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Lightening in a bottle: comparison of ultraviolet light to traditional sterilization in saline irrigations bottles
Qasim Husain1, Catherine Banks1, Bradford A Woodworth2
1Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA.
Background:
Nasal saline irrigations (NSIs) are commonplace in treatment of patients with sinonasal disorders. Contamination of both the water source and delivery bottle remains a challenge with this therapy. The goal of this study was to optimize a disinfection technique with various methods of preparation, disinfection, and delivery of NSIs.
Methods:
Distilled and tap water sources in NSI bottles were contaminated by 4 bacterial strains: Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, and Legionella pneumophila. Contaminated bottles were cleaned with tap water, tap water with detergent, or microwave and swabbed for culture. Water-source disinfection was performed with reverse osmosis, distillation, activated carbon filtration, boiling, or ultraviolet (UV) light treatment. Test samples from each experimental group (n = 3/group) were cultivated on the appropriate media with colony-forming units (CFUs) reported.
Results:
All methods of bottle cleaning with tap water with/without detergent and microwave significantly reduced bacterial load (CFUs) by >99% (p < 0.05). Distillation and boiling of the contaminated water source eliminated 100% of bacteria, whereas reverse osmosis and activated carbon filtration did not. A single UV treatment of contaminated water within a bottle eliminated 99% of bacteria within the water and 100% in the bottle.
Conclusion:
Cleansing of NSI bottles with tap water with/without detergent or microwave produced robust bacterial disinfection. Distillation and boiling of a contaminated water source completely eliminated all bacteria. UV light treatment was capable of simultaneous disinfection of both the water source and bottle, suggesting this may be a convenient, 1-step method of preparing NSIs for patients.
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