Newsroom > Treating and remediation of urine stains

 

The problem with urine on textiles — especially carpets — is twofold:

First, if the urine is allowed to sit, it will develop a putrid odor from microbial action or natural oxidation, and especially on areas where it has been repeated voided.

The second problem is the staining due to the coloring pigments present naturally in urine or from the bacterial or fungal growth associated with these areas.

Deodorization
Urea is an excellent culture medium in which microorganisms grow with great rapidity. The bacteria can either be coccid or bacilli.

One of the changes that occur when urine is allowed to remain at room temperature is a variable increase in pH secondary to proliferation of unease producing bacterial contaminants and escape of carbon dioxide from urine.

Acidifying the affected area will slow down the action of bacteria and help dissolution of the urine salts. The real dose of a wide variety of bacteria comes from the environment into which the urine is deposited.

Skin scales, old urine deposits, dirt, and other organic and inorganic materials in indoor environments are teeming with all kinds of bacteria.

Your weapons are cleaning with a slightly acid cleaner and very good deep extraction, bacterial microorganisms, germicides, durable antimicrobial treatments, and the transient fragrance deodorizers.

None of these is magic and how you identify the problem areas and use these tools "smells" success or failure. Equally important is to try to understand your customer's expectations.

Some germicides work better than others.

Old stains
If urine on the textile like carpet is promptly tended to by spray extracting, the problems associated with odor and staining will not occur. However, in real life situations this is not the case, usually pets tend to pick a spot and frequent that area repeatedly, but they may also void all over the area.

Most times this goes unnoticed and the voided urine just sits there. Some pet owners may not notice the odor problem as their sense of smell becomes desensitized.

If the pet is removed from the area and the urine dries, the smell may not be discernible, in such situations the odor can come back after the carpet becomes wet, for instance, from cleaning.

Continuously voided urine over the same area of the carpet will impregnate not only the backing but also the carpet fibers and could also damage the sub-flooring, especially if it was wood, unsealed concrete, or similar material and may make it difficult to deodorize.

One method of treating is based on the fact that when urine is preserved with antibacterial agents like formaldehyde or thymol, it will not develop odor.

· First it is best to flush and remove as much urine as practically possible.

· Then acidification before application of germicide is helpful as it retards bacterial action.

· The contaminated area is then treated with an appropriate germicide containing a suitable perfume. The germicides can be oxidizers, iodophors, phenolics, quaternaries (quats).

Some germicides work better than others. The germicide must be compatible with area to be treated.

The germicide kills the odor causing bacteria and the perfume act as a masking agent. Depending on how badly the area is contaminated by the urine the padding and backing of carpet must be treated by direct application or needle injection, a second or third application may be necessary.

Use of the durable chemically reactive silane quaternary ammonium treatment provides longer-term control of offending bacteria, yeast, or fungus.

Before taking on a deodorizing job it is important to keep in mind that the cost of odor control should not exceed the cost of replacement.

Bacterial deodorization
Another approach is based on the natural decomposition of urine in soil, where naturally occurring bacteria is able to degrade the urine. This is done by seeding and inoculating the area with non-pathogenic bacterial cultures (incorrectly called enzymes).

The logic being that the introduced bacteria will rapidly consume the food source in urine and hence consume the source of odors. In such cases the area must be kept moist and warm for this approach to be affective for 24-48 hours and maintaining within a narrow pH range.

The success of deodorization will depend on holding these conditions, conditions difficult to sustain on carpet in the field. These are the same conditions that promote mold growth.

For low levels of urine contamination this approach can conceivably work, but for heavy contamination the abatement of odor will be difficult.

Aziz Ullah, Ph.D., MBA is president of Fabpro Manufacturing, is a leading formulator of scientifically engineered carpet and upholstery cleaning products. He is a member of the American Chemical Society, senior member of the American Association of Textile Chemists and Colorists, member of The Textile Institute (UK), and formulator of Butler Maximum Products.

W.Curtis White Ph.D. Director of R&D Aegis Environments-Midland, MI. Curt White is a microbiologist with advanced degrees in biochemistry (Wayne State University) and microbiology (Central Michigan University). He is an antimicrobials expert with 37 years of experience in the laboratory and field development and use of antimicrobials. He is an active member of ASTM, AATCC, ASM, SIM, APHA, AWWA and ASCR. Besides leading the commercialization efforts of his company's unique Aegis Microbe Shield Program, Curt is a widely recognized expert and consultant on the diagnosis, solving, and prevention of microbial problems of substrates and indoor environments.

From the May 2002 edition of Cleanfax magazine. For a free introductory subscription, click here.

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