Early-life exposure to per- and polyfluoroalkyl substances and gut microbial composition
Year: 2022
Type: conference-abstract
Abstract: Background and Aim: Human milk is an under-appreciated source of toxic exposures, including immunomodulatory per- and polyfluoroalkyl substances (PFAS), for breastfed infants. The immune-related effects of PFAS may, in part, be due to alterations of the microbiome. We aimed to identify changes in the infant gut microbiome related to milk PFAS exposure. Methods: In the New Hampshire Birth Cohort Study, PFAS were quantified in human milk samples from ~six weeks postpartum using solid-phase extraction coupled to high-performance liquid chromatography-isotope dilution tandem mass spectrometry. A molar sum (ΣPFAS) was calculated. Caregivers collected infant stool samples at six weeks (n=116) and/or one year postpartum (n=119). Stool DNA was extracted and underwent metagenomic sequencing. We profiled bacterial species and KEGG Orthologies (KOs) using BioBakery pipelines. Diversity was quantified with the Shannon Index. We estimated the association of PFAS with alpha diversity and relative abundances of species and KOs with linear regression. Single- and multi-pollutant models adjusted for confounders and predictors of the microbiome, with missing covariate data imputed. Each outcome timepoint was considered separately and analyses at six weeks were restricted to infants who were exclusively fed human milk (n=90). Results: Perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) were detected in 94% and 83% of milk samples, respectively. PFOS was associated with increased Shannon Index at six weeks [β=0.24 per PFOS doubling, (95%CI: 0.03, 0.45), p=0.03]. Estimates were stronger in multi-pollutant than single-pollutant models, and among complete cases. ΣPFAS was associated with one-year-old Bacteroides vulgatus relative abundance [(β=-2.48 % per doubling (-3.77, -1.18), FDR q=0.05]. No other associations were observed. Conclusions: PFAS may increase diversity of the infant gut microbiome and alter the relative abundance of cardiometabolically-active bacteria. Additional analyses may highlight susceptible populations and identify related health outcomes. Keywords: per- and polyfluoroalkyl substances, microbiome, human milk
Source: ISEE Conference Abstracts
Language: English
Subfield: Environmental Chemistry
Field: Environmental Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4317181752