Effects of perfluoroalkyl and polyfluoroalkyl substances on soil structure and function

Soils are impacted at a global scale by several anthropogenic factors, including chemical pollutants. Among those, perfluoroalkyl and polyfluoroalkyl substances (PFAS) are of concern due to their high environmental persistence, and as they might affect soil health and functions. However, data on impacts of PFASs on soil structure and microbially-driven processes are currently lacking. This study explored the effects of perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutanesulfonic acid (PFBS) at environmental-relevant nominal concentrations (1 ~ 1000 ng g-1) on soil functions, using a 6-week microcosm experiment. We measured soil respiration, litter decomposition, enzyme and microbial activities, soil aggregates, and bacterial abundance. PFAS (even at 1 ng g-1 for PFBS) significantly increased the litter decomposition, associated with positive effects on bacterial abundance, and β-glucosidase activities. This effect increased with PFAS concentrations. Soil respiration was significantly inhibited by PFAS in the 3rd week, while this effect was more variable in week 6. Water-stable aggregates were negatively affected by PFOS and PFOA, possibly related to microbial shifts. The general microbial activities and β-D-cellobiosidase and phosphatase activities were barely affected by PFAS treatments. Our work highlights the potential effects of PFAS on soil health, and we argue that this substance class could be a factor of environmental change of potentially broad relevance in terrestrial ecosystem functioning.

Follicular Fluid Perfluoroalkyl and Polyfluoroalkyl Substances Are Associated With Adverse ART Outcomes in Women With Poor Ovarian Reserve

BackgroundPrevious evidence suggests that perfluoroalkyl and polyfluoroalkyl substances (PFASs) adversely affect ovarian function and female fecundity. However, the evidence remains insufficient to infer a direct relationship between PFAS exposure and adverse assisted reproductive technology (ART) outcomes. To fill this gap, we examined follicular fluid PFAS exposure and ART outcomes in patients with poor ovarian reserve (POR) in a prospective study.MethodsIn total, 147 women with POR were included. Eight PFASs were measured in follicular fluid (n=104) samples using simultaneous analysis by ultra-performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry. The PFAS contamination status of the patients’ follicular fluid and the association between characteristics and ART outcomes were investigated by logistic regression.ResultsAfter adjustment for age and BMI, PFOA, PFNA, PFHxS and ∑PFAS were strongly associated with a decreased probability of pregnancy (PFOA highest vs. lowest tertile: OR=1.95, 95% CI: 1.61, 2.38; PFNA highest vs. lowest tertile: OR= 3.0, 95% CI: 2.46, 3.68; PFHxS highest vs. lowest tertile: OR= 1.95, 95% CI: 1.61, 2.35; ∑PFAS second vs. lowest tertile: OR=3.31, 95% CI: 2.74, 3.89). PFOS and PFUnDA were inversely associated with failed implantation. No relationships were noted between failed implantation and other PFAS analytes. The same result was obtained when using live birth as an outcome measure.ConclusionsIn women with POR, follicular fluid PFAS exposure may decrease the probability of clinical pregnancy and live birth.