Prenatal perfluoroalkyl substances and newborn anogenital distance in a Canadian cohort
- DOI
- Language of the publication
- English
- Date
- 2020-04-10
- Type
- Article
- Author(s)
- Arbuckle, Tye E.
- MacPherson, Susan
- Foster, Warren G.
- Sathyanarayana, Sheela
- Fisher, Mandy
- Monnier, Patricia
- Lanphear, Bruce
- Muckle, Gina
- Fraser, William D.
- Publisher
- Elsevier
Abstract
Exposure to the man-made chemicals perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS) and perfluorohexanesulfonate (PFHxS) is widespread. These perfluoroalkyl substances (PFASs) have been associated with androgenic endocrine-disrupting properties; however, the evidence is equivocal and few human studies have examined the association between prenatal exposure to PFASs and markers of androgenic endocrine disruption such as changes in anogenital distance (AGD). In the MIREC cohort, PFOA, PFOS and PFHxS were analyzed in first trimester maternal plasma. AGD was measured in 205 male and 196 female newborns. The change in estimate procedure was used to identify confounders by sex and AGD in multiple linear regression models. Geometric mean plasma concentrations (95% CI) for PFOA, PFOS and PFHxS were 1.71 (1.61, 1.81), 4.40 (4.18, 4.64) and 1.15 (1.06, 1.25) μg/L, respectively. A one-unit increase in natural log transformed PFOA was associated with a 1.36 mm (95% CI 0.30, 2.41) increase in anoscrotal distance, adjusting for household income, active smoking status during pregnancy and gestational age. However, when examined by quartiles, a non-monotonic pattern was observed with wide confidence intervals. No consistent patterns were observed between maternal PFAS concentrations and female AGDs. This study found no clear evidence that maternal plasma concentrations of PFOS, PFOA or PFHxS were associated with shorter infant anogenital distance in males or any change in AGD in females. Whether the positive association observed between longer anoscrotal distance and PFOA is real or would have any long-lasting effect on the reproductive health of males is unknown and needs to be investigated further.
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. Most Canadians have levels of perfluoroalkyl substances (PFASs) in their blood. PFASs are persistent pollutants used in the production of common household and consumer goods (e.g., cookware, clothing, food packaging). Pregnancy is a time of increased sensitivity to the potential adverse effects of endocrine disrupting chemicals. Few studies have examined maternal exposure to PFASs and markers of endocrine disruption such as changes in anogenital distance of infants. Anogenital distance (AGD) is the distance between the anus and penis in infant boys and between the anus and clitoris in infant girls. In this research, three PFASs (PFOA, PFOS and PFHxS) were measured in first trimester blood samples in women participating in the MIREC Study. Anogenital distances were measured in their babies shortly after birth (205 boys and 196 girls). No consistent associations were observed between PFAS levels in blood of mothers and AGD in their female infants. In infant boys, increases in mothers’ level of PFOA were associated with a small increase in AGD. Previous research has suggested that shorter AGD in boys may be associated with poorer reproductive health in adulthood. It is unknown whether the slightly longer AGD in boys associated with PFAS exposure in this study is real or due to chance, or if true, would have any long-lasting effect on their reproductive health. Further research on other populations is needed to confirm these findings.
Subject
- Health,
- Health and safety