A Laboratory Method for Determining Bacterially Formed Odorants and Reducing Odor in Absorbent Incontinence Products.

PURPOSE: The purpose of this study was to design a laboratory test method to mimic the formation of bacterially formed odorants during the use of absorbent urinary incontinence products. Three odor inhibitors with different modes of action were tested and evaluated. METHODS: Bacterially formed odorants in incontinence products were evaluated by adding a synthetic urine inoculated with a mixture of 4 bacterial strains to product samples cut from the incontinence products. The product samples were incubated in sealed flasks. The odorants that formed in the head space were sampled onto adsorbent tubes and analyzed by gas chromatography. The inhibitory effects of low pH, ethylenediaminetetraacetic acid (EDTA), and activated carbon were then measured. RESULTS: This technique enabled production of known odorants 3-methylbutanal, guaiacol, diacetyl, and dimethyl disulfide (DMDS) in concentrations of 50 to 600 ng/L in incontinence products. The method was further evaluated by testing 3 types of odor inhibitors; EDTA significantly reduced formation of all 4 odorants (P < .001). Lowering the pH from 6.0 to 4.9 decreased levels of 3-methylbutanal, DMDS, and guaiacol (P < .001); however, diacetyl levels increased (P < .001). Activated carbon significantly reduced the formation of diacetyl, DMDS, guaiacol, and 3-methylbutanal (P < .001). CONCLUSIONS: The technique we developed can be used to evaluate inhibitors with different modes of action to determine odor control in incontinence products. The odorants formed are produced by bacteria and have been identified as key contributors to the odor of used incontinence products. This work can be a step toward establishing a standard in the field of incontinence and odor control; creation of a standard will help the health care sector compare products to be purchased and benefit patients through the development of better products.

Sensory Characterization of Odors in Used Disposable Absorbent Incontinence Products.

PURPOSE: The objectives of this study were to characterize the odors of used incontinence products by descriptive analysis and to define attributes to be used in the analysis. A further objective was to investigate to what extent the odor profiles of used incontinence products differed from each other and, if possible, to group these profiles into classes. SUBJECTS AND SETTING: Used incontinence products were collected from 14 residents with urinary incontinence living in geriatric nursing homes in the Gothenburg area, Sweden. METHODS: Pieces were cut from the wet area of used incontinence products. They were placed in glass bottles and kept frozen until odor analysis was completed. A trained panel consisting of 8 judges experienced in this area of investigation defined terminology for odor attributes. The intensities of these attributes in the used products were determined by descriptive odor analysis. Data were analyzed both by analysis of variance (ANOVA) followed by the Tukey post hoc test and by principal component analysis and cluster analysis. RESULTS: An odor wheel, with 10 descriptive attributes, was developed. The total odor intensity, and the intensities of the attributes, varied considerably between different, used incontinence products. The typical odors varied from "sweetish" to "urinal," "ammonia," and "smoked." Cluster analysis showed that the used products, based on the quantitative odor data, could be divided into 5 odor classes with different profiles. CONCLUSIONS: The used products varied considerably in odor character and intensity. Findings suggest that odors in used absorptive products are caused by different types of compounds that may vary in concentration.

Identification of Key Odorants in Used Disposable Absorbent Incontinence Products.

PURPOSE: The purpose of this study was to identify key odorants in used disposable absorbent incontinence products. DESIGN: Descriptive in vitro study SUBJECTS AND SETTING:: Samples of used incontinence products were collected from 8 residents with urinary incontinence living in geriatric nursing homes in the Gothenburg area of Sweden. Products were chosen from a larger set of products that had previously been characterized by descriptive odor analysis. METHODS: Pieces of the used incontinence products were cut from the wet area, placed in glass bottles, and kept frozen until dynamic headspace sampling of volatile compounds was completed. Gas chromatography-olfactometry was used to identify which compounds contributed most to the odors in the samples. Compounds were identified by gas chromatography-mass spectrometry. RESULTS: Twenty-eight volatiles were found to be key odorants in the used incontinence products. Twenty-six were successfully identified. They belonged to the following classes of chemical compounds: aldehydes (6); amines (1); aromatics (3); isothiocyanates (1); heterocyclics (2); ketones (6); sulfur compounds (6); and terpenes (1). CONCLUSION: Nine of the 28 key odorants were considered to be of particular importance to the odor of the used incontinence products: 3-methylbutanal, trimethylamine, cresol, guaiacol, 4,5-dimethylthiazole-S-oxide, diacetyl, dimethyl trisulfide, 5-methylthio-4-penten-2-ol, and an unidentified compound.

Method for Bacterial Growth and Ammonia Production and Effect of Inhibitory Substances in Disposable Absorbent Hygiene Products.

PURPOSE: The purpose of this study was to evaluate a pragmatic laboratory method to provide a technique for developing incontinence products better able to reduce malodor when used in the clinical setting. METHODS: Bacterial growth and bacterially formed ammonia in disposable absorbent incontinence products was measured by adding synthetic urine inoculated with bacteria to test samples cut from the crotch area of the product. The inhibitory effect's of low pH (4.5 and 4.9) and 3 antimicrobial substances-chlorhexidine, polyhexamethylene biguanide (PHMB), and thymol-at 2 concentrations each, were studied. RESULTS: From the initial inocula of 3.3 log colony-forming units per milliliter (cfu/mL) at baseline, the bacterial growth of the references increased to 5.0 to 6.0 log cfu/mL at 6 hours for Escherichia coli, Proteus mirabilis, and Enterococcus faecalis. At 12 hours there was a further increase to 7.0 to 8.9 log cfu/mL. Adjusting the pH of the superabsorbent in the incontinence product from 6.0 to pH 4.5 and pH 4.9 significantly (P < .05) inhibited the bacterial growth rates, in most cases, both at 6 and 12 hours. The effect was most pronounced at pH 4.5. Chlorhexidine had significant (P < .05) inhibitory effect on E. coli and E. faecalis, and at 12 hours also on P. mirabilis. For PHMB and thymol the results varied. At 6 hours, the ammonia concentration in the references (pH 6.0) was 200 to 300 ppm and it was 1500 to 1600 ppm at 8 hours. At pH 4.5, no or little ammonia production was measured at 6 and 8 hours. At pH 4.9, there was a significant reduction (P < .01). Chlorhexidine and PHMB exerted a significant (P < .01 or P < .001) inhibitory effect on ammonia production at both concentrations and at 6 and 8 hours. Thymol 0.003% and 0.03% showed inhibitory effect at both 6 hours (P < .01 or P < .001) and at 8 hours (P < .05 or P < .001). CONCLUSION: The method described in this study can be used to compare the ability of various disposable absorbent products to inhibit bacterial growth and ammonia production. This technique, we describe, provides a pragmatic method for assessing the odor-inhibiting capacity of specific incontinence products.

Lactobacillus fermentum Ess-1 with unique growth inhibition of vulvo-vaginal candidiasis pathogens.

The aim of this study was to characterize human isolates of Lactobacillus species for their capacity to interfere with the growth of different strains of Candida species in vitro in the search for a potential probiotic. Growth inhibition of Candida species was screened using an agar-overlay method. Inhibiting strains were selected to assay the effect of a cell-free Lactobacillus culture filtrate (LCF) on the growth of isolates of Candida albicans and Candida glabrata. A total of 126 human Lactobacillus isolates was investigated. Eighteen isolates significantly inhibited the growth of C. albicans on agar. The LCF of one of these strains showed strong inhibition of both C. albicans and C. glabrata. This strain was genetically identified as Lactobacillus fermentum and designated L. fermentum Ess-1. Further tests to evaluate the probiotic potential of this strain indicated that L. fermentum Ess-1 strain is a promising probiotic for use in clinical trials to treat and prevent vulvo-vaginal candidiasis.

Lactobacilli in the female genital tract in relation to other genital microbes and vaginal pH.

BACKGROUND: The relationship between lactobacilli and other microbes and the association with vaginal pH in the female genital tract were examined. The study also included evaluation of the possibility of supplying probiotics to the genital tract by using panty liners impregnated with the probiotic strain Lactobacillus plantarum LB931. METHODS: This was a randomized, placebo-controlled, double-blind, multicenter study involving 191 healthy fertile women. Specified microbes were counted and vaginal pH was measured once a month for five consecutive months. RESULTS: Major individual variations in the genital microflora composition and the vaginal pH were found among the women. The number of lactobacilli was significantly related to vaginal pH (p<0.001) and approximately 70% of the women were permanent carriers of individual lactobacilli strains. Women with high numbers of lactobacilli were less prevalent with Group B streptococci than women with low numbers (p=0.036), and these women had a lower mean vaginal pH. The number of lactobacilli also correlated with the prevalence of yeast. LB931 could be found in 86% of the labial samples and 54% of the vaginal samples. CONCLUSIONS: High numbers of lactobacilli may contribute to a low vaginal pH and seem to have a negative influence on Group B streptococci. LB931 could be transferred from the panty liners to both the vagina and the labial fold.

The vulvar skin microenvironment: impact of tight-fitting underwear on microclimate, pH and microflora.

The aim of the present study was to investigate if tight-fitting underwear (string panties) equipped with string panty liners affected the vulvar skin microenvironment differently to regular panties with standard panty liners. Thirty-two healthy women participated in a crossover study where temperature, humidity, surface pH and aerobic microflora were measured on vulvar skin. Vulvar skin temperature was 35.2 +/- 0.19 (mean +/- SEM) and 35.3 +/- 0.17 degrees C, respectively, for the two underwear systems. Mean humidity and mean skin surface pH at vulvar skin did not differ between the two systems. Barely noticeable differences were found for the aerobic microflora both at labium majus and at perineum. The mean total number of microorganisms in the two different panty liners was the same, 6.0 +/- 0.15 and 6.0 +/- 0.16, respectively (log CFU per panty liner). The differences in panty and panty liner design studied seem to have negligible impact on the vulvar skin microclimate, skin surface pH and aerobic microflora. No support was found for the assumption that a string panty system would result in higher contamination of vulvar skin by anorectal microflora.

The vulvar skin microenvironment: influence of different panty liners on temperature, pH and microflora.

The aim of this study was to confirm findings that vapour-impermeable panty liners might impair skin climate, and to assess their impact on the skin microflora. Temperature, surface pH and aerobic microflora were measured on vulvar skin of 102 women. The mean skin temperature was 1.1 degrees C higher when using a vapour-impermeable panty liner compared with not using one. Use of panty liners with vapour-permeable back sheets and acidic cores resulted in skin temperature, pH and microflora levels that were very close to those observed in persons not using liners. The temperature, pH and total number of microorganisms were significantly lower for users of vapour-permeable panty liners than for users of vapour-impermeable ones (p <0.05, p<0.001 and p<0.001, respectively). The microorganism densities were usually higher when using the vapour-impermeable panty liner, but mean differences were minor. The use of panty liners seems not to imply a microbial risk for normal, healthy women.