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In this study, we report the temporal trends of persistent organic pollutants (POPs) in 181 preschool Inuit children from Nunavik and the influence of confounding factors on blood contaminant levels. From 2006 to 2010, no significant trends were detected in Σpolychlorinated biphenyls (ΣPCBs), Σorganochlorine pesticides (ΣOPs), Σtoxaphene, and Σper- and polyfluoroalkyl substances (ΣPFASs). On the contrary, significant downward trends ranging from 9.3% to 14.3% per year were found for polybrominated diphenyl ethers (PBDEs). Breastfeeding was significantly associated with increased levels of POPs. Age was positively and significantly related to ΣPCBs, ΣOPs and Σtoxaphene. Compared with girls, boys had significantly higher concentrations of ΣPBDEs, but lower concentrations of ΣPFASs. Weight-for-height or body mass index z-scores were negatively and significantly related to ΣPCBs and ΣOPs. Passive smoking was positively and significantly associated with ΣOPs and Σtoxaphene. In conclusion, continued efforts to reduce contaminant exposure are needed to protect children's health and development.

ObjectivesTo assess dietary fatty acid intakes and to examine the relationship between dietary sources ofn-3 andn-6 PUFA and red-blood-cell (RBC)n-3 andn-6 PUFA composition.DesignA cross-sectional study. Dietary intakes were assessed with a 24 h dietary recall. A second recall was performed for 44 % of the children. Usual dietary intakes were estimated with the Software for Intake Distribution Estimation (SIDE). The fatty acid composition was measured in RBC membranes. Multivariate linear regression analyses were performed to explain RBCn-3 andn-6 PUFA concentrations.SettingChild-care centres in Nunavik, northern Québec, Canada.SubjectsOne hundred and sixty-seven Inuit children aged 11–53 months.ResultsA high proportion of the participants had inadequaten-3 andn-6 PUFA intakes (47·9 % and 93·5 %, respectively). Breast-feeding status and consumption of traditional food during the first 24 h dietary recall were significantly associated with RBCn-3 PUFA levels. Older children also tended to have higher RBCn-3 PUFA levels (P= 0·0528), whereas sex, infant formula status andn-3 PUFA dietary intakes were not associated with RBCn-3 PUFA concentrations. RBCn-6 PUFA concentrations were positively associated with breast-feeding status andn-6 PUFA dietary intakes, whereas age, sex and infant formula status were not.ConclusionsThe present findings highlight the fact that Inuit pre-school children are not consuming enoughn-3 andn-6 PUFA for optimum health. These observations call for actions to increase traditional food intake among Inuit children and to help them and their parents make healthier store-bought food choices.

The Inuit population of Nunavik (Canada) is exposed to immunotoxic organochlorines (OCs) mainly through the consumption of fish and marine mammal fat. We investigated the effect of perinatal exposure to polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (DDE) on the incidence of acute infections in Inuit infants. We reviewed the medical charts of a cohort of 199 Inuit infants during the first 12 months of life and evaluated the incidence rates of upper and lower respiratory tract infections (URTI and LRTIs, respectively), otitis media, and gastrointestinal (GI) infections. Maternal plasma during delivery and infant plasma at 7 months of age were sampled and assayed for PCBs and DDE. Compared to rates for infants in the first quartile of exposure to PCBs (least exposed), adjusted rate ratios for infants in higher quartiles ranged between 1.09 and 1.32 for URTIs, 0.99 and 1.39 for otitis, 1.52 and 1.89 for GI infections, and 1.16 and 1.68 for LRTIs during the first 6 months of follow-up. For all infections combined, the rate ratios ranged from 1.17 to 1.27. The effect size was similar for DDE exposure but was lower for the full 12-month follow-up. Globally, most rate ratios were > 1.0, but few were statistically significant (p < 0.05). No association was found when postnatal exposure was considered. These results show a possible association between prenatal exposure to OCs and acute infections early in life in this Inuit population.

In infants and children, iron deficiency (ID) can have several adverse effects on health including lethargy, alterations of immune defense mechanisms and impaired growth and cognitive development. The purpose of this study was to determine the prevalence of ID in a group of preschool Inuit children attending childcare centres in Nunavik using conventional measurements of iron status and a relatively new parameter, soluble transferrin receptor (sTfR). sTfR is especially useful in the presence of inflammation or infection. Two hundred forty-five Inuit children aged between 11 and 54 months (mean (SD) = 25.0 (9.6) months) were recruited between 2006 and 2010 in 10 of the 14 Nunavik communities. About half of the children were male and 52.3% (n=128) were less than 24 months old at the time of the study. Sixty-five children were excluded because they lacked one or more of the parameters under analysis, leaving 180 subjects for the assessment of iron status. ID defined either as serum ferritin 1...

High blood lead levels (BLLs) can be found in Inuit from Nunavik. At the same time, various nutrients such as calcium could lower lead absorption and toxicity. We examined the effect of dietary calcium intakes on BLLs in 245 preschool Inuit children attending childcare centres in Nunavik. Calcium intake was assessed with one 24-h dietary recall and BLLs were determined by inductively coupled plasma mass spectrometry in whole blood samples. Multiple imputation was performed to deal with missing data. Median blood lead concentration was 0.08 μmol/L. A high proportion of children did not meet the Estimated Average Requirement for vitamin D intake (73 %) and, to a lower extent, for calcium (20 %). Calcium intake was negatively associated with BLLs ( p = 0.0001) while child’s age and energy intake were positively associated with BLLs ( p = 0.015 and p = 0.024, respectively). Consuming traditional foods rich in calcium as well as milk and alternatives may protect against lead exposure.

Purpose: We assessed the impact of a nutrition program implemented in Nunavik childcare centres on Inuit children's food and dietary intakes.Methods: Two hundred and forty-five Inuit children (aged 25.0 ± 9.6 months) were recruited between 2006 and 2010 in Nunavik childcare centres. Dietary intakes were assessed using a single 24-hour dietary recall (n=217). We compared participants’ energy and nutrient intakes, and the proportions who met iron requirements and Canada's Food Guide – First Nations, Inuit and Métis recommendations, depending on whether or not they attended a childcare centre during the 24-hour dietary reference period.Results: Children who attended a childcare centre on the day of the recall had significantly higher intakes of omega-3 fatty acids, calcium, total iron, bioavailable iron, phosphorus, betacarotene, folate, pantothenic acid, riboflavin, and vitamin K, while a higher proportion of them met the recommended intake for total and bioavailable iron. The proportion of children who met the recommended servings for vegetables and fruit, grain products, and milk and alternatives was also significantly higher among participants who attended a childcare centre.Conclusions: The nutrition program was effective at improving these Inuit preschoolers’ diet.

Some evidence suggests that various diet components and nutrients, including vegetables, fruit and food-derived antioxidants, could mitigate contaminant exposure and/or adverse health effects of contaminants. To examine the effect of the consumption of tomato products on blood mercury levels in Inuit preschool children, 155 Inuit children (25.0 ± 9.1 months) were recruited from 2006–2008 in Nunavik childcare centers (northern Quebec, Canada). Food frequency questionnaires were completed at home and at the childcare center, and total blood mercury concentration was measured by inductively coupled plasma-mass spectrometry. Multivariate regression analysis was performed after multiple imputation. The median blood concentration of mercury was 9.5 nmol/L. Age, duration of breastfeeding, annual consumption frequency of seal meat, and monthly consumption frequency of tomato products were significant predictors of blood mercury levels, whereas annual consumption frequencies of beluga muktuk, walrus, Arctic char, and caribou meat were not. Each time a participant consumed tomato products during the month before the interview was associated with a 4.6% lower blood mercury level ( p = 0.0005). All other significant predictors in the model were positively associated with blood mercury levels. Further studies should explore interactions between consumption of healthy store-bought foods available in Arctic regions and contaminant exposure.

Arctic populations are exposed to substantial levels of environmental contaminants that can negatively affect children's health and development. Moreover, emerging contaminants have never been assessed in Inuit children. In this study, we document the biological exposure to toxic metals and legacy and emerging persistent organic pollutants (POPs) of 155 Inuit children (mean age 25.2 months) attending childcare centers in Nunavik. Blood samples were analyzed to determine concentrations of mercury, lead, polychlorinated biphenyls (PCBs), pesticides, brominated flame retardants [e.g., polybrominated diphenyl ethers (PBDEs)] and perfluoroalkyl and polyfluoroalkyl substances [PFASs; e.g. perfluorooctanesulfonate (PFOS) and perfluorooctane (PFOA)]. Lead [geometric mean (GM) 0.08 μmol/L], PCB-153 (GM 22.2 ng/g of lipid), BDE-47 (GM 184 ng/g of lipid), PFOS (GM 3369 ng/L), and PFOA (GM 1617 ng/L) were detected in all samples. Mercury (GM 9.8 nmol/L) was detected in nearly all blood samples (97%). Levels of metals and legacy POPs are consistent with the decreasing trend observed in Nunavik and in the Arctic. PBDE levels were higher than those observed in many children and adolescents around the world but lower than those reported in some U.S. cities. PFOS were present in lower concentrations than in Nunavimmiut adults. There is a clear need for continued biomonitoring of blood contaminant levels in this population, particularly for PBDEs and PFASs.

OBJECTIVE: To assess if vitamin A concentration in umbilical cord blood is associated with incidence and severity of respiratory infections in preschool Inuit children from Nunavik (Québec, Canada). METHOD: The medical charts of 305 children were reviewed from 0 to 5 years of age. The association between vitamin A concentration in umbilical cord plasma and the incidence rates of acute otitis media (AOM), lower respiratory tract infections (LRTIs) and hospitalization rates for LRTIs was evaluated using Poisson regression. RESULTS: Compared to children with vitamin A concentration >-20 μg/dl, adjusted rate ratios (RR) for children below 20 μg/dl ranged between 1.06–1.62 for AOM, 1.12–1.34 for LRTIs, and 1.09–1.43 for hospitalization for LRTIs. Most RRs were statistically significant for AOM and LRTIs, but not for hospitalization for LRTIs. CONCLUSION: Neonatal vitamin A deficiency appears to be a significant risk factor for AOM and LRTIs in this population.

OBJECTIVE: Inuit children from around the world are burdened by a high rate of infectious diseases. The objective of this study was to evaluate the incidence rate of infections in Inuit preschool children from Nunavik (Northern Québec). METHODS: The medical chart of 354 children from a previously recruited cohort was reviewed for the first five years of life. All outpatient visits that led to a diagnosis of acute infection and all admissions for acute infections were recorded. RESULTS: Rates of outpatient visits for acute otitis media (AOM) were 2314, 2300, and 732 events/1000 child-years for children 0–11 months, 12–23 months, and 2–4 years, respectively. Rates of outpatient visits for lower respiratory tract infections (LRTI) were 1385, 930, and 328 events/1000 child-years, respectively. Rates of hospitalization for pneumonia were 198, 119, and 31 events/1000 child-years, respectively. CONCLUSION: Inuit children from Nunavik have high rates of AOM and LRTI. Such rates were higher than that of other non-native North-American populations previously published. Admission for LRTI is up to 10 times more frequent in Nunavik compared to other Canadian populations.

It is well known that Inuit children from Canada, United States, and Greenland suffer from a high incidence of respiratory infections, and many authors have identified higher rates of ear infections and lower respiratory tract infections (LRTIs) in Inuit populations compared with Caucasian populations (Banerji et al. 2001; Bluestone 1998; Curns et al. 2002; Davidson et al. 1994; Holman et al. 2001; Karron et al. 1999; Koch et al. 2002; Ling et al. 1969; Lowther et al. 2000; Wainwright 1996). Among the factors suspected to be involved in this phenomenon, perinatal exposure to persistent organic pollutants has been implicated (Dallaire et al. 2004; Dewailly et al. 2000). The immunotoxic potential of some organochlorine compounds (OCs), such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs), is well known (Belles-Isles et al. 2002; Chang et al. 1982; Hoffman et al. 1986; Lu and Wu 1985; Neubert et al. 1992; Tryphonas et al. 1991a, 1991b). Although their production and use are now banned in many countries, a significant proportion of what has been emitted in the environment is still present in the biota of almost every region of the world (Braune et al. 1999; Burkow and Kallenborn 2000; Macdonald et al. 2000). The high degree of chlorination of OCs renders them resistant to biodegradation. They accumulate in adipose tissues of living organisms and are biomagnified in the food chain (Evans et al. 1991). The highest plasma concentrations were observed in top predator species (Braune et al. 1999; Muir et al. 1999; Skaare et al. 2000) and in humans with seafood-rich diets (Bjerregaard et al. 2001; Dewailly et al. 1993; Humphrey et al. 2000; Sjodin et al. 2000). The Nunavik region is located in the northernmost part of the province of Quebec, Canada. Around 9,600 Inuit inhabit 14 Inuit communities spread out on the coastline of Hudson Bay, the Hudson Strait, and the Ungava Bay. For cultural and economical reasons, carnivorous fish and marine mammals constitute an important part of the diet of the Inuit population of Nunavik. Their exposure to food-chain contaminants, such as OCs, is thus proportionally high. Several studies have identified markedly higher concentrations of OCs in adult blood, umbilical cord blood, and breast milk of Nunavik inhabitants, compared with those of the mostly Caucasian southern Quebec population (Ayotte et al. 1997, 2003; Dewailly et al. 1993; Muckle et al. 1998, 2001b; Rhainds et al. 1999). In 2000, we published a first study showing an association between perinatal exposure to OCs and acute otitis media (AOM) in Nunavik Inuit infants (Dewailly et al. 2000). To further document this association, we investigated the relation between maternal OC concentrations and acute respiratory and gastrointestinal infections in a second cohort of 199 infants of the same population (Dallaire et al. 2004). We found that OC concentrations in maternal plasma were positively associated with incidence of acute infections during the first 6 months of life, but not afterward. The number of subjects was small, however, and the associations were not always statistically significant. To clarify the possible link between prenatal exposure to OCs and infections in this population, we report here the association between PCB-153 concentrations in umbilical cord blood and incidence rate of acute respiratory tract infections in a third cohort of 343 preschool children of Nunavik born between 1993 and 1996.

Objectives. To describe traditional food (TF) consumption and to evaluate its impact on nutrient intakes of preschool Inuit children from Nunavik. Design. A cross-sectional study. Methods. Dietary intakes of children were assessed with a single 24-hour recall (n=217). TF consumption at home and at the childcare centres was compared. Differences in children’s nutrient intakes when consuming or not consuming at least 1 TF item were examined using ANCOVA. Results. A total of 245 children attending childcare centres in 10 communities of Nunavik were recruited between 2006 and 2010. The children’s mean age was 25.0±9.6 months (11-54 months). Thirty-six percent of children had consumed at least 1 TF item on the day of the recall. TF contributed to 2.6% of total energy intake. Caribou and Arctic char were the most reported TF species. Land animals and fish/shellfish were the main contributors to energy intake from TF (38 and 33%, respectively). In spite of a low TF intake, children who consumed TF had significantly (p