It is possible to find untreated natural-fiber textiles, but you have to look carefully. Unless a product is labeled as untreated, you must assume that it has been chemically treated during the manufacturing and finishing processes.
Choosing natural fibers over synthetics for upholstery and other interior applications is a "natural" choice in a healthy home, but fibers such as cotton, linen, and wool are almost always treated with finishing chemicals to provide anti-wrinkling qualities, stain and water resistance, and flame retardance. Other chemicals are used in the dyeing process and as cleaning agents.
You mentioned formaldehyde, a volatile organic compound (VOC) and a known carcinogen. Although there are hundreds of VOCs associated with the textile manufacturing process, formaldehyde makes up the greatest proportion of the emissions. Formaldehyde is used in permanent press and stain resistance treatments, and as a solvent in the dyeing process.
When shopping for natural-fiber textiles for upholstery and window coverings, it?s best to choose materials grown without chemicals from the start, such as organic cotton, linen, hemp, bamboo, or wool. Next, you?ll want to be sure that the textile dyes are nontoxic. You'll be amazed by the range of beautiful, rich colors that can be obtained with natural, plant- and mineral-based dyes.
Finally, look for fabrics that were not chemically treated in the finishing process. You don?t need stain-proofing finishes to keep your textiles looking fresh and clean. Most natural fibers are innately stain resistant and can be spot-cleaned with water and baking soda, or a nontoxic cleaner. If you?re concerned about stains on upholstered furniture, I recommend having slipcovers made that can be removed for laundering.
You can find beautiful organic cotton velvet drapery from the Antique Drapery Rod Company, or organic hemp curtains from Rawganique. For upholstery, I suggest fabrics from Q Collection or Furnature. Furnature also offers a unique washing service for nonorganic fabrics to remove any chemicals that were applied in the manufacturing or finishing process.
Natural-fiber area rugs made from wool, hemp, and cotton are available untreated and made with natural dyes. I recommend area rugs instead of wall-to-wall carpeting because they?re easier to clean and you can move them around when redecorating. Wool carpeting from Nature?s Carpet or Earth Weave can be bound to any size. Natural Home Products offers a beautiful selection of handmade Tibetan-style rugs.