Developmental PFAS Exposure Impairs Learning and Memory in C. elegans
Currie SD, Ji Y, Huang Q, Wang JS, Tang L. The impact of early life exposure to individual and combined PFAS on learning, memory, and bioaccumulation in C. elegans. Environmental pollution 2024;363(Pt 2):125257. doi: 10.1016/j.envpol.2024.125257.
Background: Per- and polyfluoroalkyl substances (PFAS) are highly persistent environmental contaminants associated with neurodevelopmental and behavioral effects. Due to their stability and widespread presence, they accumulate in living organisms and may disrupt learning and memory processes. Caenorhabditis elegans serves as a sensitive and cost-effective in vivo model for investigating neurotoxicity and bioaccumulation mechanisms relevant to human health.
Hypothesis: This study hypothesized that early-life exposure to individual and combined PFAS impairs learning and memory in C. elegans in a concentration-dependent manner and that these effects are linked to PFAS bioaccumulation within the organism.
Methods: The authors exposed synchronized L1-stage C. elegans to eleven individual PFAS and a reference mixture at concentrations ranging from 0.1 to 200 μM. Learning and memory endpoints were analyzed using the WormLab Imaging System and WormLab, which quantified pirouettes and absolute peristaltic speed, respectively. PFAS bioaccumulation was determined by UHPLC–MS and expressed as bioconcentration factors.
Results: Exposure to PFAS significantly reduced learning and memory in a time- and concentration-dependent manner. PFOS and PFBS caused the greatest inhibition at 100–200 μM, and all PFAS impaired behavior after 48 h. PFBS and PFOS also showed the highest internal accumulation and bioconcentration factors. The PFAS mixture produced additive inhibitory effects on learning and memory without exceeding individual PFOS or PFBS toxicity.
Conclusions: The findings demonstrate that PFAS exposure during development impairs learning and memory in C. elegans and that these neurobehavioral effects correlate with compound bioaccumulation. The results highlight potential developmental neurotoxicity risks from combined PFAS exposure.
