Search Results (461)

Perfluorooctane sulfonamide (PFOSA), the direct precursor to perfluorooctane sulfonate (PFOS), is widely present in the environment. Research has indicated that PFOSA is cardiotoxic and hepatotoxic, but its impact on neurodevelopment remains unclear. In the current study, we observed that exposure of PFOSA caused neurodevelopmental toxicity in zebrafish embryos in a dose-dependent manner, as evidenced by impaired motor abilities and decreased swimming distance. We then demonstrated that PFOSA exposure downregulated the mRNA expression of neurodevelopment-related genes including a1-tubulin, elavl3, ache and dat. Moreover, PFOSA exposure resulted in dose-dependent oxidative stress, which triggers apoptosis in the brains of zebrafish larvae. We further showed that inhibition of the aryl hydrocarbon receptor (AhR) alleviated the oxidative stress and apoptosis induced by PFOSA, thereby counteracting the neurodevelopmental abnormalities in zebrafish larvae. In conclusion, these findings indicate PFOSA causes neurodevelopmental disorders by inducing oxidative stress and apoptosis through the AhR pathway. Full article

Per- and polyfluoroalkyl substances (PFASs) are highly chemically stable synthetic compounds. They are widely used in industrial and commercial sectors due to their ability to repel water and oil, thermal stability, and surfactant properties. However, this stability results in environmental persistence and bioaccumulation, posing significant health risks as PFASs eventually find their way into environmental media. Key PFAS compounds, including PerFluoroOctanoic Acid (PFOA), PerFluoroOctane Sulfonic acid (PFOS), and PerFluoroHexane Sulfonic acid (PFHxS), have been linked to hepatotoxicity, immunotoxicity, neurotoxicity, and endocrine disruption. In response to the health threats these substances pose, global regulatory measures, such as the Stockholm Convention restrictions and national drinking water standards, have been implemented to reduce PFAS exposure. Despite these efforts, a lack of universally accepted definitions or comprehensive inventories of PFAS compounds hampers the effective management of these substances. As definitions differ across regulatory bodies, research and policy integration have become complicated. PFASs are broadly categorized as either perfluoroalkyl acids (PFAAs), precursors, or other fluorinated substances; however, PFASs encompass over 5000 distinct compounds, many of which are poorly characterized. PFAS contamination arises from direct industrial emissions and indirect environmental formation, these substances have been detected in water, soil, and even air samples from all over the globe, including from remote regions like Antarctica. Analytical methods, such as primarily liquid and gas chromatography coupled with tandem mass spectrometry, have advanced PFAS detection. However, standardized monitoring protocols remain inadequate. Future management requires unified definitions, expanded monitoring efforts, and standardized methodologies to address the persistent environmental and health impacts of PFAS. This review underscores the need for improved regulatory frameworks and further research. Full article

An increase in the production of cationic dyes is expected over the next decade, which will have an impact on health and the environment. This work reports an adsorbent hydrogel composed of poly(acrylic acid) [poly(AA)] and Fe₃O₄ particles, prepared by radical polymerization and in situ co-precipitation of Fe³⁺ and Fe²⁺. This Fe₃O₄/poly(AA) composite hydrogel was used to evaluate its potential for removing the cationic dyes methylene blue (MB) and crystal violet (CV) from aqueous solutions. Instrumental characterization of the hydrogel was performed by FTIR, XRD, TGA, VSM, and physicochemical analysis (swelling and response to changes in pH). The results show that the incorporation of Fe₃O₄ particles improves the adsorption capacity of MB and CV dyes to a maximum adsorption of 571 and 321 mg/g, respectively, under the best conditions (pH 6.8, dose 1 g/L, time 24 h). The adsorption data best fit the pseudo-first order (PFO) kinetic model and the Freundlich isothermal model, indicating mass transfer via internal and/or external diffusion and active sites with different adsorption potentials. Moreover, the thermodynamic analysis confirmed that the adsorption process was spontaneous and exothermic, with physisorption as the dominant mechanism. In addition, the Fe₃O₄/poly(AA) hydrogel is capable of removing 95% of the dyes after ten consecutive adsorption–desorption cycles, demonstrating the potential of hydrogels loaded with Fe₃O₄ particles for the treatment of wastewater contaminated with dyes. Full article

This study investigated the occurrence, sources, and health risks of 21 per- and polyfluoroalkyl substances (PFAS) in commercially available shellfish and crustaceans from Zhejiang Province, China. Among the 306 samples analyzed, 87.9% contained at least one detectable PFAS. Perfluorooctanoic acid (PFOA) was the most frequently detected PFAS (64.7%), followed by perfluorooctanesulfonic acid (PFOS) (53.8%), perfluorononanoic acid (PFNA) (52.9%), and perfluorodecanoic acid (PFDA) (50.0%). The total PFAS in shellfish and crustaceans ranged from ND to 0.86 to 173 ng/g wet weight, with a median of 4.11 ng/g ww; the median concentration of total PFAS followed this order: marine crustaceans > fresh-water crustaceans > bivalves. Estimation of the human intake of adult consumers, the estimated daily intake (EDI) of Σ₂₁ PFAS ranged from 0.01 to 15.7 ng/kg bw/day; 0.31% of the adult study population had Σ₄PFAS exposure levels resulting in Hazard Quotient (HQ) values > 1, which may represent a potential public health concern for these individuals. Long-term exposure risks for specific PFCAs such as perfluoroundecanoic acid (PFUdA) and perfluorotridecanoic acid (PFTrDA) merit concern. Full article

Per- and polyfluoroalkyl substances (PFASs), called forever chemicals, persist in the environment and bioaccumulate, posing significant health risks. While epidemiological studies have linked exposure to specific PFAS types, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), to an increased incidence of various cancers, specific tumorigenesis mechanisms are unknown. Here, we investigated the potential molecular markers and signatures of perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) tumorigenesis. We performed a comprehensive transcriptomic analysis across multiple species and tissue types (N = 529) using PFOS and PFOA-exposed RNA-Seq samples. Conserved signatures demonstrate significant disruptions in seven key carcinogenic characteristics including metabolic reprogramming, epigenetic modifications, immune suppression, oxidative stress, and genomic instability. Tumorigenic markers such as SERPINE1, FN1, PLIN2, ALDOA, TRIB3, and TSC22D3 and their associated pathways may act independently or synergistically to promote a pro-tumorigenic environment. Additionally, PPARα, LARP1, ACOX1, MYC, and MYCN were identified as key upstream regulators supporting disruptions in lipid metabolism, oxidative stress, and uncontrolled cell proliferation. In liver samples, low concentrations of PFOS and PFOA were sufficient to exhibit tumorigenic signatures associated with tumorigenesis initiation and development. Inferred mechanisms of ccRCC initiation and development were linked to lipid metabolism dysregulation and immunosuppressive signaling. In prostate and testicular xenograft tumor models, carcinogenic mechanisms for tumor progression and promotion were hypothesized. Receptor-mediated signaling and protein synthesis was disrupted in prostate cancer and epigenetic alterations and ECM remodeling observed in testicular cancer. We also explored potential therapeutic rescue strategies, including chemopreventive agents for early intervention. All our findings provide hypotheses for PFOS/PFOA-induced tumorigenesis; however, experimental studies are required to establish translational relevance. All the R codes developed in this study are publicly available. Full article

Background: A persistent connection between the atria, known as a patent foramen ovale (PFO), is present in approximately 25% of the general population. PFO closure is indicated in patients under 60 years of age who have experienced an embolic stroke of undetermined source (ESUS) or transient ischemic attack (TIA) confirmed by neurological imaging, and in selected cases of peripheral embolism. Follow-up after the procedure is indicated to confirm the position of the occluder, assess the effectiveness of the closure, and evaluate any potential thrombus formation on the device. Methods: We analyzed data from 75 consecutive patients who underwent percutaneous PFO closure procedures and were followed up for at least one year. The procedure was performed under fluoroscopy and transesophageal echocardiography (TEE) guidance, and occluder size selection was made using TEE multiplanar imaging (MPR). All patients had standard transthoracic echocardiography (TTE) at 1 and 6–12 months after the procedure. To assess the long-term efficacy, contrast-enhanced transcranial Doppler (ce-TCD) was performed at 12 months to record high-intensity transient signals (HITSs). Cases with positive ce-TCD had TEE performed. Results: During follow-up evaluations after 1 and 6–12 months (TTE), we did not observe any device dislodgements, thrombi, or residual leaks visible in TTE. ce-TCD detected HITSs in eight patients, prompting additional TEE examinations performed in seven cases. In five out of seven patients, a leak around the occluder was identified, including two patients with grade 2 HITSs. Conclusions: Assessing the effectiveness of PFO occluder placement is crucial for the residual embolic risk and thus the necessity of antithrombotic therapy. Even low grades of HITSs observed in ce-TCD help to identify patients with residual leaks confirmed in TEE. Full article

Perfluorooctane sulfonate (PFOS), which is known for its environmental persistence and bioaccumulation, poses substantial impacts to aquatic ecosystems. This study assesses the toxic effects of PFOS in the freshwater snail Lanistes carinatus using biomarkers for antioxidant activity, neurotoxicity, and tissue damage. Snails exposed to PFOS (1, 3, 10 mg/L for 14 days) displayed lipid peroxidation (LPO) levels that increased by 16.3–67.5%, and malondialdehyde (MDA) levels that rose by 10.0–58.4%, indicating oxidative damage. Enzyme activities for glutathione S-transferase (GST), glutathione peroxidase (GPx), and catalase (CAT) increased, ranging from 10.0 to 58.3%, 10.0 to 58.4%, and 10.0 to 58.4%, respectively, whereas levels of reduced glutathione (GSH) dropped by 15.0–41.5% and Superoxide dismutase (SOD) decreased by 15.0–41.4%. The activity of acetylcholinesterase (AchE) was reduced by a range of 15.0–40.0%, suggesting neurotoxic effects. Histopathological changes in the digestive gland were also noted. Further research on the effects of PFOS on mollusks is required, and investigation into sex-specific toxicity is needed. This shed light on L. carinatus as a sentinel species, providing helpful information for the monitoring and regulation of PFOS in aquatic environments. Full article

This study investigated the bioaccumulation patterns of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and per- and polyfluoroalkyl substances (PFASs) in the liver and muscle tissues of wild boars (n = 39) and domestic pigs (n = 38) from Northern Italy. This research addressed a critical gap in our understanding of how different ecologies and diets influence the uptake of persistent organic contaminants in two closely related species, one domestic and one wild. Significant differences in contaminant profiles were observed, largely attributable to distinct exposure routes and feeding behaviors. Wild boars displayed different quantities and families of environmental contaminants, with higher PCB levels in muscle and PFASs in liver. Conversely, domestic pigs exhibited markedly higher PAH concentrations, primarily linked to contaminated feed in controlled agricultural settings. The liver consistently demonstrated a central role in toxicant retention across both species. Notably, concentrations of several regulated PFAS compounds in both wild and farmed animals exceeded EU maximum levels (sum of PFOS, PFOA, PFNA, and PFHxS: 1.3 µg/kg), raising significant food safety concerns. These findings underscore the critical need for continuous environmental biomonitoring, stricter control of contaminant sources in agriculture, and updated risk assessments for both wild and domestic meat products to protect animal welfare and human health. Full article

Perfluorooctane sulfonate (PFOS), a member of the per- and polyfluoroalkyl substance (PFAS) family, has been associated with adverse health effects, including potential links to autism spectrum disorder (ASD). This study investigates the impact of PFOS on metabolic, immunologic and behavioral profiles in BTBR-mt^B6 mice, a mouse strain that models ASD, to provide insights into the role of PFOS in ASD development and related health concerns. Three-month-old male and female BTBR-mt^B6 mice were divided into two groups (n = 6) and received daily administration of either 1 mg/kg PFOS or vehicle over a three-month period by gavage. Metabolic assessments included measurements of body weight and weekly blood glucose levels, glucose and insulin tolerance tests, organ weights, and body compositions (free fluid, fat and lean tissue). Immune profiling was conducted via flow cytometric analysis of splenic leukocytes, while behavioral evaluations included grooming, sniffing, and three-chamber social interaction tests. PFOS exposure disrupted glucose homeostasis, with both sexes exhibiting elevated blood glucose levels. Male mice showed impaired glucose tolerance, delayed glucose level recovery, and increased insulin resistance, while females displayed decreased insulin resistance. Additionally, PFOS exposure led to liver enlargement in both sexes. Behavioral assessments revealed heightened grooming in PFOS-treated males, commonly interpreted as stress- or ASD-related repetitive behaviors, whereas females exhibited reduced grooming, reflecting altered behavioral responses to exposure. Immune alterations were also sex specific. PFOS-treated males exhibited decreased granulocytes, increased macrophages, and enhanced surface expressions of B220 and CD40L. PFOS-treated females showed increased macrophages, B-cells, cytotoxic T-cells and CD25⁺ T-cell subsets, with enhanced surface expression of B220 and CD8, and reduced surface expression of Mac-3. In addition, PFOS exposure reduced spleen weight in females. Taken together, PFOS exposure induced significant physiological and behavioral changes in BTBR-mt^B6 mice, with sex-specific differences observed. These results raise concern that PFASs may contribute to the development or exacerbation of metabolic, immune and neurodevelopmental disorders, highlighting the need for sex-specific human risk assessment in environmental toxicology. Full article

Poly- and perfluorinated alkyl substances (PFAS) are a group of chemicals that are widely used, prevalent in the environment, associated with several toxic effects, and often have long half-lives. Their persistence and relevant toxicity are the primary causes of environmental and human health concerns, and they are referred to as “forever chemicals” because of their persistence. Environmental accumulation caused by slow natural biodegradation and subsequent long environmental half-lives leads to bioaccumulation and makes PFAS more likely to be chronically toxic with potential transgenerational effects. Ultimately, it is this persistence that causes the greatest concern because PFAS-contaminated sites need costly remediation techniques, or else the contaminated areas will not be available for proper economic development because of social and economic suppression. Non-PFAS, alternative Aqueous Film Forming Foams (AFFF) that are considered environmentally friendly, are being heavily considered or currently used for fire suppression instead of PFAS-based products. The bioaccumulation and toxicity of alternative AFFF are just starting to be studied. The purpose of this review is to discuss the basic environmental and human health effects of PFAS and alternative AFFF that propel regulatory changes, increase clean-up costs, reduce economic development, and drive the development of novel alternatives. Full article

Per- and polyfluoroalkyl substances (PFAS) are a global concern due to their persistence, ubiquity, and accumulation in living organisms. Found in soils, biosolids, water, and the food chain, they pose health risks such as hormone disruption, immune damage, reproductive issues, and cancer. Regulations mainly target older PFAS like PFOA and PFOS, while many newer PFAS, including breakdown products, are poorly understood in terms of distribution, behavior, and toxicity. To address this complex issue, this review offers a detailed overview of human exposure to PFAS and their toxic effects. It highlights biosolids as a key, understudied source of PFAS in the environment. The review also discusses limitations of testing, missing long-term cleanup data, and regulatory issues that neglect total exposure and vulnerable populations. Additionally, it evaluates, in the specific context of biosolids management, the effectiveness, scalability, benefits, and drawbacks of various treatment technologies, such as thermal processes (pyrolysis, incineration, smoldering combustion), advanced oxidation, adsorption, hydrothermal liquefaction, and biological degradation. This work combines environmental science, toxicology, and engineering to outline PFAS management in biosolids and proposes a research and policy plan. Focusing on regulating PFAS as a group, validating real-world results, and employing adaptable treatment strategies underscores the need for a coordinated, science-based effort to reduce PFAS risks worldwide. Full article

This study investigated the distribution of 29 legacy and emerging per- and polyfluoroalkyl substances (PFASs) in soil, nettles, invertebrates, and plasma and feathers of great tits (Parus major) of a terrestrial ecosystem near a fluorochemical plant. Additionally, the vertical distribution of PFASs in soil was assessed, as well as taxon-specific differences among terrestrial invertebrate species. Finally, associations between soil and biota, and among biological matrices, were assessed. Most accumulation profiles were dominated by long-chained PFASs, mainly perfluorooctane sulfonic acid (PFOS), while short-chained PFASs were less detected. Long-chained perfluoroalkyl carboxylic acids (PFCAs) adsorbed in the upper soil layers, while short-chained PFAS and perfluoroalkyl sulfonic acids (PFSAs) tended to migrate deeper. The several taxon-specific differences were likely due to dietary differences. Significant associations, especially for long-chained PFCAs and PFOS, were found among most matrices. This indicates that (1) these PFASs found in these matrices are most likely originating from the same pollution source, (2) there is a possible transfer of these PFASs between matrices, (3) there is bioaccumulation from one to another matrix, and (4) some matrices might be used as proxies to estimate PFAS concentrations in other terrestrial matrices. Finally, feathers accumulated more PFASs than plasma, as they were most likely exposed through different routes of exposure and PFAS affinity. Therefore, they are not suitable for internal PFAS monitoring but can provide complementary information about the exposure and about the presence/absence of PFASs in certain habitats. Full article

Perfluorooctane sulfonate (PFOS) is a representative persistent organic pollutant that exerts toxic effects on aquatic organisms. As an alternative to PFOS, sodium p-perfluorous nonenoxybenzene sulfonate (OBS) has been frequently detected in aquatic environments and human tissues in recent years. However, its toxic effects on aquatic organisms and potential health risks to humans remain unclear. Zebrafish embryos are transparent and amenable to in vivo manipulation and observation. Therefore, in the present study, we investigated its developmental toxicity in zebrafish embryos, with PFOS as the positive control. We exposed zebrafish embryos to different concentrations of OBS (15, 20, and 25 mg/L) and PFOS (15 mg/L) for 2–168 h post fertilization (hpf) and then examined physiological and gene expression changes. At 24 hpf, spontaneous twitches in the 25 mg/L OBS group decreased to (5 ± 0.34)/min. By 48 hpf, the 20 mg/L OBS group’s hatching rate was (47.78 ± 2.22)%, significantly lower than the control. At 72 hpf, heart rates in both the PFOS and OBS groups were elevated, at 82 ± 0.6, 84.5 ± 0.5, 89.4 ± 0.3, and 93.7 ± 0.4, respectively. Similarly to PFOS, OBS induced developmental toxicity in zebrafish embryos. In addition, both OBS and PFOS exposure downregulated the expression level of anti-apoptotic Bcl-2 in zebrafish embryos, with a notable 0.53-fold decrease observed in the 25 mg/L OBS group. Conversely, they upregulated the expression levels of pro-apoptotic Bax, Caspase-3, and Caspase-9, with Caspase-3 expression increasing 1.14-, 1.5-, and 1.7-fold in the 15 mg/L PFOS, 20 mg/L OBS, and 25 mg/L OBS groups, respectively. These OBS- and PFOS-induced changes in gene expression increased apoptosis, suggesting that OBS can induce developmental toxicity in zebrafish embryos, and that its effect is comparable to that of PFOS. Therefore, considering its aquatic toxicity, measures aimed at limiting or remediating OBS pollution in the environment are necessary. Full article

Purpose: Per- and polyfluoroalkyl substances (PFAS) comprise a class of man-made compounds widely utilized in manufacturing everyday consumer products. Experimental studies indicate that PFAS may interfere with iron regulation by hindering absorption or inducing oxidative stress. Nonetheless, epidemiological studies examining the association between PFAS exposure and a broad spectrum of iron-related biomarkers remain scarce. Approach and Results: In this study, data from the 2013–2018 National Health and Nutrition Examination Survey (NHANES) were analyzed, which included 5050 adults aged 18 and older. The relationships between six PFAS compounds, oral iron intake, and a comprehensive set of markers of iron homeostasis, including serum iron, unsaturated iron-binding capacity (UIBC), total iron-binding capacity (TIBC), transferrin saturation, ferritin, and transferrin receptor levels, were examined. Our findings revealed a negative association between both individual and total PFAS (sum of six PFAS) levels and oral iron intake. Additionally, serum iron and transferrin saturation levels exhibited significant positive correlations with all PFAS compounds, whereas ferritin was positively correlated with all PFAS compounds except n-perfluorooctanoic acid (n-PFOA). UIBC and transferrin receptor showed significant negative correlations with all PFAS compounds, while TIBC was significantly negatively correlated with n-perfluorooctane sulfonic acid (n-PFOS), perfluoromethylheptane sulfonic acid isomers (sm-PFOS), perfluorohexane sulfonic acid (PFHxS), and the total PFAS. Conclusions: Higher PFAS exposure was associated with altered iron status biomarkers While this cross-sectional study cannot establish causality, the observed associations raise the possibility that PFAS exposure may influence iron absorption. These findings emphasize the need for additional research into the potential impact of PFAS exposure on iron homeostasis. Full article

Sodium p-perfluorous nonenoxybenzenesulfonate (OBS) has been proposed as a substitute for perfluorooctanesulfonic acid (PFOS), yet it has garnered increasing attention due to its environmental persistence and potential toxicity. Despite these concerns, the neurotoxic mechanisms of OBS remain unclear. This study investigates and compares the neurotoxic effects and mechanisms of OBS and PFOS in Caenorhabditis elegans. L4-stage worms were exposed to OBS (0.1–100 μM) or PFOS (100 μM) for 24 h. Neurobehavioral analysis showed that OBS exposure induced concentration-dependent neurobehavioral deficits, with 100 μM OBS significantly reducing pharyngeal pumping rate (29.8%), head swing frequency (23.4%), and body bending frequency (46.6%), surpassing the effects of PFOS. Both compounds decreased the fluorescence intensity of dopaminergic, glutamatergic, and γ-aminobutyric acid neurons and downregulated neurotransmitter-associated genes. They also increased ROS generation and inhibited antioxidant gene expression. Molecular docking revealed that OBS had a stronger binding affinity to p38 MAPK key protein (PMK-1) than PFOS. OBS and PFOS upregulated pmk-1 and skn-1, modulating oxidative stress and neuronal function. pmk-1 mutation differentially affected OBS-induced neurobehavioral changes and gene expression alterations. Our findings indicate that OBS exhibits stronger neurotoxicity than PFOS in Caenorhabditis elegans, mediated through the PMK-1 pathway. These results highlight the need for further investigation into the safety of OBS as a PFOS alternative. Full article