Depuration kinetics and tissue disposition of PFOA and PFOS in white leghorn chickens (Gallus gallus) administered by subcutaneous implantation

Elimination kinetics and tissue disposition of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in male chickens (Gallus gallus) was determined following exposure by subcutaneous implantation. Chickens were exposed to two levels of PFOA or PFOS for 4wk and then allowed to depurate for an additional 4wk. These exposures did not cause any statistically significant changes in body index, clinical biochemistry or histology among treatments relative to the controls (p>0.05), except that concentrations of total cholesterol and phospholipids were less in chickens exposed to PFOS. The elimination rate constant for PFOA (0.150+/-0.010d(-1)) was approximately six-fold greater than that of PFOS (0.023+/-0.004d(-1)). The greatest concentrations of PFOA and PFOS were found in kidney and liver, respectively. The organ to blood ratio of PFOS concentration was increased after the whole experiment, indicating the importance of organ partitioning of PFOS in elimination kinetics. The depuration half-life of PFOA (t(1/2)=4.6d) and PFOS (t(1/2)=125d) in chickens was calculated.     

Levels of Perfluorinated Chemicals in Municipal Drinking Water from Catalonia,Spain: Public Health Implications

In this study, the concentrations of 13 perfluorinated compounds (PFCs) (PFBuS, PFHxS, PFOS, THPFOS, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnDA, PFDoDA, PFTDA, and PFOSA) were analyzed in municipal drinking water samples collected at 40 different locations from 5 different zones of Catalonia, Spain. Detection limits ranged between 0.02 (PFHxS) and 0.85 ng/L (PFOA). The most frequent compounds were PFOS and PFHxS, which were detected in 35 and 31 samples, with maximum concentrations of 58.1 and 5.30 ng/L, respectively. PFBuS, PFHxA, and PFOA were also frequently detected (29, 27, and 26 samples, respectively), with maximum levels of 69.4, 8.55, and 57.4 ng/L. In contrast, PFDoDA and PFTDA could not be detected in any sample. The most contaminated water samples were found in the Barcelona Province, whereas none of the analyzed PFCs could be detected in two samples (Banyoles and Lleida), and only one PFC could be detected in four of the samples. Assuming a human water consumption of 2 L/day, the maximum daily intake of PFOS and PFOA from municipal drinking water would be, for a subject of 70 kg of body weight, 1.7 and 1.6 ng/kg/day. This is clearly lower than the respective Tolerable Daily Intake set by the European Food Safety Authority. In all samples, PFOS and PFOA also showed lower levels than the short-term provisional health advisory limit for drinking water (200 ng PFOS/L and 400 ng PFOA/L) set by the US Environmental Protection Agency. Although PFOS and PFOA concentrations found in drinking water in Catalonia are not expected to pose human health risks, safety limits for exposure to the remaining PFCs are clearly necessary, as health-based drinking water concentration protective for lifetime exposure is set to 40 ng/L for PFOA.     

Excretion of PFOA and PFOS in Male Rats During a Subchronic Exposure

Perfluorinated compounds (PFCs), a class of synthetic surfactants that are widely used, have become global environmental contaminants because of their high persistence and bioaccumulation. An increasing number of studies have described the pharmacokinetics of PFCs following in vivo exposure, however, few papers have focused on the excretion of these compounds during a period of consecutive exposure. In this study, the excretions of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in male Sprague–Dawley rats gavaged consecutively for 28 days were investigated and compared. The faster elimination rate in urine compared to feces indicated that urinary excretion is the primary clearance route in rats for either PFOA or PFOS. During the first 24 h after administration of PFOA (5 and 20 mg/kg body weight/day), about 24.7–29.6% of the oral dose was excreted through urine and feces, while for PFOS, the excretion amounts were only 2.6–2.8% of the total gavaged doses (5 and 20 mg/kg body weight/day). The excretion rates of both PFCs increased with increasing exposure doses. The higher elimination rate of PFOA through excretion indicated its lower accumulation in rats, thus inducing possible lower toxicities compared to PFOS.     

Transfer of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) From Contaminated Feed Into Milk and Meat of Sheep: Pilot Study

A pilot study was performed with dairy sheep to generate the first data on the transfer of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) from feed into food of animal origin. Corn silage was cultivated on cropland in Lower Saxony in Germany where, as a result of illegal waste disposal in 2006, farmland was contaminated with perfluorinated alkylacids (PFAAs). Two sheep were exposed by way of PFAA-contaminated corn silage to PFOS (1.16 and 1.45 μg/kg body weight [bw]/d, respectively) and PFOA (0.43 and 0.53 μg/kg bw/d) during a period of 21 days. During the PFAA-feeding period, PFOS levels in plasma increased continuously to maximum concentration of 103 and 240 μg/L for sheep 1 and sheep 2, respectively. The PFOA plasma concentration remained low (sheep 1 = 3.3 ± 2.2 μg/L; sheep 2 = 15.6 ± 8.3 μg/L). Data indicate that urinary excretion is the primary clearance route for PFOA (sheep 1 = 51 %; sheep 2 = 55 %), whereas PFOS excretion by way of urine could not be quantified. The highest PFOS excretion (4 to 5 %) was detected in faeces. PFOS was also excreted at higher levels than PFOA by way of milk. During a period of 21 days, a total PFOS transfer into milk ≤ 2 % was calculated. Overall, total excretion of PFOS was significantly lower compared with that of PFOA (PFOS 6 %; PFOA 53 to 56 %). PFOS levels in sheep 1 and sheep 2 were highest in liver (885 and 1,172 μg/kg weight wet [ww], respectively) and lowest in muscle tissue (24.4 and 35.1 μg/kg ww, respectively). PFOA levels in muscle tissue were low for sheep 2 (0.23 μg/kg ww) and not detectable after the PFAA-free feeding period in sheep 1. A slight background load of PFOS in liver (1.5 μg/kg ww) and kidney (0.3 μg/kg ww) was detected in sheep 3 (control).     

Nonlinear associations between dietary exposures to perfluorooctanoic acid (PFOA) or perfluorooctane sulfonate (PFOS) and type 2 diabetes risk in women: Findings from the E3N cohort study

The incidence of type 2 diabetes (T2D) is steadily rising worldwide since the past 30 years. There is increasing interest in understanding the contribution of exposure to endocrine disrupting chemicals (EDCs) to T2D trend. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are stable, persistent, and bioaccumulative synthetic compounds, suspected to act as EDCs and for which the diet is the main route of exposure. We investigated associations between estimated dietary exposure to PFOS and PFOA and the risk of T2D in the large E3N prospective cohort study.Among 71 270 women included in this study, 2680 cases of incident type 2 diabetes were validated during follow-up (1993–2012). Dietary exposure was estimated combining dietary consumption data collected in E3N and food contamination data provided by ANSES in the 2nd French Total Diet Study. The estimated mean dietary exposure to PFOS and PFOA was 0.50?ng/kg _{body weight}/day and 0.86?ng/kg _{body weight}/day respectively. An inverse U-shape association was found when considering PFOA and T2D: women in the 4th, 5th, and 6th decile groups had a HR [95%CI] of 1.21 [1.06–1.46], 1.35 [1.15–1.59], and 1.33 [1.05–1.41], respectively, when compared to women of the 1st decile group, while the other decile groups were not associated to the risk of T2D. The positive association had the strongest effect size for non-obese women (body mass index (BMI) ≤25?kg/m²). No association was found between dietary exposure to PFOS and T2D, except when considering only women with BMI≤25?kg/m2, in which a positive nonlinear association was observed (HR [95%CI]?=?1.46 [1.09–1.96], 1.52 [1.09–2.11], and 1.44 [1.01–2.06] for the 6th, 8th, and 9th decile groups respectively).This is the first study to evaluate the association between dietary exposure to PFOA and PFOS and the risk of developing T2D in a large observational study with over 15 years of follow-up. The present study highlights the importance of studying the effects of EDCs in large epidemiological studies including not occupationally exposed populations, as well as the importance of considering exposure to PFOS and PFOA as a relevant risk factor for T2D.     

Perfluoroalkyl acids in children and their mothers: Association with drinking water and time trends of inner exposures—Results of the Duisburg birth cohort and Bochum cohort studies

BackgroundPerfluoroalkyl acids (PFAAs) are widely distributed in the environment and humans are globally exposed with them. Contaminated drinking water can considerably contribute to the inner exposure levels.ObjectivesWe report the results of a human biomonitoring study with mother–child pairs living in two German cities, one city with PFAA contaminated drinking water in the sub μg/l-range (Bochum) and the other one without contamination (Duisburg). Furthermore, we studied time trends of exposure levels within the Duisburg cohort study.MethodsWe measured seven PFAAs (PFOS, PFOA, PFHxS, PFNA, PFBS, PFDeA, PFDoA) in blood samples by high performance liquid chromatography and tandem mass spectrometry. Samples were taken during pregnancy, from umbilical cord blood (2000–2002), 6–7 years (5th follow-up) and 8–10 years after birth (7th follow-up). The consumption of drinking water was recorded by a standardized questionnaire. Statistical analyses were calculated with multiple linear regression models.ResultsChildren and mothers from Bochum showed higher PFOS and PFOA plasma concentrations than from Duisburg. The median concentrations (μg/l) for children were: PFOS 4.7 vs. 3.3; PFOA 6.0 vs. 3.6 μg/l (p ≤ 0.05). Consumption of >0.7 l (children) and >0.9 l (mothers) drinking water/day was associated with 13–18% higher PFOS, PFOA and PFHxS concentrations in children (p ≤ 0.01), and 22% higher PFOA in mothers (p ≤ 0.05). Within the Duisburg cohort, PFAA levels in children peaked in the 5th follow-up study (medians (μg/l): cord plasma: 2.7 (PFOS); 1.9 (PFOA); 5th follow-up: 3.6 (PFOS); 4.6 (PFOA); 7th follow-up: 3.3 (PFOS); 3.6 (PFOA)). PFOS concentrations in mothers declined from pregnancy to the 5th follow-up (medians: 8.7 vs. 4.0 μg/l).ConclusionResidents exposed to PFOS and PFOA through drinking water showed significantly higher PFOS and PFOA concentrations in blood plasma. Although PFAA concentrations in the children slightly decreased from the 5th to the 7th follow-up, we detected increasing exposure trends with increasing age in the 7th follow-up.     

Perfluorooctanoic Acid and Perfluorooctane Sulfonate in Liver and Muscle Tissue from Wild Boar in Hesse,Germany

Approximately 15,000 tons of wild boar meats (Sus scrofa) are consumed per year in Germany. Boar meat therefore plays a definite role in regard to human diet. Because they are omnivores and because of their high body fat quotient, wild boar may accumulate large concentrations of persistent organic compounds, such as halogenated hydrocarbons, and could thus possibly serve as bioindicators for persistent xenobiotics. In addition, consumption of wild boar meat and liver could lead to increased contaminant levels in humans. Between 2007 and 2009, we tested a total of 529 livers and 506 muscle tissue samples from wild boar for the presence of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). PFOA concentrations ≤45 μg/kg and PFOS concentrations ≤1,780 μg/kg were detected in the liver samples. PFOA concentrations ≤7.4 μg/kg and PFOS concentrations ≤28.6 μg/kg were detected in muscle tissue. Our results show that PFOS may be detected in considerably greater concentrations than PFOA in organs and tissues, which is in agreement with results from other published studies. The comparisons between both organs for the same substance, as well as the comparisons between the substances within an organ, showed clear and statistically significant differences at P < 0.0001. Assuming a tolerable daily intake value of PFOA (1.5 μg/kg bw/d) and PFOS (0.15 μg/kg bw/d) as recommended by the European Food Safety Authority, the results of model calculations based on the maximum concentrations of PFOA and PFOS found in wild boar indicate that there should be no PFC-related health danger resulting from moderate consumption of wild boar meat or liver.     

Concentrations and patterns of perfluoroalkyl acids in Georgia, USA surface waters near and distant to a major use source

Perfluoroalkyl acids (PFAAs) are widespread contaminants emanating from, among other sources, the production/degradation of fluorinated chemicals used in surface repellant applications, such as carpet manufacturing. The goal of the present study was to assess the concentrations of PFAAs, including perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUA), and perfluorooctane sulfonamide (PFOSA), in surface waters both near a wastewater land application system (LAS) in Dalton (GA, USA), home to North America's largest carpet manufacturing site, and distant to this location (Altamaha River, GA, USA) to understand the fate of PFAAs in freshwater. Levels of PFAAs were high in the Conasauga River (GA, USA) downstream of the LAS (PFOA, 253-1,150 ng/L; PFOS, 192-318 ng/L; PFNA, 202-369 ng/L; PFDA, 30.1-113 ng/L; PFUA, 58.0-99.2 ng/L; PFOSA, 162-283 ng/L) and in streams and ponds in Dalton (PFOA, 49.9-299 ng/L; PFOS, 15.8-120 ng/L), and were among the highest measured at a nonspill or direct-release location. Perfluoroalkyl acids in the Altamaha River were much lower (PFOA, 3.0-3.1 ng/L; PFOS, 2.6-2.7 ng/L), but were a source of PFAAs to Georgia's estuaries. A preliminary hazard assessment indicated that concentrations of PFOS at two sites in the Conasauga River exceeded the threshold effect predicted for birds consuming aquatic organisms that are exposed continuously to the PFOS levels at these sites. Assuming that toxicity for all PFAAs quantified is equal to that of PFOS, the sum total PFAAs at two sites within the Conasauga River exceeded PFOS thresholds for aquatic and avian species, warranting additional research.     

Studies on the Toxicological Effects of PFOA and PFOS on Rats Using Histological Observation and Chemical Analysis

As an emerging class of environmentally persistent and bioaccumulative contaminants, perfluorinated compounds (PFCs), especially perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), have been ubiquitously found in the environment. Increasing evidence shows that the accumulated levels of PFCs in animals and the human body might cause potential impairment to their health. In the present study, toxicological effects of PFOA and PFOS on male Sprague–Dawley rats were examined after 28 days of subchronic exposure. Abnormal behavior and sharp weight loss were observed in the high-dose PFOS group. Marked hepatomegaly, renal hypertrophy, and orchioncus in treated groups were in accordance with the viscera–somatic indexes of the liver, kidney, and gonad. Histopathological observation showed that relatively serious damage occurred in the liver and lung, mainly including hepatocytic hypertrophy and cytoplasmic vacuolation in the livers and congestion and thickened epithelial walls in the lungs. PFOA concentrations in main target organs were in the order of kidney > liver > lung > (heart, whole blood) > testicle > (spleen, brain), whereas the bioaccumulation order for PFOS was liver > heart > kidney > (whole blood) > lung > (testicle, spleen, brain). The highest concentration of PFOA detected in the kidney exposed to 5 mg/kg/day was 228 ± 37 μg/g and PFOS in the liver exposed to 20 mg/kg/day reached the highest level of 648 ± 17 μg/g, indicating that the liver, lung, and kidney might serve as the main target organs for PFCs. Furthermore, a dose-dependent accumulation of PFOS in various tissues was found. The accumulation levels of PFOS were universally higher than PFOA, which might explain the relative high toxicity of PFOS. The definite toxicity and high accumulation of the tested PFCs might pose a great threat to biota and human beings due to their widespread application in various fields.     

Carryover of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) from Soil to Plants

Within the scope of a joint project to study soil-to-plant carryover of polyfluorinated compounds (PFCs), five cultivated plants (spring wheat, oats, potatoes, maize, and perennial ryegrass) were sown or planted in Mitscherlich pots. Six variants per species were used, each with a different concentration level of PFOA and PFOS (from 0.25 to 50 mg/kg as aqueous solution) to detect possible concentration dependence in the transfer of these two PFCs from soil to plant. PFOA and PFOS were detected by liquid chromatography-tandem mass spectrometry after appropriate sample preparation (partial drying, mincing, homogenizing, extraction). Since PFOA and PFOS presently represent the most widely studied PFCs, they are classified as “leading compounds.” The results show that concentrations of PFOA/PFOS in the plants vary greatly, depending on the concentrations applied to the soil. PFOA values were higher than PFOS values in all plants except potatoes, in which these differences could be quite substantial. From the results presented here it can be seen that uptake and storage are much more intensive in the vegetative portion of the plant than relocation in the storage organs. This is particularly evident from the the comparison of concentrations found in the grain and ear and those in the straw or rest of the plant in spring wheat, oats, and maize. Transfer from “soil to crops” provides a possible explanation for the presence of PFCs in foodstuffs and in human body fluids such as blood, plasma, serum, or breast milk. The aim of the present study was to determine whether a statistically significant, concentration-dependent carryover of PFOA and PFOS in crop plants can take place, which would provide a potential entrance point for these substances into the food chain.

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Association of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) with Uric Acid among Adults with Elevated Community Exposure to PFOA

Background

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are compounds that do not occur in nature, have been widely used since World War II, and persist indefinitely in most environments. Median serum levels in the United States are 4 ng/mL for PFOA and 21 ng/mL for PFOS. PFOA has been associated with elevated uric acid in two studies of chemical workers. Uric acid is a risk factor for hypertension and possibly other cardiovascular outcomes.

Methods

We conducted a cross-sectional study of PFOA and PFOS and uric acid among 54,951 adult community residents in Ohio and West Virginia, who lived or worked in six water districts contaminated with PFOA from a chemical plant. Analyses were conducted by linear and logistic regression, adjusted for confounders.

Results

Both PFOA and PFOS were significantly associated with uric acid. An increase of 0.2–0.3 mg/dL uric acid was associated with an increase from the lowest to highest decile of either PFOA or PFOS. Hyperuricemia risk increased modestly with increasing PFOA; the odds ratios by quintile of PFOA were 1.00, 1.33 [95% confidence interval (CI), 1.24–1.43], 1.35 (95% CI, 1.26–1.45), 1.47 (95% CI, 1.37–1.58), and 1.47 (95% CI, 1.37–1.58; test for trend, p < 0.0001). We saw a less steep trend for PFOS. Inclusion of both correlated fluorocarbons in the model indicated PFOA was a more important predictor than was PFOS.

Conclusion

Higher serum levels of PFOA were associated with a higher prevalence of hyperuricemia, but the limitations of cross-sectional data and the possibility of noncausal mechanisms prohibit conclusions regarding causality.     

固相萃取富集净化-高效液相色谱串联质谱法测定饮用水中全氟化合物

目的建立固相萃取浓缩与高效液相色谱串联质谱法(HPLC-MS/MS)测定饮用水中全氟辛酸(PFOA)、全氟辛烷磺酸(PFOS)、全氟癸酸(PFDA)等全氟化合物的方法。方法样品经C18固相萃取浓缩净化,应用负离子电喷雾电离,检测方式为多级反应离子监测(MRM)模式,高效液相色谱串联质谱法(HPLC-MS/MS)进行测定。结果PFOA、PFOS、PFDA在50~1000pg/ml线性范围内,线性相关系数均>0.99。在8、20.0pg/g添加水平的回收率为65%~111%,相对标准偏差为3.6%~14.6%(n=6),定量检出限为8pg/g。结论该法适用于饮用水中PFOA、PFOS、PFDA等全氟化合物的测定,具有快速、定量准确、检测灵敏等优点。     

Serum perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) concentrations and liver function biomarkers in a population with elevated PFOA exposure

Background: Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) persist in the environment and are found in relatively high concentrations in animal livers. Studies in humans have reported inconsistent associations between PFOA and liver enzymes.Objectives: We examined the cross-sectional association between serum PFOA and PFOS concentrations with markers of liver function in adults.Methods: The C8 Health Project collected data on 69,030 persons; of these, a total of 47,092 adults were included in the present analysis. Linear regression models were fitted for natural log (ln)-transformed values of alanine transaminase (ALT), γ-glutamyltransferase (GGT), and direct bilirubin on PFOA, PFOS, and potential confounders. Logistic regression models were fitted comparing deciles of PFOA or PFOS in relation to high biomarker levels. A multilevel analysis comparing the evidence for association of PFOA with liver function at the individual level within water districts to that at the population level between water districts was also performed.Results: ln-PFOA and ln-PFOS were associated with ln-ALT in linear regression models [PFOA: coefficient, 0.022; 95% confidence interval (CI): 0.018, 0.025; PFOS: coefficient, 0.020; 95% CI: 0.014, 0.026] and with raised ALT in logistic regression models [with a steady increase in the odds ratio (OR) estimates across deciles of PFOA and PFOS; PFOA: OR = 1.10; 95% CI: 1.07, 1.13; PFOS: OR = 1.13; 95% CI: 1.07, 1.18]. There was less consistent evidence of an association of PFOA and GGT or bilirubin. The relationship with bilirubin appears to rise at low levels of PFOA and to fall again at higher levels.Conclusions: These results show a positive association between PFOA and PFOS concentrations and serum ALT level, a marker of hepatocellular damage.     

Respiratory Uptake and Depuration Kinetics of Perfluorooctanesulfonate (PFOS) in a Marine Sandworm Species

We determined the respiratory uptake and depuration kinetics of perfluorooctanesulfonate (PFOS) in Perinereis wilsoni, a polychaete sandworm used as a model species to investigate the fate of chemical pollutants in coastal environments. The sandworms were kept in gravel-packed containers, and the water levels were varied cyclically to mimic the tides. We used seawater kept at 17.1°C. A 7-day exposure period was followed by a 9-day depuration period. The dissolved PFOS concentration averaged 28 ng/L during the exposure period. Sandworm samples were collected regularly for analysis of PFOS concentrations, and a first-order-kinetics model was applied to the concentrations. The respiratory absorption efficiency of PFOS was estimated to be 11% that of oxygen, which is higher than the corresponding estimates reported for several fish species. The estimated depuration half-life of 15 days was comparable to previously reported estimates for fish and oligochaete species. The bioconcentration factor was 470.     

Disposition of perfluorinated acid isomers in Sprague-Dawley rats; part 2: subchronic dose

Two major industrial synthetic pathways have been used to produce perfluorinated acids (PFAs) or their precursors: Telomerization and electrochemical fluorination (ECF). Products of telomer and ECF origin can be distinguished by structural isomer profiles. A mixture of linear and branched perfluoroalkyl isomers is associated with ECF. Telomer products characteristically consist of a single perfluoroalkyl geometry, typically linear. In biota, it is unclear if the isomer profile is conserved relative to the exposure medium and hence whether PFA isomer profiles in organisms are useful for distinguishing environmental PFA sources. A companion study suggested isomer-specific disposition following a single oral gavage exposure to rats. To confirm these findings under a more realistic subchronic feeding scenario, male and female rats were administered PFA isomers by diet for 12 weeks, followed by a 12-week depuration period. The diet contained 500 ng/g each of ECF perfluorooctanoate (PFOA, approximately 80% n-PFOA), ECF perfluorooctane sulfonate (PFOS, approximately 70% n-PFOS), and linear and isopropyl perfluorononanoate (n- and iso-PFNA). Blood sampling during the exposure phase revealed preferential accumulation of n-PFOA and n-PFNA compared to most branched isomers. Female rats depurated all isomers faster than males. Both sexes eliminated most branched perfluorocarboxylate isomers more rapidly than the n-isomer. Elimination rates of the major branched PFOS isomers were not statistically different from n-PFOS. Two minor isomers of ECF PFOA and one branched PFOS isomer had longer elimination half-lives than the n-isomers. Although extrapolation of these pharmacokinetics trends in rats to humans and wildlife requires careful consideration of dosage level and species-specific physiology, cumulative evidence suggests that perfluorocarboxylate isomer profiles in biota may not be suitable for quantifying the relative contributions of telomer and ECF sources.     

Perfluorinated Compounds in River Water, River Sediment, Market Fish, and Wildlife Samples from Japan

Perfluorinated organic compounds (PFCs) such as PFOS, PFOA, PFBS, PFH×S, PFOSA and PFDoA were determined in river water, river sediment, liver of market fish and liver of wildlife samples from Japan. Concentrations of PFOA and PFOS in water samples were 7.9–110 and <5.2–10 ng/L. Only PFOA were detected in sediment from Kyoto river at 1.3–3.9 ng/g dry wt. Among fish, only jack mackerel showed PFOA and PFOS at 10 and 1.6 ng/g wet wt. Wildlife liver contained PFOSA, PFOS, PFDoA, PFOA and PFH×S in the range of 0.31–362, 0.15–238, <0.03–28, >0.07–7.3 and <0.03–1.5, respectively, on ng/g wet wt. Cormorants showed maximum accumulation followed by eagle, raccoon dog and large-billed crow.     

Negative results of<Emphasis Type="Italic">umu</Emphasis> genotoxicity test of fluorotelomer alcohols and perfluorinated alkyl acids

Objectives  Recently, perfluorooctanoate (PFOA) has been ubiquitously detected in the environment as well as in human serum. Fluorotelomer alcohols (FTOHs), a precursor of PFOA, undergo biodegradation via several metabolic routes which leads to formation of various biodegradation products. The degradation of FTOHs produces an α,β-unsaturated aldehyde that seems possibly to be electrophilic and may react with cellular macromolecules including DNA. Methods  We investigated the genotoxicity of three FTOHs (6∶2 FTOH, 8∶2 FTOH and 10∶2 FTOH), PFOA and perfluorooctane sulfonate (PFOS) using theumu test. Results  The FTOHs, PFOA and PFOS showed no significant increases in β-galactosidase activity at 0–1000 μM in the absence of S9 mix. The results were unchanged by the metabolic activation with S9 mix. Conclusion  The genotoxicities of FTOHs, PFOA or PFOS are not detectable using the present method, suggesting that they are unlikely mutagens.     

Serum concentrations of per- and poly-fluoroalkyl substances and factors associated with exposure in the general adult population in South Korea

Per- and polyfluoroalkyl substances (PFASs) are ubiquitous contaminants found worldwide, including in South Korea. As a result, they are frequently detected in Koreans. However, there is limited representative data and information on potential sources in Korea. Therefore, we measured the serum concentrations of ten PFASs in nationally representative samples of the Korean population (n = 1874, 18–69 years) and evaluated the factors associated with their exposure. Serum PFOS, PFDA, PFOA, and PFNA were detected in nearly all participants (83.1–99.9%). However, serum PFPA, PFHxA, and PFHpA were almost undetected (<0.5% of participants). PFOS had the highest population-weighted geometric mean of 10.23 ng/mL (95% CI: 9.99–10.47), which was followed by PFOA with 2.85 ng/mL (95% CI: 2.73–2.97) and PFDA with 2.17 ng/mL (95% CI: 2.12–2.23). PFNA, PFDA, PFHxS, PFOA, and PFOS concentrations were higher in males (p < 0.001) and older adults (p < 0.001). PFNA was higher in those who used wax, polish, and water-resistant materials (adjusted proportional change = 1.14; 95% CI: 1.08–1.22), and those who ate cooked fish (1.16; 95% CI: 1.03–1.31) compared to those who ate nearly no fish. PFDA was higher in those who used herbicides and pesticides (1.05; 95% CI: 1.02–1.09), those who drank beverages in a plastic bag on a daily basis (1.10; 95% CI: 1.03–1.19), and those who ate raw fish (1.15; 95% CI: 1.03–1.29) or cooked fish (1.13; 95% CI: 1.05–1.23) compared to those who ate nearly no fish. PFHxS was higher in those who used traditional Korean health supplement foods (1.08; 95% CI: 1.01–1.15). PFOA was higher in those who used plastic wrap in a microwave daily or weekly (1.08; 95% CI: 1.00–1.16), and those who used disposable paper cups (1.07; 95% CI: 1.01–1.13). PFOS was lower in underweight participants (0.84; 95%CI: 0.75–0.93) compared to those who were obese, and higher in those who exercised regularly (1.08; 95% CI: 1.03–1.14) or irregularly (1.06, 95% CI: 1.01–1.12) compared to those who did not exercise. Subjects who used severely damaged Teflon appliances had lower concentrations of PFOA (0.78, 95% CI: 0.65–0.95), while regular use of Gore-Tex goods was related to higher PFNA (1.15, 95% CI: 1.03–1.28) and PFDA (1.11; 95% CI: 1.02–1.20) levels. These findings suggest that most Koreans are frequently exposed to PFASs, and that serum concentrations of PFASs vary with age, sex, and exposure factors.     

全氟辛酸和全氟辛烷磺酸经大鼠离体皮肤吸收实验

[目的]探讨全氟辛酸（PFOA）和全氟辛烷磺酸（PFOS）是否能体外经皮吸收及其吸收特征。[方法]采用Franz扩散装置,以10μmol／L的PFOA和PFOS的混合溶液（1：1）作为供体液,用HPLC．MS测定两种化合物的单位面积SD大鼠离体皮肤的累积渗透量,分别计算其稳态渗透速率、渗透滞后时间和渗透系数。[结果]各透过时间点受体液中均可检测到PFOA和PFOS;PFOA和PFOS的12h累积渗透量分别为（4．97±1．80）、（1．76±1．06）μg/cm2,稳态渗透速率分别为（0．48±0．19）、（0．16±0．06）μg／cm2·h,渗透滞后时间分别为（0．31±0．18）、（0．50±0．06）h,渗透系数分别为（11．48±4．51）×10^-2、（3．17±1．22）×10^-2cm／h。[结论]PFOA和PFOS均能够经皮吸收,前者稳态渗透快于后者,渗透系数大于后者,渗透滞后时间明显小于后者。该研究确定了PFOA和PFOS的体外经皮吸收特征,为暴露量评定和危险性评价提供了有意义的基础研究数据。     

Toxicity of perfluorooctane sulfonic acid and perfluorooctanoic acid on freshwater macroinvertebrates (Daphnia magna and Moina macrocopa) and fish (Oryzias latipes)

Because of their global distribution, persistence, and tendency to bioaccumulate, concerns about perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are growing. We determined the toxicity of PFOS and PFOA in several freshwater organisms, including two cladocerans, Daphnia magna and Moina macrocopa, and the teleost Oryzias latipes. In general, PFOS is approximately 10 times more toxic than PFOA in these organisms. In M. macrocopa, the median lethal concentration (LC50) was 17.95 mg/L for PFOS and 199.51 mg/L for PFOA. Moina macrocopa exhibited greater sensitivity than D. magna to both perfluorinated compounds in both acute and chronic exposures. In the 48-h acute toxicity test, M. macrocopa was approximately two times more sensitive than D. magna. In the 7-d chronic toxicity test, M. macrocopa showed significant reproductive changes at 0.31 mg/L for PFOS, which was approximately seven times lower than the effect concentrations observed over the 21-d exposure in D. magna. Two-generation fish toxicity tests showed that parental exposure to both compounds affected the performance of offspring. Unexposed progeny-generation (F1) fish exhibited elevated mortality and histopathological changes that were correlated with exposure in the parental generation (F0). Continuous exposure from F0 through F1 generations increased the extent of adverse effects. Considering the persistent nature of PFOS and PFOA, more research is required to determine potential consequences of long-term exposure to these compounds in aquatic ecosystems.