Environmental Public Health Journal 2017 | BCIT Institutional Repository

Environmental Public Health Journal 2017

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Are absorbent pads suitable alternatives for tattoo dressing?
Background: Tattoo is a form of body modification that involves injecting ink underneath the epidermis using a needle. According to BC’s Guidelines for Personal Services Establishments this kind of invasive procedure will require wound dressing but the kind and sterility of the wound dressing has not been specified. During a tattoo convention an Environmental Health Officer (EHO) noticed that some tattoo artists were using absorbent pads for wound dressing. Absorbent pads are not sterile; therefore there is a concern of microbial infections at the tattoo wounds. This study examined the viability of using absorbent pads, which are non-sterile, as tattoo wound dressings. Method: 3M Quick Swabs were used to swab absorbent pads to collect the microorganisms present on the surface. 3M Petrifilm E. coli/Coliform Count Plates were used to culture E. coli and Coliform which could be present on the SanidermTM sterile tattoo dressing and absorbent pads. The presence of E. coli colonies on the petrifilm would show up as blue dots, while coliform colonies would be red dots. The total colony forming units (CFU), which include both E. coli and coliform colonies, were counted to assess the general sanitation conditions of both types of dressing. Results: Zero CFU were found from sampling the SanidermTM dressings and absorbent pads purchased from tattoo supply shops within Metro Vancouver. Conclusions: In the field of Environmental Health, coliform is often used as an indicator for the degree of sanitary quality; while E. coli is used as an indicator for fecal contamination. Therefore, the results of this study, indicated that the absorbent pads have high degree sanitation and are free from fecal contamination., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Absorbent pads, Meat pads, Tattoo, Dressing, Wound dressing, Sterile dressing
Assessing the risk of lead exposure to children from drinking water in Metro Vancouver child care facilities
Background: Environmental lead exposure has been a concern since the early 1970’s. With the reduction of airborne lead for inhalation, ingestion from food and water has become the major route of exposure leading to elevated blood lead levels. Previous research and the recent lead contamination of drinking water in Flint, Michigan demonstrate the vulnerability of young children and potential for exposure through drinking water. The purpose of this study was to assess and characterize the risk of lead contamination of drinking water for Metro Vancouver-area early childhood care facilities, and the effect of flushing fixtures as a control measure. Method: 91 drinking water samples were collected from various fixtures at 16 child care facilities at progressive time points to observe the effects of flushing and re-stagnation on total dissolved lead content. Analysis was performed using Varian AAS-240 coupled with GTA-120 graphite furnace atomic absorption spectroscopy. Results were analysed statistically using Excel 2010 and SAS/STAT® 14.2 software with SAS Studio 3.6 interface. Results: The mean (SD, min-max) lead concentrations of the water samples were 0.69 (2.32, 0.1-11.27) μg/L at zero minutes of flushing, 0.21 (0.44, 0.1-2.19) μg/L after one minute of flushing, 0.15 (0.17, 0.1- 0.87) μg/L after five minutes of flushing, 0.18 (0.17, 0.1 -0.64) μg/L after re-stagnation, and 0.31 (1.20, 0.1-11.27) μg/L overall. One outlier sample had a lead concentration of 11.27 μg/L, which exceeded Health Canada’s maximum allowable concentration of 10 μg/L. The decrease in mean lead concentration between zero minutes and one minute of flushing was statistically significant (p=0.0020). Conclusions: The results indicate that lead contamination of drinking water in child care facilities is present but below regulatory action levels under normal circumstances. The flushing of fixtures for at least one minute was shown to be effective in lowering lead concentrations further. Efforts should be taken to identify facilities at higher risk of lead contamination and to educate operators of flushing as an effective control measure., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Lead, Lead contamination, Drinking water, Children, Daycare, Lead leaching, Child care facility, British Columbia, Metro Vancouver, Burnaby, Fraser Health Authority
Association between knowledge of the pneumococcal vaccine, vaccination status and recommendations for vaccination
BACKGROUND Pneumococcal disease caused by Streptococcus pneumoniae has a high morbidity rate in elderly individuals aged 65 or older. Previous studies have demonstrated that low vaccination rates with the 23-valent pneumococcal polysaccharide vaccine (pneumovax) are due to a lack of awareness and knowledge about the vaccine in the general population. This study measured the association between the public’s knowledge of the pneumococcal vaccine, vaccination status, the type and number of health care facility visits per participant in the past year and number of advertisements seen for the vaccine. METHODS This study used a survey to test the knowledge of its participants on the pneumococcal vaccine and associated the results with nominal data such as vaccination status and recommendation for vaccination by their primary health care providers. The survey tested the participants using 15 true or false questions that assessed their knowledge on the pneumococcal vaccine and pneumococcal disease. RESULTS No association was found between the knowledge individuals have on the pneumococcal vaccine and whether their health care provider recommended the vaccine (p=0.467). However, a statistical difference in knowledge between individuals who are vaccinated and individuals who are not vaccinated was found (p=0.039 (CHI), p=0.011 (ANOVA)). There was also a positive association found between vaccination status and primary health care provider recommendation for the pneumococcal vaccine (p=0.001). No association was found between vaccination status and number of visits to a primary health care provider in the past year (p=0.149). Using an ANOVA analysis, it was found that there was a difference in number of advertising types seen for each vaccination status group (p=0.011). CONCLUSION Based on the results, it can be concluded that individuals who are vaccinated have more knowledge on the pneumococcal vaccine, but their knowledge is not affected by a recommendation to receive the vaccine from their primary health care provider. This suggests that health care providers are not providing sufficient information about the vaccine to their patients when they recommend it. Despite this knowledge gap, the association between vaccination status and primary health care provider recommendation for the vaccine indicates that individuals are more likely to get vaccinated when their primary health care provider recommends it. However, more visits to the provider annually did not influence the vaccination status of the patient. In addition, results from the ANOVA analysis suggest that participants who saw more vaccine advertisements were more likely to be vaccinated., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Streptococcus pneumoniae, Pneumococcal disease, Pneumovax, Vaccination, Knowledge, Advertisements, Health care provider recommendation
Determining the accuracy of colorimetric pH testing compared to potentiometric methods
Background: Bacterial growth in foods can be prevented by applying various controls to the food product, including adjusting the acidity of the food. Research has indicated that a pH level of 4.6 or lower will be effective to prevent most bacterial growth. In order to verify this level has been achieved pH test strips (colorimetric) or a digital calibrated pH meter (potentiometric) can be used. This study attempted to quantify the degree of accuracy that pH test strips have compared to the calibrated pH meter. Method: MColorpHastTM pH indicator strips with a pH range of 0-14 were tested against a calibrated Extech pH100 meter. In this study 40 samples of rice were acidified to varying levels. Each sample was measured with both colorimetric and potentiometric method. Results were compared to determine the level of accuracy of the pH test strips. As well, test strips were used to measure pH in a variety of different coloured preserves. Results: A two-tailed test showed that there was a statistically significant difference between the readings from the pH test strips and the digital pH meter (P=0.0003). Conclusion: Based on the results, it can be concluded that both methods of measurement are not equally accurate. A calibrated pH meter will give more accurate readings of pH levels and should be used in most cases to confirm food safety with a high degree of confidence. In testing dark coloured jellies and preserves, pH test strips should not be relied on as they will be stained by the food, making the colorimetric reading difficult to determine accurately., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, pH, Test strips, Calibrated pH meter, Food safety, Acidity, Accuracy, Colorimetric, Potentiometric, Comparison
DPD-based colorimetric quantification of free available chlorine (FAC) in floatation tank conditions
Background: Floatation tanks are quickly gaining traction as a form of relaxation, with numerous spas emerging in the Lower Mainland and beyond. The tanks are filled with a solution of magnesium sulphate, recycled between client uses. Thus, there exists a potential for microbiological contamination and subsequently, disease transmission. Health inspectors in BC may be involved the approval and inspection process for floatation tank spas; therefore, it is important to ensure that floatation tank environments are not a vehicle for disease. As a preventative measure, guidelines are in place for the halogenation of tank water at a level of 3-5 ppm free available chlorine (FAC). However, there is no standard method for the accurate and reliable quantification of FAC in high salinity environments. This study characterized the effect of high salinity on FAC readings from the HACH Pocket Colorimeter™, and derived a conversion factor to obtain an accurate reading for inspectors in the field. Methods: Floatation tank environments were simulated using USP-grade Epsom salts, Clorox™ bleach, and a hot water bath set at approximately 34°C (93°F). Assuming an initial concentration of 5.25% sodium hypochlorite, the bleach was serially diluted to obtain concentrations from 1-8 ppm. The final dilution step involved the addition of either 34°C water or an Epsom salt solution (MgSO4) at a specific density of 1.220 to create two solutions with identical amounts of bleach - one with and one without salt. The solutions were tested for chlorine two minutes later through the addition of DPD - a colorimetric dye that results with FAC - and measuring the colour intensity using the Pocket Colorimeter II. A percentage recovery was derived using the ratio between measured FAC with and without salt, Results: There was a statistically significant difference (p=0.05) between measured chlorine levels with and without salt as determined by a paired t-test. Further analysis via ANOVA and a post-hoc multiple comparison test (Scheffe's) indicated a dose-response relationship - increasing the amount of hypochlorite in an Epsom solution results in a statistically significant increase in measured FAC between the following groups: 1-2 ppm, 3-5 ppm, and 6-8 ppm of added hypochlorite. Linear regression revealed a strong correlation (0.97) between measured chlorine with and without salt. Conclusions: The HACH Pocket Colorimeter II™ can be used to estimate the amount of FAC in a floatation tank solution using a conversion factor of 0.79; to obtain an accurate measurement, divide the FAC reading in salt by 0.79, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Floatation tanks, DPD, Pocket Colorimeter II, HACH, Testing, Free available chlorine, Public health inspection, High salinity, Epsom salts
Electronic cigarettes
Background: Electronic cigarettes are a widely-used, yet still emerging technology. As such, there is relatively little data regarding the reasons why people take up their use. Many claim to use them as a smoking-cessation method. Concern exists that experimentation in non-smokers may lead to nicotine addiction and subsequent smoking. The purpose of this study was to determine the primary reasons for the commencement of electronic cigarette use, and to suggest way in which these findings could affect current policies and regulations pertaining to electronic cigarettes. Methods: A survey examining electronic cigarette use was prepared. The survey contained questions respecting primary motivation for use, frequency of use, present and former smoking status as well as agreement with common perception about electronic cigarettes. Basic demographic information was also collected. The survey was posted to “www.reddit.com” and was accessible to users who used electronic cigarettes themselves via the “/r/electronic_cigarettes” sub-Reddit for a period of five days. Once responses were collected, Chi-square tests of independence were run to determine if any associations existed. Responses were also compared to previous studies of a similar nature to see if any similarities existed. Results: In total, 155 responses were received. The majority of the respondents were males (89.7%) between the ages of 19 and 28 (47.7%). 30.32% listed their occupation as “student”, and almost three-quarters of the respondents had some post-secondary experience. 78.1% of respondents were former smokers, and 61.3% identified their primary reason for electronic cigarette use as “to quit smoking.” Chi-squared tests for association between responses yielded statistically-significant associations between being a previous smoker and believing that electronic-cigarettes are healthier than conventional cigarettes, and between gender (specifically being male) and reasons for electronic cigarette use (specifically “to quit smoking”). However, the latter result was possibly skewed by a higher response rate from males as opposed to females. Conclusion: The high proportion of previous smokers among electronic cigarette users suggested that quitting smoking was the most common reason individuals take up electronic cigarette usage. It is therefore suggested that studies be done to determine if their use is less harmful than that of conventional cigarettes, and that existing legislation regarding their use in public be modified in light of this evidence. It is also suggested that they be given consideration as a legitimate means of smoking cessation., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed
Environmental health officers and climate change adaptation in British Columbia
Background: The average annual temperatures in British Columbia have been steadily increasing in recent history and are expected to continue to rise. Climate change impacts have a significant effect on public health, and adaptation to these changes is necessary. Environmental health officers (EHOs) are in a position to deliver climate change adaptation programs in public health. The purpose of this study was to assess EHO perception of climate change adaption and identify knowledge or policy gaps. Methods: A self-administered online survey created used Google Forms was distributed through e-mail and social media to EHOs in BC. The survey asked for demographics information, beliefs about climate change, adaption, and public health. Chi-square tests and descriptive statistics were used to analyze results. Results: There was a significant association found between working in a mixed urban and rural environment and the incorporation of climate change adaptation into practice and the belief that climate change has impacted public health in BC. No association was found between years of experience and incorporation of adaptation. Conclusion: While EHOs generally recognize the public health impacts of climate change, there are many barriers preventing EHO involvement in climate change adaptation., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Climate change adaptation, Environmental health officers, EHOs, Public health
Evaluating the cleaning procedures of meat slicers at retail delis in Metro Vancouver
Background: Ready-to-eat deli meats are widely consumed by the public; however they are also a high risk food for carrying Listeria monocytogenes. Listeriosis, an infection that can result from consumption of Listeria monocytogenes contaminated food, is the leading cause of deaths related to foodborne illness in Canada. Due to structural constraints and inadequate cleaning, mechanical slicers used to process deli meats have been implicated as a major source of Listeria monocytogenes contamination of deli meats. Several governing bodies, including local health authorities have published recommendations on the proper method of cleaning and sanitizing meat slicers to prevent the risk of contamination of deli meats. This study evaluated the compliancy of retail delis in Metro Vancouver to these recommendations and also assessed their knowledge of the risk associated with deli meats. Methods: An in-person, self-administered paper survey was conducted at several retail delis and supermarkets. The survey questions determined the cleaning and sanitation procedures of meat slicers at the establishments and also assed knowledge of the risk associated with deli meats. Both nominal and numerical data was collected and analyzed using a Chi-squre test and a t-test. Results: Based on the data collected, a statistically significant difference was identified between the cleaning procedures practiced by the establishments and those recommended to prevent pathogen transmission through meat slicers. The chi-square test revealed that there is a statistically significant association between the size of the establishment and the adequacy of cleaning procedures, with small-scale delis being less likely to comply with the cleaning practices that are recommended by governing bodies. Conclusion: Cleaning procedures practiced at retail delis and supermarkets are not consistent with those recommended by regulatory agencies to prevent the transmission of pathogens such as Listeria monocytogenes from meat slicers to deli meats. Smaller retail delis are less likely to follow proper cleaning methods than larger supermarket delis. Educational intervention by health authorities may be needed to ensure that food establishments are informed of proper and timely cleaning procedures., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Deli, Meat slicers, Cleaning and sanitation, Listeria monocytogenes
Evaluation of public health interventions in shellfish tag compliance rates
Background: The recent Vibrio parahaemolyticus outbreak in the summer of 2015 highlighted that shellfish tags are one of the key pieces of information used to trace back and determine the source of a foodborne outbreak or illness associated with raw or uncooked shellfish. According to the Canadian Food Inspection Agency, all shellfish tags must meet the requirements stated in the Section 7.3 of the Canadian Shellfish Sanitation Program (CSSP). Non-compliant tags may hinder national and regional regulatory agencies from identifying problems in harvest locations and at the processors, and further impede provincial control measures. As a result of the national outbreak, the BC Center for Disease Control (BCCDC), Ministry of Agriculture and the Canadian Food Inspection Agency (CFIA), as well as health authorities and Environmental Health Officers (EHO) have been involved in a variety of actions and interventions to improve compliance. These include efforts to promote education and to improve control and surveillance of V. parahaemolyticus and other shellfish associated illnesses. This study examined the effectiveness of health agencies’ interventions to improve shellfish tag compliance rates to Section 7.3 of the CSSP by comparing the numbers of shellfish tags in compliance before and after the interventions that were implemented in 2016. Methods: 120 randomly selected shellfish tags were grouped into “Before” and “After” interventions. By assessing the date of processing, 60 tags collected before September 2016 were placed into the “Before” group. Another 60 tags collected after September 2016 were placed into the “After” group. Within each group, shellfish tags were individually analyzed to determine whether the tag met or exceeded the required quality, information, and type and quantity criteria. Shellfish tags were considered “Compliant” if they completely fulfill 10 components embodied in the criteria, whereas shellfish tags that failed to meet all the components were labeled “Non-compliant”. Results: Based on the statistical analysis conducted on the data, there was a greater proportion of compliant shellfish tags post-intervention compared to pre-intervention. The Pearson’s Chi-square test confirmed that there was a statically significant association (p-value = 0.000) between the numbers of shellfish tags in compliance and the interventions that were implemented after the outbreak. Conclusion: The results have demonstrated that the interventions implemented by numerous regulatory authorities resulted in greater compliance to Section 7.3 of the CSSP. Public health regulators including the Ministry of Agriculture and the CFIA, as well as BCCDC and EHOs should continuously be involved in a variety of actions, such as promoting education at the processor and retail level and also implementing interventions to improve compliance. By doing so, successful interventions and increased compliance rates will lead to rapid identification of shellfish-related illnesses or outbreaks and facilitate control measures that can expeditiously remediate public health issues., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Shellfish tag, Food traceability, Seafood traceability, Shellfish processing facility, Shellfish biotoxin, Food safety, Public health
Evaluation of the daycare mangers’ knowledge, attitude, and practice on lead in drinking water at daycares licensed by the Fraser Health Authority
Background: Daycares in BC fall under the Community Care and Assisted Living Act which require all daycare facilities to provide a safe environment, including drinking water. Young children who have been exposed to lead in drinking water at schools and daycares can incur serious health effects, including damage to cognitive development. Previous research has demonstrated that even low levels of blood lead concentration are associated with intellectual disability, slowed growth and development, lowered ability to concentrate, decreased academic achievement and behavioural problems. Individuals’ knowledge, attitude and practice (KAP) on drinking water can influence on how the children consume drinking water and potentially cause adverse health effects. This study evaluated daycare managers’ knowledge, attitude, and practice (KAP) on lead in drinking water related to this issue. Method: This study was conducted by collecting 106 responses from a KAP survey to evaluate the knowledge, attitude, and practices regarding drinking water contaminants. The survey was distributed to daycare managers in Fraser Health region. The responses were analyzed with regression and correlation, one-way ANOVA, and chi-square tests. Results: There was a statistically significant correlation between the age of daycare manger and their knowledge (t-test = 0.0309). All other tests showed no statistical correlation, difference, and/or association (p-value greater than significance level of 0.05 on all parameters) between managerial experiences, age of managers, types of daycares in their knowledge, attitude, and practice regarding lead in drinking water in daycare facilities. The data of KAP questionnaires indicated that most daycare mangers do not fully understand and not are sufficiently educated regarding lead toxicity in drinking water. Conclusions: The results of KAP surveys showed that an educational intervention by the government or local health authorities is highly recommended and needed to improve the daycare managers’ knowledge, attitude, and practice regarding lead in drinking water. Additional research is required to confirm this., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Lead, Water contaminants, Drinking water, Daycares, Knowledge, Attitude, Practice, Perception
Follow-up study of private well users affected by groundwater arsenic in the Surrey-Langley area
Background: Arsenic is a potent toxicant and Group 1 human carcinogen which occurs naturally in certain sediments and can contaminate groundwater. In the Surrey-Langley area of British Columbia, a 2007 study of private wells found that 43% of wells tested contained arsenic concentrations above the maximum acceptable concentration (MAC) prescribed in Health Canada’s Guidelines for Canadian Drinking Water Quality. The well owners who participated in the 2007 study were informed of the results and of effective treatment methods that would remove the arsenic contamination. This is a follow-up study that surveyed affected well users approximately 10 years later in order to identify whether the well users had subsequently made any water treatment or behavioral changes to improve the quality of their drinking water, and also to determine whether knowledge translation of the arsenic risk had been effective. Methodology: This study contacted and enrolled private well users who were living at properties which had previously been included in the 2007 study and, in 2007, were found to have arsenic levels above the MAC in the groundwater. Respondents who agreed to participate completed a questionnaire designed to identify what treatment methods or behavioral methods they use to mitigate the risk posed by arsenic contamination. Pre-treatment and post-treatment samples of their drinking water were collected and the arsenic concentrations were analyzed. The effectiveness of treatment devices for arsenic removal was evaluated. The groundwater arsenic concentrations from approximately 10 years apart were compared to identify if arsenic levels had changed. Results: Of the 42 properties that participated in the 2007 study and had groundwater arsenic levels above the MAC, 17 participated in this follow-up study. 14 of the participants also took part in the 2007 study 10 years ago. 79% of participants had not known prior to taking part in the 2007 study that their drinking water contained arsenic levels above the MAC. All 79% then either installed reverse osmosis treatment devices to remove arsenic from their drinking water, or switched to using bottled water for drinking. This indicates that knowledge translation of the health risk was effective. Of the 8 properties using treatment devices rather than bottled water, to mitigate the arsenic risk, 2/8 (25%) were ineffective at reducing arsenic. In addition, arsenic groundwater concentrations were not found to have changed significantly in 10 years (p = 0.11). Conclusion: Participation in the 2007 study was viewed as useful and informative by participants. Knowledge translation of the health risk and the need for risk mitigation was effective, but 25% of treatment devices were found to be ineffective at removing arsenic from drinking water. These results suggests that further knowledge translation of the need for routine testing for arsenic in post-treated drinking water may be beneficial to affected private well users., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Arsenic, Groundwater, Knowledge translation, Private well users, Surrey, Langley
Heterotrophic bacteria in botte refill stations
Background: Heterotrophic bacteria are commonly found in water supplies where there is inadequate or non-existent disinfection. Water coolers are known to have high HPC levels due to the filtered, non-chlorinated water provided. Water bottle refill stations utilize a carbon filter which can act as a food source for HPC. This study measured HPC levels in water samples from bottle refill stations to determine whether there is a difference compared to tap water at BCIT. Method: Standard Method 9060 A was used to collect water from bottle refill stations to compare to non-filtered tap water. Samples were plated using R2A Agar and incubated for 7 days before enumerating HPC from water samples. Samples were collected from specific drinking water fountains that contained Carbon Filters and compared to the nearest tap water source. Results: Mean HPC levels in bottle refill stations were found at 95 cfu/mL while mean HPC levels in tap water were 55 cfu/mL. A two-sample T-test confirmed that the mean HPC levels of bottle refill stations and tap water are statistically significantly different (P= 0.000124). Although the findings were statistically significant, the study’s power was low at 11%. Conclusion: Based on the results, drinking water obtained from bottle-refill stations at BCIT contained on an average higher level of HPC compared to tap water. Overall, HPC levels were below recommended levels in drinking water and not considered to have any harmful effects. To continue the safe use of bottle refill stations, facilities should develop and follow written procedures to maintain stations and ensure regular changing of filters., Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2017., Peer reviewed, Heterotrophic, HPC, Carbon filter, Drinking water

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