Concentrations of tetanus and diphtheria antibodies in vaccinated Greenlandic children aged 7-12 years exposed to marine pollutants, a cross sectional study.

Previous studies have shown immunotoxic effects of environmental chemicals, and the European Food Safety Authority (EFSA) recently identified a need for more studies on PFAS immunotoxicity in different populations. In the Arctic, populations are exposed to several environmental chemicals through marine diet, and the objective of this study was therefore to examine the association between Greenlandic children's exposure to major environmental chemicals and their concentrations of diphtheria and tetanus vaccine antibodies after vaccination. The study includes cross-sectional data from Greenlandic children aged 7-12 years examined during 2012-2015. A total of 338 children were eligible for the study, and 175 of these had available vaccination records. A parent or guardian participated in a structured interview, and a blood sample from the child was analyzed for specific antibodies against diphtheria and tetanus as well as perfluoroalkyl substances (PFASs), polychlorinated biphenyls (PCBs) and total mercury. Furthermore, for a subgroup, blood samples from pregnancy were available and analyzed for environmental contaminants. The associations between the environmental exposures and antibody concentrations and odds of having antibody concentrations below the protective level were examined in linear and logistic regression models. In crude analyses, elevated concentrations of some of the contaminants were associated with higher concentrations of diphtheria and tetanus antibodies, but the associations were reversed when adjusting for area of residence, and duration of being breastfed and including children with a known vaccination date only. Each 1 ng/mL increase in serum concentrations of perfluorohexane sulfonic acid (PFHxS) and perfluorooctane sulfonic acid (PFOS) was associated with decreases of 78 % (95 % CI: 25-94 %) and 9 % (95 % CI: 2-16 %), respectively, in diphtheria antibody concentrations. Exposure to PCBs and all PFASs was associated with markedly increased odds of having diphtheria antibody concentrations below the protective level. For each 1 ng/mL increase in serum concentrations of PFHxS, PFOS, perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA), odds of not having protective levels of diphtheria antibodies were increased 6.44 times (95 % CI: 1.51-27.36), 1.14 times (95 % CI: 1.04-1.26), 1.96 times (95 % CI: 1.07-3.60), and 5.08 times (95 % CI: 1.32-19.51, respectively. No consistent associations were seen between maternal contaminant concentrations and vaccine antibody concentrations. In conclusion, we found that increased exposure to environmental chemicals among children in this Arctic population were associated with a decrease in post-vaccination antibody concentrations and with increased odds of not being protected against diphtheria despite appropriate vaccination. These findings emphasize the risk of environmental chemical exposures also in this Arctic population.

Environmental chemical exposures among Greenlandic children in relation to diet and residence.

The objective of this study was to identify geographic, dietary, and other predictors for childhood exposure to perfluoroalkyl substances (PFASs), polychlorinated biphenyls (PCBs), and methylmercury in Greenlandic children. The study includes cross-sectional data from 367 Greenlandic children aged 7 to 12 years examined during 2012-2015. A parent or guardian participated in a structured interview, and a blood sample from the child was analysed for PFASs, PCBs and total mercury. Predictors for the environmental exposures were identified using linear regression. Area of residence was found to have the strongest explanatory power, accounting for 24% to 68% of the variance in the serum concentrations. Information about diet was available for two-thirds of the children, and among these, consumption of traditional Greenlandic food accounted for 2% to 10% of the variance in the biomarker concentrations. Models including all predictors associated with at least one of the environmental chemicals explained 19% to 54% of the total variance. In conclusion, area is a likely proxy for a traditional marine diet, and together area and diet constitute the most important predictors of exposure to methylmercury, PCBs and PFASs among Greenlandic children.

Persistent organic pollutants and haematological markers in Greenlandic pregnant women: the ACCEPT sub-study.

The Arctic populations have high blood concentrations of persistent organic pollutants (POPs). Exposure to POPs was related to adverse health effects e.g. immune, neurological and reproductive systems. This study investigates associations between serum POP levels and haematological markers in Greenlandic pregnant women. This cross-sectional study included 189 women enrolled in 2010-2011 at the Greenlandic West coast by the inclusion criteria ≥18 years of age and had lived for 50% or more of their life in Greenland. The associations between the sum of the POP variables polychlorinated biphenyls (sumPCBs), organochlorine pesticides (sumOCPs), perfluoroalkylated substances (sumPFASs) and 24 haematological markers were analysed using linear regression adjusted for age, pre-pregnancy BMI, parity, gestation week, plasma-cotinine and alcohol intake. It showed a significantly inverse association between several haematological markers (eosinophil, lymphocyte, neutrophil and white blood cells) and sumPCBs, sumOCPs and sumPFASs. In addition, the monocyte, mean corpuscular haemoglobin concentration, plateletcrit and platelet count markers were significantly inversely associated with sumPFASs, but the haematocrit and mean erythrocyte corpuscular volume were positively associated with sumPFASs. In conclusion, exposure to POPs influenced several haematological markers, especially cell count parameters, suggesting immunosuppressive potential of POPs in Greenlandic pregnant women. The data need further investigations.

Exposure to perfluoroalkyl substances during pregnancy and child behaviour at 5 to 9years of age.

We examined associations between prenatal exposure to perfluorohexane sulfonic acid (PFHxS), perfluoroheptanoic acid (PFHpA), perfluorononanoic acid (PFNA), and perfluorodecanic acid (PFDA) - and child behaviour (SDQ-total) and hyperactivity (sub-scale) at 5-9years of age in birth cohorts from Greenland and Ukraine. Pregnancy serum samples (N=1023) were analysed for perfluoroalkyl substances (PFASs) and categorised into tertiles and also used as continuous exposure variables. Problem behaviour and hyperactivity were assessed, using the Strength and Difficulties Questionnaire (SDQ) and categorised as normal/borderline and abnormal. Associations were analysed using multiple logistic and linear regression. High compared to low prenatal PFHxS exposure was associated with 1.16 (95% confidence interval (CI): 0.08; 2.25) point higher SDQ-total (more problem behaviour) in Greenland and 0.80 (CI: 0.06; 1.54) point higher SDQ-total in the combined analyses, whereas no association was present in Ukraine alone. One natural log-unit increase in prenatal PFNA exposure was associated with 0.90 (CI: 0.10; 1.71) points higher SDQ-total in Greenland and 0.72 (CI: 0.13; 1.31) points higher in the combined analysis and no association in Ukraine. Prenatal PFAS exposure was unrelated to problem behaviour (abnormal SDQ-total). In the combined analysis, odds ratio (OR) (CI) for hyperactivity was 1.8 (1.0; 3.2) for one natural log-unit increase in prenatal PFNA and 1.7 (1.0; 3.1) for one natural log-unit increase in prenatal PFDA exposure. Findings are compatible with weak effects on child behaviour of prenatal exposure to some PFASs although spurious results are not entirely unlikely. The associations were strongest in Greenland.

Prenatal and Postnatal PCB-153 and p,p'-DDE Exposures and Behavior Scores at 5­9 Years of Age among Children in Greenland and Ukraine.

BACKGROUND: Studies have reported some evidence of adverse effects of organochlorine exposures on child development, but the results have been inconsistent, and few studies have evaluated associations with child behavior. OBJECTIVE: We investigated the association between prenatal and early-life exposures to 2,2',4,4',5,5'-hexachlorobiphenyl (PCB-153) and 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE) and behaviors in children between 5 and 9 y of age. METHODS: In the Biopersistent organochlorines in diet and human fertility: Epidemiologic studies of time to pregnancy and semen quality in Inuit and European populations (INUENDO) cohort, consisting of mother-child pairs from Greenland and Ukraine (n=1,018), maternal serum PCB-153 and p,p'-DDE concentrations were measured during pregnancy, and cumulative postnatal exposures during the first 12 months after delivery were estimated using a pharmacokinetic model. Parents completed the Strengths and Difficulties Questionnaire (SDQ), and children's behaviors were dichotomized as abnormal (high) versus normal/borderline for five SDQ subscales and the total difficulties score. RESULTS: The total difficulties score, an overall measure of abnormal behavior, was not clearly associated with pre- or postnatal exposures to PCB-153 or to p,p'-DDE. However, pooled adjusted odds ratios (ORs) for high conduct problem scores with a doubling of exposure were 1.19 (95% CI: 0.99, 1.42) and 1.16 (95% CI: 0.96, 1.41) for pre- and postnatal PCB-153, respectively, and 1.25 (95% CI: 1.04, 1.51) and 1.24 (95% CI: 1.01, 1.51) for pre- and postnatal p,p'-DDE, respectively. Corresponding ORs for high hyperactivity scores were 1.24 (95% CI: 0.94, 1.62) and 1.08 (95% CI: 0.81, 1.45) for pre- and postnatal PCB-153, respectively, and 1.43 (95% CI: 1.06, 1.92) and 1.27 (95% CI: 0.93, 1.73) for pre- and postnatal p,p'-DDE, respectively. CONCLUSION: Prenatal and early postnatal exposures to p,p'-DDE and PCB-153 were associated with a higher prevalence of abnormal scores for conduct and hyperactivity at 5­9 y of age in our study population. These findings provide further support for the importance of minimizing organochlorine exposures to young children and to women of childbearing age. https://doi.org/10.1289/EHP553.

Prenatal smoking exposure, measured as maternal serum cotinine, and children's motor developmental milestones and motor function: A follow-up study.

BACKGROUND: Cohort studies have indicated an association between prenatal smoking exposure and children's motor difficulties. However, results are inconsistent and exposure is most often self-reported. Studies indicate that measurement of serum cotinine can result in a more accurate status of smoking exposure in comparison with self-report. OBJECTIVES: To investigate whether prenatal smoking exposure, measured as maternal serum cotinine, is associated with maternal interview based assessment of motor development in infancy (age at crawling, standing-up and walking) and motor skills at young school age (assessed by the Developmental Coordination Disorder Questionnaire 2007 (DCDQ'07)). METHOD: In 2002-2004, 1,253 pregnant women from Greenland and Ukraine were included in the INUENDO birth cohort. The participating women filled in questionnaires and 1,177 provided blood samples, which were analyzed for serum cotinine. Smokers were defined as women with a serum cotinine concentration >10ng/ml. At follow-up when the offspring were 6-9 years of age 1,026 of the parents from the cohort participated. They completed an interview-based questionnaire including questions about age at motor milestones of their children. In addition, child motor development was assessed using the questionnaire "DCDQ'07". Linear regression analyzes were performed and adjusted for covariates; age of the mother and child, parity, sex, maternal educational level, maternal pre-pregnancy alcohol consumption and duration of breastfeeding. Data were stratified by country. RESULTS: No statistically significant difference in age at motor milestones was found comparing children of smokers with children of non-smokers. Also, there was no statistically significant difference in motor score (Developmental Coordination Disorder Questionnaire Score, DCDQ-score) among five to seven-year-old children. However, in Greenland children of smokers had a lower DCDQ-score than children of non-smokers at eight to nine years (-2.2 DCDQ points, 95% CI: -4.3;-0.1). Supplementary results for the same age group in Greenland showed that children of smokers had higher odds of being classified with motor difficulties in comparison with children of non-smokers (OR=1.9, 95% CI: 1.1;3.3). CONCLUSION: Maternal serum cotinine was not related to delayed motor development milestones or reduced motor function abilities in children up to 7 years of age. Reduced motor skills observed in 8-9 years old exposed children warrant further study.

Tobacco smoking during pregnancy and risk of adverse behaviour in offspring: A follow-up study.

OBJECTIVES: This study examines associations between prenatal exposure to tobacco smoking and adverse behaviour in the offspring. METHODS: We included 1016 pregnant women from Greenland and Ukraine (526 from Greenland and 490 from Ukraine). Serum cotinine measurements were used to identify smoking pregnant women. When the children were from five to nine years of age, the parents assessed the child's behaviour using the Strength and Difficulties Questionnaire (SDQ). RESULTS: Overall, smoking in pregnancy was not associated with a higher probability of adverse behaviour assessed by the total SDQ score. However, in the crude analysis smoking was associated with a higher mean difference of SDQ-total score. In Greenland the SDQ-total mean difference (MD) was (MD (95% CI)=1.31 points (0.42; 2.19)) and in Ukraine (MD (95% CI)=0.18 points (-1.2; 0.91)), whereas the adjusted mean differences were statistically non-significant. CONCLUSIONS: In utero exposure to tobacco smoking was not associated with a significant higher risk of adverse behaviour in the offspring, but elevated risk of adverse behaviour among children prenatally exposed to smoking cannot be excluded.

Food intake and serum persistent organic pollutants in the Greenlandic pregnant women: The ACCEPT sub-study.

The Greenlandic Inuit have high blood concentrations of environmental persistent organic pollutants (POPs). High POP concentrations have been associated with age, smoking and consumption of marine mammals. Studies have indicated that exposure to POPs during pregnancy may adversely affect fetal and child development. To assess geographical differences in diet, lifestyle and environmental contaminant exposure among pregnant women in Greenland, blood samples and questionnaire data were collected from 207 pregnant women in five Greenlandic regions (North, Disco Bay, West, South and East). Blood samples were analyzed for 11 organochlorine pesticides (OCPs), 14 polychlorinated biphenyls (PCBs), 5 polybrominated diphenyl ethers (PBDEs), 15 perfluoroalkylated substances (PFASs) and 63 metals. A trend of higher intake of marine mammals in the East and North regions was reflected by a higher n-3/n-6 fatty acid ratio. Participants in the East region tended also to have higher intake of terrestrial species. A significant higher seabird intake was seen for pregnant women in the West region. Significant regional differences were found for blood concentrations of PCBs, OCPs, PFASs and mercury, with higher levels in the North and East regions. PFASs were significantly associated with PCBs and OCPs in most of the regions. In the North region, PFASs were associated with both selenium and mercury. No significant regional difference was observed for PBDEs. The regional differences of blood levels of POPs and mercury were related to differences in intake of the traditional food. Compared to earlier reports, decreased levels of legacy POPs, Hg and Pb and perfluorooctane sulfonate and perfluorooctanoic acid were observed, but the levels of PFAS congeners perfluorohexane sulfonate and perfluorononanoic acid were sustained. The detection of POPs and heavy metals in maternal blood indicates fetal exposure to these compounds possibly influencing fetal development.

Motor development following in utero exposure to organochlorines: a follow-up study of children aged 5-9 years in Greenland, Ukraine and Poland.

BACKGROUND: Prior studies on the association between prenatal exposure to polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (DDE) and child motor development have found contradicting results. Using data collected in the INUENDO cohort in Kharkiv (Ukraine), Warsaw (Poland) and Greenland (N = 1,103) between the years 2002 and 2012, we examined relations of prenatal exposure to 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE) and 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) on motor development and developmental milestones; crawling, standing-up and walking. METHODS: CB-153 and p,p'-DDE were measured in maternal blood in second or third trimester of pregnancy. Motor development was measured in terms of the parentally assessed screening tool Developmental Coordination Disorder Questionnaire 2007 and developmental milestones were assessed via retrospective parental reports of child age at the first time of crawling, standing-up and walking. RESULTS: We saw no associations between tertiles of CB-153 and p,p'-DDE or log-transformed exposures and retrospective reports of the developmental milestones crawling, standing-up and walking in infancy or the motor skills measured as developmental coordination disorder at young school age. CONCLUSIONS: In utero exposure to CB-153 and p,p'-DDE was not associated with parentally retrospectively assessed developmental milestones in infancy or parentally assessed motor skills at young school age. The use of a more sensitive outcome measure may be warranted if subtle effects should be identified.

Anthropometry in 5- to 9-Year-Old Greenlandic and Ukrainian Children in Relation to Prenatal Exposure to Perfluorinated Alkyl Substances.

BACKGROUND: In some animal studies, perfluorinated alkyl substances are suggested to induce weight gain. Human epidemiological studies investigating these associations are sparse. OBJECTIVE: We examined pregnancy serum concentrations of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) and the prevalence of offspring overweight (> 1 SD) and waist-to-height ratio (WHtR) > 0.5 at 5-9 years of age. METHODS: Sera from 1,022 pregnant women enrolled in the INUENDO cohort (2002-2004) from Greenland and Kharkiv (Ukraine) were analyzed for PFOA and PFOS using liquid chromatography-tandem mass spectrometry. Relative risks (RR) of being overweight and having WHtR > 0.5 in relation to continuous and categorized (tertiles) PFOA and PFOS were calculated at follow-up (2010-2012) using generalized linear models. RESULTS: Pooled PFOA median (range) was 1.3 (0.2-5.1) and PFOS median (range) was 10.8 (0.8-73.0) ng/mL. For each natural logarithm-unit (ln-unit) increase of pregnancy PFOA, the adjusted RR of offspring overweight was 1.11 [95% confidence interval (CI): 0.82, 1.53] in Greenlandic children. In Ukrainian children, the adjusted RR of offspring overweight was 1.02 (95% CI: 0.72, 1.44) for each ln-unit increase of pregnancy PFOA. Prenatal exposure to PFOS was not associated with overweight in country-specific or pooled analysis. The adjusted RR of having WHtR > 0.5 for each ln-unit increase of prenatal exposure to PFOA was 1.30 (95% CI: 0.97, 1.74) in the pooled analysis. For 1-ln-unit increase of prenatal exposure to PFOS, the adjusted RR of having a WHtR > 0.5 was 1.38 (95% CI: 1.05, 1.82) in the pooled analysis. CONCLUSIONS: The results indicate that prenatal PFOA and PFOS exposures may be associated with child waist-to-height ratio > 0.5. Prenatal PFOA and PFOS exposures were not associated with overweight.

Pregnancy serum concentrations of perfluorinated alkyl substances and offspring behaviour and motor development at age 5-9 years--a prospective study.

BACKGROUND: In animal studies, perfluorinated alkyl substances affect growth and neuro-behavioural outcomes. Human epidemiological studies are sparse. The aim was to investigate the association between pregnancy serum concentrations of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) and offspring behaviour and motor development at 5-9 years of age. METHODS: Maternal sera from the INUENDO cohort (2002-2004) comprising 1,106 mother-child pairs from Greenland, Kharkiv (Ukraine) and Warsaw (Poland) were analysed for PFOS and PFOA, using liquid-chromatography-tandem-mass-spectrometry. Exposures were grouped into country specific as well as pooled tertiles as well as being used as continuous variables for statistical analyses. Child motor development and behaviour at follow-up (2010-2012) were measured by the Developmental Coordination Disorder Questionnaire 2007 (DCDQ) and Strength and Difficulties Questionnaire (SDQ), respectively. Exposure-outcome associations were analysed by multiple logistic and linear regression analyses. RESULTS: In the pooled analysis, odds ratio (OR) (95% confidence interval (CI)) for hyperactivity was 3.1 (1.3, 7.2) comparing children prenatally exposed to the highest PFOA tertile with those exposed to the lowest PFOA tertile. Comparing children in the highest PFOS tertile with those in the lowest PFOS tertile showed elevated but statistically non-significant OR of hyperactivity (OR (95% CI) 1.7 (0.9, 3.2)). In Greenland, elevated PFOS was associated with higher SDQ-total scores indicating more behavioural problems (ß (95% CI)=1.0 (0.1, 2.0)) and elevated PFOA was associated with higher hyperactivity sub-scale scores indicating more hyperactive behaviour (ß (95% CI)=0.5 (0.1, 0.9)). Prenatal PFOS and PFOA exposures were not associated with motor difficulties. CONCLUSIONS: Prenatal exposure to PFOS and PFOA may have a small to moderate effect on children's neuro-behavioural development, specifically in terms of hyperactive behaviour. The associations were strongest in Greenland where exposure contrast is largest.

Population surveys in Greenland 1993-2009: temporal trend of PCBs and pesticides in the general Inuit population by age and urbanisation.

The purpose of the study was to analyse temporal trends (1993-2009) of the concentrations of organochlorine contaminants (14 congeners of polychlorinated biphenyls (PCB) and 11 pesticides) in the blood of Greenland Inuit according to age and urbanisation. Statistical determinants for the contaminant concentrations included (for PCB congener 153) age (Δr(2)=0.35), marine diet (Δr(2)=0.10), smoking (Δr(2)=0.02), and sex (Δr(2)=0.01) with comparable results for other organochlorine contaminants. After adjustment for age, diet, smoking, and sex a significant decreasing trend was present for all contaminants ranging from 41% for mirex to 56% for hexachlorobenzene. The temporal trend was most pronounced among participants below the age of 65 years. The decrease started later in villages than in towns. The decrease was present in all age groups and in the capital, other towns, and villages. The decrease is probably due to a combination of reduced concentrations of the contaminants in the wildlife and a slight temporal reduction in the consumption of marine mammals. The significant downwards trend of legacy POPs shows that the legislation works but it must be kept in mind that according to the cumulated scientific evidence there are a multitude of non-regulated persistent organic contaminants in the diet as well as high levels of methylmercury.

Fertility and markers of male reproductive function in Inuit and European populations spanning large contrasts in blood levels of persistent organochlorines.

OBJECTIVE: We synthesized the main findings from an international epidemiologic study on the impact of biopersistent organic pollutants (POPs) on human reproductive function. DATA SOURCES AND EXTRACTION: We used a database with interview and biological data from 2,269 women and their spouses, and 18 published core papers. DATA SYNTHESIS: The study did not provide direct evidence of hormone-like activity of the polychlorinated biphenyl (PCB) congener CB-153 and the main dichlorodiphenyltrichloroethane (DDT) metabolite, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE), as serum concentrations of these compounds were not consistently related to either endogenous or exogenous hormone activity in serum. Nevertheless several links bewteen POP exposure and biomarkers of male reproductive function were identified. First, an association between high CB-153 serum levels and low sperm counts was detected within a subgroup of men with short androgen receptor CAG repeat length. Second, a relationship between increased CB-153 serum concentrations and decreased sperm motility was seen in all four studied regions, and indications of reduced neutral alpha-glucosidase activity in seminal plasma point to a post-testicular effect. Third, damage of sperm chromatin integrity was considerably less frequent in Greenlandic Inuits compared with that in European groups, and only in the latter was impairment of sperm chromatin integrity related to POPs. Despite these effects, fertility in terms of time taken to conceive was not related to POPs except in Inuits. A likely explanation of the latter was not identified. CONCLUSIONS: POPs may interfere with male reproductive function without major impact on fertility. The data do not provide direct evidence for endocrine disruption, hence other mechanisms should also be considered.

Polymorphisms in genes regulating androgen activity among prostate cancer low-risk Inuit men and high-risk Scandinavians.

In Greenland, with a male population of approximately 30 000 individuals, the incidence of prostate cancer is extremely low with only three cases described during the period 1988-1997. Polymorphisms related to high androgen metabolism and/or response in the 5alpha-reductase type 2 (SRD5A2) and the androgen receptor (AR) genes, respectively, have been linked to prostate cancer. Our objective was to analyse whether the distribution of these polymorphisms differed between the prostate cancer low-risk population from Greenland and the relatively high-risk Swedish male population. The SRD5A2 polymorphisms A49T, V89L and R227Q, and the CAG and GGN repeats in the AR gene were genotyped in leucocyte DNA from 196 Greenlanders and 305 Swedish military conscripts. All subjects had the wild-type R/R genotype of the R227Q marker. The high-activity variants A49T A/T and V89L V/V occurred less frequently (2% vs. 5%, p = 0.048 and 33% vs. 46%, p = 0.0027) in Greenland compared with Sweden, whereas the low-activity L/L genotype was more frequent in Greenland (24% vs. 13%, p = 0.0024). Greenlanders also had longer AR CAG repeats than the Swedish population (median 24 vs 22, p < 0.0005). Greenlanders also had a higher frequency of the GGN = 23 allele (85% vs. 54%, p < 0.0001). Our results suggest that Greenlanders are genetically predisposed to a lower activity in testosterone to 5alpha-dihydrotestosterone turnover and to lower AR activity, which, at least partly, could explain their low incidence of prostate cancer.

Traditional and modern Greenlandic food - dietary composition, nutrients and contaminants.

OBJECTIVES: High levels of n-3 fatty acids and other nutrients in traditional Inuit food appear to provide some protection against the typical diseases of affluent industrialized societies: cardiovascular diseases and type 2 diabetes. An increased intake of imported food among Inuits will probably increase their frequency of these diseases. However, since the 1970s it has become evident that the marine-based Inuit diet also contains high levels of potentially toxic lipophilic organic pollutants and heavy metals. Since these two food related opposing health effects appear to be inseparable, the phenomenon has been known as "The Arctic Dilemma". However, both the fatty acid composition and the contaminant levels vary in Greenlandic food items. Thus in principle it is possible to compose a diet where the benefits and risks are better balanced. Our objectives of this study were to compare traditional and modern meals in Greenland concerning the dietary composition, nutrients, and health indicators among the consumers. STUDY DESIGN: The present study was a cross-sectional dietary survey as part of the Arctic Monitoring and Assessment, Human Health Programme (AMAP). These results were compared with older dietary surveys in Greenland. METHODS: Dietary components, fatty acids, and nutrients in 90 local meals collected by duplicate portion method in Uummannaq town, north Greenland 2004 and in Narsaq, south Greenland 2006, were compared with 177 duplicate meals sampled in the village of Igdslorsuit, Uummannaq, district, 1976 and also compared with other dietary studies in Greenland 1953-1987. Anthropometric measures (weight, height, and body mass index, BMI) and blood lipids were measured as health indicators among the participants. RESULTS: Between the traditional foods sampled or analysed 30-50 years ago and the modern food from 2004 to 2006, significant differences were found in the dietary composition. The percentage of local food had decreased, to a present average of about 20% and with it the dietary content of n-3 fatty acids. Also, the intakes of many vitamins and minerals had decreased, and were below Nordic Nutrient Recommendations in 2004 and 2006. Vitamin A, B(1), (B(2)), B(12), iron, iodine, phosphorus, and selenium contents were correlated with n-3 content, whereas vitamin C, folate, and calcium contents were not and the same time very low. In the traditional food, especially from the villages, the intakes of vitamin A, vitamin D, and iron were extremely high and borderline toxic. The levels of contaminants such as organochlorins and heavy metals were also strongly correlated with the relative content of local food in the diet. The best balance between potentially beneficial and harmful substances was found for 20-30% local food, corresponding to a daily intake of 3-5 g of n-3 fatty acids. Body weight, height, body mass index (BMI), cholesterol, and S-triglycerides had increased significantly between 1976 and 2004. CONCLUSION: The dietary changes to a more western fare were found to be negative resulting in less adequate nutrient coverage but at the same time lower contaminant load. Thus, we recommend not to increase the consumption of local products beyond the present level but rather to improve the quality of the imported food.

Human accumulation of mercury in Greenland.

In the Arctic, the traditional diet exposes its people to a high intake of mercury especially from marine mammals. To determine whether the mercury is accumulated in humans, we analyzed autopsy samples of liver, kidney and spleen from adult ethnic Greenlanders who died between 1990 and 1994 from a wide range of causes, natural and violent. Liver, kidney and spleen samples from between 33 and 71 case subjects were analyzed for total mercury and methylmercury, and liver samples also for selenium. Metal levels in men and women did not differ and were not related to age except in one case, i.e. for total mercury in liver, where a significant declining concentration with age was observed. The highest total mercury levels were found in kidney followed by liver and spleen. Methylmercury followed the same pattern, but levels were much lower, constituting only 19% of the total mercury concentration in liver and spleen and as little as 3% in kidney. In liver selenium was found in surplus to mercury on a molar basis. Mercury concentrations in the liver and kidneys of Greenlanders were elevated compared to levels in the general population in Japan, Korea and several European countries, except in the Faroe Islands where mercury levels were 2-3 times higher. This is in accordance with the expected exposure of mercury in the diet.

Contaminants, diet, plasma fatty acids and smoking in Greenland 1999-2005.

OBJECTIVES: The purpose of this study is to monitor and assess human exposure to pollution in the Arctic which presents a potential future health risk for the local populations. Epidemiological studies in Greenland have shown that human blood levels of several organic contaminants are very high, especially in the North where people depend on local food. In East Greenland (Ittoqqortoormiit (Scoresbysund)) the population shows the highest blood levels of several persistent organic pollutants found in Arctic countries, especially PCB, the levels of which exceed Canadian guideline levels. As in other Arctic countries, the predominant source of these contaminants is the local diet. However, other factors such as smoking may influence the metabolism and thereby the accumulation of toxic substances. STUDY DESIGN: This project is part of the human health program of the ongoing circumpolar "Artic Monitoring and Assessment Programme". Lifestyle, anthropometric factors, and dietary survey results covering 500 men and women from 6 Greenlandic districts were analyzed along with other factors blood lipids, fatty acid profiles, heavy metals and concentrations of persistent organic pollutants (POPs). RESULTS: The dietary survey showed that the traditional food on the average provided 20-30% of the total energy intake. However, the relative monthly meal intake of seal, whale, polar bear, fish and game, and the composition of imported food, varied between districts. Seal and polar bear intake, and, in particular all the plasma n-3 fatty acids, were significantly correlated with organic contaminant concentrations, (betaHCH, chlordanes, DDTs, Hexachlorobenzene, Mirex, PCBs, and toxaphenes) p<0.01(). After adjusting for age, district, dietary factors or plasma n-3 fatty acids, smoking was significantly correlated with high levels of all the above mentioned POPs. CONCLUSION: The main predictors of high contaminant levels in Greenland were age, district, male gender, smoking and high plasma n-3/n-6 ratio as a marker of high dietary intake of local marine mammals.

Accumulation of cadmium in livers and kidneys in Greenlanders.

In the Arctic, the traditional diet exposes its people to a very high intake of cadmium because it is highly concentrated in the liver and kidneys of commonly eaten marine mammals. In one study in Greenland, the cadmium intake was estimated to 182 microg/day/person in the fall and 346 in the spring. To determine whether the cadmium is accumulated in humans, we analyzed autopsy samples of liver and kidneys from 95 ethnic Greenlanders (aged 19-89) who died from a wide range of causes. The cadmium concentration in liver (overall mean 1.97 microg/g wet wt) appeared to be unrelated to any particular age group, whereas the concentrations in the kidneys peaked in Greenlanders between 40 and 50 years of age (peak concentration 22.3 microg/g wet wt). Despite the high cadmium levels in the typical Greenlander diet, we found that the cadmium concentrations in livers and kidneys were comparable to those reported from Denmark, Sweden, Australia and Great Britain. Furthermore, even though the mean cadmium intake from the diet was estimated to be 13-25 times higher in Greenlanders than in Danes, we found similar cadmium levels in the kidneys of both. Seal livers and kidneys are the main source of cadmium in the diet of Greenlanders, but these tissues are not eaten in Denmark. Thus, our results suggest that the accumulation of cadmium from Greenlander's marine diet is very low.

Dietary composition and contaminants in north Greenland, in the 1970s and 2004.

OBJECTIVES: The fatty acid composition and other nutrients in traditional Inuit food appear to provide some protection against diseases of affluent industrialized societies, such as cardiovascular diseases and type 2 diabetes. A transition towards increased amounts of imported food might increase the occurrence of these diseases among Inuit. However, since the 1970s it has become evident that the marine-based Inuit diet also contains high levels of potentially toxic lipophilic organic pollutants and heavy metals. Since these two opposing effects on health appear to be inseparable, the phenomenon has become known as "The Arctic Dilemma". However, both the fatty acid composition and the contaminant levels vary in Greenlandic food items. Thus, in theory, it is possible to compose a diet where the benefits outweigh the risks. Our objective was to compare traditional and modern meals in Greenland regarding dietary composition, content of n-3 fatty acids and contaminants. STUDY DESIGN: The present study was part of the Arctic Monitoring and Assessment Programme, AMAP, comparing the results of dietary composition and nutrients in 177 traditional meals collected in Uummannaq municipality, north Greenland in 1976 with 90 meals sampled in Uummannaq town in 2004 under similar conditions. Eleven pesticides, 14 PCB congeners, heavy metals, selenium, and fatty acids were analysed in meals and blood samples from the participants. Contaminant levels were compared between 1976 and 2004 after adjustment for n-3 fatty acids, indicating local food content. RESULTS: Between the traditional meals collected 30 years ago and the meals from 2004, dramatic and significant changes have occurred in the dietary composition. The percentage of local food has decreased, and with it the intake of n-3 fatty acids. Calculated as daily intake, all but three contaminants had decreased significantly. However, this could be explained by the lower intake of local food. After adjustment for n-3 fatty acid content in the food, significant declines of concentration in the local food were evident only for PCBs and lead, whereas for mercury, DDTs, and chlordanes the levels were unchanged, and for hexachlorobenzene, mirex, and toxaphenes, the levels had increased significantly. CONCLUSION: The consumption of locally produced food has decreased in Greenland during the last 30 years and this has led to a reduction in the daily intake of contaminants. However, the concentrations of contaminants in local food items have not decreased, except for PCB and Lead. Therefore, we recommend that the consumption of local products is not increased beyond the present level, until the level of contaminants is reduced to a safer level.

Lead shot from hunting as a source of lead in human blood.

This study investigates the relationship between the intake of birds hunted with lead shot and the lead concentration in human blood. Fifty adult men from Nuuk, Greenland took part in the study. From September 2003 to June 2004 they regularly gave blood samples and recorded how many birds they ate. We found a clear relationship between the number of bird meals and blood lead and also a clear seasonal variation. The concentration was highest in mid-winter when bird consumption is at its highest. Blood lead was low (15 microg/L, mean concentration) among the participants reporting not eating birds. Among those reporting to eat birds regularly, blood lead was significantly higher, up to 128 microg/L (mean concentration). Concentrations depended on the frequency of bird meals: the more the bird meals, the higher the resulting blood lead. This clear relationship points to lead shot as the dominating lead source to people in Greenland.