Presence and sources of anthropogenic perfluoroalkyl acids in high-consumption tap-water based beverages

Association of diet with per- and polyfluoroalkyl substances in plasma and human milk in the New Hampshire Birth Cohort Study

Per- and polyfluoroalkyl substances (PFAS) are related to various adverse health outcomes, and food is a common source of PFAS exposure. Dietary sources of PFAS have not been adequately explored among U.S. pregnant individuals. We examined associations of dietary factors during pregnancy with PFAS concentrations in maternal plasma and human milk in the New Hampshire Birth Cohort Study. PFAS concentrations, including perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), and perfluorodecanoate (PFDA), were measured in maternal plasma collected at ∼28 gestational weeks and human milk collected at ∼6 postpartum weeks. Sociodemographic, lifestyle and reproductive factors were collected from prenatal questionnaires and diet from food frequency questionnaires at ∼28 gestational weeks. We used adaptive elastic net (AENET) to identify important dietary variables for PFAS concentrations. We used multivariable linear regression to assess associations of dietary variables selected by AENET models with PFAS concentrations. Models were adjusted for sociodemographic, lifestyle, and reproductive factors, as well as gestational week of blood sample collection (plasma PFAS), postpartum week of milk sample collection (milk PFAS), and enrollment year. A higher intake of fish/seafood, eggs, coffee, or white rice during pregnancy was associated with higher plasma or milk PFAS concentrations. For example, every 1 standard deviation (SD) servings/day increase in egg intake during pregnancy was associated with 4.4 % (95 % CI: 0.6, 8.4), 3.3 % (0.1, 6.7), and 10.3 % (5.6, 15.2) higher plasma PFOS, PFOA, and PFDA concentrations respectively. Similarly, every 1 SD servings/day increase in white rice intake during pregnancy was associated with 7.5 % (95 % CI: -0.2, 15.8) and 12.4 % (4.8, 20.5) greater milk PFOS and PFOA concentrations, respectively. Our study suggests that certain dietary factors during pregnancy may contribute to higher PFAS concentrations in maternal plasma and human milk, which could inform interventions to reduce PFAS exposure for both birthing people and offspring.

Profile of per- and polyfluoroalkyl substances, source appointment, and determinants in Argentinean postpartum women

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) are a group of synthetic chemicals with potential adverse health effects. Information concerning PFAS concentrations in relation to pregnancy is scarce in South America and non-existent in Argentina.

AIM

We aimed to investigate an extended maternal PFAS profile herein serum concentrations in a regional and global view, source appointment, and determinants in Argentinean women.

METHODS

A cross-sectional study with a sampling period from 2011 to 2012 included 689 women from Ushuaia and Salta in Argentina. Serum samples collected two days postpartum were analyzed by ultra-high pressure liquid chromatography coupled to electrospray negative ionisation tandem-quadrupole mass-spectrometry. Principal Component Analysis (PCA) following absolute principal component score-multiple linear regression (APCS-MLR) was used for PFAS source appointments. Determinants of PFAS were explored through a MLR approach. A review of previous studies within the same period was conducted to compare with present levels.

RESULTS

Argentinean PFAS concentrations were the lowest worldwide, with PFOS (0.74 ng/mL) and PFOA (0.11 ng/mL) as the dominant substances. Detection frequencies largely aligned with the compared studies, indicating the worldwide PFAS distribution considering the restrictions. The PCA revealed region-specific loading patterns of two component groups of PFAS, a mixture of replaced and legacy substances in Ushuaia and long-chain in Salta. This might relate to a mix of non-diet and diet exposure in Ushuaia and diet in Salta. Region, age, lactation, parity, household members, migration, bottled water, and freshwater fish were among the determinants of various PFAS.

CONCLUSION

This is the first study to monitor human PFAS exposure in Argentina. Maternal PFAS concentrations were the lowest observed worldwide in the same period. Exposure contributions are suggested to be affected by restrictions and substitutions. Given the limited population-based studies and the emergence of PFAS, it is essential to conduct further monitoring of PFAS in Argentina and South America.

The sources and bioaccumulation of per- and polyfluoroalkyl substances in animal-derived foods and the potential risk of dietary intake

Per- and polyfluoroalkyl substances (PFAS) have attracted increasing attention due to their environmental persistence and potential toxicity. Diet is one of the main routes of human exposure to PFAS, particularly through the consumption of animal-derived foods (e.g., aquatic products, livestock and poultry, and products derived from them). This review summarizes the source, bioaccumulation, and distribution of PFAS in animal-derived foods and key influential factors. In most environmental media, perfluorooctanoic acid and perfluorooctane sulfonate are the dominant PFAS, with the levels of short-chain PFAS such as perfluorobutyric acid and perfluorohexane sulfonate surpassing them in some watersheds and coastal areas. The presence of PFAS in environmental media is mainly influenced by suspended particulate matter, microbial communities as well as temporal and spatial factors, such as season and location. Linear PFAS with long carbon chains (C ≥ 7) and sulfonic groups tend to accumulate in organisms and contribute significantly to the contamination of animal-derived foods. Furthermore, PFAS, due to their protein affinity, are prone to accumulate in the blood and protein-rich tissues such as the liver and kidney. Species differences in PFAS bioaccumulation are determined by diet, variances in protein content in the blood and tissues and species-specific activity of transport proteins. Carnivorous fish usually show higher PFAS accumulation than omnivorous fish. Poultry typically metabolize PFAS more rapidly than mammals. PFAS exposures in the processing of animal-derived foods are also attributable to the migration of PFAS from food contact materials, especially those in higher-fat content foods. The human health risk assessment of PFAS exposure from animal-derived foods suggests that frequent consumption of aquatic products potentially engender greater risks to women and minors than to adult males. The information and perspectives from this review would help to further identify the toxicity and migration mechanism of PFAS in animal-derived foods and provide information for food safety management.

(-)-Epigallocatechin-3-Gallate Reduces Perfluorodecanoic Acid-Exacerbated Adiposity and Hepatic Lipid Accumulation in High-Fat Diet-Fed Male C57BL/6J Mice

Perfluorodecanoic acid (PFDA), an enduring and harmful organic pollutant, is widely employed in diverse food-related sectors. Our previous studies have provided evidence that PFDA has the potential to facilitate obesity and hepatic fat accumulation induced by high-fat diet (HFD) intake. Epigallocatechin-3-gallate (EGCG), a polyphenol found in green tea, has been suggested to possess potential preventive effects against metabolic abnormalities and fatty liver. The purpose of this research was to investigate the effects of EGCG on PFDA-exacerbated adiposity and hepatic lipid accumulation in HFD-fed mice. The results showed that EGCG reduced body weight gain; tissue and organ weights; blood glucose, serum insulin, HOMA-IR, leptin, and lipid parameters; serum inflammatory cytokines (IL-1β, IL-18, IL-6, and TNF-α); and hepatic lipid accumulation in PFDA-exposed mice fed an HFD. Further work showed that EGCG improved liver function and glucose homeostasis in mice fed an HFD and co-exposed to PFDA. The elevated hepatic mRNA levels of SREBP-1 and associated lipogenic genes, NLRP3, and caspase-1 in PFDA-exposed mice fed an HFD were significantly decreased by EGCG. Our work provides evidence for the potential anti-obesity effect of EGCG on co-exposure to HFD and PFDA and may call for further research on the bioactivity of EGCG to attenuate the endocrine disruption effects of long-term exposure to pollutants.

The toxicity of perfluorodecanoic acid is mainly manifested as a deflected immune function

BACKGROUND

Perfluorodecanoic acid (PFDA) is a type of perfluoroalkyl acid (PFAA). PFDA has toxicity similar to dioxin; its effect on the body is not through a single target or a single pathway. However, the mechanism at the global level is still unclear.

METHODS AND RESULTS

We treated mice with PFDA and characterized the global changes in gene expression in the liver using microarray analyses. The enriched KEGG pathways and GO analyses revealed that PFDA greatly affected the immune response, which was different from the response of gastric cells previously studied. As a proof of principle, the expressions of IL-1β and IL-18 were both decreased after PFDA treatment, and qRT-PCR and ELISAs verified the reduction of IL-1β and IL-18 in liver tissues. Mechanistic investigations indicated that PFDA inhibited caspase-1 activation, and decreased the mRNA levels of NLRP1, NLRP3, and NLRC4; thus, suggesting that inflammasome assemblies were suppressed. Further microarray data revealed that cIAP2 and its binding proteins, which are critical for regulating inflammasome assembly, were also repressed by PFDA. In addition, flow cytometry results revealed a significant inhibition of Th1 cell differentiation in the livers of PFDA-treated mice.

CONCLUSIONS

The results of this study suggested that one of the main toxic effects of PFDA on livers was the inhibition of immune response.

Independent mode sorption of perfluoroalkyl acids by single and multiple adsorbents

Infinite dilution partition coefficients, K_p,0, of a series of unbranched perfluoralkylacids, PFAAs with 3 to 8 CF₂ units between water and commercially available weak anion exchange (WAX) and strong anion exchange (MAX) polymers, C₁₈-modified silica, hydrophilic-lipophilic balance polymer (HLB), and Al₂O₃ sorbents were determined with self-packed columns using an HPLC-MS/MS setup. The anionic WAX sorbent shows a much higher adsorption affinity (about 450 fold) for PFBA than was observed for the applied hydrophobic sorbent HLB. Since the incremental value for each CF₂ group is smaller when the electrostatic adsorption process is observed, the hydrophobic partition coefficient of HLB supersedes the electrostatic one of WAX at around PFTeDA. Adsorption of PFAAs to Al₂O₃ was weak and did not show a clear chain length dependency. A recently developed independent mode (IM) adsorption model is a more accurate model to combine the electrostatic and hydrophobic interaction terms. This model predicts the correct behaviour of especially short chain PFAAs in soil or sediment sorption experiments. Factors increasing sorption efficiency of well- and ill-defined single and multiple adsorbents towards PFAAs are discussed. The IM model provides a method to optimise sorption remediation strategies of PFAAs in contaminated waters and proposes a two-step strategy, a starting hydrophobic step followed by an electrostatic one to remove more efficiently the short chain PFAAs.

Trends in the Regulation of Per- and Polyfluoroalkyl Substances (PFAS): A Scoping Review

Products containing per- and polyfluoroalkyl substances (PFAS) have been used for decades in industrial and consumer products. These compounds are persistent in the environment, bioaccumulative, and some are toxic to humans and other animals. Since the early 2000s, laws, policies, and regulations have been implemented to reduce the prevalence of PFAS in the environment and exposures to PFAS. We conducted a scoping literature review to identify how PFAS are regulated internationally, at the U.S. national level, and at the U.S. state level, as well as drivers of and challenges to implementing PFAS regulations in the U.S. This review captured peer-reviewed scientific literature (e.g., PubMed), grey literature databases (e.g., SciTech Premium Collection), Google searches, and targeted websites (e.g., state health department websites). We identified 454 relevant documents, of which 61 discussed the non-U.S. PFAS policy, 214 discussed the U.S. national-level PFAS policy, and 181 discussed the U.S. state-level PFAS policy. The drivers of and challenges to PFAS regulation were identified through qualitative analysis. The drivers of PFAS policy identified were political support for regulation, social awareness of PFAS, economic resource availability, and compelling scientific evidence. The challenges to implementing PFAS regulations were political limitations, economic challenges, unclear scientific evidence, and practical challenges. The implications for PFAS policy makers and other stakeholders are discussed.

Dietary patterns and PFAS plasma concentrations in childhood: Project Viva, USA

BACKGROUND

Diet is thought to account for most adult human exposure to per- and polyfluoroalkyl substances (PFAS). Children are particularly vulnerable to adverse health effects of PFAS and may have different eating habits than adults. However, studies of dietary patterns and PFAS in children are limited.

METHODS

We studied 548 Boston-area children with food frequency questionnaire data (89 food items) in early childhood (median age 3.3 years) and plasma concentrations of 6 PFAS quantified in mid-childhood (median age 7.7 years). We used univariate linear regression to examine associations between each food item and PFAS, accounting for multiple comparisons. We next used reduced rank regression (RRR) to estimate overall percent variation in PFAS explained by diet and identify dietary patterns most correlated with PFAS. All models were adjusted for race/ethnicity, maternal education, and household income.

RESULTS

In univariate analyses, 2-(N-methyl-perfluorooctane sulfonamide) acetate (MeFOSAA) plasma concentrations were 17.8% (95% CI: 7.2, 29.5) and 17.0% (95% CI: 6.4, 28.7) higher per SD increment in intake of ice cream and soda, respectively. RRR identified 6 dietary patterns that together explained 18% variation in the plasma concentrations of the 6 PFAS, of which 50% was explained by a dietary pattern consisting of primarily packaged foods (including ice cream and soda) and fish. Children with higher intake of the packaged foods and fish dietary pattern had higher plasma concentrations of all PFAS, particularly MeFOSAA and PFOS.

CONCLUSIONS

Our analysis examined food intake in association with several PFAS in children and identified dietary determinants that may be sources of PFAS exposure or reflect correlated lifestyle or toxicokinetic factors. Further investigation may help inform measures to modify childhood PFAS exposure.

Urine concentrations of perfluoroalkyl acids in children and contributions of dietary factors: a cross-sectional study from Shanghai, China

The production and emission of short-chain perfluoroalkyl acids (PFAAs) has increased over the years to replace long-chain PFAAs, leading to frequent detection in the environment and raising global concerns about the potential impacts on human health. In this study, the specific urine levels of 10 PFAAs were obtained from 189 children (age 8-12 years) from two primary schools located in urban and suburban areas of Shanghai in 2019, and the contributions of dietary factors were investigated. Perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), and perfluorobutane sulfonate (PFBS) were detected in 100%, 99.5%, and 87.3% of the samples, with median concentrations of 20.20 ng/L, 46.50 ng/L, and 20.95 ng/L, respectively. The most abundant PFAA was perfluorooctanoic acid (PFOA), with a median concentration of 78.90 ng/L. The concentration of ∑PFAAs ranged from 61.10 to 4108.93 ng/L, with a median concentration of 253.12 ng/L. Children aged 8-9 years had higher median levels of PFBS, perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS) than children aged 10-12 years. Obese/overweight children had lower levels of PFHpA, PFBS, and PFOS. The intake of red meats, tubers, sugared beverages, fish and seafood, and eggs contributed to higher concentrations of PFAAs, while frequent intake of poultry and soy milk was associated with lower PFAA concentrations.

Environmental contamination and human exposure to PFASs near a fluorochemical production plant: Review of historic and current PFOA and GenX contamination in the Netherlands

Fluorochemical production plants (FPP) are primary emission sources of per- and polyfluoroalkyl substances (PFASs) to the local environment. An FPP located in the Netherlands has historically used perfluorooctanoic acid (PFOA) for fluoropolymer production and is currently using GenX (HFPO-DA; 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)propionic acid) as a replacement. This study reviewed existing data from open access reports and peer reviewed publications on the environmental presence of PFOA and GenX in environmental matrices such as surface water, groundwater, soil and vegetation. Published data on human exposure to PFOA and GenX (i.e. via drinking water and food as well as blood monitoring) were reviewed in order to assess the influence of the FPP on contamination of the local population. Concentrations in environmental and human exposure samples were compared to (inter)national quality standards or risk limits. The data showed higher PFOA and GenX concentrations in surface water, groundwater, soil and vegetation samples taken close to point sources, and the highest observed concentrations exceeded these standards and limits (except for PFOA in soil). Drinking water and food also contained higher PFOA and GenX concentrations in samples taken close to point sources compared to samples further away. Tolerable daily intake (TDIs) for both PFASs were exceeded, however, only in a maximum exposure scenario. Blood monitoring of the local population near the FPP, and FPP workers, confirmed high exposure can occur as blood concentrations of several individuals exceeded the safe level. This paper provides a comprehensive overview on PFOA and GenX contamination close to point sources in the Netherlands.

Dietary characteristics associated with plasma concentrations of per- and polyfluoroalkyl substances among adults with pre-diabetes: Cross-sectional results from the Diabetes Prevention Program Trial

Diet is assumed to be the main source of exposure to per- and polyfluoroalkyl substances (PFAS) in non-occupationally exposed populations, but studies on the diet-PFAS relationship in the United States are scarce. We extracted multiple dietary variables, including daily intakes of food group, diet scores, and dietary patterns, from self-reported dietary data collected at baseline (1996-1999) from adults with pre-diabetes enrolled in the Diabetes Prevention Program, and used linear regression models to evaluate relationships of each dietary variable with plasma concentrations of six PFAS (perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), 2-(N-ethyl-perfluorooctane sulfonamido) acetic acid (EtFOSAA), 2-(N-methyl-perfluorooctane sulfonamido) acetic acid (MeFOSAA), perfluorononanoic acid (PFNA) adjusting for covariates. Participants (N = 941, 65% female, 58% Caucasian, 68% married, 75% with higher education, 95% nonsmoker) had similar PFAS concentrations compared to the general U.S. population during 1999-2000. Using a single food group approach, fried fish, other fish/shellfish, meat and poultry had positive associations with most PFAS plasma concentrations. The strongest effect estimate detected was between fried fish and PFNA [13.6% (95% CI: 7.7, 19.9) increase in median concentration per SD increase]. Low-carbohydrate and high protein diet score had positive association with plasma PFHxS. Some food groups, mostly vegetables and fruits, and the Dietary Approaches to Stop Hypertension diet score had inverse associations with PFOS and MeFOSAA. A vegetable diet pattern was associated with lower plasma concentrations of MeFOSAA, while high-fat meat and low-fiber and high-fat grains diet patterns were associated with higher plasma concentrations of PFOS, PFHxS, MeFOSAA and PFNA. We summarized four major dietary characteristics associated with variations in PFAS plasma concentrations in this population. Specifically, consuming more meat/fish/shellfish (especially fried fish, and excluding Omega3-rich fish), low-fiber and high-fat bread/cereal/rice/pasta, and coffee/tea was associated with higher plasma concentrations while dietary patterns of vegetables, fruits and Omega-3 rich fish were associated with lower plasma concentrations of some PFAS.

Anthropogenic gadolinium in tap water and in tap water-based beverages from fast-food franchises in six major cities in Germany

Gadolinium-based contrast agents used in magnetic resonance imaging are difficult to impossible to remove in wastewater treatment plants, and may enter groundwater production wells and hence municipal tap water via bank filtration. As anthropogenic gadolinium (Gd) may be accompanied by other, more harmful waste water-derived (micro)pollutants such as endocrine disruptors, we investigated the potential pathway of anthropogenic Gd into popular tap water-based beverages sold in highly frequented fast food restaurants. We, therefore, determined the concentration and distribution of geogenic and anthropogenic rare earth elements (REE) in tap water and in a related tap water-based popular soft drink (Coca Cola) from two fast food franchises (McDonalds and Burger King) in six major German cities. We observed anthropogenic Gd in both tap water and corresponding soft drinks in all investigated cities, extending the database for anthropogenic Gd in tap waters and highlighting its widespread distribution. In Berlin and Düsseldorf, where tap water is (mainly) produced by river bank filtration, 85 to 99% of the total Gd is of anthropogenic origin. The surprisingly high anthropogenic fraction (91%) in tap water from Munich reveals that even the shallow groundwater tapped in two Alpine valleys is eventually exposed to anthropogenic pollution. The REE distribution in post-mix soft drinks generally follows that of the corresponding tap water, except for enrichments of ytterbium (Yb), lutetium (Lu) and cerium (Ce), which are derived from the syrup. The concentration of anthropogenic Gd is similar in the soft drinks and in the corresponding tap water, demonstrating that the highly stable Gd-based contrast agents are not removed in soda fountains but are directly transferred to the beverages. This study highlights a pathway for anthropogenic waste water-derived xenobiotics such as pharmaceuticals and endocrine disruptors into the food chain, and hence, reveals the potential for human exposure to potentially harmful anthropogenic compounds.

Cola Beverages: Clinical Uses versus Adverse Effects

Methods:

In this systematic review we tried to explore these new uses for practitioners and also reemphasize on the most evidence-based complications of cola consumption like bone loss and metabolic and cardiovascular adverse effects in cases of misuse and overuse from both clinical and nutritional points of view via searching the PubMed database.

Results:

We chose 145 journal articles from the most relevant ones plus 30 extra references and categorized their topics in two classes of medical uses and adverse effects.

Conclusion:

It could be stated that cola beverages have demonstrated interesting uses and benefits in medicine but their use should be regulated as strict as possible.

Perfluoroalkyl substances in adolescents in northern Norway: Lifestyle and dietary predictors. The Tromsø study, Fit Futures 1

Perfluoroalkyl substances (PFASs) are environmentally persistent chemicals widely used in many consumer products due to water and oil proofing and fire-resistant properties. Several PFASs are recognized as environmental pollutants. This study investigated serum concentrations of 18 different PFASs and their associations with diet and lifestyle variables in 940 adolescents (age 15-19 years) who participated in the Fit Futures 1 study in the Troms arctic district of Norway. Serum concentrations of PFASs were analyzed by ultrahigh pressure liquid chromatography coupled to a triple quadrupole mass spectrometer (UHPLC-MS/MS). The most abundant PFASs in this population were perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorohexane sulfonate (PFHxS), perfluorononanoate (PFNA) and perfluorodecanoate (PFDA) that were found in 99% of the participants. Perfluoroheptane sulfonate (PFHpS) was found in 98% of the participants. Median concentrations were: PFOS 6.20 ng/mL, PFOA 1.92 ng/mL, PFHxS 0.71 ng/mL, PFNA 0.50 ng/mL, PFDA 0.21 ng/mL and PFHpS 0.15 ng/mL. Median of PFASs sum concentration (∑PFAS) was 10.7 ng/mL, the concentration range was 2.6-200.8 ng/mL. Intake of fat fish, fish liver, seagull eggs, reindeer meat and drinks with sugar were the main dietary predictors of several PFASs. Intake of junk food (pizza, hamburger, sausages) was positively associated with PFNA, intake of canned food was positively associated with PFHxS. Intake of fruits and vegetables, milk products, snacks and candy was not associated with PFASs concentrations. Lean fish intake was positively associated with PFUnDA, but not with other PFASs. There was a positive association of ∑PFAS, PFHxS, PFOA, PFNA and PFDA with chewed tobacco use.

Estimating human exposure to perfluoroalkyl acids via solid food and drinks: Implementation and comparison of different dietary assessment methods

BACKGROUND

Diet is a major source of human exposure to hazardous environmental chemicals, including many perfluoroalkyl acids (PFAAs). Several assessment methods of dietary exposure to PFAAs have been used previously, but there is a lack of comparisons between methods.

AIM

To assess human exposure to PFAAs through diet by different methods and compare the results.

METHODS

We studied the dietary exposure to PFAAs in 61 Norwegian adults (74% women, average age: 42 years) using three methods: i) by measuring daily PFAA intakes through a 1-day duplicate diet study (separately in solid and liquid foods), ii) by estimating intake after combining food contamination with food consumption data, as assessed by 2-day weighted food diaries and iii) by a Food Frequency Questionnaire (FFQ). We used existing food contamination data mainly from samples purchased in Norway and if not available, data from food purchased in other European countries were used. Duplicate diet samples (n=122) were analysed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) to quantify 15 PFAAs (11 perfluoroalkyl carboxylates and 4 perfluoroalkyl sulfonates). Differences and correlations between measured and estimated intakes were assessed.

RESULTS

The most abundant PFAAs in the duplicate diet samples were PFOA, PFOS and PFHxS and the median total intakes were 5.6ng/day, 11ng/day and 0.78ng/day, respectively. PFOS and PFOA concentrations were higher in solid than liquid samples. PFOS was the main contributor to the contamination in the solid samples (median concentration 14pg/g food), while it was PFOA in the liquid samples (median concentrations: 0.72pg/g food). High intakes of fats, oils, and eggs were statistically significantly related to high intakes of PFOS and PFOA from solid foods. High intake of milk and consumption of alcoholic beverages, as well as food in paper container were related to high PFOA intakes from liquid foods. PFOA intakes derived from food diary and FFQ were significantly higher than those derived from duplicate diet, but intakes of PFOS derived from food diary and FFQ were significantly lower than those derived from duplicate diet. We found a positive and statistically significant correlation between the PFOS intakes derived from duplicate diet with those using the food diary (rho=0.26, p-value=0.041), but not with the FFQ. Additionally, PFOA intakes derived by duplicate diet were significantly correlated with estimated intakes from liquid food derived from the food diary (rho=0.34, p=0.008) and estimated intakes from the FFQ (rho=0.25, p-value=0.055).

CONCLUSIONS

We provide evidence that a food diary or a FFQ-based method can provide comparable intake estimates to PFOS and PFOA intakes derived from a duplicate diet study. These less burdensome methods are valuable and reliable tools to assess dietary exposure to PFASs in human studies.

Perfluoroalkyl substances in the Maltese environment - (I) surface water and rain water

The presence of perfluoroalkyl substances (PFASs) in rain water on the Maltese Islands is reported here for the first time and an extensive survey of these substances in surface water also reported. The Maltese archipelago lies at the centre of the Mediterranean Sea and consists of three main inhabited islands: Malta, Gozo and Comino. Surface water was collected from 41 valleys during the months of February and March 2015 at the peak of the wet season. Rain water was collected during the months of December 2014, February, August, September and October 2015. PFASs were extracted from the water samples using solid phase extraction and the extracts were then analysed using ultra performance liquid chromatography coupled to mass spectrometry in tandem (UPLC-MS/MS). All surface and rain water samples were contaminated with at least one PFAS. PFOS (<LOD - 8.6ng/L) and PFOA (ND - 16ng/L) were the two major PFASs being detected in 100% and 95% of the surface waters respectively. The ΣPFAS concentrations in rain water ranged between 0.38ng/L (1st October 2015) and 6ng/L (21st February 2015). The Maltese archipelago is surrounded by sea and disconnected from any other mainland; therefore the results confirm that remote environments can become contaminated by PFASs from rain events depending on wind prevailing trajectories.

Persistent Organic Pollutants and the Association with Maternal and Infant Thyroid Homeostasis: A Multipollutant Assessment

BACKGROUND

Disruption of thyroid homeostasis has been indicated in human studies targeting effects of persistent organic pollutants (POPs). Influence on the maternal thyroid system by POPs is of special interest during pregnancy because such effects could impair infant thyroid homeostasis.

OBJECTIVES

We investigated the association between POPs and thyroid-stimulating hormone (TSH) and thyroid hormones (THs) in mother and child pairs from the Northern Norway Mother-and-Child Contaminant Cohort Study (MISA).

METHODS

Nineteen POPs and 10 thyroid parameters were analyzed in serum from 391 pregnant women in their second trimester. In addition, TSH concentrations in heel-prick samples from the infants were analyzed by the Norwegian Newborn Screening program. Association studies with a multipollutant approach were performed using multivariate analyses; partial least squares (PLS) regression, hierarchical clustering, and principal component analysis (PCA).

RESULTS

Several POPs were significantly associated with TSH and THs: a) PFOS was positively associated with TSH; b) PCBs, HCB, and nonachlors were inversely associated with T3, T4, and FT4; and, c) PFDA and PFUnDA were inversely associated with T3 and FT3. After mutual adjustments for the other contaminants, only PFDA and PFUnDA remained significantly associated with T3 and FT3, respectively. Infants born to mothers within the highest TSH quartile had 10% higher mean concentrations of TSH compared with children born to mothers in the lowest TSH quartile.

CONCLUSION

The present results suggest that background exposures to POPs can alter maternal thyroid homeostasis. This research contributes to the understanding of multipollutant exposures using multivariate statistical approaches and highlights the complexity of investigating environmental concentrations and mixtures in regard to maternal and infant thyroid function. Citation: Berg V, Nøst TH, Pettersen RD, Hansen S, Veyhe AS, Jorde R, Odland JØ, Sandanger TM. 2017. Persistent organic pollutants and the association with maternal and infant thyroid homeostasis: a multipollutant assessment. Environ Health Perspect 125:127-133; http://dx.doi.org/10.1289/EHP152.

Perfluoroalkyl acids-induced liver steatosis: Effects on genes controlling lipid homeostasis

Persistent presence of perfluoroalkyl acids (PFAAs) in the environment is due to their extensive use in industrial and consumer products, and their slow decay. Biochemical tests in rodent demonstrated that these chemicals are potent modifiers of lipid metabolism and cause hepatocellular steatosis. However, the molecular mechanism of PFAAs interference with lipid metabolism remains to be elucidated. Currently, two major hypotheses are that PFAAs interfere with mitochondrial beta-oxidation of fatty acids and/or they affect the transcriptional activity of peroxisome proliferator-activated receptor α (PPARα) in liver. To determine the ability of structurally-diverse PFAAs to cause steatosis, as well as to understand the underlying molecular mechanisms, wild-type (WT) and PPARα-null mice were treated with perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), or perfluorohexane sulfonate (PFHxS), by oral gavage for 7days, and their effects were compared to that of PPARα agonist WY-14643 (WY), which does not cause steatosis. Increases in liver weight and cell size, and decreases in DNA content per mg of liver, were observed for all compounds in WT mice, and were also seen in PPARα-null mice for PFOA, PFNA, and PFHxS, but not for WY. In Oil Red O stained sections, WT liver showed increased lipid accumulation in all treatment groups, whereas in PPARα-null livers, accumulation was observed after PFNA and PFHxS treatment, adding to the burden of steatosis observed in control (untreated) PPARα-null mice. Liver triglyceride (TG) levels were elevated in WT mice by all PFAAs and in PPARα-null mice only by PFNA. In vitro β-oxidation of palmitoyl carnitine by isolated rat liver mitochondria was not inhibited by any of the 7 PFAAs tested. Likewise, neither PFOA nor PFOS inhibited palmitate oxidation by HepG2/C3A human liver cell cultures. Microarray analysis of livers from PFAAs-treated mice indicated that the PFAAs induce the expression of the lipid catabolism genes, as well as those involved in fatty acid and triglyceride synthesis, in WT mice and, to a lesser extent, in PPARα-null mice. These results indicate that most of the PFAAs increase liver TG load and promote steatosis in mice We hypothesize that PFAAs increase steatosis because the balance of fatty acid accumulation/synthesis and oxidation is disrupted to favor accumulation.

Perfluoroalkyl substances assessment in drinking waters from Brazil, France and Spain

Human exposure to perfluoroalkyl substances (PFASs) occurs primarily via dietary intake and drinking water. In this study, 16 PFASs have been assessed in 96 drinking waters (38 bottled waters and 58 samples of tap water) from Brazil, France and Spain. The total daily intake and the risk index (RI) of 16 PFASs through drinking water in Brazil, France and Spain have been estimated. This study was carried out using an analytical method based on an online sample enrichment followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The quality parameters of the analytical method were satisfactory for the analysis of the 16 selected compounds in drinking waters. Notably, the method limits of detection (MLOD) and method limits of quantification (MLOQ) were in the range of 0.15 to 8.76ng/l and 0.47 to 26.54ng/l, respectively. The results showed that the highest PFASs concentrations were found in tap water samples and the more frequently found compound was perfluorooctanesulfonic acid (PFOS), with mean concentrations of 7.73, 15.33 and 15.83ng/l in French, Spanish and Brazilian samples, respectively. In addition, PFOS was detected in all tap water samples from Brazil. The highest level of PFASs contamination in a single sample was 140.48ng/l in a sample of Spanish tap water. In turn, in bottled waters the highest levels were detected in a French sample with 116ng/l as the sum of PFASs. Furthermore, the most frequent compounds and those at higher concentrations were perfluoroheptanoic acid (PFHpA) with a mean of frequencies in the three countries of 51.3%, followed by perfluorobutanesulfonic acid (PFBS) (27.2%) and perfluorooctanoic acid (PFOA) (23.0%). Considering that bottled water is approximately 38% of the total intake, the total PFASs exposure through drinking water intake for an adult man was estimated to be 54.8, 58.0 and 75.6ng/person per day in Spain, France and Brazil, respectively. However, assuming that the water content in other beverages has at least the same levels of contamination as in bottled drinking water, these amounts were increased to 72.2, 91.4 and 121.0ng/person per day for an adult man in Spain, France and Brazil, respectively. The results of total daily intake in different gender/age groups showed that children are the most exposed population group through hydration with maximum values in Brazil of 2.35 and 2.01ng/kg body weight (BW)/day for male and female, respectively. Finally, the RI was calculated. In spite of the highest values being found in Brazil, it was demonstrated that, in none of the investigated countries, drinking water pose imminent risk associated with PFASs contamination.

Assessing the relationship between perfluoroalkyl substances, thyroid hormones and binding proteins in pregnant women; a longitudinal mixed effects approach

The mechanisms involved in thyroid homeostasis are complex, and perfluoroalkyl substances (PFASs) have been indicated to interfere at several levels in this endocrine system. Disruption of the maternal thyroid homeostasis during early pregnancy is of particular concern, where subclinical changes in maternal thyroid hormones (THs) may affect embryonic and foetal development. The present study investigated associations between THs, thyroid binding proteins (TH-BPs) and PFAS concentrations in pregnant women from Northern Norway. Women participating in The Northern Norway Mother-and-Child contaminant Cohort Study (MISA) donated a blood sample at three visits related to their pregnancy and postpartum period (during the second trimester, 3 days and 6 weeks after delivery) in the period 2007-2009. Participants were assigned to quartiles according to PFAS concentrations during the second trimester and mixed effects linear models were used to investigate potential associations between PFASs and repeated measurements of THs, TH-BPs, thyroxin binding capacity and thyroid peroxidase antibodies (anti-TPOs). Women within the highest perfluorooctane sulfonate (PFOS) quartile had 24% higher mean concentrations of thyroid stimulating hormone (TSH) compared to the first quartile at all sampling points. Women within the highest quartiles of perfluorodecanoate (PFDA) had 4% lower mean concentrations of triiodothyronine (T3) and women within the highest quartile of perfluoroundecanoate (PFUnDA) had 3% lower mean concentrations of free triiodothyronine (FT3). Further, the difference in concentrations and the changes between three time points were the same for the PFAS quartiles. Thyroxin binding capacity was associated with all the THs and TH-BPs, and was selected as a holistic adjustment for individual changes in TH homeostasis during pregnancy. Finally, adjusting for maternal iodine status did not influence the model predictions. Findings in the present study suggest modifications of TH homeostasis by PFASs in a background exposed maternal population. The variation in levels of THs between PFAS quartiles was within normal reference ranges and may not be of clinical significance in the pregnant woman. However, subtle individual changes in maternal THs may have significant consequences for foetal health.

Acute and chronic toxicity of short chained perfluoroalkyl substances to Daphnia magna

The aim of this study was to evaluate the aquatic toxicity of a C4-C6 chemistry based fluoroalkylated polymer and the perfluoroalkyl carboxylic acids, PFBA, PFHxA and PFOA to Daphnia magna. The acute toxicity decreased with decreasing carbon chain length, but the polymer did not show a dose related effect. In a chronic toxicity test performed with PFHxA, mortality was observed at similar concentrations as in the acute toxicity test, indicating that toxicity did not increase with increasing exposure time. Effects on mortality, reproduction and population growth rate occurred at similar concentrations, indicating no specific effect of PFHxA on sublethal endpoints. C4-C6 chemistry is thus less hazardous to daphnids than C7-C8 chemistry. Yet, these compounds are persistent, hard to remove from the environment and production volumes are increasing.

Elucidating the molecular basis of adverse health effects from exposure to anthropogenic polyfluorinated compounds using toxicoproteomic approaches

Linear, short-chain polyfluorinated and perfluorinated alkyl compounds, often referred to as PFCs, have been in worldwide use as surfactants and polymer precursors for decades, and environmental dispersal of these highly persistent compounds represents a public health threat. Whereas ubiquitous low-level exposure to these compounds has been demonstrated in human populations from around the world, the exact mechanisms of toxicity and their toxic potency remain subject to investigation and scientific dispute. As with other environmental exposures, a major hurdle for gaining a better understanding of their human health impacts is the limited utility of cell culture and animal models serving as convenient, yet imperfect proxies to human physiology and disease. The present communication provides a brief overview of the current understanding of potential health effects of PFC exposure and examines how new toxicoproteomic methodologies can provide insight into the molecular mechanism of PFC exposure. Furthermore, we showcase an exemplary data set to illustrate how toxicoproteomic, population-wide studies might overcome limitations of animal models to more fully understand the metabolism and effects of PFCs and other environmental stressors where it matters most, in human populations experiencing real-world, chronic, low-level exposures.

Maternal serum concentrations of per- and polyfluoroalkyl substances and their predictors in years with reduced production and use

Determining maternal concentrations of per- and polyfluoroalkyl substances (PFASs) and the relative impact of various demographic and dietary predictors is important for assessing fetal exposure and for developing proper lifestyle advisories for pregnant women. This study was conducted to investigate maternal PFAS concentrations and their predictors in years when the production and use of several PFASs declined, and to assess the relative importance of significant predictors. Blood from 391 pregnant women participating in The Northern Norway Mother-and-Child Contaminant Cohort Study (MISA) was collected in the period 2007-2009 and serum analyses of 26 PFASs were conducted. Associations between PFAS concentrations, sampling date, and demographic and dietary variables were evaluated by multivariate analyses and linear models including relevant covariates. Parity was the strongest significant predictor for all the investigated PFASs, and nulliparous women had higher concentrations compared to multiparous women (10 ng/mL versus 4.5 ng/mL in median PFOS, respectively). Serum concentrations of PFOS and PFOA of women recruited day 1-100 were 25% and 26% higher, respectively, compared to those women recruited in the last 167 days of the study (day 601-867), and the concentrations of PFNA, PFDA and PFUnDA increased with age. Dietary predictors explained 0-17% of the variation in concentrations for the different PFASs. Significantly elevated concentrations of PFOS, PFNA, PFDA and PFUnDA were found among high consumers of marine food. The concentrations of PFHxS, PFHpS and PFNA were also increased in high consumers of game and elevated concentrations of PFHpS and PFOS were detected in high consumers of white meat. Study subjects with a high intake of salty snacks and beef had significantly higher concentrations of PFOA. The present study demonstrates that parity, sampling date and birth year are the most important predictors for maternal PFAS concentrations in years following a decrease in production and use of several PFASs. Further, dietary predictors of PFAS concentrations were identified and varied in importance according to compound.

Behaviour and fate of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in drinking water treatment: a review

This article reviews perfluoroalkyl and polyfluoroalkyl substance (PFAS) characteristics, their occurrence in surface water, and their fate in drinking water treatment processes. PFASs have been detected globally in the aquatic environment including drinking water at trace concentrations and due, in part, to their persistence in human tissue some are being investigated for regulation. They are aliphatic compounds containing saturated carbon-fluorine bonds and are resistant to chemical, physical, and biological degradation. Functional groups, carbon chain length, and hydrophilicity/hydrophobicity are some of the important structural properties of PFASs that affect their fate during drinking water treatment. Full-scale drinking water treatment plant occurrence data indicate that PFASs, if present in raw water, are not substantially removed by most drinking water treatment processes including coagulation, flocculation, sedimentation, filtration, biofiltration, oxidation (chlorination, ozonation, AOPs), UV irradiation, and low pressure membranes. Early observations suggest that activated carbon adsorption, ion exchange, and high pressure membrane filtration may be effective in controlling these contaminants. However, branched isomers and the increasingly used shorter chain PFAS replacement products may be problematic as it pertains to the accurate assessment of PFAS behaviour through drinking water treatment processes since only limited information is available for these PFASs.

Perfluorooctane sulfonate (PFOS) contamination of fish in urban lakes: a prioritization methodology for lake management

The contamination of urban lakes by anthropogenic pollutants such as perfluorooctane sulfonate (PFOS) is a worldwide environmental problem. Large-scale, long-term monitoring of urban lakes requires careful prioritization of available resources, focusing efforts on potentially impaired lakes. Herein, a database of PFOS concentrations in 304 fish caught from 28 urban lakes was used for development of an urban-lake prioritization framework by means of exploratory data analysis (EDA) with the aid of a geographical information system. The prioritization scheme consists of three main tiers: preliminary classification, carried out by hierarchical cluster analysis; predictor screening, fulfilled by a regression tree method; and model development by means of a neural network. The predictive performance of the newly developed model was assessed using a training/validation splitting method and determined by an external validation set. The application of the model in the U.S. state of Minnesota identified 40 urban lakes that may contain elevated levels of PFOS; these lakes were not previously considered in PFOS monitoring programs. The model results also highlight ongoing industrial/commercial activities as a principal determinant of PFOS pollution in urban lakes, and suggest vehicular traffic as an important source and surface runoff as a primary pollution carrier. In addition, the EDA approach was further compared to a spatial interpolation method (kriging), and their advantages and disadvantages were discussed.

Perfluorinated alkylated substances in vegetables collected in four European countries; occurrence and human exposure estimations

The human diet is recognised as one possible major exposure route to the overall perfluorinated alkylated substances (PFAS) burden of the human population, resulting directly from contamination of dietary food items, as well as migration of PFAS from food packaging or cookware. Most European countries carry out national monitoring programs (food basket studies) to monitor contamination with pollutants. Usually, for PFASs, non-coordinated approaches are used in Europe, since food basket studies are mainly carried out by national authorities following national requirements and questions, making comparisons between different countries difficult. A harmonised sampling campaign collecting similar food items in a uniform procedure enabling direct comparison between different regions in Europe was designed. We selected four countries (Belgium, Czech Republic, Italy and Norway), representing the four regions of Europe: West, East, South and North. In spring 2010 and 2011, 20 different types of vegetables were sampled in Belgium, Czech Republic, Italy and Norway. Perfluorinated carboxylic acids (PFCAs) were the main group of detected PFASs, with perfluorinated octanoic acid (PFOA) as the most abundant PFCA (with exception of samples from Czech Republic), followed by perfluorinated hexanoic acid and perfluorinated nonanoic acid. Dietary intake estimates for PFOA show only low human exposure due to vegetable consumption for adults and children, mostly governed by high intake of potatoes.

Perfluorinated alkylated acids in groundwater and drinking water: identification, origin and mobility

Human exposure to perfluorinated alkylated acids (PFAA) occurs primarily via the dietary intake and drinking water can contribute significantly to the overall PFAA intake. Drinking water is produced from surface water and groundwater. Waste water treatment plants have been identified as the main source for PFAA in surface waters and corresponding drinking water. However, even though groundwater is an important source for drinking water production, PFAA sources remain largely uncertain. In this paper, we identified different direct and indirect sources of PFAA to groundwater within the catchment area of a public supply well field (PSWF) in The Netherlands. Direct sources were landfill leachate and water draining from a nearby military base/urban area. Indirect sources were infiltrated rainwater. Maximum concentrations encountered in groundwater within the landfill leachate plume were 1.8 μg/L of non branched perfluorooctanoic acid (L-PFOA) and 1.2 μg/L of perfluorobutanoic acid (PFBA). Sum concentrations amounted to 4.4 μg/L total PFAA. The maximum concentration of ΣPFAA in the groundwater originating from the military camp was around 17 ng/L. Maximum concentrations measured in the groundwater halfway the landfill and the PWSF (15 years travel distance) were 29 and 160 ng/L for L-PFOA and PFBA, respectively. Concentrations in the groundwater pumping wells (travel distance >25 years) were much lower: 0.96 and 3.5 ng/L for L-PFOA and PFBA, respectively. The chemical signature of these pumping wells corresponded to the signature encountered in other wells sampled which were fed by water that had not been in contact with potential contaminant sources, suggesting a widespread diffuse contamination from atmospheric deposition.