===Processing===
Cocoons are soaked in [[sodium carbonate]] to soften in preparation for reeling (unwinding the filament from the cocoon). Silk fabric is then woven with the natural gum or [[sericin]] still on the yarn, acting as a natural sizing agent. There are several reported cases of allergies to silk, although these have been traced to the remnants of sericin in the finished product. After weaving, the gum is removed by boiling the fabric in alkali. This can result in a 20% reduction of the harvested weight of the silk. Some of this lost weight is added back by saturating the silk fabric in a bath of tin-phosphate-silicate salts. These processes can create a high biological load on the water, and deplete available oxygen for aquatic species if left untreated. Exposure to tin through breathing and skin contact can have acute and long-term effects on worker health if proper equipment is not used.[6]
<br/>Lightweight silk fabrics (fine gauge silk) are prone to wear and are degraded by exposure to sunlight and hot temperatures. They can also be susceptible to abrasion and twisting in laundering.[7]