Odors - Unseen
In recent years there's been a profusion of lesser quality, odorous area rugs that have appeared in the consumer marketplace. Most of these are hand-tufted rugs from the Asian subcontinent, particularly imported from India, Pakistan or China. One of the common problems with these rugs is a tenacious unpleasant odor that emanates from the latex back coating or adhesive, which is a part of the carpet construction. Unfortunately, this foul odor is "built in" and no amount of professional cleaning or deodorization will permanently remove it. New rugs should never smell this way and good old rugs seldom do either.
The odor can vary from mild to strong and oppressive. One characteristic smell typical of these rugs is of "diesel fuel" or "burnt" oily type residues coming out of the latex. But other odors such as “curry” and more are possible. These rugs may even smell bad right in the store, but the odor appears more concentrated and noticeable in the smaller rooms and spaces of your home. The mass market importers often sell these shoddy rugs, and this foul condition is a defect in the rug from manufacture and distribution
Area rugs with this foul odor problem are usually hand tufted. The pile fiber is usually wool but it also could be acrylic, cotton, olefin or others. This construction has the pile inserted through a primary backing and latex "glue" or adhesive is applied to the underside of the backing fabric to help secure the pile yarns in place. Also, this same latex adhesive is used to glue or adhere the secondary backing fabric to the rest of the rug. The secondary backing fabric—usually a coarse cotton duck fabric and often dyed green, blue or other colors—is what you would see when looking at the back or underside of the rug.
We believe the odor is caused by defective, low quality latex adhesive used at the time of rug manufacture. There may be diesel oil odors absorbed into the latex during shipboard transport from India, or the odors used to cover up other problems. Or some odorous microbial degradation or musty deterioration of the latex may be occurring, even when the rug is brand new. When cleaning the carpet to remove stains and soiling, or in attempts to eliminate the oppressive odor, the carpet is often customarily wet cleaned. It's possible that during or after any normal and safe process of wet cleaning or in-plant rug cleaning, one may notice an accentuated foul latex odor. This is not a result of the cleaning but a continuing degradation and off-gassing of odorous components from the latex adhesive in the carpet. The cleaning industry's best experience is that this offensive odor cannot be permanently removed, and may or may not be temporarily alleviated.
In addition, there are discolorations and dye transfer problems associated with Indian or lesser quality Asian area rugs that further compound their defective nature. When these area rugs with dyed backing are placed on top of light color carpet, the poorly dyed cotton scrim or canvas backing fabric may "crock" or transfer its green, blue or other offensive color onto the carpet or rug underneath. During wet cleaning, fugitive dye markers used to stencil the pattern for hand tufting can bleed up to the surface of the rug pile. With cotton hooked rugs, discoloration from cellulosic browning can occur during cleaning and drying. In addition, some of the darker colors can bleed during cleaning. None of these offensive conditions should ever occur with a well-made Oriental or area rug. As we noted above, in our professional opinion, rugs with persistent foul odor, dye transfer, discoloration or color bleeding are fundamentally defective and should be returned to the retailer for adjustment or replacement.