to certain metals. Based on the permissible exposure limit (PEL), it is 0.2ppm. In accordance with OSHA’s PEL, glutaraldehyde prod-ucts should not be sprayed. Phenol Phenol-based products are regis-tered as disinfectants and are the most commonly used. Required contact times are typically 10 minutes, although some phenol-based products have ONE-minute effi-cacy claims against HIV. Be aware that other microorganisms still require 10 minutes. According to the EPA (epa.gov/ttnuatwl.hlthet/phenol.html ), phenol is “flammable, corrosive, and very toxic,” and “ingestion of even small amounts may cause vomiting, circulatory collapse, paraly-sis, convulsions, and coma.” Pheno-lics are commonly known to cause sinus and respiratory problems as well as headaches due to overexposure. Always use phenols in a well-venti-lated area. Typically, phenols are a two-step process, first remove the gross filth, and then reapply to the specified contact kill time to the remaining pathogens. product is placed in the hands of the person mixing and measuring the product. The bleach mixture’s effectiveness breaks down quickly once mixed and should be stored away from light to remain effective. Bleach mixtures have a shelf life of no longer than 48 hours. handling and diluting of this product make this an outdated form of disinfecting. Quaternary Ammonium Chlorides Quaternary ammonium chlo-ride products are registered by the EPA as disinfectants. There are numerous kinds and combina-tions of quats; all are known for having low toxicity and depend-ing on the formula relatively fast contact times against a wide range of organisms. Generally, disinfectants that contain quats require a 10-minute contact time for most organisms, except HIV, which is typically one minute or less. Quat evolution is now in its fifth generation, which began in the 1930s. Sodium Bromide and Sodium Dichloroisocynurate Dihydrate Sodium bromide and sodium dichloroisocyanurate dihydrate (NaDCID) act on the same principle as bleach. They oxidize organic matter. When NaDCID is added to water, chloride is produced. Unless the water is free of organic material, the chloride then forms hypochlor-ous and hydrochloric acid. The acids are the ingredients that actually kill the microorganisms. A small amount of sodium hydroxide (lye) is also formed when either bleach or NaDCID is used. Sodium bromide reacts similarly and when added to water hypobromous acid is formed. Currently, only one product is regis-tered with this ingredient combina-tion. As with bleach, mixing is required and the issues of odor and instability arise. The effectiveness of this product is in the hands of the person mixing the product, espe-cially the right amount of water per pellet is crucial. This product needs to be kept away from heat, mois-ture, and sunlight. New Generation Quat / Alcohol Technology Combining the new fifth genera-tion quats with alcohol (either isopropanol or ethanol) resulted in even lower contact times (LESS time required to kill the target microbes). Faster kill times enable a surface to be disinfected quickly. Due to the presence of alcohol (which evapo-rates quickly and leaves little, if any, residue) it reduces the fear of cross-contamination. There are two types of quat/alcohol products, those with less than 40% alcohol and those with more than 40% alcohol. Faster kill times are obtained with the higher concentrate alcohol products. An excessive amount of quat (greater than 0.3%) causes staining and does not increase prod-Sodium Hypochlorite (Bleach) Bleach is a well-known antimi-crobial and is effective under certain conditions. To be sold as an antimicrobial it must be EPA-regis-tered. Because bleach reacts with (oxidizes) organic material such as blood, tissue, saliva, or microbes, the more organic material present, the more it has to oxidize. As a result, the ratio of organic material may be too high relative to the amount of bleach available. In other words, the amount of bleach in the mix may not be efficient enough to kill the targeted microor-ganisms. Due to the bleach’s reac-tivity potential it is corrosive and should not be used on certain metals. Odor is also an issue. Some manufacturers have used masking agents but the strong chloride smell is still apparent. While bleach’s kill times are better than average, its odor and chemical instability are major drawbacks. Bleaches that are mixed may create potential prob-lems in that the effectiveness of the Iodophores Iodophores are registered as disinfectants. They are widely known to discolor surfaces, though newer formulations are less so. Iodophores have a relatively slow kill time (10 minutes and up), and most impor-tantly, the dilu-tions and contact times are critical for efficacy. They must be discarded and remixed daily and may be inacti-vated by hard water. Staining, slow kill times, and the required www.orthodontics.com May/June 2012 17
Journal of the American Orthodontic Society May-June 2012: Page 17
