| Full Text | 1.1 Background
Because of the 2001 Mercury Agreement, the CBHSSJB reconstituted its Mercury Program in the context of a more comprehensive environment-and-health program. One of the goals of the CBHSSJB was to set up long- term monitoring and surveillance activities focusing on mercury and other contaminants in the Eeyou communities. Around this same time, concerns about the health impact of mines tailings in Oujé-Bougoumou led to a study of people’s exposure to contaminants there and in a control community, Nemaska. Following this, a feasibility study regarding the possibility of a broad environment-and-health study was conducted in the other Cree communities during the period November 2003 to the end of March 2004 and provided valuable feedback. Subsequently, an environment-and-health study, referred to as Nituuchischaayihtitaau Aschii, was proposed for funding through the Mercury Agreement. Its rationale was mainly based on the issues raised during the two previous studies, but also on the basis of known research gaps. It was to take place over a five- year period of field work, with the 2005 assessment in Mistissini constituting its pilot phase. The field work for the communities of Eastmain and Wemindji was completed during the summer of 2007.
1.2 Report outline
This current report consists of eleven chapters that provide the following information: abbreviations and glossary of Cree terms (Chapter 2); project background, objectives and scope (Chapter 3); field study methods (Chapter 4); results and discussion (Chapter 5); seroprevalence of zoonoses (Chapter 6); microbial contamination of natural water sources (Chapter 7); educational activities (Chapter 8); reporting of results (Chapter 9); project evaluation (Chapter 10); study findings and key messages (Chapter 11); and the references quoted. Supporting documentation is provided in 7 Appendices.
1.3 Study populations
The communities of Wemindji and Eastmain were successively visited during the summer of 2007. Sampling of the population followed a stratified design, considering the following age categories: children between 0 and 7 years old, children between 8 and 14 years old, teenagers and adults between 15 and 39 years old, and adults over 40 years old. The selection of participants within each age stratum was done using simple random sampling, without replacement.
1.4 Dietary habits
Traditional food is enjoyed more frequently by adults over 40 years of age than younger individuals. They eat more game, fish, birds, and berries than younger adults or children. These foods are an excellent source of good (healthy) fats, proteins, iron, and zinc. However, the study showed that in general, people in Eastmain and Wemindji eat too much unhealthy fat (including trans fats from store-bought baked goods). Blood levels of a good type of fat (omega-3 fatty acids) reflect the consumption of wild animals (fish and game), and increased with age, which is consistent with the higher consumption of traditional food observed in older age groups. On the other hand, unwanted industrial trans fats (in fries, industrially prepared and packaged foods, etc.) showed the opposite trend, with higher levels found in the younger age groups. Also, a high proportion of children (more than 50%) reported consuming sweet drinks, with an average of 2.2 cans per day in Wemindji and 1.3 cans per day in Eastmain accounting for more than 10% of energy intake. The fact that teenagers have higher levels of trans fats in their bodies and a high intake of sugar suggests that they are at increased risk of developing heart diseases and diabetes in the future. Finally, the average daily consumption of fibre and vegetables is low, which could increase the risk of chronic diseases such as diabetes and cancer of the bowel. Also, since fruit and vegetable consumption is low, some vitamin and mineral intakes are too low based on the diet of study participants.
Despite the fact that healthy traditional food is still part of the diet (especially in older age groups), a transition toward a more unhealthy diet high in sugar, saturated fat and trans fat is observed, especially in young people; this could have negative health impacts in the future.
1.5 Physical activity
Physical activity was assessed using a questionnaire. Unfortunately, we did not have enough participants to show trends for this in Wemindji and Eastmain. However, in Mistissini, the results suggest that the dedicated walkers are enjoying the health benefits of their physical activity and that physical activity in general can improve health status in Eeyouch.
1.6 Environmental contaminants
The environment is contaminated with different chemicals originating from human activities. Some of these contaminants called “persistent organic pollutants” (POPs) accumulate in fatty tissues of animals and humans, are difficult to break down, and are transported long distances by water and air. Consequently, they are found in environments where they were not initially released, such as in the North. Examples of POPs are PCBs, organochlorine pesticides (a class of pesticides formerly used but now banned since the late 70s-80s), some industrial by-products/waste such as dioxins, and other types of domestic or industrial chemicals such as water and stain repellents or fire retardants that tend to leach out of plastics and textiles or from electronic devices. The environment is also contaminated with toxic metals which tend to accumulate in the liver and kidneys as well as in the flesh of animals and humans, rather than in fatty tissues. These include mercury (mainly methyl mercury, the organic form of mercury), cadmium and lead. Most of these contaminants (POPs and mercury) are found in the food chain (i.e., in fish and fish-eating birds, as well as in other wild animals). Because of their persistence, they tend to accumulate in higher concentrations in predators and older animals. Careful statistical (factor) analysis of the Eastmain and Wemindji data confirmed that exposure to PCBs and pesticides occurs by way of traditional foods.
Concentrations of POPs and toxic metals were measured in the blood plasma of the Eastmain and Wemindji study participants. Since older adults (40 years and older) have consumed more wild animals during their lifetime, they generally show higher concentrations of PCBs, organochlorine pesticides and mercury in their bodies. However, these contaminants represent a health concern mainly for pregnant women and their babies, and young children. Fortunately, women of childbearing age and young children had relatively low levels of mercury, PCBs and organochlorine pesticides; neither were they a health concern for the majority of participants, perhaps with the exception of mercury. When combining the data for Eastmain, Wemindji and Mistissini, there is a suggestion in the present study of a small increase in blood pressure associated with mercury levels in blood and some negative impact on heart rate (beat) variability. Lead exposure is not a big issue in Eastmain and Wemindji, likely due to a decrease in the use of lead shot. Cadmium exposure (toxic to the kidneys) is mostly related to smoking, an avoidable source. Since some participants exceeded levels of concern for cadmium exposure, this reinforces the fact that people should quit smoking to avoid adverse health effects. Exposure to other industrial contaminants such as stain repellents and dioxins is similar to levels observed in other First Nations communities elsewhere in Canada, and shows similar associations with fish/game consumption and age, except for fireproofing agents which showed no association with consumption of traditional foods, suggesting other sources of exposure. Fire-proofed household goods are suspected.
Our findings suggest that exposure to environmental contaminants through the consumption of traditional foods still occurs in the Eastmain and Wemindji populations. The concentrations observed are not alarming but warrant monitoring, especially to track changes in contaminant levels associated with industrial developments (both remote and in Eeyou Istchee). However given the known benefits of traditional foods, their consumption should still be encouraged.
1.7 Health status
In this study, many clinical tests were carried out in order to provide a “snapshot” of the Eastmain and Wemindji population health status, with an emphasis on certain chronic diseases or health conditions that may be related to lifestyle habits as well as the environment. Osteoporosis is a condition that appears mostly in post-menopausal women and increases the risk of bone fractures. Fortunately, the bone ultrasound measurements in both communities indicated that the risk of breaking a bone appears to be relatively low among Eeyou women compared to Québec City females. Pooling data from all three communities visited, overt hypothyroidism seems higher than expected among both men and women. However, additional data following completion of the study would be necessary to draw firm conclusions regarding this issue.
Thickening of the arteries (atherosclerosis) is a condition responsible for heart attacks and stroke. It was estimated in 143 participants aged 40 years and older by measuring the thickness of the carotid artery (neck artery) by ultrasound. This analysis showed that artery thickness increased with age for both men and women, and overall, this measurement suggests increased subclinical atherosclerosis in Cree people compared to healthy Caucasians. In both communities, the estimated prevalence of high blood pressure is high (more than 35%), but comparison between onsite measurements and medical file information suggests that this condition is adequately diagnosed and stabilized for most people. High blood pressure was more frequent in older people, smokers, those showing abdominal obesity and high bad cholesterol levels, and in those most exposed to mercury. For blood lipids (fats), total cholesterol was high in only a small portion of the population, but the good cholesterol (HDL) concentrations could be improved relative to the bad cholesterol (LDL) levels, especially in obese people. The observed blood lipid profiles are rather similar to those obtained in a 1991 survey, and some lifestyles interventions could be undertaken to improve these blood lipid profiles.
Rates of global obesity and abdominal obesity were higher in both communities compared to the general Canadian population. In parallel, we observed high levels of plasma insulin, mainly among women and young girls in both communities. Reducing these and other known T2D risk factors needs urgent attention.
For all age groups, obesity and elevated blood insulin levels are unhealthy conditions that lead to illness and premature death. It is known that high-fat and high-sugar diets, coupled with low physical activity, are linked to these medical conditions. Therefore, intensification of the current promotion of a healthy diet and increased physical activity is recommended, especially among younger age groups.
1.8 Zoonoses
In this study, we looked at some diseases that could be transmitted from animals to humans (zoonoses). When somebody is infected by a microbe (bacterium, parasite or a virus; referred to as zoonotic agents), it is often possible to find traces of past infections in the blood (as antibodies) even many years after the acute infection episode is over. We evaluated the seroprevalence (i.e., presence of antibodies in blood serum reflecting a past exposure to infections) of ten zoonotic agents among the general population of Eastmain and Wemindji. Overall, seroprevalence rates were similar between the two communities. Nearly half the individuals tested (n = 251; 146 women, 105 men) were positive (n = 113) for at least one zoonosis. The highest rates were for the Leptospira sp. (23%) and Francisella tularensis (17%) bacteria, and the California serogroup viruses (JC and SSH viruses) (10%). The bacterium Coxiella burnetii and the parasites Toxoplasma gondii, Echinococcus granulosus, Toxocara canis, and Trichinella sp. had seroprevalence rates of 5% or less. Overall, a positive finding was related to age, gender, hunting and owning a dog. There was no medical history suggestive of overt diseases. Nonetheless, physicians should consider these agents when confronted with difficult or confusing diagnoses. In particular, the bacterial zoonoses should be ruled out in individuals with high or prolonged fever.
In general, the results of this study component show no alarming rates of zoonotic infections, or any need for immediate action. Nevertheless, hunters and trappers seem to more at risk and should be made aware of the symptoms of these types of infections and of safe procedures for handling dead animals.
1.9 Water
We also assessed the potential microbial (bacteria and parasites) contamination of drinking water collected from natural sources (mostly from springs) during June (Wemindji) and August (Eastmain) of 2007. Standard tests for detecting total coliforms, Escherichia coli and enterococci, as well as new molecular microbiology testing techniques, showed some modest biological contamination after both collection and storage (Bernier et al., 2009).
Water obtained from a spring, river or lake may contain some unwanted disease-causing microorganisms when indicators of fecal contamination are detected. As a simple preventive measure, it should be boiled for at least one minute before drinking.
1.10 Conclusion
Contaminants are not a major concern for the CBHSSJB, even though they are present in the food chain. Because of the environmental changes imposed by industrial development both remote and in Eeyou Istchee, we must continue monitoring these contaminants. However, being overweight and eating an unbalanced diet are by far more important health concerns that seem to require prompt preventive action. Based on the findings summarized above, the important messages are: do not smoke, be physically active, include vitamin-rich foods in your diet, keep eating traditional food items as they are healthy, and reduce eating foods known to be unhealthy such as high-sugar, high-fat industrially-prepared foods.
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