Control of felinine-derived malodor in cat litter.

OBJECTIVES: Malodors stemming from soiled cat litter are a major frustration for cat owners, despite the widespread use of absorbent litters with claims of odor control. Technologies for effective litter odor control have not been rigorously evaluated. Here, we report on the effectiveness of a novel litter formulation of 1-monochlorodimethylhydantoin (MCDMH)-modified clinoptilolite zeolite (MCDMH-Z) to control the odors of 3-mercapto-3-methylbutanol (3M3MB) and ammonia, the principal products generated by the enzymatic breakdown of felinine and urea, respectively. METHODS: The efficacy of MCDMH-Z for the odor control of 3M3MB was determined by solid-phase microextraction and gas chromatography mass spectrometry analysis, colorimetric analysis and a sensory panel. Enzyme inhibition was monitored by a colorimetric coupled assay for ammonia. The antimicrobial properties were measured by a reduction in colony-forming units (CFUs). RESULTS: 3M3MB proved highly susceptible to modification by MCDMH-Z granules. Headspace above litter exposed to MCDMH-Z showed no detectable 3M3MB; levels >59 ng were detected in commercially available products. Urease activity decreased by >97% after incubation with MCDMH-Z to 0.14 mg/ml. Cat litter F showed comparable inhibition (0.13 mg/ml); others showed less inhibition, producing up to 4.8 mg/ml of ammonia. MCDMH-Z reduced the CFUs of Proteus vulgaris by six log reduction values in 30 mins; in the same amount of time, no reduction was seen with commercial products tested. The odor control capability of the MCDMH-Z granules was further supported by a sensory panel scoring 3M3MB-spiked litters. CONCLUSIONS AND RELEVANCE: Samples of commercially available litter products showed an effect on malodor, or inhibition of urease, or contained antimicrobial activity; no samples were capable of accomplishing these concurrently. In contrast, MCDMH-Z granules were effective in all three test categories. Control of felinine-derived odors, in particular, has the potential to improve cat owner satisfaction, and may beneficially affect cat behaviors provoked by pheromonally active sulfurous metabolites deposited in the litter.

Temperature Sensitivity After Burn Injury: A Burn Model System National Database Hot Topic.

People living with burn injury often report temperature sensitivity. However, its epidemiology and associations with health-related quality of life (HRQOL) are unknown. We aimed to characterize temperature sensitivity and determine its impact on HRQOL to inform patient education after recovery from burn injury. We used the multicenter, longitudinal Burn Model System National Database to assess temperature sensitivity at 6, 12, and 24 months after burn injury. Chi-square and Kruskal-Wallis tests determined differences in patient and injury characteristics. Multivariable, multilevel generalized linear regression models determined the association of temperature sensitivity with Satisfaction with Life (SWL) scale scores and Veterans RAND 12 (VR-12) physical and mental health summary component (MCS) scores. The cohort comprised 637 participants. Two thirds (66%) experienced temperature sensitivity. They had larger burns (12% TBSA, interquartile range [IQR] 4-30 vs 5% TBSA, IQR 2-15; P < .0001), required more grafting (5% TBSA, IQR 1-19 vs 2% TBSA, IQR 0-6; P < .0001), and had higher intensity of pruritus at discharge (11% severe vs 5% severe; P = .002). After adjusting for confounding variables, temperature sensitivity was strongly associated with lower SWL (odds ratio [OR] -3.2, 95% confidence interval [CI] -5.2, -1.1) and MCS (OR -4.0, 95% CI -6.9, -1.2) at 6 months. Temperature sensitivity decreased over time (43% at discharge, 4% at 24 months) and was not associated with poorer HRQOL at 12 and 24 months. Temperature sensitivity is common after burn injury and associated with worse SWL and MCS during the first year after injury. However, temperature sensitivity seems to improve and be less intrusive over time.