Micro-distribution of arsenic in toenail clippings using laser ablation inductively coupled plasma mass spectrometry: implications for biomonitoring.

Toenails are a common monitoring tool for arsenic exposure, but the risk of external contamination of toenails has cast doubt on its usefulness. The main objective of this study is to investigate the micro-distribution of arsenic through the dorsoventral plane of nail clippings to understand endogenous vs exogenous sources. We used laser-ablation inductively coupled plasma mass spectrometry to measure arsenic through a dorsoventral cross-section of the nail plate collected from reference (N = 17) and exposed individuals (N = 35). Our main results showed (1) bulk toenail concentrations measured using ICP-MS in this study ranged from 0.54 to 4.35 µg/g; (2) there was a double-hump pattern in arsenic concentrations, i.e., dorsal and ventral layers had higher arsenic than the inner layer; (3) the double-hump was more pronounced in the exposed group (ventral: 6.25 µg/g; inner: 0.75 µg/g; dorsal: 0.95 µg/g) than the reference group (ventral: 0.58 µg/g; inner: 0.15 µg/g; dorsal: 0.29 µg/g) on average; (4) the distribution was, in part, associated with different binding affinity of nail layers (i.e., ventral > dorsal > inner); (5) most individuals in the higher exposure group showed > 25% contamination in ventral and dorsal nail layers; and (6) there were no statistically significant correlations between LA-ICP-MS arsenic with either bulk toenail arsenic or urine arsenic from the same individuals. Our results on micro-distribution and binding affinity provide insight into the impact of external contamination on arsenic concentrations and show how LA-ICP-MS can access the protected inner nail layer to provide a more accurate result.

The prevalence of food insecurity is high and the diet quality poor in Inuit communities.

Indigenous peoples experience a disproportionate burden of food insecurity and the Arctic is no exception. We therefore evaluated the prevalence, socio-demographic, and dietary correlates of food insecurity in the most comprehensive assessment of food insecurity in Arctic Canada. A cross-sectional survey of 1901 Inuit households was conducted in 2007-2008. Measurements included food insecurity, 24-h dietary recalls, socio-demographics, and anthropometry. Food insecurity was identified in 62.6% of households (95% CI = 60.3-64.9%) with 27.2% (95% CI = 25.1-29.3%) of households severely food insecure. The percent with an elevated BMI, waist circumference, and percent body fat was lower among individuals from food insecure households compared to food secure households (P ≤ 0.001). Adults from food insecure households had a significantly lower Healthy Eating Index score and consumed fewer vegetables and fruit, grains, and dairy products, and consumed a greater percent of energy from high-sugar foods than adults from food secure households (P ≤ 0.05). Food insecurity was associated with household crowding, income support, public housing, single adult households, and having a home in need of major repairs (P ≤ 0.05). The prevalence of having an active hunter in the home was lower in food insecure compared to food secure households (P ≤ 0.05). Food insecurity prevalence is high in Inuit communities, with implications for diet quality that over the long-term would be anticipated to exacerbate the risk of diet-related chronic diseases. Actions are required to improve food security that incorporate the traditional food system and healthy market food choices.

Cohort profile: health effects monitoring programme in Ndilǫ, Dettah and Yellowknife (YKHEMP).

PURPOSE: The Yellowknife Health Effects Monitoring Programme (YKHEMP) was established to examine the relationship of exposure to arsenic and other chemicals of potential concern such as antimony, cadmium, lead, manganese and vanadium and health outcomes. PARTICIPANTS: A total of 2037 individuals were recruited, including children (age 3-19) and adults (age 20+), residing in Dettah, NdilÇ« and Yellowknife, in the Northwest Territories, Canada, in two waves in Fall 2017 and Spring 2018. In Yellowknife, there were 891 (675 adults, 216 children), randomly selected participants with a participation rate of 64%. In addition, we also recruited a total of 875 (669 adults, 206 children) volunteer participants. A total of 225 (137 adults, 88 children) of the Yellowknives Dene First Nation (YKDFN), and 46 (33 adults, 13 children) of the North Slave Métis Alliance participated in the study. Each participant answered a lifestyle questionnaire as well as provided toenail clippings and urine for contaminant testing and saliva samples for testing of genetic polymorphisms associated with arsenic metabolism. Participants also provided consent to have their medical records reviewed by the research team for the past 5 years to allow for the investigation between exposure and health outcomes. FINDINGS TO DATE: The adult YKHEMP participants had lower urinary total arsenic but the children had higher inorganic arsenic than the general Canadian population. There was no difference in urinary total arsenic concentrations between adults and children, however, urinary inorganic arsenic concentrations were generally higher in children than in adults in all four YKHEMP sampling groups. The adult YKDFN participants had lower urinary total arsenic and inorganic arsenic concentrations compared with the random selected and volunteer participants. FUTURE PLANS: YKHEMP is designed as a prospective cohort study; the children participants will be re-examined in 2022 and both adult and children participants in 2027.

Health risk assessment of arsenic exposure among the residents in Ndilǫ, Dettah, and Yellowknife, Northwest Territories, Canada.

There are concerns in Yellowknife, Northwest Territories, Canada, about arsenic exposure due to past mining operations, particularly the former Giant Mine. The objective of this study was to characterize the risk of arsenic exposure and associated risk factors among the local residents. Arsenic (As) and its species were quantified in urine (n = 1966) using inductively coupled mass spectrometry. Children in the study were found to have significantly higher (p < 0.05) urinary inorganic-related As (uiAs) concentrations than children in the general Canadian population, as well as adults in the study. Additionally, uiAs concentrations in children, particularly those above the 95th percentile, are above the Biomonitoring Equivalents (BE) levels that are associated with dermal effects, vascular problems and cancer risks. Multiple linear regression results showed that market seafood (fish and shellfish) and rice consumption frequency were significantly positively associated with uiAs. Specific to children, drinking lake water was positively associated with uiAs. Specific to adults, consumption of local mushrooms and berries were significantly positively associated with uiAs while there was a significant negative association with age, smoking and recreational water activities. The risk factors identified in this research can be used for public health education to lower arsenic intake. Overall, these results support the need for an ongoing monitoring program.

Impacts of decline harvest of country food on nutrient intake among Inuit in Arctic Canada: impact of climate change and possible adaptation plan.

BACKGROUND: The pervasive food insecurity and the diet transition away from local, nutrient-rich country foods present a public health challenge among Inuit living in the Canadian Arctic. While environmental factors such as climate change decreased the accessibility and availability of many country food species, new species were introduced into regions where they were previously unavailable. An adaptation such as turning to alternate country food species can be a viable solution to substitute for the nutrients provided by the declined food species. The objective of this study was to estimate the impact on nutrient intake using hypothetical scenarios that current commonly harvested country foods were reduced by 50%, and were replaced with alternate or new species. METHODS: Data collected during the 2007-2008 Inuit Health Survey from 36 Canadian Arctic communities spanning Nunavut, the Inuvialuit Settlement Region and Nunatsiavut were used. RESULTS: A 50% decline in consumption of fish, whale, ringed seals and birds (the food that was reported to be in decline) resulted in a significant decrease in essential nutrient intake. Possible substitute foods were identified but some nutrients such as zinc and especially vitamin D were most often found lacking in the alternative diet. CONCLUSIONS: If the alternative species are not available or feasible, more expensive and less nutritionally dense store-bought foods may be sought. Given the superior quality of country foods and their association with food security, and Inuit cultural health and personal identity, developing skills and awareness for adaptation, promoting regional sharing networks, forming a co-management agency and continuing nutritional monitoring may potentially preserve the nutritional integrity of Inuit diet, and in turn their health and cultural survival.

Prevalence of affirmative responses to questions of food insecurity: International Polar Year Inuit Health Survey, 2007-2008.

OBJECTIVES: Assess the prevalence of food insecurity by region among Inuit households in the Canadian Arctic. STUDY DESIGN: A community-participatory, cross-sectional Inuit health survey conducted through face-to-face interviews. METHODS: A quantitative household food security questionnaire was conducted with a random sample of 2,595 self-identified Inuit adults aged 18 years and older, from 36 communities located in 3 jurisdictions (Inuvialuit Settlement Region; Nunavut; Nunatsiavut Region) during the period from 2007 to 2008. Weighted prevalence of levels of adult and household food insecurity was calculated. RESULTS: Differences in the prevalence of household food insecurity were noted by region, with Nunavut having the highest prevalence of food insecurity (68.8%), significantly higher than that observed in Inuvialuit Settlement Region (43.3%) and Nunatsiavut Region (45.7%) (p≤0.01). Adults living in households rated as severely food insecure reported times in the past year when they or other adults in the household had skipped meals (88.6%), gone hungry (76.9%) or not eaten for a whole day (58.2%). Adults living in households rated as moderately food insecure reported times in the past year when they worried that food would run out (86.5%) and when the food did not last and there was no money to buy more (87.8%). CONCLUSIONS: A high level of food insecurity was reported among Inuit adults residing in the Canadian Arctic, particularly for Nunavut. Immediate action and meaningful interventions are needed to mitigate the negative health impacts of food insecurity and ensure a healthy Inuit population.