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Indigenous peoples have elevated risk of lead (Pb) exposure as hunted traditional food can be contaminated with lead-containing ammunition. Recent scientific consensus states that there is no threshold level for Pb exposure. The objective of this study was to estimate dietary exposure to Pb among First Nations living on-reserve in the province of Ontario, Canada. A total diet study was constructed based on a 24-h recall and Pb concentrations for traditional foods from the First Nations Food, Nutrition, and Environment Study (FNFNES) and Pb concentrations in market foods from Health Canada. A probabilistic assessment of annual and seasonal traditional food consumption was conducted. Results indicate that traditional foods, particularly moose and deer meat. are the primary source of dietary Pb intake (73%), despite providing only 1.8% of the average caloric intake. The average dietary Pb exposure (0.21μg/kg/d) in the First Nations population in Ontario was 1.7 times higher than the dietary Pb exposure in the general Canadian population. Pb intake was associated with an estimated average increase in systolic blood pressure of 1.2mmHg. These results indicate that consumption of foods hunted with Pb containing ammunition and shot puts the population at elevated risk of Pb toxicity.

Consumption of fish and n-3 fatty acids (n-3 FAs) has been postulated to prevent type 2 diabetes (T2D).Objective: To explore the association between self-reported T2D and fish consumption, dietary n-3 FAs, and persistent organic pollutants (POP) intake in a regionally representative sample of First Nations (FNs) in Manitoba.Design: Data from the cross-sectional First Nations Food, Nutrition and Environment Study (FNFNES) collected from 706 members of 8 Manitoba FNs in 2010 were used. Household interviews were used to collect social and lifestyle data. The consumption of fish was estimated using a traditional food frequency questionnaire. Fish samples were analyzed for the presence of POP. Multiple logistic regression models adjusted for potential risk factors for T2D were developed.Results: A negative, dose–response relationship was found between fish intake and self-reported T2D. Fish consumptions of 2–3 portions per month and ≥1/week were inversely associated with T2D with odds ratio (OR) values of 0.51 (95% CI: 0.28–0.91) and 0.40 (95% CI: 0.19–0.82), respectively, compared with no fish intake. Similarly, intake of n-3 FAs was negatively associated with T2D (OR = 0.48 (95% CI: 0.30–0.77). Dietary POP intake was not associated with T2D.Conclusion: These findings suggest that the consumption of traditionally harvested fish may have a beneficial effect on T2D in Manitoba FNs.

Background First Nations (FNs) populations in Canada experience a disproportionally higher rate of obesity and type 2 diabetes (T2D) compared to the general population. Recent data suggest that a high consumption of fish may help prevent T2D. On the other hand, fish might also be a potential source of environmental contaminants which could potentially be a risk factor for T2D. Objective To investigate the potential associations between self-reported T2D and consumption of locally-harvested fish, dietary long-chain omega-3 fatty acids (n-3FAs) and persistent organic pollutants intake among adult FNs living on reserve in Ontario. Design Data from the First Nations Food Nutrition and Environment Study, which included a cross-sectional study of 1429 Ontario FNs adults living in 18 communities across 4 ecozones in 2012 were analyzed. Social and lifestyle data were collected using household interviews. The consumption of locally-harvested fish was estimated using a traditional food frequency questionnaire along with portion size information obtained from 24hr recalls. Fish samples were analyzed for the presence of contaminants including dichlorodiphenyldichloroethylene (DDE) and polychlorinated biphenyls (PCBs). Dietary intakes of DDE and PCBs were estimated using community-specific levels of DDE/PCBs in fish species. Multiple logistic regression models adjusted for potential covariates including age, gender, body mass index, physical activity, total energy intake, smoking, and education were developed. Results The prevalence of T2D in Ontario FNs was 24.4%. A significant positive association between fish consumption of one portion per week and more and T2D compared to no fish consumption was found (OR=2.5 (95% CI: 1.38–4.58). Dietary DDE and PCBs intake was positively associated with T2D (OR=1.09 (95%CI: 1.05–1.75) for DDE and OR=1.07 (95%CI: 1.004–1.27) for PCBs) per unit increase in DDE/PCBs while n-3-FAs intake, adjusted for DDE/PCBs intake, showed an inverse effect against T2D among older individuals (OR=0.86 (95% CI: 0.46–0.99). Conclusion Our results support previous findings that exposure to DDE and PCBs may increase the risk of T2D. Elevated levels of contaminants in fish may counteract with potentially beneficial effects of n-3FAs from fish consumption. However, the overall health benefits of high consumption of fish with a high n-3 FAs content may outweigh the adverse effect of contaminants.

This paper describes a network of three interconnected, multidisciplinary research projects designed to investigate environmental health issues faced by First Nations in Canada. These projects, developed in collaboration with academia, used a participatory approach meant to build capacity, raise awareness, and initiate change. The first project, which began in British Columbia in 2008, gathered information on the traditional diet; for example, its composition, nutritional quality, and potential for chemical exposure. This 10-year, Canada-wide project served as a model for two follow-up projects: one on biomonitoring and another on indoor air quality. All three projects provided community ownership over the data and communicated results in a culturally sensitive manner to encourage interest in research and initiate risk reduction activities. The Assembly of First Nations, a national advocacy organization representing over 630 First Nations communities across Canada, participated in all aspects of t...

Objectives. To review the current literature to determine if there is a case for examining the presence of toxins in traditional foods and the environment as a possible risk factor for type 2 diabetes in Canadian Aboriginal populations. Study design. Literature review. Methods. The scientific literature on possible causes of type 2 diabetes in Aboriginal populations in Canada was reviewed. Potential exposure through food and water to environmental toxins such as methylmercury, arsenic, persistent organic pollutants (POPs), including bisphenol A and phthalates, as well as Aboriginal lifestyle and composition of the traditional diet is discussed. Results. There is growing evidence to suggest that environmental toxins may be associated with noninsulin- dependent diabetes mellitus (type 2 diabetes), which many consider to be endemic worldwide. In Canada, diabetes has reached epidemic proportions, especially among Aboriginal populations. Based on both molecular and pathological findings, some toxins found in the environment interfere with the functioning of the pancreas’ islets of Langerhans cells, and consequently they affect insulin production. In addition, there is new evidence suggesting that obesity may be linked to endocrine disruptors, thus increasing the likelihood that obesity in itself may not be a chief risk factor for diabetes. Conclusions. Diabetes prevalence rates among First Nations, Inuit and Metis populations are 3–5 times higher than the general population. Accepted risk factors such as diet, lifestyle and genetics do not fully explain this phenomenon. However, as many environmental toxins bioaccumulate in the food chain and are found in wild game and fish traditionally harvested and consumed by Aboriginal peoples, these chemicals could present health risks not yet fully explored. As there is not enough evidence to rule out this possibility, further studies are suggested. If correct, such environmental risk factors, especially if they are encountered early in life, would have implications on Aboriginal public health. (Int J Circumpolar Health 2009; 68(4):316–326) Keywords: Aboriginal, diabetes mellitus type 2, risk factors, dietary proteins, environmental toxins, public health

The effect of a cyclone (Ami, January 2003) on drinking-water quality on the island of Vanua Levu, Fiji was investigated. Following the cyclone nearly three-quarters of the samples analysed did not conform to World Health Organisation (WHO) guideline values for safe drinking-water in terms of chlorine residual, total and faecal coliforms, and turbidity. Turbidity and total coliform levels significantly increased (up 56 and 62 per cent, respectively) from pre-cyclone levels, which was likely due to the large amounts of silt and debris entering water-supply sources during the cyclone. The utility found it difficult to maintain a reliable supply of treated water in the aftermath of the disaster. Communities were unaware they were drinking water that had not been adequately treated. Circumstances permitted this cyclone to be used as a case study to assess whether a simple paper-strip water-quality test (the hydrogen sulphide, H(2)S) kit could be distributed and used for community-based monitoring following such a disaster event to better protect public health. The H(2)S test results correlated well with faecal and total coliform results as found in previous studies. A small percentage of samples (about 10 per cent) tested positive for faecal and total coliforms but did not test positive in the H(2)S test. It was concluded that the H(2)S test would be well suited to wider use, especially in the absence of water-quality monitoring capabilities for outer island groups as it is inexpensive and easy to use, thus enabling communities and community health workers with minimal training to test their own water supplies without outside assistance. The importance of public education before and after natural disasters is also discussed.

This study investigated prostate cancer screening practices using prostate specific antigen testing (PSA), digital rectal examination (DRE), and transrectal ultrasonography (TRUS) by primary care physicians in Missouri. In 1993, a mail survey was sent to a stratified random sample of 750 physicians whose primary specialty was general practice, family practice, or internal medicine. Three separate mailings resulted in an overall adjusted response rate of 60 percent. Ninety-five percent of physicians were more inclined to use PSA compared with three years previously, with only 45 percent of physicians more inclined to use DRE. An increase in the use of PSA following a negative DRE was reported by 85 percent and a greater inclination to use TRUS following a positive PSA was reported by 90 percent Eighty-six percent agreed with the American Cancer Society (ACS) guidelines on prostate cancer screening. Using logistic regression adjusted across levels of demographic and practice factors, prevalence odds ratios were derived with results indicating that agreement with ACS guidelines and being in private practice are strong predictors of a physician's inclination to routinely screen asymptomatic patients for prostate cancer. Our findings have provided baseline information on prostate cancer screening in Missouri and suggest that primary care physicians view PSA testing as a useful procedure and appear to be using it in a manner similar to the general pattern seen across the country.

Few studies have examined indoor air quality in First Nations communities and its impact on cardiorespiratory health. To address this need, we conducted a crossover study on a First Nations reserve in Manitoba, Canada, including 37 residents in 20 homes. Each home received an electrostatic air filter and a placebo filter for 1 week in random order, and lung function, blood pressure, and endothelial function measures were collected at the beginning and end of each week. Indoor air pollutants were monitored throughout the study period. Indoor PM2.5 decreased substantially during air filter weeks relative to placebo (mean difference: 37 μg/m(3) , 95% CI: 10, 64) but remained approximately five times greater than outdoor concentrations owing to a high prevalence of indoor smoking. On average, air filter use was associated with a 217-ml (95% CI: 23, 410) increase in forced expiratory volume in 1 s, a 7.9-mm Hg (95% CI: -17, 0.82) decrease in systolic blood pressure, and a 4.5-mm Hg (95% CI: -11, 2.4) decrease in diastolic blood pressure. Consistent inverse associations were also observed between indoor PM2.5 and lung function. In general, our findings suggest that reducing indoor PM2.5 may contribute to improved lung function in First Nations communities.Indoor air quality is known to contribute to adverse cardiorespiratory health, but few studies have examined indoor air quality in First Nations communities. Our findings suggest that indoor PM2.5 may contribute to reduced lung function and that portable air filters may help to alleviate these effects by effectively reducing indoor levels of particulate matter.

This paper describes a study undertaken to: (1) determine the prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworm infections and nutritional status among Pacific Island school children; (2) identify factors influencing helminthiasis; (3) identify interventions to improve school health. A total of 3,683 children aged 5-12 years attending 27 primary schools in 13 Pacific Island countries were surveyed along with school environmental data. Stool samples were collected from 1996 children (54.2%) and analysed for ova and helminths. Total prevalence of helminthiasis was 32.8%. Anaemia prevalence was 12.4%. Children with helminthiasis and anaemia were found to be 8.7 times more likely to be stunted and 4.3 times more likely to be underweight than non-anaemic and non-infected children. Four significant environmental influences on helminthiasis were identified: (1) an inadequate water supply; (2); availability of a school canteen; (3) regular water/sanitation maintenance regimes; and (4) overcrowded classrooms. Helminthiasis was found to be strongly associated with anaemia, stunting and underweight and environmental influences identified. Although mass anti-helminthic drug administrations (MDA) have been taking place, reinfection is common as drug therapy alone is not enough. Programme effectiveness depends upon upgrading school environments to include an adequate water supply, controlled food preparation/provision, well-maintained water/sanitation facilities and class sizes of 30 students or less.

Continuous low-level basaltic volcanic activity, from Yasur Volcano in Tanna, and Marum and Benbow vents on Ambrym, occurred for as long as records have been kept in Vanuatu. The potential chronic health implications for the inhabitants of these two areas were investigated in a preliminary environmental sampling program. The focus was particularly on fluoride and other volcanic gas-derived chemical contamination in areas surrounding the volcanic centres. Little immediate contamination of the environment was evident for areas affected by volcanic ash and gas on Tanna, with water fluoride concentrations being elevated (to 0.42 mg x l(-1)) only within a lake adjacent to the active volcanic cone. Selected re-sampling in April 2001 following the long active phase of Yasur, revealed higher F levels in surface waters (to 1.05 mg x l(-1)). Analysis of cow rib bone and teeth indicated a possible long-term accumulation of F in grazing animals, which probably consume F-bearing volcanic ash and gas hydrates on the surface of plant leaves. No human impacts (including stress and respiratory problems) were noted, probably due to the constant and familiar low-level activity, plus the coarse nature of most ash ejecta. Ambrym appears to be a more F-concentrated system than Tanna, with volcanic ash containing 281 total and 36.7-43.6 soluble mg F x kg(-1) (cf. 178 total and 7.3-9.1 soluble mg F x kg(-1) on Tanna), and water levels reaching up to 2.8 mg F x l(-1) in rainwater tanks. The drinking water F levels on Ambrym are higher than WHO recommended levels, despite the being sampled during a substantial lull in eruptive activity, and signal potential for chronic dental and skeletal fluorosis.

The determinants of education achievement for a sample of peasants on the Yucatan Peninsula in Mexico are examined by means of three general factors: (1) family background, (2) personal characteristics, and (3) years of schooling actually available. The final model clarifies the interactions among these factors, and explains a large proportion of the variance in educational achievement.

Rats handled between trials during shuttle avoidance training were superior to those not handled on several measures of avoidance learning; handled rats were nonetheless inferior to those receiving one-way training. A second experiment clearly demonstrated that differences between shuttle and one-way avoidance could not be attributed to differences in handling. Furthermore, hypotheses which explained poor shuttle avoidance by reference to either competing freezing responses or the necessity of entering a previously shocked compartment were by themselves unable to account for the present findings. A modification and synthesis of these hypotheses was proposed to provide a better account of the present data. It was suggested that freezing will occur only in the presence of fear-motivated conflict and that conflict is present only when a new response is required which is opposed to a previously successful response.

Transfer of a learned discrimination along the size dimension was studied in groups of American and African tribal children. The language spoken by the African children contains an asymmetry in the expression of size comparisons that is not present in English. Contrary to theories of linguistic mediation of choice behavior, transfer choices were not related to the differing linguistic patterns; however, initial choices and post-test descriptions of choices were so related.

Learning of a modified paired-associate task was studied in 144 school children. The type of stimulus material (pictures-words), the number of response alternatives (2–4), the matching of stimuli and response alternatives (Rule-Random), and the grade of the Ss (3rd-5th), all influenced the rate of learning. Interactions among these variables indicated that picture stimuli are relatively more helpful to the younger children, and the presence of a category reduces the relative advantage of pictures over words. An interaction implying that older Ss were better able to use the categorical material was absent. Analysis of the Two-Choice, Random data in terms of Bower's all-ornone learning model provided an adequate description of the course of learning. Deviations from the model in the other conditions suggest added processes are involved.