainable eco-friendly fiber. It is very strong and durable and is 8 times stronger than cotton and even stronger when wet. It is naturally resistant to bacteria, mold, and mildew as well as light damage, rot or insect attack. It does not require pesticides or herbicides to grow healthily.