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Hypertension or high blood pressure (BP) is a prevalent and manageable chronic condition which is a significant contributor to the total global disease burden. Environmental chemicals, including mercury (Hg), may contribute to hypertension onset and development. Hg is a global health concern, listed by the World Health Organization (WHO) as a top ten chemical of public health concern. Most people are exposed to some level of Hg, with vulnerable groups, including Indigenous peoples and small-scale gold miners, at a higher risk for exposure. We published a systematic review and meta-analysis in 2018 showing a dose-response relationship between Hg exposure and hypertension. This critical review summarizes the biological effects of Hg (both organic and inorganic form) on the underlying mechanisms that may facilitate the onset and development of hypertension and related health outcomes and updates the association between Hg exposure (total Hg concentrations in hair) and BP outcomes. We also evaluated the weight of evidence using the Bradford Hill criteria. There is a strong dose-response relationship between Hg (both organic and inorganic) exposure and BP in animal studies and convincing evidence that Hg contributes to hypertension by causing structural and functional changes, vascular reactivity, vasoconstriction, atherosclerosis, dyslipidemia, and thrombosis. The underlying mechanisms are vast and include impairments in antioxidant defense mechanisms, increased ROS production, endothelial dysfunction, and alteration of the renin-angiotensin system. We found additional 16 recent epidemiological studies that have reported the relationship between Hg exposure and hypertension in the last 5 years. Strong evidence from epidemiological studies shows a positive association between Hg exposure and the risk of hypertension and elevated BP. The association is mixed at lower exposure levels but suggests that Hg can affect BP even at low doses when co-exposed with other metals. Further research is needed to develop robust conversion factors among different biomarkers and standardized measures of Hg exposure. Regulatory agencies should consider adopting a 2 µg/g hair Hg level as a cut-off for public health regulation, especially for adults older than child-bearing age., Competing Interests: Declarations. Conflict of interest: None of the authors has a conflict of interest to declare. Authorship: X.F.H., A.L., and H.M.C. conceived the study. X.F.H. and A.L. performed the literature searches. X.F.H. and A.L. screened articles for inclusion. X.F.H., A.L., and H.M.C. wrote the first draft of the manuscript. All authors revised the manuscript and approved the final version. Ethics of human subject participation: This study did not require ethical approval, as the data used have been published previously and are, hence, already in the public domain. Consent is not required when conducting a review., (© 2024. The Author(s).)

Understanding the patterns of chemical exposure among biota across a landscape is challenging due to the spatial heterogeneity and complexity of the sources, pathways, and fate of the different chemicals. While spatially-driven relationships between contaminant sources and biota body burdens of a single chemical are commonly modelled, there has been little effort on modelling chemical mixtures across multiple wildlife species in the Canadian Oil Sands region. In this study, we used spatial principal components analysis (sPCA) to assess spatial patterns of the body burdens of 22 metals and Potentially Toxic Elements (PTEs) in 492 individual wildlife, including fur-bearing mammals, colonial waterbirds, and amphibians collected from the Canadian Oil Sands region in Canada. Spatial analysis and mapping both indicate that some of the complex exposures in the studied biota are distributed randomly across a landscape, which suggests background or non-point source exposures. In contrast, the pattern of exposure for seven metals and PTEs, including mercury, vanadium, lead, rubidium, lithium, strontium, and barium, exhibited a clustered pattern to the east of the open-pit mining area and in regions downstream of oil sands development which indicates point-source input. This analysis demonstrated useful methods for integrating monitoring datasets and identifying sources and potential drivers of exposure to chemical mixtures in biota across a landscape. These results can be used to support an adaptive monitoring program by identifying regions needing additional monitoring, health impact assessments, and possible intervention strategies., Competing Interests: The authors have declared that no competing interests exist.

Triclosan is a broad-spectrum antimicrobial additive in consumer products that has been detected in human populations globally. The purpose of this study was to assess triclosan exposure among the Canadian population using urinary triclosan as a biomarker. Data from the Canadian Health Measures Survey (CHMS) that reported triclosan concentrations in 8195 urine samples collected from Cycle 2 (2009-2011) and Cycle 3 (2012-2013) were analyzed. Triclosan was detected in 69.8% of samples with the geometric mean concentrations of 16 μg/L (16 μg/g creatinine) for the total population, 13 μg/L (13 μg/g creatinine) for children (3-19 years of age), and 16 μg/L (17 μg/g creatinine) for adults. Triclosan concentrations significantly differed by age, income, education, and employment in healthcare occupations, but not by race/ethnicity, sex, region of residence, or drinking water preferences or sources. Linear regression models were used to identify factors associated with urinary triclosan concentration. Results showed that household income was associated with higher urinary triclosan concentrations in both children and adults. Employed in healthcare occupations were associated with higher urinary triclosan concentrations in adults. Triclosan exposure at the 99th percentile was below the Biomonitoring Equivalents based on reference dose, suggesting that health risks to the Canadian population from triclosan exposure were low., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Body burden of mercury has been linked to hypertension in populations exposed to high mercury levels., Objectives: We summarized, extracted, and pooled the results of published studies that investigated mercury biomarkers and hypertension or blood pressure (BP) measurements to examine this potential relationship., Methods: We searched PubMed, Embase, and TOXLINE and selected studies according to a priori defined inclusion criteria. Study quality was assessed by the Newcastle-Ottawa scale for cohort and case-control studies and the Quality Assessment Tool for cross-sectional studies. Study estimates were pooled using inverse-variance weighted random-effects models. Dose-response meta-analysis was performed with studies reporting hypertension and systolic BP for at least three mercury categories., Results: A total of 29 studies were included in the meta-analysis. The pooled odds ratio (OR) for hypertension, comparing the highest and lowest mercury exposure categories, was 1.35 [95% confidence interval (CI): 0.99, 1.83] for populations with hair mercury ≥2 μg/g in comparison with the OR of 1.12 (95% CI: 0.82, 1.52) for populations with hair mercury <2 μg/g. Positive associations were also observed for highest versus lowest mercury exposure categories on systolic and diastolic BP. Heterogeneity was observed for mercury species and exposure groups across different studies. Associations estimated using different mercury biomarkers generally agree with each other in the same study. A nonlinear dose-response relationship with an inflection point at 3 μg/g was identified, for both hypertension and systolic BP., Conclusions: A significant positive association between mercury and hypertension and between mercury and BP was identified. The exposure dose is an important factor in determining the toxic effects of mercury on hypertension. https://doi.org/10.1289/EHP2863.

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., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Methyl Mercury (MeHg) exposure is a global environmental health concern. Indigenous peoples around the world are susceptible to MeHg exposure from often higher fish consumption compared to general populations. The objective of this study was to estimate dietary exposure to methylmercury (MeHg) among First Nations living on-reserve in the province of Ontario, Canada. A total diet study was constructed based on a 24-h recall from the First Nations Food, Nutrition, and Environment Study (FNFNES), and measured contaminant concentrations from Health Canada for market foods, and FNFNES for traditional foods. A probabilistic assessment of annual and seasonal traditional food consumptions was conducted for 1429 adult participants. Results were compared to exposures in the general Canadian population and reference values from Health Canada for adults and women of childbearing age (ages 19-50). Results indicated traditional foods to be the primary contributor to the dietary total MeHg intake (72%). The average dietary total MeHg exposure in the First Nations population in Ontario (0.039μg/kg/d) was 1.6 times higher than the general Canadian population; however, the majority (97.8%) of the population was below the reference values. Mercury concentrations in participants' hair samples (n = 744) ranged from 0.03 to 13.54µg/g, with an average of 0.64µg/g (geometric average of 0.27µg/g). Less than 1% of the population had a hair mercury value above the 6µg/g level, and 1.3% of women of child bearing age had values greater than 2µg/g. Fish species contributing to the MeHg intake included pickerel-walleye, pike, perch and trout. Only 7.9% of the population met the recommended fish consumption rate of two, 3.5oz servings per week from the American Heart Association. Therefore, consumption of lower trophic level fish can be promoted to provide the maximum nutritional benefit with minimal risk of MeHg exposure., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Mercury pollution and its impacts on human health is of global concern. The authors of this paper were members of the Plenary Panel on Human Health in the 12th International Conference on Mercury as a Global Pollutant held in Korea in June 2015. The Panel was asked by the conference organizers to address two questions: what is the current understanding of the impacts of mercury exposure on human health and what information is needed to evaluate the effectiveness of the Minamata Convention in lowering exposure and preventing adverse effects. The authors conducted a critical review of the literature published since January 2012 and discussed the current state-of-knowledge in the following areas: environmental exposure and/or risk assessment; kinetics and biomonitoring; effects on children development; effects on adult general populations; effects on artisanal and small-scale gold miners (ASGM); effects on dental workers; risk of ethylmercury in thimerosal-containing vaccines; interactions with nutrients; genetic determinants and; risk communication and management. Knowledge gaps in each area were identified and recommendations for future research were made. The Panel concluded that more knowledge synthesis efforts are needed to translate the research results into management tools for health professionals and policy makers., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Inorganic and organic forms of arsenic (As), as well as omega-3 fatty acids were measured in 578 fish/seafood samples that belong to 15 species of commonly consumed seafood in Kuwait. Arsenic speciation data, with the toxicological profile of inorganic arsenic (iAs) and fish consumption rates were applied in a probabilistic risk assessment to estimate the risk from exposure to iAs. The nutritional benefits of omega-3-fatty acid levels in various species of fish were taken into consideration. Results showed that the mean daily intake of iAs through fish consumption among the Kuwaiti population was 0.058 µg/kg/day, and the 95th percentile was 0.15 µg/kg/day. Although the mean intake level did not exceed the incremental lifetime cancer risk (ILCR) at 1 × 10 -4 , the 95th percentile of iAs intake showed an ILCR of 2.7 × 10 -4 . Kuwaiti children (aged 6-12 years) were found to have a higher mean intake of iAs at 0.10 µg/kg/day with 68% of children in this category, exceeding the risk specific dose associated with an ILCR of 1 × 10 -4 . The fish species, hammor (grouper; Epinephelus coioides), is the top contributor to iAs intake, and tuna is the major source of omega 3-fatty acids for the Kuwaiti population.

For indigenous Arctic Canadians, traditional food consumption represents a key source of nutrients and environmental contaminants. Particularly, ingestion of marine mammal blubber and meat may lead to persistent organic pollutant levels and mercury intakes that exceed regulatory thresholds for sensitive populations. We investigated whether temporary adjustments to the consumption of traditional food derived from marine mammals appreciably impacted contaminant exposure and nutrient intakes among indigenous women of childbearing age. Such adjustments can be motivated by the desire to lower contaminant exposure or to increase nutrition, or by the diminishing availability of other traditional food sources. We combined the contaminant fate and transport model GloboPOP with the food chain bioaccumulation model ACC-Human Arctic to simulate polychlorinated biphenyl exposures in female 2007-08 Inuit Health Survey participants. We also calculated daily mercury and nutrient intake rates. Our results suggest that a temporary decrease in marine mammal consumption is largely ineffective at reducing exposure to polychlorinated biphenyls, because of their long elimination half-lives. In contrast, substitution of marine mammals was highly efficient at reducing mercury intake, but also appreciably lowered intakes of iron, manganese, selenium, and ω-3 polyunsaturated fatty acids. The impact of increasing intake of traditional food derived from marine mammals during childbearing age greatly depended on baseline consumption rates; replacement is ill-advised for those who already consume a lot of traditional food due to greater polychlorinated biphenyl and mercury exposures, while replacement was potentially beneficial for those with very limited marine mammal consumption due to increased nutrient intakes. Our calculations primarily suggest that considering baseline traditional food intake rates is critical to devising reproductive dietary adjustment strategies that maximize nutrient intake while minimizing environmental contaminant exposure., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Rice can accumulate methylmercury (MeHg) and rice consumption is the main route of MeHg exposure for the local population in Guizhou, China. However, inorganic Hg (IHg) load in human body is not comprehensively studied in highly Hg polluted areas such as Hg mining areas. This study is designed to evaluate human IHg exposure, related renal effects and possible pathways in Wanshan Hg mining area, Guizhou, Southwest China. Residents lived within 3 km to the mine waste heaps showed high Urine Hg (UHg) concentrations and the geometrical means (Geomean) of UHg were 8.29, 5.13, and 10.3 μg/g Creatinine (Cr) at site A, D, and E, respectively. It demonstrated a gradient of UHg concentrations with the distance from the pollution sources. A significantly positive correlation between paired results for UHg concentrations and serum creatinine (SCr) was observed in this study, but not for UHg and blood urea nitrogen (BUN). There are significant increases of SCr in two quartiles with high UHg concentrations. The results indicated that human IHg exposure may cause impairment of renal function. By calculation of Probable Daily Intake from different routes, we found that dietary intake is the main pathway of IHg exposure for the local population, rather than inhalation of Hg vapor., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: Since the 1990s, research has been carried out to monitor environmental contaminants and their effects on human health in the Arctic. Although evidence shows that Arctic indigenous peoples are exposed to higher levels of contaminants and do worse on several dimensions of health compared with other populations, the contribution of such exposures on adverse outcomes is unclear., Objective: The purpose of this review is to provide a synopsis of the published epidemiological literature that has examined association between environmental contaminants and health outcomes in Arctic indigenous populations., Design: A literature search was conducted in OVID Medline (1946-January 2014) using search terms that combined concepts of contaminant and indigenous populations in the Arctic. No language or date restrictions were applied. The reference lists of review articles were hand-searched., Results: Of 559 citations, 60 studies were relevant. The studies fell under the following categories: paediatric (n=18), reproductive health (n=18), obstetrics and gynaecology (n=9), cardiology (n=7), bone health (n=2), oncology (n=2), endocrinology (n=2) and other (n=2). All studies, except one from Arctic Finland, were either from Nunavik or Greenland. Most studies assessed polychlorinated biphenyls (n=43) and organochlorine pesticides (n=29). Fewer studies examined heavy metals, perfluorinated compounds, or polybrominated diphenyl ethers. Details of study results for each health category are provided., Conclusions: It is difficult to make conclusive statements about the effects of environmental contaminants on health due to mixed results, small number of studies and studies being restricted to a small number of regions. Meta-analytical synthesis of the evidence should be considered for priority contaminants and health outcomes. The following research gaps should be addressed in future studies: association of contaminants and health in other Arctic regions (i.e. Inuvialuit Settlement Region, Nunavut, Nunatsiavut, Alaska, European North and Russian North); assessment of contaminants on chronic diseases; inclusion of clinical endpoints in assessments; and assessment of the emerging contaminants of perfluorinated compounds and polybrominated diphenyl ethers.

Background: Blood lead levels (BLLs) were measured in the adult Inuit population of Nunavut, Northern Canada, during the Inuit Health Survey (IHS) in 2007-2008. Approximately 10% of the adult participants had BLL over the Health Canada's guidance of 100μg/L., Objectives: 1) To repeat the measurement of BLL among the IHS participants with high BLL and household members including pregnant women and children under 10years of age; 2) to measure lead (Pb) concentrations in environmental samples to identify potential sources and 3) to explore how Pb from environmental samples contributes to BLL using Pb stable isotopic analyses., Methods: Blood samples were collected from 100 adults and 56 children in 2012. A total of 169 environmental samples (tap water, house dust, paint, country food, soil, and ammunition) were collected from 14 houses from three communities where the IHS participants had the highest BLL. Total Pb concentrations and Pb isotope mass balance were determined by inductively coupled plasma-mass spectrometry (ICP-MS)., Results: The geometric mean of BLL was 43.1μg/L; BLL increased with age and was higher in adults than children (71.1 vs. 17.5μg/L). Median Pb concentrations in water (1.9μg/L) and dust (27.1μg/m(2) for wiped dust, 32.6mg/kg for vacuum dust coarse fraction, and 141.9mg/kg for vacuum dust fine fraction) were generally higher than in other parts of Canada. Median Pb concentrations of food and soil coarse and fine fractions were low (36.6μg/kg, 5.4mg/kg and 11.8mg/kg respectively); paint chips exceeded the Canadian guidelines in two houses (median: 3.8mg/kg). Discriminant analyses and isotope ratio analyses showed that ammunition and house dust are major sources of Pb in this study population., Conclusion: Analyses of Pb stable isotopes are useful to identify the routes of exposure to Pb. This approach can contribute to develop targeted public health programmes to prevent Pb exposure., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

There is increasing evidence that selenium (Se) has a significant effect on mercury (Hg) toxicology; however, Hg exposure risk assessments usually consider only the amount of Hg present in the environment or in food. On the basis of the present understanding of mechanisms of interaction between Se and Hg, the physiology/toxicology of Se, and the toxicology of Hg, we propose a new criterion for Se/Hg exposure assessment. This criterion, which is based on Se-Hg interactions, considers not only the toxicological consequences of Hg exposure but also the benefits and/or adverse effects of Se intake, especially the adverse effects related to a Se deficiency/excess. According to an illustrative assessment based on the new criterion and nine existing criteria, large knowledge gaps in the traditional assessments of exposure to Hg and/or Se were found, including those that assessed the interactions between Hg and Se. These results suggest that future assessments of Hg exposure (or Se intake) should include both Se and Hg.

Inuit living in the Arctic are exposed to elevated levels of environmental contaminants primarily due to long-range atmospheric transport. Blood sampling and contaminant biomonitoring was conducted as part of the International Polar Year Inuit Health Survey in 2007-2008. The body burden of metals (e.g. Cd, Pb) and persistent organic pollutants (e.g. PCBs, DDT & DDE, toxaphene, chlordane, PBDEs) were measured for Inuit participants (n=2172) from 36 communities in Nunavut, Nunatsiavut, and the Inuvialuit Settlement Region, in Canada. The geometric mean of blood concentrations for Cd, Pb, PCBs, DDE & DDT, toxaphene, and chlordane were higher than those in the Canadian general population. A total of 9% of study participants exceeded the intervention guideline of 100μgL(-1) for Pb, 11% of participants exceeded the trigger guideline of 5μgL(-1) for Cd, and 1% exceeded the intervention guideline of 100μgL(-1) for PCBs. Also, 3% of women of child-bearing age exceeded blood Pb of 100μgL(-1) while 28% of women of child-bearing age exceeded 5μgL(-1) of PCBs. This work showed that most Inuit Health Survey participants were below blood contaminant guidelines set by Health Canada but that metal and POP body burdens commonly exceed exposures observed in the general population of Canada., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Fish consumption is considered as the primary pathway of human methylmercury (MeHg) exposure. However, recent studies highlighted that, rice, rather than fish, is the main route of human MeHg exposure in Guizhou, inland China. China is considered as the largest anthropogenic source of mercury (Hg) emission in the world, which has led to serious environmental Hg pollution. But there are no comprehensive studies regarding this environmental health problem to evaluate human Hg exposure and associated health effects. This study aimed to estimate daily MeHg intake and health risk in 7 provinces in southern China, and to assess the relative contribution from rice and fish consumption. The average levels of total mercury (THg) and MeHg in rice samples were generally low at 10.1 ng·g⁻¹ and 2.47 ng·g⁻¹, respectively. But a total of 36 rice samples (12.7%) had THg concentration exceeding the national limit (20 ng·g⁻¹). Generally, rural population had significantly higher Probable Daily Intakes (PDIs) of MeHg than urban population from rice consumption and its relative contribution to MeHg exposure increased significantly from coastal to inland area. The averages of PDIs of MeHg were 0.020 μg·kg⁻¹·d⁻¹ and 0.028 μg·kg⁻¹·d⁻¹ for urban and rural population in southern China, respectively. Despite the serious environmental Hg pollutions in China, the general population in southern China had low risk of MeHg exposure. But rice is an important route of human MeHg exposure in southern China, especially for the rural population in inland area. The findings indicate that rice consumption should be considered when evaluating MeHg exposure in rice eating population in southern China., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Fish is a major source of harmful methylmercury (MeHg) and beneficial docosahexaenoic acid (DHA) in the developing brain. In this study, we investigated the correlations among maternal and umbilical cord (cord) MeHg and DHA levels at parturition, and mercury (Hg) concentration in 1-cm incremental segments hair samples which grew during gestation representing monthly MeHg exposure levels throughout the period. Whole blood Hg and plasma DHA levels were measured in blood sample pairs collected from 54 mothers at early gestation and parturition, and in cord blood. Maternal hair samples were collected at parturition, and Hg concentrations were measured in 1-cm incremental segments. Hg level in mothers at parturition was slightly lower than that at early gestation and the level in cord blood were approximately 1.9 times higher than that in mothers at parturition. On the other hand, DHA level in mothers at parturition was approximately 2.3 and 1.6 times higher than those in mothers at early gestation and in cord plasma, respectively. These results indicate that kinetics of these chemicals in mothers during gestation and placental transfer are completely different. However, Hg and DHA levels had significant positive correlation in fetal circulation. The cord blood Hg showed the strongest correlation with maternal hair Hg in the first 1-cm segment from the scalp at parturition (r=0.87), indicating that fetal MeHg level reflects maternal MeHg burden at late gestation. In contrast, maternal and cord plasma DHA concentrations at parturition showed the highest correlation coefficients with Hg in the fifth (r=0.43) and fourth (r=0.38) 1-cm hair segments, suggesting that maternal and fetal DHA levels reflects maternal fish intake during mid-gestation., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

There is concern that the traditional diet is a source of mercury exposure among Inuit in the Canadian Arctic. Mercury exposure in utero and in early childhood presents a risk to neurodevelopment. The objectives of the present study were to assess the dietary mercury exposure from traditional food among Inuit children 3 to 5 years of age in Nunavut, and evaluate the association between estimated dietary mercury intake and body burden. A cross-sectional Nunavut Inuit Child Health Survey was conducted in 2007 and 2008 which included assessment of dietary habits and children's hair mercury (Hg) levels. Further, an Inuit Adult Health Survey was conducted in the same years which included assessment of dietary habits and whole blood mercury concentrations. Traditional food samples were collected during this study and previously from the Canadian Arctic. Daily mercury intake from traditional food was calculated. Body mercury burden was determined using the hair mercury concentration. The geometric mean of children's hair Hg was 0.66 μg/g and varied by region. Nearly 25% of children had hair Hg concentrations equal to or higher than 2 μg/g (WHO reference level). There was a significant correlation between mercury levels in children's hair and that of the adults in the same household. For children, beluga muktuk, narwhal muktuk, ringed seal liver, fish, caribou meat and ringed seal meat were the major dietary sources of mercury. These food items together accounted for over 95% of total daily dietary mercury intake. A positive linear regression relationship between children's hair mercury levels and estimated dietary mercury intake was observed. Estimated intake in Baffin decreased by 30% compared to 20 years ago. Some traditional food items were significant sources of mercury to Inuit children in Nunavut. Although a reduction in the consumption of these diet items may be a way to reduce mercury intake, the nutritional, social and cultural benefits of traditional food and countervailing risks must be taken into account in risk mitigation., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Perfluorinated compounds (PFCs) have been detected in humans worldwide and are of health concern. This study measured the concentration of PFCs in composite samples collected for the 1998 Health Canada Total Diet Study and estimated dietary exposure for the Canadian population (older than 12 years of age) using previously collected dietary data (n = 1721). PFCs were detected in 8 samples including processed meats, preprepared foods, and peppers with a range of concentrations from 0.48 to 5.01 ng g(-1) (wet weight). 6:2 fluorotelomer unsaturated carboxylate (FTUCA) was detected in cold cuts at a concentration of 1.26 ng g(-1). Mean daily PFC exposure estimates ranged from 1.5 to 2.5 ng (kg of body weight)(-1). Perfluorinated carboxylates (PFCA C(7)-C(11)) contributed more to PFC exposure than either perfluorooctane sulfonate (PFOS) or FTUCA. Total PFCAs in cakes and cookies, lunchmeats, and green vegetables were the main contributors to dietary exposure, although these exposure levels were below the provisional tolerable daily intake provided by the German Drinking Water Commission. Dietary exposure to total PFCs has not changed over time, although the contribution of PFOS to total PFC exposure may have increased between 1998 and 2004. Further research on the sources of contamination of processed and preprepared foods is required. Dietary exposure to PFCs among Canadians poses minimal health risks based on current toxicological information.

Increasing evidence shows that persistent organic pollutants such as perfluorinated compounds (PFCs) are found in the Arctic ecosystem and their prevalence is causing human health concerns. The objective of this study was to estimate dietary exposure to PFCs among Inuit in northern Canada. Perfluorooctane sulfonate (PFOS), perfluorinated carboxylates (PFCA C(7)-C(11)) and fluorotelomer unsaturated carboxylic acids (6:2, 8:2 and 10:2 FTUCA) were measured in 68 traditional foods collected in Nunavut between 1997 and 1999. Total PFC concentrations were highest in caribou liver (mean+/-standard deviation; 6.2+/-5.5 ng g(-1)), ringed seal liver (minimum, maximum; 7.7, 10.2 ng g(-1)), polar bear meat (7.0 ng g(-1)), and beluga meat (minimum, maximum; 7.0, 5.8 ng g(-1)). Inuit food intake data from 24-h recalls conducted in Nunavut between 1997 and 1999 were used for the calculation of PFC exposure. Mean daily dietary exposure was calculated to range from 210 to 610 ng person(-1) (0.6-8.5 ng kg body weight(-1)) for 754 individuals. Dietary exposure to PFCs was statistically significantly higher in men in the 41-60 year age group (p<0.05) than younger men (<40 years old) and women from the same age group. Traditional foods contributed a higher percentage to PFC exposure than market foods in all age and gender groups. Caribou meat contributed 43-75% of daily PFC dietary exposure. Health risks associated with these estimated exposure levels are minimal based on current toxicological information available from animal feeding studies. However, it is important to monitor the concentrations of PFCs in key food items given that PFCA levels have been found to be increasing in the Canadian Arctic.

There is a rising global concern with regard to mercury (Hg) exposure among coastal populations. Two communities on the Bay of Fundy (New Brunswick, Canada) were assessed by hair monitoring and dietary methods. Average concentration of total Hg in hair was 0.70+/-0.55 mg/kg (N=91) at Grand Manan and 0.42+/-0.15 mg/kg (N=52) at St. Andrews/St. Stephen. Average daily consumption of fresh fish and shellfish was 50+/-40 g/day for Grand Manan and 19+/-19 g/day for St. Andrews/St. Stephen. Average daily total Hg intake estimated from the food frequency and 24-h recall questionnaires was 0.05+/-0.04 microg Hg/kg bw/day at Grand Manan and 0.03+/-0.04 microg Hg/kg bw/day at St. Andrews/St. Stephen. A significant correlation (r=0.47, P=0.002) between Hg intake and hair was observed for Grand Manan. Low Hg intakes and body burden can be attributed to the low Hg levels found in the species commonly consumed: haddock, canned tuna, lobster, and pollock (all below 0.2 microg/g wet weight). The results showed that Hg exposure in these Canadian coastal communities is low; fish with higher levels of Hg (shark, tuna, swordfish, pickerel, and bass) are not consumed locally.

Objective: To describe seafood consumption patterns in First Nations (FN) in British Columbia (BC) and examine lifestyle characteristics associated with seafood consumption; to identify the top ten most consumed seafood species and their contributions to EPA and DHA intake; and to estimate dietary exposure to methylmercury, polychlorinated biphenyls and dichlorodiphenyldichloroethylene.Design: Dietary and lifestyle data from the First Nations Food Nutrition and Environment Study, a cross-sectional study of 1103 FN living in twenty-one communities across eight ecozones in BC, Canada, were analysed. Seafood consumption was estimated using a traditional FFQ. Seafood samples were analysed for contaminant contents.Results: Seafood consumption patterns varied significantly across BC ecozones reflecting geographical diversity of seafood species. The top ten most consumed species represented 64 % of total seafood consumption by weight and contributed 69 % to the total EPA+DHA intake. Mean EPA+DHA intake was 660·5 mg/d in males, 404·3 mg/d in females; and 28 % of FN met the Recommended Intake (RI) of 500 mg/d. Salmon was the most preferred species. Seafood consumption was associated with higher fruit and vegetable consumption, lower smoking rate and increased physical activity. Dietary exposure to selected contaminants from seafood was negligible.Conclusions: In FN in BC, seafood continues to be an essential part of the contemporary diet. Seafood contributed significantly to reaching the RI for EPA+DHA and was associated with a healthier lifestyle. Given numerous health benefits, seafood should be promoted in FN. Efforts towards sustainability of fishing should be directed to maintain and improve access to fisheries for FN. [ABSTRACT FROM AUTHOR]