Concentrations of perfluoroalkyl substances in foods and the dietary exposure among Taiwan general population and pregnant women

There's Something in What We Eat: An Overview on the Extraction Techniques and Chromatographic Analysis for PFAS Identification in Agri-Food Products

Per- and polyfluorinated alkyl substances (PFASs) are a group of anthropogenic chemicals used in a range of industrial processes and consumer products. Recently, their ubiquitous presence in the environment as well as their toxicological effects in humans have gained relevant attention. Although the occurrence of PFASs is widely investigated in scientific community, the standardization of analytical method for all matrices still remains an important issue. In this review, we discussed extraction and detection methods in depth to evaluate the best procedures of PFAS identification in terms of analytical parameters (e.g., limits of detection (LODs), limits of quantification (LOQs), recoveries). Extraction approaches based on liquid-liquid extraction (LLE), alkaline digestion, and solid phase extraction (SPE), followed by liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) analysis are the main analytical methods applied in the literature. The results showed detectable recoveries of PFOA and PFOS in meat, milk, vegetables, eggs products (90.6-101.2% and of 89.2-98.4%), and fish (96-108%). Furthermore, the low LOD and LOQ values obtained for meat (0.00592-0.01907 ng g-1; 0.050 ng g-1), milk (0.003-0.009 ng g-1; 0.010-0.027 ng g-1), fruit (0.002-0.009 ng g-1; 0.006-0.024 ng g-1), and fish (0.00369-0.017.33 ng g-1; 0.05 ng g-1) also confirmed the effectiveness of the recent quick, easy, cheap, effective, rugged, and safe method (QuEChERS) for simple, speedy, and sensitive ultra-trace PFAS analysis.

Influence of Area, Age and Sex on Per- and Polyfluorinated Alkyl Substances Detected in Roe Deer Muscle and Liver from Selected Areas of Northern Italy

Due to their physicochemical properties, per- and polyfluorinated alkyl substances (PFASs) persist and bioaccumulate in living organisms, causing adverse health effects. Since exposure to xenobiotics is influenced by factors related to both the living organism and the considered compounds, biomonitoring PFASs' presence in the environment is of crucial importance. This study aimed to detect and quantify 15 PFASs in the muscle and liver of 40 roe deer from a specific area in Northern Italy by UPLC-HRMS. In the roe deer, liver PFAS concentrations were higher than those seen in muscle (p < 0.05). Although PFAS content in animals from urbanized areas was higher than those found in deer from rural areas, this difference was not statistically significant. In female roe deer, the concentration was higher than in males (p < 0.05); moreover, older animals showed higher concentrations of PFASs in the liver than younger animals (p < 0.05). In conclusion, the amount of PFASs was higher in tissues from roe deer belonging to urbanized areas, showing that this species might serve as a good bioindicator due to its territorial behavior. PFAS content was significantly higher in female roe deer, although the reason is not fully known. Finally, PFAS concentration was higher in the liver of older animals, probably due to compromised hepatic function.

Worldwide serum concentration-based probabilistic mixture risk assessment of perfluoroalkyl substances among pregnant women, infants, and children

Pregnant women, infants, and children are particularly vulnerable to perfluoroalkyl substances (PFASs), yet little is known about related health risks. Here, we aimed to study the four main PFASs: perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorohexanesulfonic acid (PFHxS), and assess the mixture risks of co-exposure to PFASs for pregnant women and children as well as for infants associated with maternal PFAS exposure at national and global scales, based on biomonitoring data on serum. We conducted a literature search and aggregated 69 data sources across 22 countries/regions from 2010 to 2020 to profile the serum concentrations of these four PFASs in pregnant women and children. Based on toxicity assessments by regulatory authorities, we determined conservative reference levels (RfLs) in the serum for the primary adverse effects of PFASs, including hepatic, developmental, and immune effects. The cumulative hazard quotient (HQ) was combined with probabilistic analysis to compare serum levels with RfLs and to quantify mixture risks. Our analysis revealed that PFOS was the dominant PFAS in maternal and child serum worldwide, with median levels 2.5-10 times higher than those of PFOA, PFNA, and PFHxS. The estimated global median serum levels of PFOS were 6.17 ng/mL for pregnant women and 4.85 ng/mL for children, and their immune effects in pregnant women and children are concerning as their cumulative HQs could exceed 1. For infants, the cumulative HQs for both developmental and immune effects could also be > 1, suggesting that maternal exposure to PFASs during pregnancy and breastfeeding may pose concerns for infant development and immunity. Our national and global serum database and risk assessment offer additional insights into PFAS exposures and mixture risks in susceptible populations, serving as a reference for evaluating the effectiveness of ongoing regulatory mitigation measures.

Health Risk Exposure Assessment of Migration of Perfluorooctane Sulfonate and Perfluorooctanoic Acid from Paper and Cardboard in Contact with Food under Temperature Variations

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are extensively used in food-contact paper and cardboard. However, they may migrate from food-contact materials to food, and the migration rate may be increased at elevated temperatures. In addition, there is a positive association of PFOS/PFOA levels with total cholesterol. Therefore, this study aims to assess the human health risk of increased total cholesterol associated with long-term exposure to PFOS and PFOA migration from food-contact paper and cardboard under temperature variation scenarios in adults. An exposure assessment was performed using an uptake dose model to estimate the uptake doses of PFOS and PFOA for the high-, intermediate-, and low-exposure scenarios. Benchmark dose (BMD) modeling was conducted to describe the dose-response relationships between PFOS/PFOA and total cholesterol levels. Finally, a margin of exposure (MOE) approach was used to characterize the risk. The results of the exposure assessment showed that PFOS and PFOA uptake doses in the high-exposure scenarios were around one and two orders of magnitude greater than those in the intermediate- and low-exposure scenarios, respectively. Under high-exposure scenarios, the uptake levels of hundredth-percentile PFOS and PFOA at high temperatures may raise health concerns (MOE < 1). This study provides a methodology to assess the health risks associated with exposure to migration of food contaminants from various types of paper and cardboard that come into contact with food.

Residue Distribution and Daily Exposure of Per- and Polyfluoroalkyl Substances in Indica and Japonica Rice

Per- and polyfluoroalkyl substances (PFAS) have excellent chemical stability but have adverse environmental impacts of concern. Furthermore, bioaccumulation of PFAS in rice varieties─which is the essential staple food crop in Asia─has not been verified. Therefore, we cultivated Indica (Kasalath) and Japonica rice (Koshihikari) in the same Andosol (volcanic ash soil) paddy field and analyzed the air, rainwater, irrigated water, soil, and rice plants for 32 PFAS residues, throughout the cultivation to human consumption. During the rice cultivation period, the cultivation environment in atmospheric particulate matter (PM) constituted perfluoroalkyl carboxylic acids (PFCAs), with minimal perfluorinated sulfonic acids (PFSAs). Furthermore, perfluorooctanesulfonic acid (PFOS) migrates at a PM > 10 to drop in a cultivation field and was conducive to leakage and accumulation of PFCAs in air particles in the field environment. Moreover, precipitation was a sources of irrigation water contamination, and cultivated soil with a high carbon content could capture PFSAs and PFCAs (over C₁₀). There were no major differences in residual PFAS trends in the rice varieties, but the distribution of PFAS in the growing soil, air, and rainwater differed. The edible white rice part was mainly affected by irrigation water in both varieties. Monte Carlo simulations of daily exposure assessments of PFOS, PFOA, and perfluorononanic acid showed similar results for Indians consuming Indica rice and Japanese consuming Japonica rice. The results indicate that the ultratrace PFAS residue concentrations and their daily exposure were not cultivar-specific.

Co-variate adjusted associations between serum concentrations of selected perfluoroalkyl substances and urinary concentrations of selected arsenic species

Data from National Health and Nutrition Examination Survey for 2011-2012 were used to estimate associations of the serum concentrations of perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluoroundecanoic acid (PFUnDA), and 2-(N-methyl-perfluorooctane sulfonamido) acetic acid (Me-PFOSA) with urinary concentrations of total arsenic (UAS), inorganic arsenic (IAS), arsenobetaine (UAB), and dimethyl arsinic acid (UDMA) among US adults aged >  = 20 years. Concentrations of PFNA were positively associated with all four arsenic variables but statistical significance was observed for IAS only (β = 0.33364, P = 0.04). Concentrations of PFDA were positively associated with UAS (β = 0.20688, P = 0.01), IAS (β = 0.23712, P = 0.02), and UAB (β = 0.26049, P = 0.02). Concentrations of PFUnDA were positively associated with UAS (β = 0.49946, P < 0.01), IAS (β = 0.51782, P < 0.01), UAB (β = 0.62924, P < 0.01), and UDMA (β = 0.26375, P < 0.01). Concentrations of Me-PFOSA with PFAS were inversely associated with every PFAS but statistical significance was observed for UDMA only (β =  - 0.05613, P = 0.03). PFOA, PFHxS, and PFOS were, in general, negatively associated with concentrations of all four arsenic variables but without reaching statistical significance. Positive associations of PFDA, PFNA, and PFUnDA with arsenic necessitate investigation about impact of the co-exposure of these PFAS with arsenic and their impact on health. Fluorinated carbon chain length > 8 as opposed to ≤ 8 may have a role in defining associations of PFAS with arsenic.

Association between perfluoroalkyl substances exposure and the prevalence of nonalcoholic fatty liver disease in the different sexes: a study from the National Health and Nutrition Examination Survey 2005-2018

There is evidence that perfluoroalkyl substances (PFASs) have effects on liver toxicity, and the effects may exhibit sex differences. Our study aims to explore the association between exposure to four PFASs (perfluorooctanoic acid, PFOA; perfluorooctane sulfonate, PFOS; perfluorohexane sulfonate, PFHxS; and perfluorononanoate, PFNA) and the risk of nonalcoholic fatty liver disease (NAFLD) in adults ≥ 20 years old in the US population. The data were based on the National Health and Nutrition Examination Survey (NHANES) 2005-2018. We used Poisson regression to explore the association between the four PFASs and NAFLD. We included 3464 participants; of these, 1200 (34.64%) individuals were defined as having NAFLD, and the prevalence of NAFLD was 39.52% in men and 30.40% in women. After Poisson regression, among the premenopausal and postmenopausal and total women, PFOA had a significantly positive association with NAFLD (p < 0.05). After principal component analysis, the "composite PFAS" was associated with NAFLD in postmenopausal and total women, and the RRs (95% CIs) were 1.306 (1.075, 1.586) and 1.161 (1.007, 1.339), respectively. In adults, we found that PFASs were associated with NAFLD, and the associations varied by sex, particularly for PFOA and PFNA, which had a positive association with NAFLD in women.

Infant formula and baby food as a source of perfluoroalkyl substances for infants

The present study reports infants' exposure to fourteen perfluoroalkyl substances (PFASs) in infant formula and baby food. First infant milk, follow-on milk and three types of baby food were analyzed: a variety made of fruits and vegetables, a variety with added fish and one containing meat. The mean lower-bound (LB) concentration of ∑14 PFASs was 0.22 μg/kg wet weight (w.w.) in first infant milk and 0.24 μg/kg w. w. In follow-on milk. Lower levels were noticed in baby food, where the mean LB concentration of ∑14 PFASs was in a 0.019-0.025 μg/kg w. w. Range. Perfluorotetradecanoic acid was found to be in the highest concentration both in baby formula and baby food. Dietary intake of ∑14 PFASs (LB concentration) via infant formula was in 0.3-83.1 ng/kg body weight (b.w.) and 0.3-31.1 ng/kg b. w ranges for first infant milk and follow-on milk respectively. The mean dietary intakes of ∑14 PFASs via one serving of baby food were similar for three varieties and were in a 0.46-0.57 ng/kg b. w. Range. Dietary intake of ∑4 PFASs was negligible in regard to the tolerable weekly intake of 4.4 ng/kg b. w. Recently established by the European Food Safety Authority. This preliminary study brings new information on infant exposure to PFASs in Poland. It is suggested that more sensitive methods be used in the future, and since there are many types of infant foods with different compositions of ingredients, more studies should be conducted.

Background per- and polyfluoroalkyl substances (PFAS) in laboratory fish diet: Implications for zebrafish toxicological studies

Current attention is focused on determining the potential for per- and polyfluoroalkyl substances (PFAS) to adversely impact human health. Zebrafish are a popular biological model because they share early development pathways with humans. A dietary exposure paradigm is growing in popularity in the zebrafish model because the outcomes often translate to humans. To create a diet of known composition, it is crucial to understand background PFAS levels present in zebrafish diet. Background PFAS, if present, potentially confounds interpretation of toxicological data. To date, no studies document the PFAS background levels in laboratory fish diet and there is only limited information on some pet foods. The objective of this study was to develop and validate an analytical method for up to 50 target PFAS in high lipid and protein content laboratory fish diets and pet foods. Long-chain perfluoroalkyl carboxylic acids (C9-C13) and perfluorooctane sulfonate (PFOS) were quantified in 11 out of 16 laboratory fish diets and in three out of five pet fish foods. Foods for pet birds, lizards, and dogs were below the limit of detection for all PFAS. In two of the laboratory fish diets, PFOS concentrations were >1.3 ng/g and the total PFAS for the three laboratory fish diets exceeded 1.0 ng/g. Hundreds of biomedical laboratories across the world utilize these commercial laboratory fish diets, and these results indicate that numerous zebrafish colonies may be inadvertently receiving significant dietary PFAS exposures. In light of this new information, it is critical to design PFAS studies with appropriate controls with measured background PFAS concentrations in the diet and to urge caution when interpreting the results.

Global DNA methylation mediates the association between serum perfluorooctane sulfonate and carotid intima-media thickness in young and middle-aged Taiwanese populations

PURPOSE

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a group of synthetic chemicals used in the manufacture of many everyday products. Previous reports have shown PFAS exposure may contribute to cardiovascular diseases (CVD). Recent studies have also identified a critical role for DNA methylation, a model of epigenetic regulation, in the pathogenesis of CVD. Additionally, PFAS has been shown to affect DNA methylation. Our previous study reported the positive association between serum perfluorooctane sulfonate (PFOS) levels and mean carotid intima-media thickness (CIMT), a biomarker of arteriosclerosis, in a cohort composed of adolescent and young adult Taiwanese. However, the contribution of DNA methylation in the mechanism of PFOS-induced arteriosclerosis has never been explored in previous literature.

APPROACH AND RESULTS

In this cross-sectional study, we included 1425 young and middle-aged Taiwanese individuals (12-63 years) to investigate the correlation between serum PFOS levels, 5mdC/dG (a global DNA methylation marker) and the mean CIMT. We showed that the positive association between serum PFOS levels, 5mdC/dG, and mean CIMT. The regression coefficients of mean CIMT with a one-unit increase in ln-PFOS concentration were higher when the levels of 5mdC/dG were above the 50th percentile in the multiple regression analysis. In the structural equation model (SEM), the results showed that serum PFOS levels were directly correlated with mean CIMT and indirectly correlated with CIMT through 5mdC/dG.

CONCLUSIONS

Our results showed that PFOS exposure has direct associations on arteriosclerosis and indirect direct associations on arteriosclerosis through DNA methylation. The results suggest that DNA methylation might regulate the relationship between PFOS and arteriosclerosis in the study subjects. Additional works are required to understand the causal inference between PFOS, DNA methylation, and arteriosclerosis.

Dietary Perfluorohexanoic Acid (PFHxA) Exposures in Juvenile Zebrafish Produce Subtle Behavioral Effects across Generations

Ubiquitous anthropogenic contaminants of concern, per- and polyfluoroalkyl substances (PFAS) are frequently detected in the environment and human populations around the world. Diet is a predominate route of human exposure, and PFAS are frequently measured in food. Manufacturing trends have shifted from legacy PFAS to shorter-chain alternatives that are suggested to be safer, such as perfluorohexanoic acid (PFHxA). However, the current amount of data to support safety assessments of these alternatives is not yet sufficient. The present study investigated the effects of a 42-day dietary exposure to 1, 10, or 100 ng/g PFHxA in juvenile zebrafish. The zebrafish model was leveraged to interrogate morphometrics, fecundity, and numerous behavior endpoints across multiple generations. Dietary PFHxA exposure did not result in measurable body burden and did not affect growth, fecundity, adult social perception behavior, or associative learning. PFHxA exposure did induce abnormal adult anxiety behaviors in the F0 generation that persisted transgenerationally in the F1 and F2. Abnormal larval and juvenile behavior was observed in the F1 generation, but not in the F2. PFHxA juvenile dietary exposure induced subtle and multigenerational behavior effects that warrant further investigation of this and other alternative short-chain PFAS.

Thermal processing reduces PFAS concentrations in blue food - A systematic review and meta-analysis

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous in the environment and often ingested with food. PFAS exposure in people can have detrimental health consequences. Therefore, reducing PFAS burdens in food items is of great importance to public health. Here, we investigated whether cooking reduces PFAS concentrations in animal-derived food products by synthesizing experimental studies. Further, we examined the moderating effects of the following five variables: cooking time, liquid/animal tissue ratio, cooking temperature, carbon chain length of PFAS and the cooking category (oil-based, water-based & no-liquid cooking). In our systematic review searches, we obtained 512 effect sizes (relative differences in PFAS concentration between raw and cooked samples) from 10 relevant studies. These studies exclusively explored changes in PFAS concentrations in cooked seafood and freshwater fish. Our multilevel-meta-analysis has revealed that, on average, cooking reduced PFAS concentrations by 29%, although heterogeneity among effect sizes was very high (I² = 94.65%). Our five moderators cumulatively explained 49% of the observed heterogeneity. Specifically, an increase in cooking time and liquid/animal tissue ratio, as well as shorter carbon chain length of PFAS (when cooked with oil) were associated with significant reductions in PFAS concentrations. The effects of different ways of cooking depended on the other moderators, while the effect of cooking temperature itself was not significant. Overall, cooking can reduce PFAS concentrations in blue food (seafood and freshwater fish). However, it is important to note that complete PFAS elimination requires unrealistically long cooking times and large liquid/animal tissue ratios. Currently, literature on the impact of cooking of terrestrial animal produce on PFAS concentrations is lacking, which limits the inference and generalisation of our meta-analysis. However, our work represents the first step towards developing guidelines to reduce PFAS in food via cooking exclusively with common kitchen items and techniques.

Associations between prenatal exposure to perfluoroalkyl substances, hypomethylation of MEST imprinted gene and birth outcomes

Prenatal perfluoroalkyl substance (PFAS) exposure has been linked to adverse birth outcomes, but the underlying mechanism has yet to be elucidated. DNA methylation changes in mesoderm-specific transcript (MEST) imprinted gene may be a mechanism of the prenatal exposure effects of PFASs on fetal growth. The aim was to investigate the prenatal PFASs exposure effects on DNA methylation changes in MEST imprinted gene involved in fetal growth. Among 486 mother-infant pairs from the Taiwan Birth Panel Study, PFASs and DNA methylation levels at 5 CpG sites of MEST promoter region were measured in cord blood. Univariable and multivariable linear regressions were performed to estimate the associations between prenatal PFAS exposure, MEST DNA methylation levels, and child birth outcomes. Mediation analysis was performed to examine the potential pathway of MEST methylation between PFASs and birth outcomes. We found that higher prenatal perfluorooctyl sulfonate (PFOS) exposure was significantly associated with lower methylation levels at 5 CpG sites of MEST promoter region (an adjusted β range: -1.56, -2.22). Significant negative associations were also found between MEST methylation levels and child birth weight. Furthermore, the associations between PFOS and perfluorooctanoic acid (PFOA) exposure and MEST methylation levels were more profound in girls than in boys. The mediated effect of average MEST methylation level between PFOS exposure and birth weight was 18.3 (95% CI = 2.1, 40.2; p = 0.014). The direct effect of PFOS exposure to birth weight independent to average MEST methylation level was -93.2 (95% CI = -170.5, -17.8; p = 0.018). In conclusion, our results suggest that prenatal PFAS exposure, especially PFOS, is associated with lower methylation levels at MEST promoter region, which not only leverages the role of imprinted gene in ensuring the integrity of fetal growth but also provides a potential mechanism for evaluating the prenatal exposure effect.

Association between serum per- and polyfluoroalkyl substances and thrombograms in young and middle-aged Taiwanese populations

PURPOSE

Per- and polyfluoroalkyl substances (PFAS) are a class of man-made chemicals used in many products. Recent in vitro and epidemiological reports have found that PFAS exposure can modify the function of platelets. Platelet size has been shown to affect platelet activity, and thrombograms are a simple method of indirect assessment of platelet function. However, there has been no large-scale research investigating the association between PFAS levels and complete thrombograms in humans.

APPROACH AND RESULTS

In the current cross-sectional study, we enrolled 1779 Taiwanese subjects (aged between 12 and 63 years) to study the associations between serum PFAS concentrations and thrombograms. There were 1175 men and 604 women with a mean age of 34.5 years. When all four PFAS were fitted by the multiple linear models at the same time, platelet counts decreased significantly with increasing quartiles of perfluorooctanoate acid (PFOA) and perfluorooctane sulfonate (PFOS), while platelet distribution width (PDW), mean platelet volume (MPV), and platelet-large cell ratio (PLCR) also increased significantly with increasing quartiles of PFOS. The mean platelet count was the lowest (264.02 k/µL [95% CI 256.00-272.04]; P < 0.001) when both PFOA and PFOS concentrations were above the 50th percentile.

CONCLUSIONS

We report that serum PFAS levels were correlated with thrombograms. If the association is etiologic, PFOA/PFOS may decrease the number of platelets, while PFOS may also increase the variation and the average size of platelets in the subjects of the study. Interestingly, PFOA and PFOS may have synergistic effects on the decrease in platelet counts. Further research is needed to study the effect of PFAS on platelets in humans.

Plasmonic Superstructure Arrays Fabricated by Laser Near-Field Reduction for Wide-Range SERS Analysis of Fluorescent Materials

Surface-enhanced Raman scattering (SERS) enables trace-detection for biosensing and environmental monitoring. Optimized enhancement of SERS can be achieved when the energy of the localized surface plasmon resonance (LSPR) is close to the energy of the Raman excitation wavelength. The LSPR can be tuned using a plasmonic superstructure array with controlled periods. In this paper, we develop a new technique based on laser near-field reduction to fabricate a superstructure array, which provides distinct features in the formation of periodic structures with hollow nanoclusters and flexible control of the LSPR in fewer steps than current techniques. Fabrication involves irradiation of a continuous wave laser or femtosecond laser onto a monolayer of self-assembled silica microspheres to grow silver nanoparticles along the silica microsphere surfaces by laser near-field reduction. The LSPR of superstructure array can be flexibly tuned to match the Raman excitation wavelengths from the visible to the infrared regions using different diameters of silica microspheres. The unique nanostructure formed can contribute to an increase in the sensitivity of SERS sensing. The fabricated superstructure array thus offers superior characteristics for the quantitative analysis of fluorescent perfluorooctanoic acid with a wide detection range from 11 ppb to 400 ppm.

Assessment of per- and polyfluoroalkyl substances in Biscayne Bay surface waters and tap waters from South Florida

Per- and polyfluoroalkyl substances (PFAS) are persistent anthropogenic pollutants present in many environmental media worldwide due to their extensive uses in many industrial and commercial products combined with their high thermal and chemical stabilities. Its ubiquitous presence in surface and drinking water supply and significant adverse health effects observed in wildlife and humans, associated with its bioaccumulation potential, pose big concerns. In this study, we have developed and validated a semi-automated solid phase extraction (SPE) followed by liquid chromatography-mass spectrometry (LC-MS/MS) for the determination of legacy and emerging short-chain PFAS substitutes in surface and tap water at low parts-per-trillion (ppt) levels in South Florida environments. Surface waters from Biscayne Bay and adjacent canals (n = 15) and tap waters from different counties (Miami-Dade, Broward, and Palm Beach County) (n = 21) were collected between October 2020 (wet season) and February 2021 (dry season). Total PFAS concentrations up to 242 ng L^-1 (average of 168 ng L^-1) were found in tap water from Grapeland Heights, which is the closest location to the Miami international airport that was sampled. The highest average total PFAS level of 106 ng L^-1 was observed in surface water from the Biscayne Canal C-8 for the wet and dry season. In general, average total PFAS was higher in tap water (86.3 ng L^-1) than in surface waters (46.3 ng L^-1), whereas the most predominant and frequently detected PFAS were PFBA, PFBS, PFPeA, PFHxA, PFHxS, PFOA and PFOS. PFAS levels found could represent a high human health risk, and ecological risk based on PFOS levels above recommended thresholds are also noted. Such knowledge on PFAS occurrence, distribution and sources in South Florida will provide essential information for local and regional regulatory agencies related to water quality, further facilitating the development of guidelines and procedures for PFAS pollution control and reduction in Florida.

A sensitive method for the detection of legacy and emerging per- and polyfluorinated alkyl substances (PFAS) in dairy milk

There is widespread contamination by per- and polyfluoroalkyl substances (PFAS) across the globe, with adverse effects on human and environmental health. For human exposure, drinking water and dietary exposure have been recognized as important PFAS exposure pathway for the general population. Several documented cases of dairy milk contamination by PFAS have raised concerns over this exposure pathway in general. A sensitive method for determination of 27 PFAS in milk was hence modified and applied on raw and processed milk samples from 13 farms across the United States (U.S.). A combination of acid and basic extraction method and ENVI-Carb clean-up achieved recoveries of targeted PFAS between 70 and 141%. The method detection limits (MDL) ranged from 0.8 to 22 ng/L (for 26 PFAS) and 144 ng/L for perfluorobutanoic acid (PFBA). The uniqueness of this method is considered in the targeted screening of a broad range of legacy PFAS, as well as perfluorinated sulfonamide species and fluorotelomer sulfonates. No legacy PFAS were detected in 13 milk samples from regions of concern given local use of biosolids or proximity to fire training areas. Overall, then, the uptake of perfluoroalkyl acids (PFAA) from dairy milk in the U.S. is considered low.

Occurrence of selected per- and polyfluorinated alkyl substances (PFASs) in food available on the European market - A review on levels and human exposure assessment

Per- and polyfluorinated alkyl substances (PFASs) are considered emerging persistent organic pollutants, which are chemically, thermally, and biologically stable, or degrade to persistent end products. Dietary intake is considered as one of the main human exposure pathways of these chemicals and, having entered the human body, PFASs are not metabolised and accumulate in tissues, while their toxicological properties may cause various health problems. Several studies on the occurrence of PFASs in various food types have been conducted, including the assessment of dietary exposure. The most important sources were fish, meat, eggs, fruits, and vegetables. Fruits and vegetables recently showed relatively high levels of PFASs, and have become a more significant source of PFASs than meat. In 2020, the European Food Safety Authority (EFSA) published an opinion, setting the tolerable weekly intake (TWI) of 4.4 ng kg-1 b.w. for the sum of perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorohexanesulphonic acid (PFHxS), and perfluorooctanesulphonic acid (PFOS). The emphasis in this paper is on the systematization of available information on the distribution of PFASs and their levels in different food, with a special interest in data from the Europe. The current legislation and estimated dietary intakes by the general population are described. While the available information on tolerably daily intakes estimated in a number of European countries often exceeds the newly established EFSA TWI, a critical evaluation of performance characteristics of the reviewed analytical methodologies revealed the insufficient sensitivity of quantification procedures for accurate risk assessment according to the guidelines proposed by EFSA.

Association between the total plasma isomers of per- and polyfluoroalkyl substances and erythrograms in young and middle-aged Taiwanese populations

PURPOSE

Per- and polyfluoroalkyl substances (PFAS) are human-made chemicals used in daily use products. Recent studies have shown that different perfluorooctanoic acid (PFOA) and/or perfluorooctane sulfonate (PFOS) isomers may have different biological effects. In vitro studies have also reported that PFAS exposure can alter the structure of hemoglobin (Hb). In epidemiology, however, few studies have investigated the relationship between PFAS exposure and erythrocytes. Additionally, the correlation between PFOA/PFOS isomers and full erythrograms has never been explored.

APPROACH AND RESULTS

In cohorts comprising young and middle-aged Taiwanese populations, we enrolled 1483 participants (aged between 12 and 63 years) to analyze the correlations between the plasma levels of PFOA/PFOS isomers and whole-blood erythrograms. The study comprised 868 men and 615 women with a mean age of 31.2 years. When all PFOA/PFOS isomers were entered into the multiple linear regression model, the linear PFOA (L-PFOA) levels were positively correlated with the Hb, hematocrit (HCT), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) levels while the branched PFOS (B-PFOS) levels were positively associated with the Hb, HCT, and mean corpuscular hemoglobin concentration (MCHC). The mean value of Hb was the highest (14.66 mg/dL (95% CI =14.52-14.80); P for trend <0.001) when both the L-PFOA and B-PFOS levels were above the 50th percentile.

CONCLUSIONS

The results imply that PFOA/PFOS isomers may increase the weight and volume of Hb/RBC and that L-PFOA/B-PFOS may have an additive effect on the Hb levels. However, it is also possible PFAS detected at a higher concentration may due to its binding to higher levels of Hb. Further studies are needed to investigate the effects of PFOA/PFOS isomers on RBCs in humans.

Per- and polyfluoroalkyl substances (PFASs) in the soil-plant system: Sorption, root uptake, and translocation

Per- and polyfluoroalkyl substances (PFASs) are ubiquitous in the environment but pose potential risks to ecosystems and human health. The soil-plant system plays an important role in the bioaccumulation of PFASs. Because most PFASs in the natural environment are anionic and amphiphilic (both lipophilic and hydrophilic), their sorption and accumulation behaviors differ from those of neutral organic and common ionic compounds. In this review, we discuss processes affecting the availability of PFASs in soil after analyzing the potential mechanisms underlying the sorption and uptake of PFASs in the soil-plant system. We also summarize the current knowledge on root uptake and translocation of PFASs in plants. We found that the root concentration factor of PFASs for plants grown in soil was not significantly correlated with hydrophobicity, whereas the translocation factor was significantly and negatively correlated with PFAS hydrophobicity regardless of whether plants were grown hydroponically or in soil. Further research on the cationic, neutral, and zwitterionic forms of diverse PFASs is urgently needed to comprehensively understand the environmental fates of PFASs in the soil-plant system. Additional research directions are suggested, including the development of more accurate models and techniques to evaluate the bioavailability of PFASs, the effects of root exudates and rhizosphere microbiota on the bioavailability and plant uptake of PFASs, and the roles of different plant organelles, lipids, and proteins in the accumulation of PFASs by plants.

Correlates of Persistent Endocrine-Disrupting Chemical Mixtures among Reproductive-Aged Black Women

Black women are exposed to multiple endocrine-disrupting chemicals (EDCs), but few studies have examined their profiles of exposure to EDC mixtures. We identified biomarker profiles and correlates of exposure to EDC mixtures in a cross-sectional analysis of data from a prospective cohort study of 749 Black women aged 23-35 years. We quantified plasma concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs), and per- and polyfluoroalkyl substances (PFAS) in nonfasting samples collected at baseline. Demographic, behavioral, dietary, and reproductive covariates were also collected at baseline. We used k-means clustering and principal component analysis (PCA) to describe concentration profiles of EDC mixtures (17 PCBs, 6 PBDEs, 4 OCPs, 6 PFAS), followed by multinomial logistic and multivariable linear regression to estimate mean differences in PCA scores (β) and odds ratios (ORs) of cluster membership with their respective 95% confidence intervals (CIs). Older age (per 1 year increase: β = 0.47, CI = 0.39, 0.54; OR = 1.27, CI = 1.20, 1.35), lower body mass index (per 1 kg/m² increase: β = -0.14, CI = -0.17, -0.12; OR = 0.91, CI = 0.89, 0.94), and current smoking (≥10 cigarettes/day vs never smokers: β = 1.37, CI = 0.20, 2.55; OR = 2.63, CI = 1.07, 6.50) were associated with profiles characterized by higher concentrations of all EDCs. Other behaviors and traits, including dietary factors and years since last birth, were also associated with EDC mixtures.

Accumulation of PFAS by livestock - determination of transfer factors from water to serum for cattle and sheep in Australia

In this study accumulation has been determined of several per- and polyfluoroalkyl substances (PFAS) from ingested water to steady state serum concentration for adult beef cattle and sheep raised on a hobby farm impacted by PFAS contamination. PFAS concentrations in stock water were stable for more than a year, they were non-measurable in grass but present at very low levels in soil which equated to just 1% of the intake from water. Prior to quantifying PFAS in cattle serum there had been no breeding for 18 months. Although there were high concentrations of several PFAS in the water, only perfluorooctane sulphonate (PFOS) and perfluorohexane sulphonate (PFHxS) were in cattle serum in appreciable amounts; perfluoroheptane sulphonate (PFHpS), perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) were much lower. Transfer factors (TFs) for cattle were calculated by dividing steady state serum concentration (ng PFAS/mL) by water concentration (µg PFAS/L). Average and upper estimate TF values for cattle were calculated; the former were 140 (total PFOS, i.e. tPFOS), 130 (PFHpS), 65 (PFHxS), 170 (PFNA), and 120 (PFDA). Previous investigation campaigns at the farm provided relative steady state serum PFAS concentrations for sheep and cattle that allowed adjustment of the cattle TFs. The resulting average estimate TFs for ewes (non-pregnant and not lactating) were 20 (tPFOS) and 30 (PFHxS), other PFAS were not measurable in sheep serum. Discussion on using these TFs in human health risk assessments is provided. With certain assumptions/caveats the TFs allow estimations of PFAS steady state serum concentrations for use in preliminary human health risk assessments (HHRAs) when only PFAS in stock water is known.

Are there risks induced by novel and legacy poly- and perfluoroalkyl substances in coastal aquaculture base in South China?

Perfluoroalkyl substances (PFASs) have raised great attention as emerging contaminants due to their persistent and bioaccumulative characteristics. Following the global actions to limit perfluorooctanesulfonic acid (PFOS) and its salts, chlorinated polyfluorinated ether sulfonate (F-53B), as an alternative perfluorochemical, has been a focus during this period. In this study, PFASs in coastal seawater, sediment, and seaweed from the significant aquaculture bases of Porphyra haitanensis in the southeast of China were investigated. Their bioaccumulation and ecological risk were elucidated and associated human exposures to PFASs with consumption of aquatic products for rural and urban groups were calculated. The total PFASs levels in seawater and sediment were 21.52-241.86 ng/L and 4.55-26.54 ng/g·dw, respectively. F-53B was found frequently and has relative high concentration in seawater (ND-2.13 ng/L). The Porphyra haitanensis and Siganus fuscescens were also analyzed, with PFASs concentrations ranging from 10.45 to 29.98 ng/g·dw and 7.17 to 25.43 ng/g·dw, respectively. The total logarithm BAF of F-53B and PFOS in two kinds of detected seafoods were within 0-2.94 and 2.01-3.25, these values did not vary in different sites. The estimated daily intake (EDI) of PFASs through aquatic products consumption in rural and urban residents were 0.03-26.50 ng/kg bw/day and 0.17-37.01 ng/kg bw/day, respectively, based on the Dietary Guidelines for Chinese residents. The total EDI of PFASs via Porphyra haitanensis and Siganus fuscescens in different groups were significantly lower than the suggested tolerable daily intake (PFOS, 150 ng/kg bw/day; PFOA, 1500 ng/kg bw/day), which indicates that PFASs did not induce health risks to the residents living around these aquaculture bases.

Yale School of Public Health Symposium: An overview of the challenges and opportunities associated with per- and polyfluoroalkyl substances (PFAS)

On December 13, 2019, the Yale School of Public Health hosted a symposium titled "Per- and Polyfluoroalkyl Substances (PFAS): Challenges and Opportunities" in New Haven, Connecticut. The meeting focused on the current state of the science on these chemicals, highlighted the challenges unique to PFAS, and explored promising opportunities for addressing them. It brought together participants from Yale University, the National Institute of Environmental Health Sciences, the University of Massachusetts Amherst, the University of Connecticut, the Connecticut Agricultural Experiment Station, the Connecticut Departments of Public Health and Energy and Environmental Protection, and the public and private sectors. Presentations during the symposium centered around several primary themes. The first reviewed the current state of the science on the health effects associated with PFAS exposure and noted key areas that warranted future research. As research in this field relies on specialized laboratory analyses, the second theme considered commercially available methods for PFAS analysis as well as several emerging analytical approaches that support health studies and facilitate the investigation of a broader range of PFAS. Since mitigation of PFAS exposure requires prevention and cleanup of contamination, the third theme highlighted new nanotechnology-enabled PFAS remediation technologies and explored the potential of green chemistry to develop safer alternatives to PFAS. The fourth theme covered collaborative efforts to assess the vulnerability of in-state private wells and small public water supplies to PFAS contamination by adjacent landfills, and the fifth focused on strategies that promote successful community engagement. This symposium supported a unique interdisciplinary coalition established during the development of Connecticut's PFAS Action Plan, and discussions occurring throughout the symposium revealed opportunities for collaborations among Connecticut scientists, state and local officials, and community advocates. In doing so, it bolstered the State of Connecticut's efforts to implement the ambitious initiatives that its PFAS Action Plan recommends.

Presence of Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) in Food Contact Materials (FCM) and Its Migration to Food

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are synthetic chemical compounds widely used in different industry fields including food contact materials (FCM), providing resistance to fat and humidity, and non-stick properties. PFAS enter into the food chain directly from the intake of contaminated food or indirectly from the migration of the FCM into the food. This exposure published in different research highlights a public health concern. Therefore, it is necessary to perform analysis of the content of different FCM and evaluate the migration from the FCM under normal conditions of use and storage. This bibliographical review proves that different perfluoroalkyl and polyfluoroalkyl compounds are detected in fast food packaging, microwave popcorn bags, and frying pans, among others. Furthermore, it shows the conditions or factors that favor the migration of the PFAS from the FCM into the food.

Per- and polyfluoroalkyl substances (PFAS) in livestock and game species: A review

Per- and polyfluoroalkyl substances (PFAS) are synthetic, organic chemicals that resist environmental breakdown. The properties that made PFAS into an industrial success also led to their persistence and bioaccumulation. As PFAS were widely used for many decades their presence is evident globally, and their persistence and potential for toxicity create concern for human, animal and environmental health. Following the precautionary principle, a reduction in human exposure is generally recommended. The most significant source of human exposure to PFAS is dietary intake (food and water) with additional exposure via dust. As PFAS concentrations have been more frequently studied in aquatic food sources, there is less understanding of exposure via terrestrial animals. To further define human exposure via animal products, it is necessary to determine PFAS concentrations and persistence in terrestrial livestock and game species. Studies assessing ambient concentrations of PFAS have noted that, aside from point sources of contamination, there is generally low input of PFAS into terrestrial agricultural food chains. However, livestock and game species may be exposed to PFAS via contaminated water, soil, substrate, air or food, and the contribution of these exposures to PFAS concentrations in food products is less well studied. This review focuses on perfluoroalkyl substances (PFAAs) and compiles information from terrestrial livestock and game species as a source of dietary exposure in humans, and discusses toxicokinetics and health effects in animals, while identifying future focus areas. Publications describing the transfer of PFAAs to farmed and hunted animals are scarce, and demonstrate large variability in distribution and elimination. We outline several relatively small, short-term studies in cattle, sheep, pigs and poultry. While negative effects have not been noted, the poultry investigations were the only studies to explicitly assess health effects. Comparative information is presented on PFAA concentrations in livestock products and edible tissues of game animals.

Determination of perfluorooctane sulphonate and perfluorooctanoic acid in seafood and water from Map Ta Phut Industrial Estate area, Thailand

This initial study aimed to determine the concentrations of perfluorooctane sulphonate (PFOS) and perfluorooctanoic acid (PFOA) in seafood, bottled drinking water, and surface and tap water collected from Map Ta Phut Industrial Estate in Rayong province, Thailand. Samples were collected during dry (January) and wet (June) seasons, 2019. The perfluorinated compounds were cleaned up by solid phase extraction and analysed by ultra-performance liquid chromatography-tandem mass spectrometry with stable isotopic labelled internal standards (13C8-PFOS and 13C8-PFOA). This study reports concentrations of PFOS and PFOA in seafood at levels between 29-6724 and <48-421 ng/kg wet weight, respectively. Surface water samples from rivers and the coastal sea had PFOS and PFOA between 0.60-465.65 and <0.25-59.29 ng/L, respectively. Contamination of PFOS and PFOA in bottled drinking water (<0.125-0.454 and <0.25-0.621 ng/L, respectively) did not exceed the USEPA standard of 70 ng/L. Concentrations of PFOS and PFOA in seafood and water samples between seasons did not show any definite trend. Seafood dietary assessments of PFOS exposure in the seafood eater population raised a health concern, as the exposure exceeded the latest EFSA tolerable weekly intake value for PFAS mixtures (4.4 ng/kg body weight/week). Therefore, environmental and food samples from Map Ta Phut area should be closely monitored to ensure the safety of people living in and around this area.

Maternal exposure to environmental endocrine disruptors during pregnancy is associated with pediatric germ cell tumors

This study aimed to evaluate the efficacy of interventions to reduce patient misidentification incidents classified as level 2 and over (adverse events occurred for patients) with the step-by-step problem-solving method. All incidents related to patient misidentification were selected, and relevant information was collected from the original electronic incident reports. We then conducted an eight-step problem-solving process with the aim of reducing patient misclassification and improving patient safety. Step 1: the number of misidentification-related incident reports and the percentage of these reports in the total incident reports increased each year. Step 2: the most frequent misidentification type was sample collection tubes, followed by drug administration and hospital meals. Step 3: we set a target of an 20% decrease in patient misidentification cases classified as level 2 or over compared with the previous year, and established this as a hospital priority. Step 4: we found that discrepancies in patient identification procedures were the most important causes of misidentification. Step 5: we standardized the patient identification process to achieve an 10% reduction in misidentification. Step 6: we disseminated instructional videos to all staff members. Step 7: we confirmed there was an 18% reduction in level 2 and over patient misidentification compared with the previous year. Step 8: we intend to make additional effort to decrease misidentification of patients by a further 10%. Level 2 and over patient misidentification can be reduced by a patient identification policy using a step-by-step problem-solving procedure. This study aimed to evaluate the efficacy of interventions to reduce patient misidentification incidents with step-by-step problem-solving method. Continued seamless efforts to eliminate patient misidentification are mandatory for this activity.

Early-life perfluorooctanoic acid exposure induces obesity in male offspring and the intervention role of chlorogenic acid

Perfluorooctanoic acid (PFOA) is an emerging organic pollutant (EOP) hazardous to human health. Effects of maternal PFOA exposure on offspring as well as the underlying mechanisms remain unclear. In this study, ICR mouse models of gestational low PFOA exposure (0.05 mg/kg/day) were established to investigate the roles on metabolic disorders of offspring. Body weight, body composition, hepatic lipid levels, transcriptome and metabolome were analyzed. Expression of genes related to lipid metabolism, inflammasome formation and gut barrier integrity were measured. Furthermore, oral administration of chlorogenic acid (CGA) (100 mg/kg/day) was performed to observe the rescue effect on lipid disorders caused by PFOA exposure. Our findings demonstrated that gestational exposure to PFOA resulted in obesity, hepatic inflammation, disorders of lipid metabolism, and disruption of gut barrier integrity in male offspring. Notably, these adverse effects were attenuated by CGA supplementation. These data suggested that PFOA exposure during early life stage induced potential risks for later onset of obesity and metabolic disorder which could be ameliorated by CGA treatment.

The defluorination of perfluorooctanoic acid by different vacuum ultraviolet systems in the solution

Perfluorooctanoic acid (PFOA) is one kind of persistent organic pollutants that is often detected in water. In recent years, the effective degradation technologies of PFOA have attracted widespread attentions. Thus, in this study, the defluorination efficiency of PFOA in different systems (i.e., ultraviolet (UV), vacuum ultraviolet (VUV), vacuum ultraviolet/persulfate (VUV/PS) and vacuum ultraviolet/residual chlorine (VUV/RC)) was evaluated. Moreover, the different impact factors (i.e., the initial concentrations of persulfate and PFOA, temperature, anions, and initial pH values) on PFOA degradation by VUV/PS system were investigated. The results showed that VUV system was more effective than UV system for PFOA defluorination. VUV system combined with persulfate would further enhance the defluorination efficiency while residual chlorine would decrease it. In VUV/PS system, the defluorination efficiency of PFOA was the best as the molar ratio of PFOA and persulfate at 1:60. Moreover, higher temperature, lower initial PFOA concentration, and acid condition were favorable for the defluorination of PFOA. Under the different influence factors, the defluorination efficiency of PFOA fitted well to the first-order reaction kinetic model. When the temperature was range from 20°C to 40°C, the value of activation energy was 8.73 kJ/mol. Besides, the inhibition effect of three kinds of anions on PFOA defluorination followed the order: NO 3 -  > Cl^-  >  CO 3 2 - . PRACTITIONER POINTS: The defluorination efficiency of perfluorooctanoic acid (PFOA) in water by different VUV systems was compared. VUV system is more effective than UV system for PFOA defluorination. Persulfate will enhance the defluorination efficiency by VUV system. Hypochlorite will decrease the defluorination efficiency by VUV system.

Determination and assessment of human dietary intake of per and polyfluoroalkyl substances in retail dairy milk and infant formula from South Africa

Dairy milk and infant formula play important roles in the diet of adolescents, adults and infants, respectively, in the South African population. However, data on the occurrence of legacy and emerging contaminants such as PFAS in these important food sources is lacking. In this study, the concentration of fifteen PFAS were measured in 23 pooled retail dairy milk and 7 pooled infant formulas by means of an ultrahigh performance liquid chromatography tandem mass spectrometric method. The concentrations of Σ₁₅PFAS ranged from 0.08-15.51 ng mL^-1 and 0.42-5.74 ng mL^-1 in dairy milk and infant formulas, respectively. PFBA, PFPeA, PFuDA, PFTrDA and PFDoA were the most prevalent PFAS in both matrices with detection frequency > 96%. Highest PFAS concentrations of 2.02 ng ml^-1 and 2.76 ng ml^-1 were recorded for PFDoA in infant formulas and dairy milk, respectively. The concentrations of legacy PFAS -PFOA and PFOS, shows resemblance with global data, however, elevated concentrations of long chain C₉ - C₁₄ PFAS were observed in this study. Though, higher concentrations of PFAS were measured in full cream dairy milk, no statistical significant difference (P = 0.546) was observed for the various classes of dairy milk. The EDI of Σ₁₅PFAS through infant formulas were 184.92, 329.47 and 166 ngkg^-1BWday^-1 for partially breastfed, exclusively formula fed and older infants, respectively. Similarly, the EDI of PFAS through dairy milk for toddlers, adolescents, female and male adults for the rural population were 14.17, 1.09, 2.59 and 3.16 ngkg^-1BWday^-1 respectively while they were 20.41, 3.84, 4.13 and 4.26 ngkg^-1BWday^-1 respectively in the urban population. Although, the EDI of PFAS through the consumption of infant formulas and dairy milk are lower than the daily tolerable limits, the relative importance of long-term exposure and the cumulative effects of multiple exposure pathways cannot be overemphasized.

Characteristics, pollution patterns and risks of Perfluoroalkyl substances in drinking water sources of Taiwan

Perfluoroalkyl substances (PFASs) are found globally in the environment, but for Taiwan there is a lack of studies on PFAS occurrence, source apportionment, and health risks in drinking water sources. We collected surface water samples from the Baoshan Reservoir of Taiwan and used Positive Matrix Factorization to attribute PFAS contaminants to possible sources. The health index (HI) was used to evaluate the health risk, which was then compared to various international advisory level guidelines. PFOA and PFOS were found to be the most predominant compounds, with concentrations averaging 20.2 ng/L and 16.7 ng/L, respectively. The joint contribution of domestic and commercial waste totaled 61.2% as the predominant source of pollution, followed by urban activities as a secondary source contributing 38.8%. Using the USEPA reference dose, a health risk analysis of Baoshan Reservoir drinking water did not reflect a formal high health risk (HI < 1.0), however potential risks to human health may be present since the sum of PFOA and PFOS (130 ng/L) exceeded the USEPA Lifetime Health Advisory level (70 ng/L). This investigation provides information and reference points for further reviews of PFAS presence in public water supplies.

Internal distribution and fate of persistent organic contaminants (PCDD/Fs, DL-PCBs, HBCDs, TBBPA, and PFASs) in a Bos Taurus

While terrestrial organisms such as livestock are consumed regularly, studies of internal distribution and bioaccumulation of persistent organic pollutants (POPs) have been focused more on aquatic organisms. In this study, we have assessed the internal distribution and fate of legacy (PCDD/Fs and PCBs) and emerging POPs (HBCDs and PFASs), and TBBPA in 42 tissues of a Bos Taurus. PCDD/Fs, DL-PCBs, and HBCDs were found 3, 4, and 4-fold higher in the lipid-rich organs (subcutaneous fat, visceral fat, large intestine) compared to the remaining organs and muscles, owing to their hydrophobic properties. The TBBPA concentration in the excrement was 36-fold higher compared to the average tissues, suggesting a short internal half-life of TBBPA. Among PFASs, PFUnDA displayed 98% contribution from all ionic PFASs in the tissues due to its strong binding affinity, high exposure via feed and water, and increasing emergence of PFUnDA and its precursors in the Southeast Asian countries. While our study suggests that, at the moment, there is no significant health risks to the general Korean population, the future changes in environmental exposure as well as the internal dynamics and fate of various POPs species should be kept in mind when consuming various parts of livestock.

Perfluoroalkyl Substances in U.S. market basket fish and shellfish

Over the past two decades the class of per- and polyfluoroalkyl substances (PFAS) has emerged as a widespread contaminant in environmental media globally. As awareness and understanding of its prevalence, persistence, and potential health risks grows, so have concerns about human exposure. While drinking water has received substantial attention, dietary intakes have also been reported to contribute significantly to total exposure, with fish consumption in particular. Most studies of U.S. fish have targeted sport fish from areas of known or suspected contamination. This study was undertaken to improve data on PFAS levels in the U.S. commercial seafood supply. A total of 70 samples of finfish and shellfish were purchased at U.S. grocery stores and fish markets and analyzed for 26 PFAS compounds. The samples included a range of marine and freshwater species from four regions of the U.S. and seven countries with significant imports to the U.S. Up to ten PFAS were detected in 21 samples, with PFOS the predominant compound. There were no detections in the remaining 49 samples (detection limits of approximately 0.4-0.5 ppb). Total PFAS concentrations in most samples were single digit or sub-ppb levels. The exception was commercial finfish from the Great Lakes area, for which higher levels (up to 22 ppb) were observed in whitefish, walleye, and yellow perch fillet. Study findings suggest PFAS is present at low or non-detect levels in the U.S. commercial seafood supply and exposure is low for consumers of market basket fish and shellfish.

Per- and polyfluoroalkyl substances (PFASs) in blood of captive Siberian tigers in China: Occurrence and associations with biochemical parameters

Per- and polyfluoroalkyl substances (PFASs) have been ubiquitously detected in the environment and marine animals. However, little is known about these substances and their associations with health parameters in wild terrestrial mammals. In this study, we determined PFAS levels and distribution in the blood of captive Siberian tigers in Harbin, China, and evaluated potential exposure pathways by daily intake. In addition, for the first time, we explored the associations between serum PFAS concentrations and clinical parameters. Results showed that perfluorooctanoate (PFOA) was the dominant PFAS compound in blood (accounting for 64%), followed by perfluorooctanesulfonate (PFOS). In addition, 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA) concentrations were also detected in blood and dietary food. Furthermore, significant positive age relationships were observed for levels of perfluoroheptanoate (PFHpA), PFOA, PFOS, and 6:2 Cl-PFESA in the blood of female tigers. Results showed that PFOA and PFOS in dietary food accounted for over 70% of total daily intake of PFASs, indicating that meat consumption is a predominant exposure pathway in tigers. We also found positive associations between higher exposure to PFASs (including PFOA, PFOS, and 6:2 Cl-PFESA) and elevated serum levels of alanine transaminase (ALT), a marker of liver damage. Thus, comprehensive health assessments of PFAS burdens in wildlife are needed.

Association between exposure to perfluoroalkyl substances and metabolic syndrome and related outcomes among older residents living near a Science Park in Taiwan

Perfluoroalkyl substances (PFASs) are an emerging class of artificial environmental chemicals that have multiple potentially harmful effects on health. The largest Science Park in Taiwan discharges wastewater containing PFASs into the Keya River, and a high concentration of PFASs has been found in this river and its aquatic creatures. We conducted a cross-sectional study from 2016 to 2017 of 397 subjects aged 55-75 years living near the river and evaluated the association of PFASs with metabolic syndrome and related outcomes. The results indicated that perfluorooctane sulfonate (PFOS) levels were positively associated with serum low-density lipoprotein (LDL) levels (P for trend = 0.03) and that perfluorononanoic acid (PFNA) and PFOS levels were positively correlated with uric acid levels (P for trend = 0.03 and 0.03). Perfluorodecanoic acid (PFDA) and perfluoroundecanoic acid (PFUnDA) levels were negatively associated with serum triglyceride levels (P for trend = 0.014 and < 0.01). After excluding lipid-lowering drug users, the association between certain PFAS levels and the LDL level was significantly enhanced, but the downward trends of serum triglyceride levels were weakened. When stratified by sex, PFNA (P for trend <0.01), perfluorohexanesulfonate (PFHxS) (P for trend <0.01), and PFOS (P for trend <0.01) showed positive associations with the uric acid level only among males. In conclusion, our results showed that associations were consistently null between PFASs and metabolic syndrome. PFAS levels were associated with serum lipids, and lipid-lowering drugs may interfere with this relationship. Certain PFASs were found to be positively associated with uric acid levels, especially in males. Further studies are warranted to clarify the causal relationships.

Risk to human health related to the presence of perfluoroalkyl substances in food

The European Commission asked EFSA for a scientific evaluation on the risks to human health related to the presence of perfluoroalkyl substances (PFASs) in food. Based on several similar effects in animals, toxicokinetics and observed concentrations in human blood, the CONTAM Panel decided to perform the assessment for the sum of four PFASs: PFOA, PFNA, PFHxS and PFOS. These made up half of the lower bound (LB) exposure to those PFASs with available occurrence data, the remaining contribution being primarily from PFASs with short half-lives. Equal potencies were assumed for the four PFASs included in the assessment. The mean LB exposure in adolescents and adult age groups ranged from 3 to 22, the 95th percentile from 9 to 70 ng/kg body weight (bw) per week. Toddlers and 'other children' showed a twofold higher exposure. Upper bound exposure was 4- to 49-fold higher than LB levels, but the latter were considered more reliable. 'Fish meat', 'Fruit and fruit products' and 'Eggs and egg products' contributed most to the exposure. Based on available studies in animals and humans, effects on the immune system were considered the most critical for the risk assessment. From a human study, a lowest BMDL 10 of 17.5 ng/mL for the sum of the four PFASs in serum was identified for 1-year-old children. Using PBPK modelling, this serum level of 17.5 ng/mL in children was estimated to correspond to long-term maternal exposure of 0.63 ng/kg bw per day. Since accumulation over time is important, a tolerable weekly intake (TWI) of 4.4 ng/kg bw per week was established. This TWI also protects against other potential adverse effects observed in humans. Based on the estimated LB exposure, but also reported serum levels, the CONTAM Panel concluded that parts of the European population exceed this TWI, which is of concern.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) and their effects on the ovary

BACKGROUND

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are found widespread in drinking water, foods, food packaging materials and other consumer products. Several PFAS have been identified as endocrine-disrupting chemicals based on their ability to interfere with normal reproductive function and hormonal signalling. Experimental models and epidemiologic studies suggest that PFAS exposures target the ovary and represent major risks for women's health.

OBJECTIVE AND RATIONALE

This review summarises human population and toxicological studies on the association between PFAS exposure and ovarian function.

SEARCH METHODS

A comprehensive review was performed by searching PubMed. Search terms included an extensive list of PFAS and health terms ranging from general keywords (e.g. ovarian, reproductive, follicle, oocyte) to specific keywords (including menarche, menstrual cycle, menopause, primary ovarian insufficiency/premature ovarian failure, steroid hormones), based on the authors' knowledge of the topic and key terms.

OUTCOMES

Clinical evidence demonstrates the presence of PFAS in follicular fluid and their ability to pass through the blood-follicle barrier. Although some studies found no evidence associating PFAS exposure with disruption in ovarian function, numerous epidemiologic studies, mostly with cross-sectional study designs, have identified associations of higher PFAS exposure with later menarche, irregular menstrual cycles, longer cycle length, earlier age of menopause and reduced levels of oestrogens and androgens. Adverse effects of PFAS on ovarian folliculogenesis and steroidogenesis have been confirmed in experimental models. Based on laboratory research findings, PFAS could diminish ovarian reserve and reduce endogenous hormone synthesis through activating peroxisome proliferator-activated receptors, disrupting gap junction intercellular communication between oocyte and granulosa cells, inducing thyroid hormone deficiency, antagonising ovarian enzyme activities involved in ovarian steroidogenesis or inhibiting kisspeptin signalling in the hypothalamus.

WIDER IMPLICATIONS

The published literature supports associations between PFAS exposure and adverse reproductive outcomes; however, the evidence remains insufficient to infer a causal relationship between PFAS exposure and ovarian disorders. Thus, more research is warranted. PFAS are of significant concern because these chemicals are ubiquitous and persistent in the environment and in humans. Moreover, susceptible groups, such as foetuses and pregnant women, may be exposed to harmful combinations of chemicals that include PFAS. However, the role environmental exposures play in reproductive disorders has received little attention by the medical community. To better understand the potential risk of PFAS on human ovarian function, additional experimental studies using PFAS doses equivalent to the exposure levels found in the general human population and mixtures of compounds are required. Prospective investigations in human populations are also warranted to ensure the temporality of PFAS exposure and health endpoints and to minimise the possibility of reverse causality.

Per- and Polyfluoroalkyl Substances and Obesity, Type 2 Diabetes and Non-alcoholic Fatty Liver Disease: A Review of Epidemiologic Findings

Per- and polyfluoroalkyl substances, a group of fluoro-surfactants widely detected in the environment, wildlife and humans, have been linked to adverse health effects. A growing body of literature has addressed their effects on obesity, diabetes and non-alcoholic fatty liver disease/ non-alcoholic steatohepatitis. This review summarizes the brief historical use and chemistry of per- and polyfluoroalkyl substances, routes of human exposure, as well as the epidemiologic evidence for associations between exposure to per- and polyfluoroalkyl substances and the development of obesity, diabetes and non-alcoholic fatty liver disease/ non-alcoholic steatohepatitis. We identified 22 studies on obesity and 32 studies on diabetes, while only 1 study was found for non-alcoholic fatty liver disease/ non-alcoholic steatohepatitis by searching PubMed for human studies. Approximately 2/3 of studies reported positive associations between per- and polyfluoroalkyl substances exposure and the prevalence of obesity and/or type 2 diabetes. Causal links between per- and polyfluoroalkyl substances and obesity, diabetes and non-alcoholic fatty liver disease/ non-alcoholic steatohepatitis, however, require further large-scale prospective cohort studies combined with mechanistic laboratory studies to better assess these associations.

Maternal exposure to environmental endocrine disruptors during pregnancy is associated with pediatric germ cell tumors

Environmental endocrine disruptors (EEDs) are natural or synthetic chemical compounds that interfere with normal endocrine function in both wildlife and humans. Previous studies have indicated that EEDs may contribute to oncogenesis. This study explores the relationship between EEDs and pediatric germ cell tumors (GCTs). A case-control study was conducted in 84 pediatric patients from 2014 to 2017, including 42 subjects with immature teratoma, yolk sac tumor, or germinoma, and 42 controls who experienced pneumonia or trauma. Serum PFASs, including PFBS, PFHpA, PFHxS, PFOA, PFOS, PFNA, PFDA, PFUA, PFOSA, and PFDoA, were measured in each subject, and their history of possible EED exposure was reviewed. Six of the 10 measured PFASs were significantly increased in the GCT group relative to the control group. With respect to lifestyle history, only PFHxS levels were statistically significantly associated with GCTs as determined by logistic regression analysis. The odds ratio for a 1 ng/L increase in PFHxS was 19.47 (95% CI: 4.20-90.26). Furthermore, in the GCT and control groups, both parental consumption of barbecued foods and hair dye use among parents were significantly correlated with elevated serum PFHxS levels (ρ = 0.383, 0.325 in the patient group and ρ = 0.370, 0.339 in the control group; p < 0.05). Our study confirmed that children with GCTs from our institute had relatively high serum levels of PFASs relative to those of tumor-free pediatric patients. Serum PFHxS levels were independently associated with germ cell tumor occurrence.

Persistent Organic Pollutants in Food: Contamination Sources, Health Effects and Detection Methods

Persistent organic pollutants (POPs) present in foods have been a major concern for food safety due to their persistence and toxic effects. To ensure food safety and protect human health from POPs, it is critical to achieve a better understanding of POP pathways into food and develop strategies to reduce human exposure. POPs could present in food in the raw stages, transferred from the environment or artificially introduced during food preparation steps. Exposure to these pollutants may cause various health problems such as endocrine disruption, cardiovascular diseases, cancers, diabetes, birth defects, and dysfunctional immune and reproductive systems. This review describes potential sources of POP food contamination, analytical approaches to measure POP levels in food and efforts to control food contamination with POPs.

Preliminary assessment of general population exposure to perfluoroalkyl substances through diet in Greece

Food and drinking water intake are the major routes of exposure to perfluoroalkyl substances (PFASs) for humans. In this study an initial oral exposure assessment of the non-occupationally exposed general Greek population to PFASs is presented. Levels of PFOA and PFOS determined in the present study in 128 food items from the Greek market and previously published analytical results of 43 water samples and 76 egg samples from Greece were combined with food availability data of the DAFNE-ANEMOS database for the calculation of oral intake of PFASs. Fish form the food group with the highest concentration in both PFOA and PFOS. For the general Greek population the estimated average daily intake in PFOA and PFOS when applying the lowerbound mean concentrations in food and drinking water samples is 0.49 and 0.91 ng kg^-1 body weight (b.w.) respectively. The main contributor to oral PFAS intake is fish. A pharmacokinetic model is applied to estimate total intake from blood serum levels reported previously and the predicted values are in agreement with lowerbound estimated values. Weekly intake estimated values are below the tolerable weekly intake recently proposed by EFSA.

Level and determinants of serum perfluoroalkyl acids (PFAAs) in a population in Klang Valley, Malaysia

For decades, perfluoroalkyl acids (PFAAs) have been commonly used for industrial and commercial purposes due to their water- and stain-resistant properties. Persistent pollutants that contain PFAAs have been associated with adverse health effects in humans, and many studies have documented dietary intake, indoor air inhalation, and dermal contact as the potential routes for human exposure to PFAAs. The aim of this study was to assess the level of PFAAs in the serum samples of a general population in a specific region in Malaysia. Using 219 serum samples collected from residents of Klang Valley, Malaysia, the levels of nine PFAAs were analyzed using liquid chromatography-tandem mass spectrometry. In addition, questionnaire surveys on the dietary habits and lifestyles of the subjects were conducted. The results showed that PFAA concentrations of up to 32.57 ng/mL were detected in all serum samples. In 82.6% of the participants, at least seven PFAAs were detected in the serum samples, with perfluorooctanesulfonic acid being the predominant PFAA (median = 8.79 ng/mL). In the adjusted regression model, the concentrations of most PFAAs were higher in men than in women and positively correlated with age, although body mass index and smoking were not significantly associated with the serum PFAA concentrations. Taking into consideration the lifestyle variables, significant associations were found between nonstick cookware and perfluorononanoic acid, between dental floss and cosmetics and perfluorodecanoic acid (PFDA), and between leather sofa and perfluoroundecanoic acid (PFUnDA). Besides, consumption of beef was significantly associated with increased levels of serum PFUnDA, whereas consumption of lamb and chicken eggs was negatively associated with the serum levels of PFUnDA and PFDA, respectively.

Accumulation of perfluoroalkyl substances in lysimeter-grown rice in Japan using tap water and simulated contaminated water

Perfluoroalkyl substances (PFASs) are a group of contaminants of concern in agricultural crops, but little is known of their accumulation or behavior in grains. We grew Japanese rice (Oryza sativa subsp. indica) in lysimeters irrigated with tap water or tap water plus simulated contaminated water for 2 years, then analyzed the roots, straw, unhulled rice, white rice, bran, soil, and water for PFASs residues. Total fluorine was measured by combustion ion chromatography. Estimated per-plant residue levels were 3.0 pg perfluorooctanesulfonic acid (PFOS) (bran: 0.5%, hull: 99.5%), 0.54 pg N-ethylperfluorooctanesulfonamide (N-EtFOSA) (white rice: 67%, hull: 33%), 1.2 pg perfluorobutanoic acid (PFBA) (white rice: 13%, bran: 7%, hull: 79%), 0.68 pg perfluoropentanoic acid (hull: 100%), 0.50 pg perfluorohexanoic acid (PFHxA) (white rice: 65%, bran: 16%, hull: 19%), 0.21 pg perfluoroheptanoic acid (hull: 100%), 0.25 pg perfluorooctanoic acid (PFOA) (hull: 100%), and 0.12 pg perfluorodecanoic acid (PFNA) (white rice: 81%, bran: 19%). Estimated daily PFASs intakes were <1-3 ng perfluorooctanesulfonamide, <1-7 ng N-EtFOSA, 1-2 ng PFBA, <3-4 ng PFHxA, and 1-2 ng PFNA. Estimated PFOS, PFOA, and total PFASs in straw feed were 0.4, 0.1, and 2 kg yr^-1 and 0.7, 0.4, and 8 kg yr^-1 in 2015 and 2016, respectively. Estimated PFOS, PFOA, and total PFASs in straw fertilizer were 4, 1, and 23 kg yr^-1 and 7, 4, and 86 kg yr^-1 in 2015 and 2016, respectively. PFASs accumulation may cause longer residence time in agricultural systems owing to straw being used as animal feed and organic fertilizer.

Field-scale evaluation of the uptake of Perfluoroalkyl substances from soil by rice in paddy fields in South Korea

The concentrations of 17 perfluoroalkyl substances (PFASs) were investigated in paddy soil, void water, and brown rice collected from 30 paddy fields to examine the uptake of PFASs from soil by rice. The total concentrations of PFASs ranged from 7.76 to 3020 ng/L (average = 166 ng/L) in void water, 0.120 to 13.9 ng/g dry-weight (dw) (1.92 ng/g dw) in paddy soils, and from not-detected to 1.85 ng/g (0.403 ng/g) in brown rice samples. The highest PFAS concentrations were observed in brown rice cultivated in a paddy field where high levels of PFASs were observed in void water and paddy soil. Among target PFAS compounds, perfluorocarboxylic acids were dominant and detected in all matrices, and perfluorooctanoic acid (PFOA) was the most predominant compound in brown rice and void water. Significant positive correlations were examined for some detected PFASs between each matrix. PFOA in brown rice was positively correlated with PFOA in void water as well as perfluorodecanoic acid (PFDA) in paddy soil (p < 0.01). PFOA in void water also had correlated with PFDA in paddy soil. However, there was no correlation of other compounds between each matrix, except for correlations of perfluorononanoic acid (PFNA) and PFDA in paddy soil with those in void water, respectively (p < 0.05). Moreover, PFOA concentration in brown rice (0.093 ng/g) was much higher than one in white rice detected with a non-detectable level.

A Review of Perfluoroalkyl Acids (PFAAs) in terms of Sources, Applications, Human Exposure, Dietary Intake, Toxicity, Legal Regulation, and Methods of Determination

Per- and polyfluoroalkyl substances (PFASs) are widely distributed across the world and are expected to be of concern to human health and the environment. The review focuses on perfluoroalkyl acids (PFAAs) and, in particular, on the most frequently discussed perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkane sulfonic acids (PFSAs). In this study, some basic information concerning PFASs is reviewed, focusing mainly on PFAAs (perfluoroalkyl acids). We have made efforts to systemize their division into groups according to chemical structure, describe their basic physicochemical properties, characterize production technologies, and determine potential human exposure routes with particular reference to oral exposure. A variety of possible toxicological effects to human health are also discussed. In response to increasing public concern about the toxicity of PFAAs, an evaluation of dietary intake has been undertaken for two of the most commonly known PFAAs: perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). As summarized in this study, PFAAs levels need further assessment due to the science-based TWI standards laid down by the EFSA’s CONTAM Panel regarding the risk to human health posed by the presence of perfluorooctane sulfonic acid and perfluorooctanoic acid in food (tolerable weekly intakes of PFOA and PFOS set up to 6 ng·kg−1·bw·week−1 and 13 ng·kg−1·bw·week−1, respectively). Current legislation, relevant legislation on PFAAs levels in food, and the most popular methods of analysis in food matrices are described.