Safety Assessment: Benzalkonium Chloride as Sanitising Agent

Safety Assessment: Benzalkonium Chloride as Sanitising Agent Benzalkonium Chloride Benzalkonium chloride or BAC is an antibacterial agent belonging to the quaternary ammonium compound group. It is widely used in the health care industry and cosmetic industry as an antimicrobial and cleansing agent. According to the Food and Drug Administration (FDA), 0.1-0.13% w/w BAC is considered safe and effective as an â€Å"antiseptic drug product†.55 BAC has also been recognized as safe and effective when incorporated into oral mouth rinses.56 BAC is also popularly used as a rinse-free hand sanitizer and for hand washing.57 Short-term and long-term clinical studies have shown that BAC incorporated in intranasal products is safe and well-tolerated. 58 Furthemore, BAC meets the performance criteria under the Tentative Final Monograph for Health Care Antiseptic Drug Products as an active component in rinse-free hand sanitizers. Sufficient evidence exists to support the usage of BAC as a Category I active ingredient in 1994. It was analyzed as a leave-on sanitizer at the Final Monograph for Healthcare Personnel Antiseptic Drug Products. 59 A study by Dyer et al concluded that a hand sanitizer with BAC as the main component was a safe and effective way of decreasing illness absenteeism in grade schools.60 The safety of BAC was reviewed by an expert panel and they concluded that at concentrations of up to 0.1%, free active ingredient is â€Å"safe for human use†.61 It was acknowledged that BAC can be used beyond being an active ingredient for leave-on products because of its safety and antimicrobial effectiveness profiles. The FDA has also agreed upon the usefulness of biocidal quaternary amino actives, particularly BAC, in their previous rulemaking. As an example, the FDA stated that â€Å"it was not seriously concerned with the safety of ‘quats’ for first aid uses like wound cleansers, skin wound protectants, and skin antiseptics† in the 1991 Proposed Rule for Topical Antiseptic Drug Products for Over-the-Counter Human Use; Tentative Final Monograph for First Aid Antiseptic Drug Products. BAC was found to meet the requirements for first-aid antiseptic applications as reviewed by the expert panel at that time. Furthermore, the FDA has permitted the combination of BAC and Benzethonium Chloride homologues at concentrations of up to 0.004% as a food preservative or for long-term ingestible applications.62 At the 2002 16th Report of the Cosmetic Ingredients Review Expert Panel, BAC was announced to be safe at concentrations of up to 0.1% w/w. The cosmetic applications studied here were those that encompassed a daily-use regimen. A publication was done on a cross-over study of 420 grade-school children (5-12 years old) for a period of 10 weeks. They were told to use a leave-on sanitizer with BAC as soon as they entered the classroom, before eating their snacks and lunch, after sneezing or coughing inside the classroom, and after using the restroom. They observed that even with frequent use, there was no adverse reaction such as edema, rash or erythema, among the students during or after the study.40 Another study published in 1998 investigated the performance of an alcohol-free hand sanitizer with BAC. They concluded that the product exceeded the minimum performance standards indicated by the FDA for reducing bacteria.63 BAC has been reported to be effective against a wide variety of microorganisms, such as mixed-type viruses and non-enveloped viruses. BAC even demonstrated on some instances, a significantly higher virucidal activity as compared to alcohol applications. One important aspect of BAC that should not be over-looked is its non-flammable nature. In fact, during the SARS epidemic in 2003, BAC-containing sanitizers were very effective against human coronavirus especially in use in airlines and airports as alcohol-containing products were banned because of issues in flammability. In a study on BAC at reducing illness in public and private schools, they observed a 44.2% decrease in incidence of gastrointestinal illnesses and a 50.2% reduction in respiratory-related illnesses. In a different double-blinded study with 769 students, there was a 33% reduction in illness-related absenteeism. It was recommended that alcohol-free leave-on sanitizers, like those with BAC, are the only appropriate composition for usage in settings as school. This is due to the possible misuse of alcohol-containing sanitizers as a fire accelerant or by intentional ingestion. An excellent review on the issue of bacterial resistance to antibacterial  sanitizers was also recently submitted by SDA to FDA in response to the reopening of the docket for comments. However, the FDA advised that further studies should be done regarding antimicrobial resistance and the potential development of resistance to these agents, including BAC. This was stated at the joint meeting in 1997 of the FDA Advisory Committees. In the field of Orthodontics, Othman et al 64 confirmed that adding BAC to an adhesive produces antibacterial properties. In the study, BAC was incorporated into a light-cured composite resin, and an evaluation of its antimicrobial and physical properties was done. BAC was incorporated into Reliance Phase II adhesive to produce BAC concentration from 0.25% to 2.50% wt/wt. The modified samples were cut into disks and incubated in Strep. mutans for two days. Amount of bacterial inhibition was measured with agar disk diffusion assay. Other disks were placed in brain-heart infusion medium with Strep. sobrinus to measure its adherence. Cells that adhered were measured. Tensile bond strength was analyzed using a universal testing machine by attaching traction hooks to bovine teeth with the modified adhesives. Results showed an increase in antimicrobial activity in composites with higher BAC. Antimicrobial activity was negative for the composites without BAC. The composite with BAC and with out BAC did not show any difference with regard to their diametral tensile stress and tensile bond strength. Therefore, they concluded that when BAC was combined with an orthodontic adhesive, it added antimicrobial properties without changing its mechanical properties. Another study that aimed to create an antibacterial adhesive without compromising its bond strength was done by Saito et al.65 Their aim was to find the dose of BAC that exhibited antibacterial effect and did not compromise bond strength. In Saito’s study, Superbond CB resin cement was used. A mixture of the polymer, monomer, catalyst and BAC was produced according to the instructions of the manufacturer. Composite disks with the following BAC concentration were produced: 0.25%, 0.75%, 1.25%, 1.75%, 2.5%, and 5% (wt/wt). Composite disks of the same size (0.8 mm x 2 .0 mm thickness) were made. The test bacteria used were Strep. mutans 10449 and PS14, and Strep. sobrinus 6715 and B13. A brain-heart infusion medium was used to grow the bacteria. To evaluate the antibacterial activity, disk diffusion assay was utilized. To analyze the release of BAC as shown by an inhibition of growth of the bacteria, the semidiameter of the growth inhibition zone was measured. The bacteria were grown overnight in a broth and diluted. An optical density of 0.5 (550nm) was used. An inoculation of 80  µL (60-fold dilution) was performed on the brain-heart infusion agar plates. A glass rod was used to spread the inoculums evenly providing uniform bacterial growth. The BAC-infused composite disks were placed on the agar and were incubated at 37 ºC. Two days after incubation, the inhibition zones were measured. Saito also tested the shear bond strength using 70 extracted human premolars. The teeth were randomly distributed into seven groups and embedded in acrylic except for the buccal areas which were used for bonding. The teeth were polished using rubber prophylactic cups with pumic for 10 seconds. The teeth were etched with 65% phosphoric acid for 30 seconds and washed for 20 seconds then orthodontic metal brackets were bonded. Composite with the following BAC concentrations were used to bond the brackets: 0%, 0.25%, 0.75%, 1.25%, 2.5%, and 5%. A 300-gram force was applied on each bracket (based on the study of Bishara et al66). The results were presented in standard deviation and mean and analyzed with ANOVA to determine if there were significant differences among the groups. For multiple comparisons, Fisher test was used. Statistical differences were detected by a Chi-square test. Significance was predetermined at P 0.5.38 Results showed that there were significant differences among the composites with different BAC concentrations. No significant differences were found among the bacterial strains. When placed on the agar plate with Strep. mutans or Strep. sobrinus, no inhibition zone was observed on the composite with 0% BAC. The composite disks with BAC demonstrated a significant antibacterial property when compared with the composite without BAC. The antibacterial effect was found to increase as BAC concentration increased. This was indicated by an increase in the bacterial inhibition zones that were measured. The disks with 5% BAC had the highest amount of antibacterial activity. A significant difference in bond strength was noted among the different composites with BAC. However, as BAC concentration was raised, they observed a decline in shear bond strength. The study of Saito et al concluded that adding BAC into composite resin attributes antimicrobial properties strong enough to inhibit Streptococcus mutans and Streptococcus sobrinus. A clinically acceptable range of shear bond strength is yet to be established scientifically. Saito noted that incorporation of BAC does not lessen the strength to less than 10 MPa when an etchant (phosphoric acid) is used. The range of shear bond strength in study was 10.12 MPa – 20.94 MPa. Saito et al further concluded that a composite incorporated with BAC â€Å"has a possibility for clinical application as a bonding adhesive†. It was recommended in the study that it is essential to acquire a long-term release behaviour of an antibacterial agent. Therefore, a study investigating the release behaviour of BAC should be done. It was mentioned in the study by Saito that BAC has been a popular choice of contact lens antiseptic. However, the quantity of BAC used in the study was less than the amount used in contact lenses. A typical bonding procedure in an orthodontic patient requires around 150 mg of composite adhesive. Therefore, 0.7 mg of BAC is required to achieve 0.5% BAC concentration. The same author in 2009 evaluated the antibacterial activity and cytotoxicity of an orthodontic adhesive containing BAC. To achieve the desired concentration of BAC, it was initially diluted to 50% by mixing it with the orthodontic polymer (wt/wt). It was diluted further with polymer to achieve the required concentration. 65 They achieved the following BAC concentrations: 0.25%, 0.75%. 1.25%, 1.75%, 2.5%, and 5.0% (wt/wt). Custom-made molds were used to produce BAC-composite disks of the same size (8.0 mm x 2.0 mm). The disks were evaluated using antibacterial and cytotoxicity assays with three independent runs. To perform the disk diffusion assay, the BAC composite disks were soaked in distilled water at 37 ºC for 0, 30, 90, and 180 days prior to the assessment of antibacterial activity. The test bacteria used were Strep. mutans 10449 and PS14 and Strep. sobrinus 6751 and B13. They were routinely grown in a brain-heart infusion medium for 24 hours. The growth inhibition of Strep. mutans and / or Strep. sobrinus showed the release of BAC into the agar medium. Electric digital callipers were used to take measurements of the zone of growth inhibition around each BAC composite disk. To test the cytotoxicity, human gingival fibroblast cultures were grown from the cells of healthy gingival tissues from patients who were undergoing extraction prior to orthodontic treatment. This was copied from the method of Somerman, et al. After the patients underwent extraction, a part of the gingival tissue attached to the interdental papilla was taken. The samples were washed twice in phosphate-buffered saline solution (PBS). The acquired tissues were dissected into 1-mm cubes and were transferred to 35-mm tissue culture dishes with ÃŽ ±-minimal essential medium supplemented with 100  µg/mL of penicillin G, 500  µg/mL gentamicin sulphate, 0.3  µg/mL amphotericin B, and 10% fetal bovine serum. Incubation of the cultures was done in a 37 ºC humidified incubator with 95% air and 5% carbon dioxide. When confluence was reached, the cells were detached using 0.05% trypsin in PBS for 10 minutes. They were subcultured in flasks and seeded.38 The controls used in the study were the resin disks without BAC. The harvested gingival cells were laid under resin disks. In between the disks and the gingival cells was an 8  µm PET membrane that allowed the passage of the components of the resins to make contact with the human gingival cells. This was based on the study of Tang et al. Incubation with the gingival cells were done at 37 ºC for 1, 3, and 6 days.38 A reduction assay kit containing tetrazolium bromide was used to assess the cytotoxicity. This was based on the reduction that occurs to MTT when exposed to living cell mitochondria. It becomes purple fromazan. After 1, 3, and 6 days, the cells were cleaned with PBS after removal of the resins and the medium. Addition of 0.5 mL MTT medium solution was made to the wells. The solution was incubated at 37 ºC for 3 hours. A microplate reader was used to measure the purplish lysate. They observed significant differences among the different lengths of time the samples were soaked in distilled water and among the BAC concentration. With the different bacteria, they did not detect any significant differences. No difference that was significant enough was also observed between the bacterial strain and BAC. There were significant differences noted regarding the antibacterial activity at 0 day between samples with 5% BAC compared to other BAC concentrations. There were also significant differences observed regarding antibacterial activity among 0.25%, 0.75%, and 1.25% BAC, and 1.75%, 2.5%, and 5% BAC concentration. However, there was not any significant difference detected among 1.75%. 2.5%, and 5% BAC concentrations. There was a significant difference at 180 days between 0.25%, 0.75%, and between 1.25% and 5% concentrations. They observed that the higher the concentration of BAC in the composite, the greater the decrease that occurred in antibacterial property based on the assay time prolongation. They concluded that when the samples were not soaked in water, they exhibited higher antibacterial activity. The resins with 5% BAC had the highest antibacterial property. There was a significant decrease in antibacterial activity after soaking the samples in water for 180 days at all BAC concentrations. The samples incorporated with 5% BAC had the highest antibacterial activity compared to the resin with 0.25% at all periods of the experiment. In fact, the antibacterial activity exhibited by the resin with 5% BAC soaked for 180 days was the same as the antibacterial activity shown by the resin containing 0.25% and 1.75% BAC prior to immersion in water. There were significant differences in MTT activity percentages among the BAC composites with regard to cytotoxicity to the human gingival cells. Saito’s study concluded that resins with 1.25% or 1.75% BAC exhibited constant antibacterial properties when immersed in water for 180 days due to the continuous BAC release. However, an increase in cytotoxicity was noted as the antibacterial activity increased. Therefore, composites with a higher concentration of BAC were shown to be more cytotoxic. A concentration of BAC that was 0.25% or 0.75% exhibited cytotoxicity similar to the resins without BAC or the controls at all test periods. Saito et al recommended that a similar study be made using saliva instead of water as the immersing medium. This is due to the presumption that the oral environment is different that it may influence the antibacterial activity and cytotoxicity of the resins with BAC. The study confirmed that adding BAC to a composite resin exhibits an antibacterial effect against Strep. mutans and Strep. sobrinus. The author suggested that BAC be tested in vivo for safety before it is tested clinically.

Forgetting Sarah Marshall Essay

The movie â€Å"Forgetting Sarah Marshall† is a successful example of comedy. It was theoretical released on April 18, 2008. The film was brought together by a group of well acted performers and was very famous for perfectly combining the hilarious performances and the laughter together. I think that a successful comedy movie has to have these important factors. First, it needs to be performed with the perfect sounds elements such as the background music and the songs in the movie; second, the movie should be brought by some famous figures and directors, which were well-known in the comedy industry to make sure it will have a great hit this time; third, there should be a lot of stupid scenes with nonsense in the movie that will make people laugh their heads off. The movie â€Å"Forgetting Sarah Marshall† won the Golden Trailer Award for Wild Posts in the year 2008 and was nominated for 6 different awards such as the Golden Trailer Award Best Comedy, and Teen Choice Comedy Awards. The film is directed by the famous Nicholas Stoller and was written by Jason Segal. The movie was a successful hit and was well know among the teen’s group as well as the adults group. The main character of the movie; Peter, he had the most perfect life that all man wished for; which is dating the most famous and the sexiest TV star of the show Crime Scene, Scene of the Crime. But an awful break up which was brought up by now his ex-girl friend, TV star Sarah Marshall; Peter felt like he needs to get away from his life and forget everything about Sarah, so he decided to go to Hawaii for a vacation. The problem is Peter’s ex-girl friend is also on a trip to Hawaii with his new boyfriend; Snow. Peter had to learn to forget the past, stop being a baby, and finally become a man. In the movie, Peter is a sound effect editor for his ex-girlfriend’s TV show; Crime Scene, Scene of the Crime, he was suppose to do dark and ominous music for the background, after he broke up with Sarah, he was playing lively music for the show, which was a perfect part with sarcastic and dark humor in it. The movie cleverly blends together his act with his music talents. Such as the Dracula puppet song that he sang in front of a crowd of strangers that has no idea what he is doing, as soon as he is finished with the Dracula song; the awkward situation that everyone was in total silence was amusing and made the audience want to laugh without a reason. When Sarah Marshall’s new boy friend went on stage and sang her the song â€Å"Inside You†, with the ridicules body movements that he did with the song, the audiences are usually stunned at first, but as we watch it further, it definitely leads to full of laughter. A powerful comedy should be brought together by a group of well known figures in the comedy industry. â€Å"Forgetting Sarah Marshall† is a perfect example of a good comedy because it was produced by four producers, which they were all very famous for being in the comedy business for so long. The exclusive producer Richard Vane was also the producer of Last Holiday (2004), Rodney Rothman who was also the producer for Help Me Help You (2006), and Judd Apatow who was the actor in Pineapple Express (2008). Most importantly, Producer Shauna Robertson. She was the producer for many previous comedy great hits; such as the Pineapple Express (2008), Knocked Up (2007), The 40-Year-Old Virgin (2005) and Meet the Parents (2000). Jason Segal which was the writer of the film was also the leading actor of the movie. Actress Kristen Bell from the famous TV show Gossip Girl also took part in the movie, as well as Mila Kunis who was the sound for Meg Griffin for Family Guy and Bill Hader from Knocked up. With this impressive group of producers and performers, people will surge into the movie theater as soon as the film is released in the theaters. The most important element for a comedy is it has to have some scene that came out of nowhere and was totally stupid with nonsense. It is very important for a comedy, because people usually watch comedies when they don’t want to think about things and just want to enjoy the movie; otherwise there is no point of watching it. â€Å"Forgetting Sarah Marshall† is a perfect example because it is filled with nonsense. After breaking up with Sarah, Peter Felt like that he needs to have sex with different women just because his ex-girlfriend is having sex with another guy. After having a one night stand with a women that he barely even known, Peter cried in front of her and was acting totally out of ordinary. Also when the chief invite him to go and prepare dinner with him, they end up chasing a pig and Peter had to kill the pig with his bare hands. Scene in the movie shows much different nonsense that will usually make people laugh from their heart. The movie was loved widely all over the world, but there are still a lot of people who didn’t like the movie â€Å"Forgetting Sarah Marshall†. A lot of professionals’ movie critics didn’t like the movie because they think that the contents are â€Å"totally forgettable† or they think that â€Å"it is hard to like a character in the movie, when his own movie makes fun of himself. † I disagree with these critics, because there are many scenes in movie that people will not forget after that watched it, and a comedy are usually funny because the main characters were made fun of, either by himself or the other characters in the movie. That is what usually makes a movie a great hit of comedies. Just like what I previously mentioned, â€Å"forgetting Sarah Marshall† includes the perfect factors of sound element, was performed and brought together by a power group of people in the comedy industries, it also includes many stupid senses that people will not forget and will be talking about it among everyone who have watched the movie. This film is a great example of a comedy, and it is only for you to watch it and find out for yourself.

Communicating for Organizational Change - Free Essay Example

Sample details Pages: 2 Words: 653 Downloads: 8 Date added: 2019/10/10 Did you like this example? The mental health social work is a field of medical practice that is increasingly becoming important due to the rising stress levels within individuals and groups. Tackling the challenges in this field require innovation mainly through the use of technology in dealing some of the problems that patients, as well as the caregivers, face in the processes of treating the patients. The innovations are then communicated to the whole team of the caregivers ensuring a collaborative approach. Don’t waste time! Our writers will create an original "Communicating for Organizational Change" essay for you Create order This paper gives the importance of innovations and the use of leadership communication in providing some of the crucial services to the people with a mental health condition. In eth mental health social work, innovations are crucial in improving the quality of care that patients receive. In the medical practice, quality healthcare is at the core of service delivery. Innovations, therefore, ensure that better medication and equipment are used appropriately in solving the complex conditions that people with mental health problems face. Innovations further place the social workers and the whole team of caregivers into critical thinking mode in finding solutions for recurrent problems within the mental healthcare dynamics. The creative thinking approach can be initiated by good leadership who efficiently communicates the need for the innovations for both the patients and the caregivers (Gamble Gamble, 2013). Innovations are also important in improving the results of the caregiving process. The objective of mental health social work involves making the patients developing a sense of relief after starting medication. Those patients developing violent tendencies must be contained in a unique manner using modern equipment which does not necessarily involve anesthetics. All these results can only be achieved through a creative and innovative approach. Innovations ensure workflow planning involving the whole team yielding consistency, reliability and eventually success (Gamble Gamble, 2013). In the current mental, social work practice the most needed innovation is the collaborative approaches to health and technology. This innovation involves the integration of the caregivers and the patients in helping people who have mental conditions to lead the healthcare journeys through the use of digital information systems. The Collaborative on Health and Technology (CHaT) involves the collaborations of disruptive digital health provider options which are outcome driven. In the mental, social healthcare provision framework, the need to use digital technology in tackling the current issue is inevitable. Some of the healthcare problems include the rising cost and demand, the fragmentation of information and health records and the increasing need for patients to have more control over their healthcare as well as ways of engaging with the health professionals better. The future of medical practice significantly lies on the ability to harness the technological power in solving patients’ problems which require both vision and new working ways. CHaT precisely provides These requirements. The Collaborative on Healthcare and Technology is a disruptive outcome-driven model employing digital techniques in ensuring patient empowerment. The innovation is revolutionary since it is catalyzing the utilization of the digital care provision at scale for the result of patient empowerment. The team members responsible for the implementation of the CHaT have various features enabling them to pursue these goals. Some of the features include delivery of person-led healthcare through the use of technology, commitment to its development, the existing application within the healthcare practice, ability to go to scale and evidence of collaboration with the other team members. The proposed change cannot be realized unless mental health social worker employs effective communication plans to other team members. Implementing the change involves putting the team members through a self-reflection process which will pave the way for the change (Gamble Gamble, 2013). The leader must also emphasize the need for the change, outline some of the anticipated achievements and help the team members build on those accomplishments. The team leader according to Gamble Gamble (2013), must also institutionalize the progress from the change to make innovation a habit of the organization and a continuing process.

Who Invented LED or the Light Emitting Diode

An LED, which stands for light emitting diode, is a semiconductor diode that glows when a voltage is applied and they are used everywhere in your electronics, new types of lighting, and digital television monitors. How An LED Works Lets compare how the light emitting diode works versus the older incandescent lightbulb. The incandescent light bulb works by running electricity through a filament that is inside the glass bulb. The filament heats up and glows, and that creates the light, however, it also creates a lot of heat. The incandescent light bulb loses about 98% of its energy producing heat making it quite inefficient. LEDs are part of a new family of lighting technologies called solid-state lighting and in a well-designed product; LEDs are basically cool to the touch. Instead of one lightbulb, in an LED lamp there will be a multiple of small light emitting diodes. LEDs are based on the effect of electroluminescence, that certain materials emit light when electricity is applied. LEDs have no filament that heats up, instead, they are illuminated by the movement of electrons in a semiconductor material, usually aluminum-gallium-arsenide (AlGaAs). The light emits from the p-n junction of the diode. Exactly how an LED works is a very complex subject, here is an excellent tutorial that explains this process in detail: Background Electroluminescence, the natural phenomena upon which LED technology is built was discovered in 1907 by British radio researcher and assistant to Guglielmo Marconi, Henry Joseph Round, while experimenting with silicon carbide and a cats whisker. During the 1920s, Russian radio researcher Oleg Vladimirovich Losev was studying the phenomena of electroluminescence in the diodes used in radio sets. In 1927, he published a paper called Luminous carborundum [silicon carbide] detector and detection with crystals about his research, and while no practical LED was created at that time based on his work, his research did influence future inventors. Years later in 1961, Robert Biard and Gary Pittman invented and patented an infrared LED for Texas Instruments. This was the first LED, however, being infrared it was beyond the visible light spectrum. Humans can not see infrared light. Ironically, Baird and Pittman only accidentally invented a light emitting diode while the pair were actually attempting to invent a laser diode. Visible LEDs In 1962, Nick Holonyack, a consulting engineer for General Electric Company, invented the first visible light LED. It was a red LED and Holonyack had used gallium arsenide phosphide as a substrate for the diode. Holonyack has earned the honor of being called the Father of the light emitting diode for his contribution to the technology. He also holds 41 patents and his other inventions include the laser diode and the first light dimmer. In 1972, electrical engineer, M George Craford invented the first yellow colored LED for the Monsanto Company using gallium arsenide phosphide in the diode. Craford also invented a red LED that was 10 times brighter than Holonyacks. It should be noted that the Monsanto Company was the first to mass-produce visible LEDs. In 1968, Monsanto produced red LEDs used as indicators. But it was not until the 1970s that LEDs became popular when Fairchild Optoelectronics began producing low-cost LED devices (less than five cents each) for manufacturers. In 1976, Thomas P. Pearsall invented a high-efficiency and extremely bright LED for use in fiber optics and fiber telecommunications. Pearsall invented new semiconductor materials optimized for optical fiber transmission wavelengths. In 1994, Shuji Nakamura invented the first blue LED using gallium nitride.