title: Arsenic levels among pregnant women and newborns in Canada: Results from the Maternal-Infant Research on Environmental Chemicals (MIREC) cohort.
abstract: Arsenic is a common environmental contaminant from both naturally-occurring and anthropomorphic sources and human exposure can be detected in various tissues. Its toxicity depends on many factors including the chemical form, valence state, bioavailability, metabolism and detoxification within the human body. Of paramount concern, particularly with respect to health effects in children, is the timing of exposure as the prenatal and early life periods are more susceptible to toxic effects. The Maternal-Infant Research on Environmental Chemicals (MIREC) cohort was established to obtain national-level biomonitoring data for approximately 2,000 pregnant women and their infants between 2008 and 2011 from 10 Canadian cities. We measured total arsenic (As) in 1st and 3rd trimester maternal blood, umbilical cord blood, and infant meconium and speciated arsenic in 1st trimester maternal urine. Most pregnant women had detectable levels of total arsenic in blood (92.5% and 87.3%, respectively, for 1st and 3rd trimester); median difference between 1st and 3rd trimester was 0.1124µg/L (p<0.0001), but paired samples were moderately correlated (Spearman r=0.41, p<0.0001). Most samples were below the LOD for umbilical cord blood (50.9%) and meconium (93.9%). In 1st trimester urine samples, a high percentage (>50%) of arsenic species (arsenous acid (As-III), arsenic acid (As-V), monomethylarsonic acid (MMA), and arsenobetaine (AsB)) were also below the limit of detection, except dimethylarsinic acid (DMA). DMA (>85% detected) ranged from <LOD to 64.42 (95th percentile: 11.99)µgAs/L. There was a weak but significant correlation between total arsenic in blood and specific gravity-adjusted DMA in urine (Spearman r=0.33, p<0.0001). Among this population of pregnant woman and newborns, levels of arsenic measured in blood and urine were lower than national population figures for Canadian women of reproductive age (20-39 years). In general, higher arsenic levels were observed in women who were older, foreign-born (predominantly from Asian countries), and had higher education. Further research is needed to elucidate sources of exposure and factors that may influence arsenic exposure in pregnant women and children.
authors.affiliation: University of Michigan School of Public Health, Department of Nutritional Sciences, 1415 Washington Heights, Ann Arbor, MI 48109-2029 USA. Electronic address: aettinge@umich.edu.
authors.forename: Adrienne S
authors.initials: AS
authors.lastname: Ettinger
authors.affiliation: Population Studies Division, Healthy Environments and Consumer Safety Branch, Health Canada, A.L. 0801 A, 50 Colombine Dr., Ottawa, ON, Canada K1A 0K9. Electronic address: Tye.Arbuckle@canada.ca.
authors.forename: Tye E
authors.initials: TE
authors.lastname: Arbuckle
authors.affiliation: Population Studies Division, Healthy Environments and Consumer Safety Branch, Health Canada, A.L. 0801 A, 50 Colombine Dr., Ottawa, ON, Canada K1A 0K9.
authors.forename: Mandy
authors.initials: M
authors.lastname: Fisher
authors.affiliation: Population Studies Division, Healthy Environments and Consumer Safety Branch, Health Canada, A.L. 0801 A, 50 Colombine Dr., Ottawa, ON, Canada K1A 0K9.
authors.forename: Chun Lei
authors.initials: CL
authors.lastname: Liang
authors.affiliation: Population Studies Division, Healthy Environments and Consumer Safety Branch, Health Canada, A.L. 0801 A, 50 Colombine Dr., Ottawa, ON, Canada K1A 0K9.
authors.forename: Karelyn
authors.initials: K
authors.lastname: Davis
authors.affiliation: Laboratoire de toxicologie, Institut national de santé publique du Québec, 945, avenue Wolfe, Québec, QC, Canada G1V 5B3.
authors.forename: Ciprian-Mihai
authors.initials: CM
authors.lastname: Cirtiu
authors.affiliation: Laboratoire de toxicologie, Institut national de santé publique du Québec, 945, avenue Wolfe, Québec, QC, Canada G1V 5B3.
authors.forename: Patrick
authors.initials: P
authors.lastname: Bélanger
authors.affiliation: Laboratoire de toxicologie, Institut national de santé publique du Québec, 945, avenue Wolfe, Québec, QC, Canada G1V 5B3.
authors.forename: Alain
authors.initials: A
authors.lastname: LeBlanc
authors.affiliation: Department of Obstetrics and Gynecology, University of Sherbrooke, 3001, 12th avenue Nord, Sherbrooke, QC, Canada J1H 5N4; CHU Sainte-Justine Research Center, Mother and Child University Hospital Center, 3175 chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5.
authors.forename: William D
authors.initials: WD
authors.lastname: Fraser
mesh_terms: D000328:Adult; D001151:Arsenic / Q000097:blood* / Q000652:urine*; D002170:Canada; D004785:Environmental Pollutants / Q000097:blood* / Q000652:urine*; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D006801:Humans; D007231:Infant, Newborn; D018811:Maternal Exposure; D008470:Meconium / Q000737:chemistry; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000097:blood; D011263:Pregnancy Trimester, Third / Q000097:blood; D012959:Socioeconomic Factors
chemical_list: D004785:Environmental Pollutants; D001151:Arsenic
keywords: Arsenic; Biological marker; Blood; Pregnancy; Speciation; Urine