Assessing determinants of maternal blood concentrations for persistent organic pollutants and metals in the eastern and western Canadian Arctic

Abstract

Aboriginal peoples in the Canadian Arctic are exposed to persistent organic pollutants (POPs) and metals mainly through their consumption of a traditional diet of wildlife items. Recent studies indicate that many human chemical levels have decreased in the north, likely due to a combination of reduced global chemical emissions, dietary shifts, and risk mitigation efforts by local health authorities. Body burdens for chemicals in mothers can be further offset by breastfeeding, parity, and other maternal characteristics. We have assessed the impact of several dietary and maternal covariates following a decade of awareness of the contaminant issue in northern Canada, by performing multiple stepwise linear regression analyses from blood concentrations and demographic variables for 176 mothers recruited from Nunavut and the Northwest Territories during the period 2005-2007. A significant aboriginal group effect was observed for the modeled chemicals, except for lead and cadmium, after adjusting for covariates. Further, blood concentrations for POPs and metals were significantly associated with at least one covariate of older age, fewer months spent breastfeeding, more frequent eating of traditional foods, or smoking during pregnancy. Cadmium had the highest explained variance (72.5%) from just two significant covariates (current smoking status and parity). Although Inuit participants from the Northwest Territories consumed more traditional foods in general, Inuit participants from coastal communities in Nunavut continued to demonstrate higher adjusted blood concentrations for POPs and metals examined here. While this is due in part to a higher prevalence of marine mammals in the eastern Arctic diet, it is possible that other aboriginal group effects unrelated to diet may also contribute to elevated chemical body burdens in Canadian Arctic populations.

Biomonitoring of Lead, Cadmium, Total Mercury, and Methylmercury Levels in Maternal Blood and in Umbilical Cord Blood at Birth in South Korea

“…As an example with high seafood consumption country like Korea, Sakamoto et al has reported that the mean maternal RBCs level of lead and mercury were 26.4 ng/g and 9.41 ng/g from Japanese women [ 23 ]. Additionally, high levels of mercury and methylmercury in pregnant women and children were also observed in studies from the Mediterranean [ 24 ] and Arctic region [ 25 ].…”

Variations in serum concentrations of selected organochlorines among delivering women in Argentina. The EMASAR study

“…Geographic differences in OC levels as observed likely also reect history, socioeconomic, culture, physiological factors, lifestyle and dietary differences. 22,24,[41][42][43] Age as a positive predictor of serum OC concentrations and parity and previous breastfeeding as negative ones are well understood. 35,44 Because of the relatively long half-lives (in years) of OCs (typically > 7 years), 45 body burdens increase over time.…”

A State‐of‐the‐Art Review of Indigenous Peoples and Environmental Pollution

“…While the number of studies examining the impacts of environmental pollution upon IPs is growing (Brugge and Gobble 2002; Curren et al 2015), most of this research is isolated and fragmented across disciplines and geographic regions. Few efforts have cut across disciplinary topics or regions (e.g., pollution in Arctic traditional foods [Kuhnlein and Chan 2000]; water, sanitation, and IPs [Jiménez et al 2014]), and there is no global review that maps out the worldwide impacts of environmental pollution on IPs.…”