Association between maternal urinary speciated arsenic concentrations and gestational diabetes in a cohort of Canadian women
- DOI
- Language of the publication
- English
- Date
- 2018-10-12
- Type
- Article
- Author(s)
- Ashley-Martin, Jillian
- Dodds, Linda
- Arbuckle, Tye E.
- Bouchard, Maryse F.
- Shapiro, Gabriel D.
- Fisher, Mandy
- Monnier, Patricia
- Morisset, Anne-Sophie
- Ettinger, Adrienne S.
- Publisher
- Elsevier
Abstract
Background Epidemiological and toxicological evidence suggests that maternal total arsenic (As) levels are associated with an elevated risk of gestational diabetes (GDM). Uncertainty remains regarding the metabolic toxicity of specific arsenic species, comprised of both organic and inorganic sources of arsenic exposure. Objectives We assessed associations between speciated As and GDM using data from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study. Methods Concentrations of speciated As [(inorganic (trivalent, pentavalent)), methylated arsenic species metabolites (monomethylarsonic acid (MMA), dimethylarsinic acid (DMA)), and organic (arsenobetaine)] were measured in first trimester maternal urine samples. GDM cases were identified in accordance with Canadian guidelines. Multivariable regression models were used to estimate associations between speciated As and GDM, evaluate potential interaction between speciated As exposures, and assess fetal sex-specific findings. Results Among 1243 women who had a live, singleton birth and no previous history of diabetes, 4% met the diagnostic criteria for GDM. Our analyses focused on DMA and arsenobetaine as these were the subtypes with detectable concentrations in at least 40% of samples. Compared to women in the lowest tertile of DMA (<1.49 μg As/L), women with concentrations exceeding 3.52 μg As/L (3rd tertile) experienced an increased risk of GDM (aOR = 3.86; 95% CI: 1.18, 12.57) (p-value for trend across tertiles = 0.04). When restricted to women carrying male infants, the magnitude of this association increased (aOR 3rd tertile = 4.71; 95% CI: 1.05, 21.10). Conclusions These results suggest a positive relation between DMA and GDM; potential differences in risk by fetal sex requires further investigation.
Plain language summary
"Health Canada helps to protect the health of Canadians by assessing and managing the health risks associated with exposure to environmental contaminants. Arsenic is a naturally occurring chemical element found throughout our environment. It is used in the manufacture of a variety of products. Arsenic exists in different chemical forms, which can be classified into two groups: organic arsenic and inorganic arsenic. Arsenobetaine, an organic arsenic compound, is most commonly found in fish and shellfish. Inorganic arsenic may be found at low levels in rice, ground water and some types of seaweed. Some research has suggested that maternal total arsenic (As) levels are associated with an increased risk of gestational diabetes (GDM). However, the toxicity of specific forms of arsenic is uncertain. In this study, organic and inorganic forms of arsenic were measured in 1st trimester urine from pregnant women in the Maternal-Infant Research on Environmental Chemicals (MIREC) Study. Women with gestational diabetes were identified from medical records. Among 1243 women who had a live, singleton birth and no previous history of diabetes, 4% had gestational diabetes (GDM). Compared to women with the lowest levels of the DMA form of arsenic, women in the highest exposure group were associated with 4 times the risk of GDM. If the woman was carrying a male fetus, the association between DMA and GDM was 5 times higher. These results suggest a positive relation between certain arsenic forms and gestational diabetes, which may be particularly strong among women carrying a male fetus. This study was led by researchers at Dalhousie University, in collaboration with Health Canada scientists. Health Canada will continue to review new research relating to arsenic toxicity, particularly its effects on pregnant women and children."
Subject
- Health,
- Health and safety