Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a diverse family of fluorine-containing chemicals which possess unique chemical properties that render them near indestructible. The stability of these chemicals saw their widespread use, manufacture and distribution resulting in the pervasive exposure of humans and animals. As such PFAS are now considered a ubiquitously persistent environmental contaminant. Once absorbed into the body, PFAS bioaccumulates and can be transferred via the placenta and through milk during lactation. It is therefore not unsurprising that PFAS has been readily detected in human blood and breast milk, and in some occupationally exposed populations has been found in concentrations 1000-fold higher than the general population. Despite this, there remains no clear consensus on the biological impacts of PFAS exposure and consequently, the public demand for a definitive health risk assessment of PFAS continues to go unmet.
We therefore designed this study to assess the effects of gestational and post-natal exposure of a cocktail of nine PFAS chemicals, formulated to mimic that of environmental samples, on mouse development. Adult female mice were administered PFAS (or sham) via their drinking water three days prior to mating and continued to be administered PFAS from conception through to weaning (3 weeks post-birth). Plug and pregnancy rates were found to be unaffected by PFAS exposure, as was pregnancy duration. Litter size was however dramatically decreased for our PFAS dams (P< 0.048). Additionally, the pups born from PFAS exposed mothers were significantly heavier come weaning (day 21, P < 0.0001) and displayed altered reproductive millstones, as determined by vaginal opening, which were reflective of expedited puberty (P< 0.016). Intriguingly, we also saw that the pups of PFAS exposed mothers display altered behaviour, including reduced anxiety-like and increased risk-taking behaviours reflective of an attention-deficit disorder phenotype. This study, therefore, presents new evidence that PFAS impacts offspring health and development. Our longer-term studies will continue to explore the effects of these changes and will assess the integrity of the endocrine and reproductive systems given these preliminary results. We will also conduct more nuanced behavioural testing focusing on hyperactivity, learning, risk-taking and alcohol consumption behaviours.