Environmental Public Health Journal 2016 | BCIT Institutional Repository

Environmental Public Health Journal 2016

Blood concentrations of lead and mercury in British Columbians (2009-2010)
Background and Purpose: Adverse effects of lead and mercury on human health due to environmental and occupational exposures require a public health attention. These metals can cause severe harm to vulnerable populations such as children and pregnant women. The probability of chronic and harmful exposure is higher in occupational settings. Monitoring the levels of these two metals in blood is an important tool to identify and quantify exposure to these metals in the environment. Monitoring data provides vital information required for management of health risk posed by these metals. The purpose of this study was to perform a comparative analysis of blood lead levels and blood mercury levels within the province of British Columbia on the health services data obtained from BC Centre of Disease Control. The primary objective was to compare the levels of lead and mercury in blood among different health authorities of British Columbia. The secondary objective was to compare the levels of lead and mercury among different age groups and gender. Methods: The blood lead and mercury concentrations used for the analysis were provided by Environmental Health Services at the British Columbia Centre for Disease Control (BCCDC). The data comprised of blood analyses that were ordered by physicians during the period of 2009-2010 for reasons not disclosed. Access to this data was provided by Dr. Reza Afshari with the permission of Dr. Tom Kosastsky for the completion of this project only. Statistical analysis of data was performed using Microsoft Excel 2013 and SAS University Edition Analytic Software. Various descriptive and inferential statistical tests were performed on the data to determine the differences of blood mercury and lead levels among different genders, Health Authorities and age groups. Results: The levels of blood mercury and lead concentrations were not significantly different in males and females in province (p-value 0.5543 for mercury; p-value 0.5336 lead). However, it was found that blood levels of lead were higher in Interior Health and “Unknown” category (p<0.02), while blood mercury levels were significantly higher in coastal health authorities (highest in Vancouver Coastal Health Authority, followed by Fraser Health Authority and Vancouver Island Health Authority) (p<0.001). For both toxic metals, levels were highest in age group of 50 and above. (p<0.0001 for mercury, p<0.02 for lead). Conclusion: The statistical analysis of lead and mercury data was useful in characterizing the exposure among Health Authorities, age and sex of the people tested in province of British Columbia. Analysis of mercury data has generated clear patterns inferring association between coastal Health Authorities and elevated mercury levels. Vancouver Coastal Health had highest median mercury levels 4.02 μg/L higher than other health authorities (p<0.0001). Analysis of lead data established a pattern among physicians suggesting that they are more likely to order a test if the patient is under 18 years of age. Median levels were found to be highest in Interior Health Authority and “Unknown”, 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, 2016., Peer reviewed, Lead, Mercury, Pregnancy, Children, British Columbia, Blood lead levels, Blood mercury levels, Vancouver Coastal Health, Fraser Health, Interior Health, Northern Health, Vancouver Island Health Authority, Occupational exposure
The effect of seafood consumption on the memory of post-secondary students in B.C.
Background and Purpose: Seafood makes up a significant portion of the diets of people around the world. Especially fatty fish such as salmon and herring, seafood items contain numerous nutritional benefits including omega-3 fatty acids which studies have shown aid in cognition and memory. However, due to natural and anthropogenic sources of pollution, contaminants such as mercury which studies suggest decreases cognitive functioning if consumed in excess bioaccumulate in marine life including various fish and shellfish species. The purpose of this study was to categorize participants into either the “fish” group (more fish than shellfish consumed) or the “same” group (either more shellfish than fish consumed or equal amounts of fish and shellfish consumed) via a seafood frequency questionnaire, and to administer a memory test to the participants to determine whether there is a significant difference in mean memory test scores between the groups. Methods: 31 participants were randomly selected at BCIT to participate in the study. Participation was voluntary and participants were given written and oral instructions on how to complete both the seafood frequency questionnaire and memory test. Memory test scores were based on the length of the longest digit sequence that the participant was able to recite upon hearing the examiner list the sequence. The highest possible score was a 10, while the lowest possible score was a 1. Results: The mean memory test scores of the groups, “fish” (more fish than shellfish consumed) and “same” (either more shellfish than fish consumed or equal amounts of fish and shellfish consumed), were 5.83 and 5.92, respectively. The median memory test scores of the groups, “fish” and ”same”, were both equal to 6. The standard deviations of the groups, “fish” and “same”, were 1.2004901 and 0.9540736, respectively. The ranges of the groups, “fish” and “same”, were 4 (minimum) to 8 (maximum) and 5 (minimum) to 8 (maximum). From the non-parametric Wilcoxon Rank sum test, the P-value was found to be >0.05 at α = 0.05. Conclusion: The results of this study suggest that diets relatively high in fish are neither positively nor negatively correlated with memory. However, the limitations of this study in combination with the various studies that contradict this study’s findings illustrate the need for further research., 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, 2016., Peer reviewed, Memory, Seafood, Shellfish, Fish, PCBs, Mercury, Brain, Neurodevelopment, DHA, EPA, Omega-3 fatty acids
Evaluation of the public’s knowledge, attitude, and practice on seafood contaminants
Background: The public perceives seafood generally as a healthy food. Studies have shown that consumption of fish is associated with healthy heart function. However, the benefits of consuming seafood may also come with some risks, which may not be well-known by the public. Seafood can potentially contain contaminants that originate from the natural environment or pollutants from human activity. The contaminants of interest that were focused on in this study include lead, mercury, organophosphates, and domoic acid. Methods: The study utilized a KAP (Knowledge, Attitude, and Practice) survey to evaluate the knowledge, attitude, and practices regarding these contaminants between the general public and those working in the seafood industry. Nominal data was analyzed by the chi-square test while numerical data was analyzed by the t-test. Results: The data obtained did not show a statistically significant difference between the general public and the seafood industry (p-values greater than significance level of 0.05 on all parameters) in their knowledge, attitude, and practice regarding seafood contaminants. Conclusion: There was no difference between the general public and the seafood industry in their knowledge, attitude, and practice regarding seafood contaminants. Although the attitude data was not significant, the effects of some chemical contaminants (organophosphates and domoic acid) were generally incorrectly perceived by both groups unlike biological contaminants. Additional research will be required, but results from this study show that educational intervention by the government or health authorities may be needed., 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, Organophosphates, Seafood, Contaminants, Knowledge, Attitude, Practice, Perception, Domoic acid, Lead, Mercury