BCIT ENVH Articles 2001-2013 | BCIT Institutional Repository

BCIT ENVH Articles 2001-2013

Air quality of indoor swimming pools
This research project examined the VOC levels in the atmosphere of an indoor pool. The main source of the VOCs within an indoor pool is from chlorination by-products such as chloramines and trihalomethanes. Trihalomethanes has been shown to be carcinogens and chloramines are irritants. There have been numerous reports of increased incidence of breathing problems in frequent swimmers as well as those occupationally exposed. Currently there are no limits established for VOCs within an indoor pool environment. This study involved using a direct reading instrument (VOC meter) to measure the levels of VOCs within a pool. The measurements took place over the course of a day on Dec 21, 2009 from the opening at 6 am to almost closing at 9 pm. The goal was to determine if the levels of VOCs changed over that period of time due to the build up of wastes within the pool, which would have increased voe production. The null and alternate hypotheses are as follows H0 : There is no difference in the VOC levels during the different times of day within an indoor swimming pool's atmosphere when measured by a handheld VOC meter. Ha: There is a difference in the VOC levels during the different times of day within an indoor swimming pool's atmosphere when measured by a handheld VOC meter. This hypothesis was tested via an ANOVA. Also, since numerous readings were taken anyway, readings were taken at different distances from the water surface in order to perform a regression analysis to see if there is a correlation between the distance from the water surface and VOC levels. It was determined that there was a significant difference in VOC levels during the different times of day within an indoor swimming pool's atmosphere when measured by a handheld VOC meter. However, there was no relationship found between the distance from the pool surface and the VOC levels., air quality, indoor air quality, VOC levels, indoor swimming pools, chlorination by products
Analyzing the tool of empowerment to improve the health of Vancouver's binning community
In the summer of 2007 a research project was conducted to analyze the socio-economic status and recycling habits of the dumpster diving community in Vancouver, British Columbia, Canada. This research, carried out by the City of Vancouver, was considered when amending the municipal Solid Waste By-law to permit the locking of dumpsters and to evaluate its impact on "binners" who rely on informal recycling for their livelihood. Due to the strain of changing municipal by-laws as well as many other issues "binners" have adapted by establishing partnerships with businesses to facilitate the activity of resource recovery. This project compared "binners" who have established partnerships with businesses (n=20) and those without (n=30) in order to examine each groups' perceived health. Dumpster divers were randomly surveyed at bottle depots using a face-to-face questionnaire and the results of this survey were interpreted with a chi square statistical analysis. The objective of this project was to examine business partnerships, as a tool of empowerment, and its relationship on the perceived health of Vancouver's "binning" community. There was no statistically significant association (p = 0.4) between the perceived health of "binners" who have established partnerships and those without. However due to a small sample population and limited resources a more in depth assessment must be carried out before conclusions can be made. The lead investigator's observations suggest that empowerment can be successfully used as a tool to improve the health of "binners." The health hazards that these individuals encounter daily are infinite but dumpster divers with partnerships have an increased potential to avoid dangerous exposures., environmental public health, dumpster diving, perceived health
BCIT Environmental Health Journal 2001-2013 Titles List
List of research projects completed 2001-2013. These projects are available for review in the BCIT ENVH Library. Please contact Helen Heacock or Bobby Sidhu for a specific paper., articles
Comparisons of the vehicular emission exposure levels of respirable particulate matter for three types of commuters
Previous studies implicate vehicular emissions as possible causes for asthma and asthmatic attacks in children, as well as elevated risks of adverse pregnancy outcomes, certain cancers, cardiovascular disease and even death. Due to the negative health effects associated with vehicular emissions particulate matter air pollutants were analyzed in an effort to establish which mode of transportation provides the least amount of vehicular emission exposure. The results determined the mode of transportation which has the least negative impact upon public health. The exposure levels of airborne particulate matter were examined between three types of commuters, those that traveled within the automobile environment by both car and bus and those that traveled in the outdoor environment by bicycle. Respirable particulate matter is an indicator species for both other harmful gases and ultra fine air particulates of vehicular emissions and therefore was chosen as the vehicular pollutant to be examined in the study. The DustTrak™ Aerosol Flow Monitor 8520 continuously sampled the exposure levels within the breathing zone of the researcher for the three modes of transportation during multiple, 3 hour, Wednesday evening rush hour intervals on the Stanley Park Causeway, in Vancouver B.C, during the month of January 2008. The results of the primary analysis of mean exposure levels were 0.0307, 0.0240 and 0.0175 mg/m3 for bus, bicycle and car respectively. The particulate matter exposure levels were then analyzed utilizing Kruskal-Wallis One-Way ANOVA, Scheffe's Multiple Comparison Test and Tukey-Kramer Multiple-Comparison Test which determined the probability level as less than 0.000000 and therefore the null hypothesis, there is no difference between exposure levels from vehicular emissions for commuters travelling by bus, car or bicycle, was rejected and a statistically significant difference between the three exposure levels was found. Although the particulate exposure levels were well below the maximum levels established by Health Canada, from the perspective of public health the car was the safest method of transportation with respect to particulate matter exposure levels., air quality, vehicular emissions, particulate matter, commuter exposure
Determining the relationship between drinking water quality of personal water bottles and cleaning practices followed by the public
It is becoming very common to see people carrying around personal water bottles throughout the day wherever they go, whether it be to school, work, or the gym (Rydings, 2004). People may have a false sense of security that the water they are drinking is safe because it is from the tap or from a commercial water bottle or cooler, but this may not be the case once you put it in a personal water bottle. Initially, there are guidelines in place to ensure safe drinking water from the tap and safe bottled water (Health Canada, 1996; CFIA, 2002), but there are no water quality guidelines once you put it in a water bottle. The purpose of this research project was to determine if a relationship exists between drinking water quality found in personal water bottles and the general cleaning practices followed by the public. The microbiological values obtained were compared to the Canadian Drinking Water Quality Guidelines to determine if they met the guidelines. Finally, it was assessed if public education was needed regarding cleaning practices for personal water bottles users. Both a short survey and microbiology testing were conducted. The survey was carried out by means of in-person interviews. Ninety participants were randomly selected by voluntarily responding to a posted sign requesting their participation. Approximately 110 ml sample of water from their personal water bottle was collected using a sterilized sample bag. Microbiological analysis was conducted within 30 hours of sample collection by means of Membrane Filtration and Heterotrophic Plate Count (HPC) using standard m-HPC agar. All microbiological and survey data collected was entered into NCSS in order to statistically analyze the results. The analysis of variance (ANOVA) was used to determine the differences between the types of cleaning methods (soap and water, rinsing with tap water and other methods) and microbiological counts. The results indicated that there was a significant difference between the types of cleaning. Tap water rinsing resulted in the lowest average microbiological counts and the post hoc test revealed that the greatest difference between the types of cleaning methods used were with soap and water. Correlational/Regression statistics were used to determine the relationship between the timeframe of cleaning and microbiological counts. The results indicated that as the timeframe between cleaning increases, so did the microbiological counts, however the relationship was weak. The microbiological counts found in this study, exceeded the Canadian Drinking Water Quality Guideline HPC maximum limit of 500 cfu/ml 74.4% of the time. Based on all the results of the study, government agencies or personal water bottle manufacturers should consider developing and disseminating to the public the importance of regular cleaning of personal water bottles and recommend the best methods to use., drinking water, personal water bottles, cleaning practices, Canadian drinking water quality guidelines, public education
The effect of ice resurfacing on carbon monoxide levels in indoor ice arenas
Once in awhile the news reports incidences of carbon monoxide poisoning in ice arenas. Nobody really thinks about whether or not the level of carbon monoxide will exceed to such a level that poisoning could occur in an ice arena. The purpose of this research study was first, to determine the carbon monoxide level before and after ice resurfacing and second, to check if the level, after ice resurfacing, was within the acceptable range. Thirty indoor ice rinks were chosen randomly from Greater Vancouver and the Fraser Valley. Two sets of samples were taken in each ice rink. The first set of samples was taken before ice resurfacing took place and the second set of samples was taken after ice resurfacing. Four readings were taken near the ice rink surface before and after ice resurfacing. A Q-Trak was used to measure carbon monoxide, temperature, and humidity. The statistical analysis was conducted by using the Number Crunching Statistical Software (NCSS). For the first part of the study, in which two sample sets were taken in each ice rink and the difference in levels were noted, a two-tailed t test was performed. The results obtained indicated that this study was statistically significant. For the second part of the study, a chi-square test was used to determine if the samples taken after ice resurfacing were within the acceptable range of carbon monoxide set by Health Canada and Ontario Recreation Facilities Association Inc. Two out of thirty ice arenas did exceed the acceptable range of 11 ppm set by Health Canada; however, all thirty ice arenas were within the acceptable range of 25ppm set by Ontario Recreational Facilities Association Inc. Attaching carbon monoxide sensors on walls and tuning the Zamboni regularly are recommended for ice arenas in order to reduce. the occurrence of carbon monoxide poisoning., air quality, carbon monoxide, indoor ice arenas
Electric hand dryers as a source of bacterial contamination
The most effective way to prevent disease is through hand washing, which includes the following four steps: using warm water, using soap and friction, rinsing and finally drying. Studies have shown that the ambient air within washrooms can contain bioaerosols which are released into the air through toilet spray, sneezing and coughing. Dryers have been found to be able to transmit these bacteria from the ambient air through to the exhaust air. If this were true, the electric hand driers could be a potential source for bacterial disease transmission. As a result the general public could be at risk of acquiring infectious diseases from electric hand dryers found within these washrooms. The purpose of this study was to demonstrate that the concentration of bacteria in the exhaust air of electric hand dryers was greater than that of the ambient air of the washroom. Sampling was done in 30 female washrooms selected randomly from the same facility. From each washroom 2 samples were taken, one from the hand dryer at the opening of the nozzle and one from the ambient air measured in the centre of the washroom. Samples were taken using settling plates for the dryer and a RCS for the ambient air, both containing nutrient agar. Bacterial counts for each sample were enumerated 48 hours after sampling. Results showed a decrease in bacterial counts in air from the hand dryers when compared to the ambient air. This significant difference (p < 0.05) suggests electric hand dryers are beneficial in reducing bacteria numbers found in the air. These electric hand dryers are capable of decreasing the bacterial concentrations found in the ambient air before passing over drying hands. Decreased bacterial concentrations in exhaust air of these dryers can lead to decreased bacterial recontamination of an individual's hands, potentially decreasing disease transmission rates., air quality, electric hand dryers, bioaerosols bacterial concentrations
Examining the impact of publishing restaurant inspection reports online
Purpose: The Vancouver Coastal Health (VCH) agency began putting restaurant inspection reports online in April of 2002. Sufficient time has passed to examine how effective the change has been on both Public Health Inspectors (PHIs) and restaurant operators in the region. Results of the research may influence how the online system is handled in the future. Methods: A survey addressing the impact of restaurant inspections online was either electronically mailed or done over the telephone/fax to PHIs in British Columbia, and to restaurant operators randomly chosen within the VCH region. Results: A total of 138 out of 411, or 34% respondents completed the survey from both groups. The two groups were found to have similar opinions with regards to online inspection reports with PHIs scoring slightly higher at 79% versus operators at 74%. Individual survey question scores on the whole were similar to what the total survey scores showed. Each survey question score from both groups were similar with operators scoring only four percent lower on average versus PHI scores. Correlation/regression analysis showed fair to good correlation with PHIs and Operator survey scores decreasing with increasing years in profession. Mean survey scores differed significantly between PHIs with online inspection reports in their health region (82.1%), versus regions without (76.7%). Conclusions: Survey results showed no difference of opinions between PHIs in BC and restaurant operators in the VCH region with respect to the impact of online inspection reports. Since both groups scored in the 74-79% range for the survey, one can suggest they feel there is a fair to major impact of online inspection reports on the public and their respective professions. From the survey question results, both groups felt the following if reports were online: They would slightly change their inspections/business operations. They somewhat agreed it enables the public to make informed dining choices. They would somewhat support an online reporting system if none was in their region. They somewhat agreed that other inspected public facilities should be posted online. It was somewhat important to post inspection reports online. PHIs definitely agreed the public had a right to see this information in this manner, whereas the operators somewhat agreed. A fair to good correlation was found for a decreasing survey score with increasing years of experience in their profession for both groups. Since age is usually tied with years in profession, this may indicate a greater reliance on the internet as a source of information for younger generations., food, online restaurant inspection report effectiveness, PHI and operator opinions
Public awareness of public health & environmental health officers in British Columbia, Canada
Environmental Health Officers (EHOs) are public servants who play a vital role in safeguarding the public health of Canadians. EHOs are both enforcers and consultants in public health. They inspect food premises, public facilities, waste disposal systems, residential houses, and recreational facilities to ensure compliance with government regulations. A survey determined level of knowledge with respect to public health in Canada and its EHOs. The survey included 458 participants selected randomly from White Pages for Vancouver, Burnaby and Surrey although only forty-two agreed to participate (response rate=9.1%). The study assessed associations between awareness of the role of EHO and gender, age, occupation, and level of education of respondents. The purpose of the survey was to increase the public awareness of the EHOs and to be a foundation study to create an effective public relations program in the province. Results failed to show any associations between awareness of the role of EHO and gender, age, occupation, and level of education of respondents. In conclusion, gender, age, occupation, and level of education are not major contributing factors in knowing the EHOs., environmental public health, environmental health officer roles, public awareness
Public awareness of the duties of environmental health officers in Canada
The purpose of the study was to examine the level of public awareness regarding Environmental Health Officers' (EHOs) roles and responsibilities in the public domain. EHOs as public servants are an integral component of the health care system and the recognition of their profession often goes unnoticed. In order to better serve the community, it is important for the public to know where to access resources and consult for help about health related issues. An electronic questionnaire, a service provided by Survey Monkey, was constructed and disseminated on January 12, 2013 via email using snowball sampling and posting on Facebook. There were a total of 161 completed responses by the closing date on February 10, 2013, and the data was statistically analyzed. For descriptive statistics, the participants had a mean score of 62.25% on their knowledge of EHOs' duties. The public was most aware that EHOs were involved in drinking water quality but least aware of EHOs involvement in land development. Conversely, the public was most aware that EHOs were not involved in social services but least aware that EHOs were not involved in lab testing. For inferential statistics, a one-way ANOVA was performed on each of the three demographic profiles - age, educational level, and field of study/work - in order to compare the mean scores of the different study groups within each profile. There were no statistical significant differences between public's knowledge on EHOs' duties and age groups, educational level, and field of study/work. This study suggested that public awareness regarding EHOs' involvement in various health service programs needs improvement. Awareness level was higher in health-related matters that have a perceivable direct effect on health and are often placed in the forefront of mass media. The study also indicated that EHOs do not receive enough recognition as educators or consultants of health-related issues. Further research is needed to assess strategies on increasing awareness and the issues identified should be studied with a larger sample population., environmental public health, environmental health officer duties, public awareness, health service programs
Sous vide chicken pasteurization temperatures
Sous vide is a cooking technique which involves vacuum-packaging raw foods and placing the packages into a water bath where cooking time and temperatures can be carefully controlled. One health concern regarding sous vide is the issue of cooking at below recommended temperatures; this practice can lead to the survival of foodborne pathogens such as Salmonella when dealing with chicken. Because sous vide utilizes non-conventional cooking temperatures, the margin for error is smaller and more care must be taken ensure food safety. Sous vide recipes vary greatly in terms of cooking time and temperatures, and as a result, there are a multitude of food safety concerns including the survival of pathogenic bacteria. This research project investigated one recipe which uses chicken breasts. The researcher logged the internal temperature of chicken breasts (n=30) as they were cooked according to a set recipe (66°C water bath for 23 minutes). The resulting values were then compared to time-temperature standards set by the Canadian Food Inspection Agency (CFIA) to produce a safe product. The experiment was conducted in conjunction with the executive chef at a Burnaby restaurant who is also a member of the British Columbia Centre for Disease Control (BCCDC) Sous Vide Working Group. A one-tailed one-sample t-test was used to determine the significance of the findings; the null hypothesis (H0 : measured temperature = target temperature) was rejected with a power of 1.00 at a p-value of 0.01. Chicken cooked under these particular sous vide conditions does not meet the guidelines for poultry set out by the CFIA. Undercooked poultry can cause foodborne illness and it is recommended that a longer cooking time or a higher temperature sous vide process be used. Alternatively, further heat treatment may be used to achieve the appropriate temperature and dwell times., food, sous vide chicken, pasteurization temperatures, time-temp standards
Survey of sanitation practices used on toys in general practitioners' waiting rooms in Vancouver, BC
Children are a highly susceptible group for many infectious diseases due to their underdeveloped immune systems. Environments with close contact to infected individuals and contaminated items pose a threat of communicability of invasive pathogens. Doctors' offices often supply toys in their waiting areas for children to play with. Many of the children entering a general practitioner's (GP's) office are already ill and their immune systems further compromised, leaving them at a higher risk of being infected. Due to the frequent oral contact with toys, they are most likely to be a fomite for infections. This study surveyed 30 general practitioners' offices in Vancouver, BC to assess the frequency and level of disinfection of toys in comparison to the reception countertops, another waiting room surface of equal hazard level. No association was found between the level of disinfection used and surface type cleaned (P=0.432993), however, an association was found between surface type and the frequency of disinfection used (P= 0.000036). The participants were also asked if they had a sanitation plan that includes the sanitation of toys (13.33%), and whether or not they provided soft toys (36.67%), as it has been found that soft toys are difficult to disinfect and are unsuitable for waiting rooms. Results of this study were then combined with a parallel microbiological assay to find no association between disinfection levels or frequencies and bacterial levels on toys. High aerobic colony counts were still found on toys in relation to countertops in the microbiological assay. Findings of this study suggest that although the disinfection frequency for toys is not associated with bacterial levels, it should still be increased, and a more stringent sanitation plan should be implemented and enforced in general practitioners' offices, as a safety measure to reduce the survival of other potential pathogens. Further research is required to assess the association between sanitation of toys in waiting rooms and the survival of other microbial agents., sanitation and disinfection, toy sanitation, microbial count, sanitation frequency, waiting rooms
Vehicle emissions containing ultrafine particulate
Background Ultrafine particulate is classified as particulate matter that is 0.1 micron in diameter and smaller. According to the BC Ministry of Health (2000), air-borne particulate matter generated by combustion is the dominant air pollution problem in British Columbia from a public health perspective. Vehicle exhaust is a major contributor of ultrafine particulate (UFP) in the atmosphere (Zhu, Hinds, Kim, Shen & Sioutas, 2005). Studies have linked high levels of ultrafine particulate matter to increases in emergency room visits, hospitalizations, and days lost from school and work (B.C. Ministry of Health, 2000). The purpose of the study was to examine the horizontal distance from Highway No. 1 where exposure to elevated concentrations of ultrafine particulate was likely due to vehicle emissions on this major roadway. Methods A portable P-TRAK manufactured by TSI was used to collect the data for this project as it provided real time data and was able to datalog (TSI, n.d). The P-Trak measures ultrafine particles by condensation counting technology in units of particles per cubic centimeter (cm3). The sampling was conducted in Burnaby at the Burnaby Lake Regional District Park. A background sample was collected at a greater distance from Highway #1 and compared to the subsequent samples that were collected at distances of 50, 100, and 250 meters in the park. Results Thirty samples were collected at each location for a total of 120 data points. The Analysis of Variance (ANOVA) indicated that the data was not normally distributed and that there was a significant difference of UFP concentrations at all of the locations. Correlation/regression determined that there was moderate relationship between UFP concentrations and distance from the highway and that with each meter traveled from the 50 meter start point next to the highway there was a 120 particles/cm3 decrease. Discussion The results of this study indicated that traffic on Highway No. 1 is responsible for elevated UFP concentrations in the vicinity of the Highway. Furthermore, it was determined that UFP concentrations exceeded background levels at an offset of at least 250 meters from the roadway. Finally, it was determined that UFP levels decreased as the distance from the freeway increased. These results indicate further research should be conducted to determine the influence of UFP concentrations on human health and establish an acceptable exposure limit. The findings of this study should be considered during planning for land use next to major roadways. For example, commercial/industrial buildings could be placed closest to roadways where public buildings that serve the most vulnerable including daycares and hospitals should be located at greater distances., air quality, vehicle emissions, ultrafine particulate, roadway proximity
Viewpoints towards the future public health technician position among the environmental health personnel
The purpose of this research project was to analyze and generalize the overall viewpoints of managers as well as PHI/EHOs towards the possible future creation of the new Public Health Technician position as well as to determine any impacts of this position on the PHI/EHOs. Due to the massive baby boomer retirements, there seems to be an apparent shortage of PHIs in the health authorities across Canada. Therefore, one of the ideas being considered in order to meet the future PHI demand is the creation of a Public Health Technician (PHT) position as a follow up to the idea suggested by Dr. Richard Musto, Executive Medical Director, Calgary Health Region. For the purposes of this project, the author invited PHI/EHOs as well as managers, directors and MHOs from various health authorities across Canada to complete a 3-5 minutes survey comprising of 14 questions via e-mail. The participants were given two weeks from February 6th to February 20th 2009 to complete the survey and send in their responses. The data collected was then analyzed using a Chi-Square Test with the help of the NCSS software at a significant level of α = 0.05. The Chi-square test determined that there is no association between the current status of employment of the public health personals and their belief that there is a shortage of PHIs in Canada (p-value = 0.43). The test also determined that there is no association between the current status of employment of the participants and whether or not they believed that the creation of the new PHT position would solve the problem of the perceived shortage of PHIs in Canada (p-value = 0.76). Overall, of the 77 public health personals who were surveyed, 61% believed that there is a shortage of PHIs in Canada. 91% of the participants had heard about the incoming of the PHT position and 65% believed that the creation of the technician position will not help solve this problem of shortage of PHIs in Canada. Most of them believed that increasing more awareness about the PHI profession would be a better alternative in dealing with the PHI shortage than creating a PHT position., environmental public health, public health technician, perceived PHI shortage
What's the "deal" on dented canned products
The following study was devised to determine whether dented cans should be sold in stores and if the refusal of dented cans from churches is a wise decision. The experimental procedures were set out to determine whether there is a significant difference in the proportions of contaminated cans to uncontaminated cans for two groups of dented cans and a group of non-dented cans. The pertaining legislation specifies to what extent a can should not be sold, however the extent of damage is usually at the discretion of an employee. Since the extent of damage could not be determined by the general public, this study looks at the type of damage. Two groups of dented cans were created to test if there is a difference in the likelihood of contamination between rim dents and body dents. A compression device was used to deliver a consistent force to each dented can. The forces at which the cans were subjected to were determined during a pilot study. The body and rim dented cans were subjected to 180 Newtons and 400 Newtons respectively. Two positive and two negative controls were made to test the microbiological component of this study. A total of 90 cans were tested for environmental organisms via the Pour Plate method. The results were statistically analyzed using the Chi-squared test. One out of 30 body dented cans showed the growth of microorganisms. In both the rim dented can group and the non-dented can group, no growth was found. The results of the study show that there is no association between dented and non-dented cans and the presence of environmental organisms as it reveals that the probability level of 0.363769 is greater than the set probability value of 0.05 and thus is not statistically significant., food safety, dented canned foods, environmental organisms, sterility, rim or body dent
Who is your child really spending time with at school?
Environmental surfaces, though they may appear clean, can harbour vast quantities of harmful pathogenic microorganisms. Therefore, it is imperative that proper cleaning and sanitation measures are in place to reduce the number of these microorganisms. This becomes even more important when those exposed to these environmental surfaces are a vulnerable group, such as elementary school children. To protect these children, surface sanitizers can be utilized to drastically reduce the amount of microorganisms present. One such sanitizer, SHC 50 General Sodium Hypochlorite Cleaner, was investigated to determine its effectiveness at reducing the microbial count on the desks of a grade on class. Twice a month the janitorial staff uses the sanitizer to clean the grade one desks. Within forty eight hours before and after the desks were cleaned, ten desks were swabbed and plated on 3M Aerobic Count Plate media and the resulting bacterial colonies enumerated. This was repeated for four separate cleaning periods. The final result was that the mean colony count of microbes on the school desks for the 'before' sampling period was 42 cfu/50cm2 , while for the 'after' sampling period it was 18 cfu/50cm2 . A chi squared analysis of the 'before'/'after' mean colony counts was used to evaluate whether the desks tested for before and after samples produced bacterial colony counts exceeding the recommended guidelines of 100cfu/50cm2. Of the eighty samples, only one 'before' cleaning sample exceeded the guidelines. The result was a p value of 0.314267 was obtained, resulting in the null hypothesis not being rejected and implying that there was no association between the mean aerobic plate count before and after sanitation of the desks. A one tailed independent samples t test was also performed, providing a p value of 0.0000 (99.9%). These result showed that there was a statistically significant difference in mean colony counts between the 'before' and 'after' cleaning periods. It could therefore be concluded that the SHC 50 General Sodium Hypochlorite cleaner was effective at statistically reducing the microbial load on the desks., sanitation and disinfection, environmental surfaces, elementary school children, microbial counts