Pregnant Inuit Women’s Exposure to Metals and Association with Fetal Growth Outcomes: ACCEPT 2010–2015

Abstract

Environmental contaminants such as heavy metals are transported to the Arctic regions via atmospheric and ocean currents and enter the Arctic food web. Exposure is an important risk factor for health and can lead to increased risk of a variety of diseases. This study investigated the association between pregnant women’s levels of heavy and essential metals and the birth outcomes of the newborn child. This cross-sectional study is part of the ACCEPT birth cohort (Adaption to Climate Change, Environmental Pollution, and dietary Transition) and included 509 pregnant Inuit women ≥18 years of age. Data were collected in five Greenlandic regions during 2010–2015. Population characteristics and birth outcomes were obtained from medical records and midwives, respectively, and blood samples were analyzed for 13 metals. Statistical analysis included one-way ANOVA, Spearman’s rho, and multiple linear and logistic regression analyses. The proportion of current smokers was 35.8%. The levels of cadmium, chromium, and nickel were higher compared to reported normal ranges. Significant regional differences were observed for several metals, smoking, and parity. Cadmium and copper were significantly inversely related to birth outcomes. Heavy metals in maternal blood can adversely influence fetal development and growth in a dose–response relationship. Diet and lifestyle factors are important sources of toxic heavy metals and deviant levels of essential metals. The high frequency of smokers in early pregnancy is of concern, and prenatal exposure to heavy metals and other environmental contaminants in the Greenlandic Inuit needs further research.

Time Trend of Persistent Organic Pollutants and Metals in Greenlandic Inuit during 1994–2015

“…This is in accordance to the main source of Hg in the Arctic population of marine mammals [ 74 ], and the Hg concentrations in the Arctic marine mammal have decreased over the years [ 75 , 76 ]. Although declining, it should be kept in mind that Hg levels in Greenlanders are still higher than other Arctic populations, such as Alaska, Norway, Iceland, Finland and Russia [ 53 , 68 , 77 ].…”

“…The subjects and sampling methods were described in detail elsewhere [ 16 , 18 , 19 , 49 , 50 , 53 , 54 , 55 , 56 ]. All participants were of Inuit decent, defined as having parents and/or grandparents born in Greenland.…”

“…All participants completed a standard questionnaire, including questions about demographic and lifestyle parameters. Venous blood samples were prepared for determination of POPs, fatty acids and metals and stored at −80 °C until analyses as described [ 16 , 18 , 19 , 49 , 50 , 53 , 54 , 55 , 56 ].…”

“…Whole blood levels of total mercury (Hg), lead (Pb) and selenium (Se) were measured using Inductively Coupled Plasma Mass Spectrometry (ICP–MS) at the accredited element laboratory, the Institute for Bioscience—Arctic Research Centre, Aarhus University, Denmark [ 49 , 53 ], and Le Centre de Toxicologie du Québec, Québec, Canada [ 58 , 59 ]. The whole blood samples were dissolved and decomposed by nitric acid in Teflon bombs, and blood metals were measured by ICP–MS in an Agilent 7500 cs apparatus [ 48 ].…”

Review of the environmental prenatal exposome and its relationship to maternal and fetal health

“…Specific linkages have been made between measures of prenatal exposures to metals and fetal health outcomes, including exposures to arsenic, cadmium, chromium, lead, and mercury [64][65][66][67]. For example, the effects of prenatal iAs exposure were evaluated in a pregnancy cohort located in Gómez Palacio, Mexico, and maternal urinary concentrations of iAs and select iAs metabolites showed negative associations with newborn birth weight, newborn length, and gestational age [68].…”