Environmental Public Health Journal 2014 | BCIT Institutional Repository

Environmental Public Health Journal 2014

Pages

Air quality at bus stop microenvironments in a Metro Vancouver urban and suburban area
BACKGROUND Those commuters waiting in small-scale transportation microenvironments, such as bus stops, can be exposed to levels of pollution higher than what is registered by ambient air quality monitoring stations. In addition, historically, those commuting in urban areas experience greater exposure to air pollutants than those commuting in suburban or rural areas, due to the nature of the environment. Little quantitative research has been conducted in the Metro Vancouver area regarding air quality in small scale transportation microenvironments. OBJECTIVES The aim of this study was to assess the differences in commuter exposure during AM Peak and PM Peak periods between an urban (Vancouver) and suburban (Ladner) bus stop. Furthermore, results were to be compared to the Metro Vancouver 24 hour rolling average objective as well as nearby Lower Fraser Valley (LFV) Ambient Air Quality Monitoring Network stations. METHODS The author measured particulate matter (PM) 2.5 (particulate matter ≤ 2.5 μm in aerodynamic diameter), using the DustTrakTM Aerosol Monitor 8520 between January 6, 2014 and January 21, 2014 on 12 weekdays, from 6:30am to 7:00am and 5:00pm to 5:30pm, at Stop #55165 Northbound Harvest Dr at Ladner Trunk Rd in Ladner, BC and from Stop #50043 Burrard Stn Bay1 in Vancouver, BC. In addition, meteorological conditions, traffic density, bus volume, and other observations were taken during sampling periods. RESULTS The author found that average PM2.5 exposures were highest during the morning in Ladner (μ=34.38667μg/m3) and lowest during the morning in Vancouver (μ=13.44 μg/m3). In addition, there was a statistically significant difference (p<0.05) between Vancouver AM and the other groups (Ladner AM, Ladner PM [μ=28.07778 μg/m3], and Vancouver PM [μ=30.16667 μg/m3]), but the other groups were not significantly different from each other. Furthermore, the author found that the Vancouver AM average (μ=13.44 μg/m3) was below the Metro Vancouver 24 hour rolling average (25μg/m3) while all other groups (Ladner AM, Ladner PM, and Vancouver PM) exceeded this average. Lastly, when comparing all groups to the AM and PM hourly averages of their respective LFV Air Quality Monitoring Network stations (Ladner AM and PM vs. Tsawwassen AM and PM and Vancouver AM and PM vs. Kitsalano AM and PM), the author found that all groups averages exceeded the hourly averages of their respective stations. CONCLUSION Commuters’ peak hour exposures were significantly influenced by different microenvironments and were found to be higher than the ambient PM2.5 levels registered by the respective LFV Air Quality Monitoring Network stations. In order to address this, Metro Vancouver should implement personal exposure assessments, especially near roadways, to obtain actual levels of exposure to pollutants, such as PM2.5, by their residents. In this way, acute and chronic health outcome risks to air pollution can be better understood., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014, Published., Peer reviewed, air pollution, PM2, bus stop, commuting, microenvironment, personal exposure, ambient air, urban, suburban, Metro Vancouver
Are Ministry of Environment holding times for nitrate and nitrite tests in drinking water justified?
Background: Exposure to nitrate and nitrite in high concentration is associated with various health issues in humans such as methemoglobinemia, gastric and bladder cancers. Surface and ground water is vulnerable to nitrate and nitrite contamination which can have a significant impact to communities that use the water for consumption. Methods: Ion chromatography analysis of nitrate and nitrite degradation over time in well water from Abbotsford-Sumas Aquifer was performed in an analytical chemistry study. Nitrate and nitrite test strips marketed for testing drinking water were also used and results were compared to ion chromatography results. Results: Test strips used were unable to detect the level of nitrate/nitrite in the well water sample drawn from the Abbotsford-Sumas aquifer. Ion chromatography, IC, methods were able to detect measurable amounts of nitrates which resulted from concentrations of 1.17 mg/L NO3 as N to 1.13 mg/L NO3 as N from day 0 to 31 of the sampling date. The concentration decreased 0.04 mg/L NO3 as N over 31 days. Nitrites tested by IC were below the detection limit. Conclusion: In regards to nitrates, the MOE holding times are justified in that the concentrations were statistically different (p = 0.0001) from day 0 to day 31 from the sampling date indicating a change of concentration of the chemical due to time. However, the difference was not of a magnitude that may impact public health practices/policies. Test strips comparisons with EPA IC methods were non-conclusive since test strips were unable to detect measurable amounts of nitrate/nitrites. Future studies of nitrate concentrations with respect to chemical and biological components in water may lead to a greater understanding of its change in the environment and thus its association with other potential health hazards., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, holding times, gastric, bladder, test strips, Ion Chromatography, e.coli
Effects of light emissions from LCD monitors on public health
Background: Evidence suggests that exposure to prolonged use of computer monitors may lead to eye discomforts such as eyestrain, blurred vision, headaches, as well as computer vision syndrome. With the increase of internet and computer use at school and work, it raises a serious concern on whether or not the users are affected negatively. Objectives: The following study focuses on estimating the risk of using computers at the British Columbia Technology of Institute (BCIT) laboratories to determine if there is sufficient room lighting (illuminance) and monitor brightness (luminance) to ensure the safety of students at the school. Methods: Illuminance and luminance were both measured by means of a calibrated Unfors Xi light detector connected to a base unit. Several areas of each environment and monitor were measured and average values were taken to ensure that the data was reliable. The data were compared to applicable standards to determine if room lighting and computer brightness at BCIT were appropriate for safe student use. Results: The average illuminance was measured to be 405.4 Lux when the recommended level is 500 Lux. The results are considered statistically significant (p-value = 2x10-6). On the other hand, the luminance measurements averaged a reading of 94.6 cd/cm2 when the recommended minimum luminance level is 80 cd/cm2 (p-value = 0.99964). Discussion: The collected data show that the illuminance inside the BCIT laboratories where testing was conducted is not sufficient while the luminance of computer screens was found acceptable. Conclusion: The measurement of the illuminance inside BCIT laboratories showed that room lighting was insufficient and alternations of the monitor's brightness were made to compensate for insufficient lighting. It is recommended to increase room lighting in the tested laboratories in order to have all areas of the laboratory sufficiently lit at all times. This is to ensure that all students at BCIT are provided with a safe and healthy environment for computer use., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, LCD, illuminance, luminance, monitors, Unfors Xi, Light
The efficacy of alcohol-based hand sanitizers used in a series, modifying the ASTM E2755 method with a shorter hand sanitizer application time
Background: Alcohol-based hand sanitizers are becoming increasingly common in healthcare settings in an effort to control communicable bacteria, viruses and fungi of health significance. Much research has been done on the effectiveness of alcohol-based hand sanitizers but few studies look at the effectiveness when combined with more typical usage, such as varying application times and amounts. Methods: We looked at the efficacy of the microbial killing power of an alcohol-based hand sanitizer when used in a series of 5 applications. ASTM E2755 was used with the modification of a shorter application time (8 seconds from the recommended 30 seconds) of the sanitizer to better reflect actual healthcare worker usage. Results: We found an increase in the amount of indicator bacteria on the gloved hands of the subjects after repeated applications. However the increase was not significant enough in that a 2-log reduction of indicator bacteria was still achieved. Using a One Sample T-Test we found a very low probability value (<0.00000), indicating that the results were statistically significant. Conclusions: There is an increase of bacteria on gloved hands after repeated use of alcohol-based hand sanitizers. The results show a decrease in their effectiveness, most likely due to a build up of various non-alcohol components in hand sanitizers. However even with the 8 second application time there was still a greater than two log reduction even after 5 serial contaminations and applications. This cautiously shows that there is significantly less danger posed by more common shorter application times than originally thought. These findings have a potential impact on hand hygiene education as other factors, such as frequency or sanitizer amounts can be safely emphasized over application times., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, Alcohol hand sanitizer, Hand hygiene, ASTM E2755, Application time, Nosocomial infections
The efficacy of ATP removal on gym contact surfaces with disinfectant wipes.
Background: Gym equipment surfaces are known to harbor a range of contaminants due to the wide range of community use of the equipment. Certain gym equipment undergoes daily sanitation, however many other equipment surfaces do not. This study measures the levels of contamination on certain gym equipment surfaces at an educational institute gym facility and determines the contamination levels after disinfectant wipes are applied. Methods: The method to obtain the data was determined by the use of the Hygiena Systemsure II ATP analyzer in conjunction with Hygiena Ultrasnap ATP surface swabs. Gym equipment (barbells, dumbbells, machine handles, cable attachments) and other surfaces (benches, floor mats) were swabbed subsequently after a random gym patron had used the equipment to capture an accurate representation of the cleanliness of the surfaces. Disinfectant wipes were then applied to the same area before being swabbed again to determine contamination levels after disinfection. Results: The results demonstrated a statistically significant difference in the reduction of ATP levels with the use of disinfectant wipes with a p-value of 0.00001 at α=0.05. Alpha error was highly unlikely with a p-value being that low. Power was 99.9%, therefore there is a strong likelihood that we are correctly rejecting the null hypothesis. Conclusion: The study can conclude that disinfectant wipes do make a significant difference in surface cleanliness levels. Equipment that does not undergo routine cleaning such as the equipment used by the hands carry a much higher contamination rate than the body contact surfaces. Gym patrons should disinfect all body contact surfaces prior to use to reduce the risk of getting an infectious disease., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, Gym, Disinfection, Ultrasnap, Hygiene, ATP, RLU
Frozen foods and recommended packaging temperatures.
Background: Frozen foods have cooking instructions on their packaging, but due to foodborne illnesses resulting from consuming them, it brings the effectiveness of these instructions into question. The recommended cooking temperature on the packaging is a specific numerical value that is not open to interpretation and can be used to measure effectiveness. Methods: Temperatures were taken from 208 different meat products from different stores. The information recorded include: the store the products were found at, the type of meat, whether the product was uncooked or cooked, and if it had safe handling instructions. The data was compared to 3 different guidelines to see if they met the recommendations or not. The results of the comparison were then analyzed using Chi-squared tests. Results: A majority of T&T products failed in all 3 standards, the majority of products from Superstore passed using all 3 standards, and the majority of products from Costco failed using 2 standards. Conclusion: The amount of products that met recommendations is dependent on the store, the type of meat, the uncooked or cooked status, and the guidelines being used due to the recommended temperature of poultry being vastly different in one of the guidelines. The other products that did not meet recommendations were due to them being cooked products without a recommended reheating., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, Temperature, microwave, Regulations, Food Code, meat product, guidelines
How do you sleep at night?
Background: Sacrificing sleep on a daily basis has become a lifestyle for a growing number of people. This habit has been found to decrease overall cognitive health and performance. Raising awareness about benefits of a good night’s sleep and the negative effects of inadequate sleep is pertinent to shaping a healthy public conscience about sleep. It is also an important factor to consider for public health professionals since they must think critically throughout the working day and their work impacts those in their care. The purpose of this study was to assess the association between cognitive performance and sleep-related habits in a population of 31 Environmental Health students at BCIT during the Winter 2014 semester. Methods: A survey that collected subjective data on sleep-related habits and a brief cognitive test were used to assess cognitive performance. The cognitive test scores were marked with an index out of 20 and analyzed with a paired T-test to explore any differences from two study trials in January and February. Results: There was a significant decrease in cognitive index scores over the four week period. This was confirmed by a paired T-test with a p-value of 0.000005, with a significance level of α = 0.05. Average index scores were 18.91993 in January, 15.87063 in February, and the rounded average decline in scores was 3.13. Conclusion: Using an electronic device prior to going to sleep was deemed to be the most likely factor behind a significant decline in cognitive performance between January and February. Excessive exposure to light during naturally dark hours of the evening may curtail physiological processes during sleep (i.e. hormonal activities) effecting cognitive health and performance., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, Sleep, Cognition, Sleep deprivation, Mental health, Healthy sleep
Inspecting inspection reports, does the type of restaurant change the risk?
Background An estimated of 4 million Canadians (one in eight people) become ill every year from a food-borne illness (Thomas et al., 2013). The economic and social burdens of these illnesses are vast. As restaurants are a big sector of the food industry, improving their food safety would reduce the risk of food-borne illnesses. Environmental Health Officers (EHOs) are on the front line, educating restaurant operators in order to improve food safety. In Metro Vancouver there are many different types of ethnicities and types of restaurants; this provides a challenge for EHOs to know where to allocate their time and resources. Methods The author analyzed 150 Fraser Health inspection reports in the Burnaby, New Westminster and Surrey municipalities. The restaurants fell into three different categories: i) Independently owned ethnic, ii) Independently owned, non-ethnic and iii) chain non-ethnic restaurants. Hazard ratings, number of critical and number of non-critical violations from their latest inspection report were compared. Each violation code was also recorded to identify any infraction trends that exist. Results Analysis of the number of critical violations identified ethnic, chain non-ethnic, and independent non-ethnic restaurants as not being significantly different (p=0.09). The number of non-critical violations was different (0.033), with ethnic restaurants having the most. The number of critical violations, when treating each ethnicity as its own category, is however significantly different (p=0.044) between restaurant types. There was a significant association between hazard rating and restaurant type, with independent ethnic restaurants having the worst hazard rating (p=0.017). Conclusion The type of ownership (independent vs chain) and the restaurant type were not a factor when looking at number of critical violations that a restaurant commits. Independent ethnic restaurants had a slightly higher mean number of critical violations. Japanese restaurants had the highest number of critical violations out of the three ethnicities studied. These findings suggest a slight disparity in risk to public health between ethnic and non-ethnic restaurants., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed
Mechanically tenderized meat
Background: In 2012, mechanically tenderized meat raised public health concern when an E.Coli 0157:H7 outbreak was linked to the tenderization process. It was discovered that the machinery pushed the E.Coli from the surface of contaminated meat products such as steaks and roasts, into the interior, where it was able to survive the cooking process. Concerns were raised by Lorraine McIntyre and the BCCDC about this issue, and their desire to improve their knowledge base in order to adequately assess the risk. Methods: Data was gathered via a survey conducted electronically and by telephone. Questions were asked to determine the proportion of retail establishments that use their own tenderizing equipment. Questions also asked about other industry practices such as current sanitization and labeling practices. Results: The results of this study were that 24% of surveyed establishments mechanically tenderize their meat products. Of these establishments, 33% have a label that states the meat has been tenderized mechanically and 17% provide cooking instructions on this label. An association was found between mechanically tenderizing meat and establishment type, which suggests that grocery stores are more likely to mechanically tenderize than other establishments, such as restaurants. On the other hand, no association was found between operator experience and their level of knowledge regarding the risks of mechanical tenderization. Conclusions: Overall, this study has demonstrated the likelihood is high that consumers purchase and consume beef that has been mechanically tenderized at the retail level. The results from this study can be used to aid public health officials in quantifying the risk of mechanical tenderization at a retail level and aid in the development and implementation of new legislation such as mandatory labeling of all mechanically tenderized meat., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, mechanically tenderized meat (MTM), food safety, food retail establishment, survey, labeling
Non-celiac consumer knowledge regarding gluten-free diets
BACKGROUND: With the rising trend in gluten-free diets, it is imperative that there is high consumer product literacy so that the public makes informed decisions in regards to their diet and health. Knowledge taken from reputable sources and recognizing unsubstantiated health claims regarding gluten-free diets is critical for a non-celiac consumer. METHODS: A survey was used to investigate why non-celiac consumers elect to follow gluten-free diets and why they believe that the elimination of gluten from their diet is healthy. This project also tested consumer knowledge regarding gluten. RESULTS: During a 2 month period, total of 376 individuals participated in the survey. Only 322 participants fell under the inclusion criteria of this study. Women who elected to participate in gluten-free diets (but did not have Celiac’s Disease themselves) had higher overall test scores and men in the general population had lower overall test scores (p = 0.000017). CONCLUSIONS: Based on overall test scores and percentages of correct responses for specific questions, there seems to be deficiencies in both the average consumer and non-celiac-gluten-avoider-consumer knowledge regarding gluten, gluten-free products and diets., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, Survey, gluten, gluten-free, gluten-free diets, non-celiac gluten sensitivity
Safety and pH measurements of sushi rice in Japanese restaurants in Burnaby BC, Canada
Background and Purpose: The increasing popularity of sushi in Metro Vancouver raises public health concerns over the consumption of sushi rice being held out of temperature control. Although sushi rice is acidified to control growth of pathogenic microorganisms, there is no existing documented system to monitor the pH of sushi rice, and pH testing is rarely performed by Environmental Health Officers(EHOs)/Public Health Inspectors(PHIs) during routine inspections. The purpose of the study was to measure the pH of sushi rice samples collected from different sushi restaurants in Burnaby, BC and determine whether the pH meets the accepted standard of 4.6 or below. Methods: 30 sushi rice samples were collected from 30 randomly selected sushi restaurants in Burnaby, British Columbia. The samples were kept at room temperature and then tested for pH using the Waterproof Palm pH Meter. Results: The mean pH of the samples was 4.09; the median was 4.115; the standard deviation was 0.198; and the range was 0.82 with the minimum value of 3.71 and the maximum value of 4.53. 100% (30 out of 30 samples) had the pH less than 4.6. The statistical z-test resulted in a p-value of 0.00. Discussion: All of the sushi rice samples had pH values less than 4.6. Therefore, the samples were adequately acidified to inhibit the growth of pathogens. The low pH values indicate that the samples are not considered potentially hazardous food, thus safe to be stored at room temperature for extended periods of time. However, due to the nature of Bacillus cereus that can grow at a pH 4.3 or higher, the target pH of sushi rice is 4.3 or lower. Conclusion: Inadequately acidified sushi rice may pose a health risk if it is stored out of temperature control. The study shows that sushi rice being consumed by the public in Burnaby, BC is generally safe and has a low public health concern. Therefore, EHOs/PHIs can feel assured that sushi rice stored at room temperature is unlikely to cause potential foodborne illness., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, sushi, rice, pH, acidity, food safety, Bacillus cereus, Staphylococcus aureus, Burnaby, BC
Shelf-life study of a vegetable-based juice prepared using a masticating juicer
Background Home juicing has seen a rise in popularity because it gives people an appetizing way to get their daily intake of fresh fruits and vegetables. The roles of proper refrigeration, pasteurization, and acidification are all important in regards to determining the shelf life of a freshly made juice. As the general public may not properly understand these implications, this could become a major concern for public health officials. Methods A vegetable-based juice, made with carrots, celery, apples and parsley was made using a masticating juicer. Two versions of the juice were made, one original and one acidified. The pH, total coliforms, and total bacterial levels were monitored in both versions of the juice over a fifteen-day period. Results Analyses were carried out with the two juice samples. The pH values of the two juices were significantly different (p = 0.0000). No statistically significant difference was found in either the total number of aerobic bacteria or coliforms in the acidified and original juices. The relationship between total bacterial count and pH in the both the acidified and neutral juices were statistically significant, r= 0.7659, p= 0.0098 and r=0.7334, p=0.0158, respectively. No statistically significant correlation was found between coliforms and pH. Conclusion Although it was expected that the acidified juice would have had a lower levels of bacterial growth, this research project failed to show this. The total bacterial levels in the acidified juice was greater than 106 CFU/g on Day 8 and the original juice was greater than 106 CFU/g on Day 10. Regardless of the pH, the safest and lowest bacterial levels will be right when the juice is made., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2014., Peer-reviewed article, Published., Peer reviewed, home-juicing, pH, acidity, vegetables, food safety, farmers markets, bacteria, coliforms

Pages