The Total Mass of Per- and Polyfluoroalkyl Substances (PFASs) in California Cosmetics.

Cosmetics make up one of the consumer product categories most widely known to contain perfluoroalkyl and polyfluoroalkyl substances (PFASs), including precursors to perfluorooctanoic acid (PFOA) and other perfluoroalkyl acids (PFAAs). Because of the way cosmetics are used, most of the PFASs present in these products are likely to reach wastewater treatment plants (WWTPs), which suggests that cosmetics may contribute significantly to the load of PFOA and other PFASs at WWTPs. However, the majority of PFASs present as intentional ingredients in cosmetics cannot be quantified with the available analytical methods. To address this issue, we developed a methodology to estimate the total PFAS mass in cosmetics as well as the corresponding mass of total organic fluorine and of fluorinated side chains associated with PFAA precursors, using various ingredient databases and ingredient concentrations reported by manufacturers. Our results indicate that the cosmetics sold in California during a one-year period cumulatively contain 650-56 000 kg of total PFASs, 370-37 000 kg of organic fluorine, and 330-20 000 kg of fluorinated side chains associated with PFAA precursors. Among the 16 product subcategories considered, >90% of the PFAS mass came from shaving creams and gels, hair care products, facial cleansers, sun care products, and lotions and moisturizers, while the sum of all nine makeup subcategories accounted for <3%. Comparing our estimates to available WWTP influent data from the San Francisco Bay Area suggests that cosmetics may account for at least 4% of the precursor-derived PFAAs measured in wastewater. As the first study ever to estimate the total mass of PFASs contained in cosmetics sold in California, our results shed light on the significance of certain cosmetics as a source of PFASs to WWTPs and can inform effective source reduction efforts.

Can on-site leachate treatment facilities effectively address the issue of perfluoroalkyl acids (PFAAs) in leachate?

In recent decades, the presence of perfluoroalkyl acids (PFAAs) in municipal solid waste leachate has emerged as a growing concern. Research has focused on PFAA release and occurrence characteristics in landfill and waste-to-energy leachate, highlighting their significant impact when released into wastewater treatment plants. Given the extremely high loading rate faced by current on-site leachate treatment plants (LTPs), the objective of this study is to assess whether the current "anaerobic/aerobic (A/O) + membrane bioreactor (MBR) + nanofiltration (NF) + reverse osmosis (RO)" configuration is effective in PFAAs removal. Concentrations of raw and treated leachate in 10 on-site LTPs with same treatment configuration and varying landfill ages were measured, and a comprehensive mass flow analysis of each treatment process was conducted. The results indicate that A/O treatment has limited capacity for PFAA removal, while NF and RO processes reached 77.44 % and 94.30 % removal rates of ∑PFAAs concentration, respectively. Short-chain PFAAs (> 80 % detected frequency) primarily influenced the distribution and variations of PFAAs in leachate and tend to disperse in the water phase. Correlation analysis revealed the current on-site LTPs exhibit a more efficient removal capacity for long-chain PFAAs.

Removal of perfluoroalkyl acids (PFAAs) from aqueous solution by water hyacinth (Eichhornia crassipes): Uptake, accumulation, and translocation.

Although Eichhornia crassipes, commonly known as water hyacinth, has been widely used in wastewater treatment, further investigations are still needed to explore the removal efficiency of perfluoroalkyl acids (PFAAs) from the aqueous environment using this floating aquatic plant. In this study, a hydroponic experiment was conducted to assess accumulation, bioconcentration factors (BCFs), translocation factors (TFs), and removal rates of eight PFAAs by water hyacinth. The obtained results indicated that all PFAAs, including five perfluoroalkyl carboxylic acids (PFCAs) with chain lengths C4-C8 and three perfluoroalkyl sulfonic acids (PFSAs) with C4, C6, and C8, were readily accumulated in water hyacinth. Throughout the duration of the experiment, there was a noticeable increase in PFAA concentrations and BCF values for different plant parts. For the root, PFAAs with more carbon numbers showed a higher uptake than the shorter homologues, with PFSAs being more readily accumulated compared to PFCAs with the same carbon number in the molecules. In contrast, the levels of long-chain PFAAs were comparatively lower than those of short-chain substances in the stem and leaf. Notably, PFAAs with less carbon numbers, like PFPeA, PFBA, and PFBS, showed a remarkable translocation from the root to the stem and leaf with TFs >1. For the whole plant, no significant correlation was found between BCFs and organic carbon-water partition coefficients (Koc), octanol-water partition coefficients (Kow), membrane-water distribution coefficients (Dmw), or protein-water distribution coefficients (Dpw). The removal rates of PFAAs ranged from 40.3 to 63.5 % throughout the three weeks of the experiment while the removal efficiencies varied from 48.9 % for PFHxS to 82.6 % for PFPeA in the last week.

A systematic review on distribution, sources and sorption of perfluoroalkyl acids (PFAAs) in soil and their plant uptake.

Perfluoroalkyl acids (PFAAs) are ubiquitous in environment, which have attracted increasing concerns in recent years. This study collected the data on PFAAs concentrations in 1042 soil samples from 15 countries and comprehensively reviewed the spatial distribution, sources, sorption mechanisms of PFAAs in soil and their plant uptake. PFAAs are widely detected in soils from many countries worldwide and their distribution is related to the emission of the fluorine-containing organic industry. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are found to be the predominant PFAAs in soil. Industrial emission is the main source of PFAAs contributing 49.9% of the total concentrations of PFAAs (Æ© PFAAs) in soil, followed by activated sludge treated by wastewater treatment plants (WWTPs) (19.9%) and irrigation of effluents from WWTPs, usage of aqueous film-forming foam (AFFFs) and leaching of leachate from landfill (30.2%). The adsorption of PFAAs by soil is mainly influenced by soil pH, ionic strength, soil organic matter and minerals. The concentrations of perfluoroalkyl carboxylic acids (PFCAs) in soil are negatively correlated with the length of carbon chain, log Kow, and log Koc. The carbon chain lengths of PFAAs are negatively correlated with the root-soil concentration factors (RCFs) and shoot-soil concentration factors (SCFs). The uptake of PFAAs by plant is influenced by physicochemical properties of PFAAs, plant physiology and soil environment. Further studies should be conducted to make up the inadequacy of existing knowledge on the behavior and fate of PFAAs in soil-plant system.

[Advances in Microbial Degradation and Transformation of Per- and Polyfluoroalkyl Substances(PFASs)].

Per- and polyfluoroalkyl substances (PFASs) have attracted extensive attention because of their persistence, long-distance migration ability, bioaccumulation, and biological toxicity. Currently, regulatory strategies concerning PFASs in the environment primarily focus on perfluoroalkyl acids (PFAAs). However, most polyfluoroalkyl compounds can be degraded to PFAAs by environmental microorganisms, also known as precursors. Exploring the microbial transformation behavior of precursors is fundamental to comprehensively evaluate the environmental risk of PFASs and formulate control and remediation schemes of PFAS-contaminated sites. Furthermore, anaerobic microbial reductive defluorination of PFAAs is a potential and challenging remediation technology. This review summarizes degradation rules and transformation pathways of precursors (fluorotelomer compounds and perfluorooctane sulfonamide derivatives), PFAAs, and novel PFASs by microorganisms and discusses factors affecting the microbial degradation. Finally, the future research directions are put forward.

Confirming sulfluramid (EtFOSA) application as a precursor of perfluorooctanesulfonic acid (PFOS) in Brazilian agricultural soils.

Perfluorooctanesulfonic acid (PFOS) is a manmade chemical with several industrial applications and also a potential byproduct of many other per- and polyfluorinated substances (PFAS) in the environment. Due to the gathered evidence on its environmental persistence, long-range transport, toxicity, and bioaccumulative and biomagnifying properties, PFOS, its salts and perfluorooctane sulfonyl fluoride (PFOSF), were listed for global restriction under the Stockholm Convention on Persistent Organic Pollutants in 2009. Nevertheless, Brazil has granted an acceptable purpose exemption for using PFOSF to produce sulfluramid (EtFOSA) and to apply it as insecticide to control leaf-cutting ants of the genus Atta and Acromyrmex. Previous studies have pointed out EtFOSA as a precursor of PFOS in the environment, including in soils. Therefore, we aimed to confirm the role of EtFOSA in PFOS formation in soils representing areas where sulfluramid-based ant baits are used. A biodegradation assay was carried out by applying technical EtFOSA in triplicate samples of ultisol (PV) and oxisol (LVd) and measuring the contents of EtFOSA, perfluorooctane sulfonamide acetic acid (FOSAA), perfluorooctane sulfonamide (FOSA), and PFOS at seven moments (0, 3, 7, 15, 30, 60, and 120 days). The monitored byproducts started being noticed on the 15th day. After 120 days, PFOS yields were 30% for both soils, whereas FOSA yields were 46% (PV soil) and 42% (LVd soil) and FOSAA yields were 6% (PV soil) and 3% (LVd soil). It can be expected that FOSAA and FOSA contents will eventually be converted into PFOS in the environment and that the presence of plants could boost PFOS formation. Therefore, the ongoing extensive and intensive use of sulfluramid-based ant baits pose a considerable source of PFOS to the environment.

An unexpected synergistic toxicity caused by competitive bioconcentration of perfluoroalkyl acid mixtures to Daphnia magna: Further promoted by elevated temperature.

The mixed pollution of the global water environment by perfluoroalkyl acids (PFAAs) and their ecological risks have aroused widespread concern. However, the relationship between the combined toxicity of PFAA mixtures and their accumulation in aquatic organisms is not well understood in the context of global warming. Here, we study the bioconcentration and combined toxicity of three PFAA mixtures (PFOA, PFDA, PFDoA) to Daphnia magna (D. magna) under different exposure concentrations and temperatures. The results show that although competitive bioconcentration exists, the combined toxicity of the PFAA mixtures to D. magna is synergistic. These contradictory phenomena occur because although the longer-chain PFDoA inhibits the bioconcentration of the shorter-chain PFOA and PFDA, the bioconcentration of PFDoA itself is promoted, and PFDoA is more toxic to D. magna than PFOA and PFDA. The toxic equivalent concentration for the PFAA mixture is 1.38-1.67 times higher than that obtained from simple addition for the three PFAAs when exposed separately. Moreover, elevated temperature promotes not only the bioconcentration of each PFAA and the competition of bioconcentration between shorter-chain and longer-chain PAFF, but also the synergistic toxicity of PFAA mixtures to D. magna. This study suggests that the effect of the interactions among different PFAAs on their bioconcentration and toxicity under different water environmental conditions, such as temperature, should be considered for ecological risk assessment of PFAA mixtures.

Per- and polyfluoroalkyl substance (PFAS) retention by colloidal activated carbon (CAC) using dynamic column experiments.

Developing effective remediation methods for per- and polyfluoroalkyl substance (PFAS)-contaminated soils is a substantial step towards counteracting their widespread occurrence and protecting our ecosystems and drinking water sources. Stabilisation of PFAS in the subsurface using colloidal activated carbon (CAC) is an innovative, yet promising technique, requiring better understanding. In this study, dynamic soil column tests were used to assess the retardation of 10 classical perfluoroalkyl acids (PFAAs) (C5-C11 perfluoroalkyl carboxylic acids (PFCAs) and C4, C6, C8 perfluoroalkane sulfonates (PFSAs)) as well as two alternative PFAS (6:2 and 8:2 fluorotelomer sulfonates) using CAC at 0.03% w/w, to investigate the fate and transport of PFAS under CAC treatment applications. Results showed high retardation rates for long-chain PFAS and eight times higher retardation for the CAC-treated soil compared to the non-treated reference soil for the ∑PFAS. Replacement of shorter chain perfluorocarboxylic acids (PFCAs), such as perfluoropentanoic acid (PFPeA), by longer chained PFAS was observed, indicating competition effects. Partitioning coefficients (Kd values) were calculated for the CAC fraction at ∼103-105 L kg-1 for individual PFAS, while there was a significant positive correlation (p < 0.05) between perfluorocarbon chain length and Kd. Mass balance calculations showed 37% retention of ∑PFAS in treated soil columns after completion of the experiments and 99.7% higher retention rates than the reference soil. Redistribution and elution of CAC were noticed and quantified through organic carbon analysis, which showed a 23% loss of carbon during the experiments. These findings are a step towards better understanding the extent of CAC's potential for remediation of PFAS-contaminated soil and groundwater and the limitations of its applications.

Sea Spray Aerosol (SSA) as a Source of Perfluoroalkyl Acids (PFAAs) to the Atmosphere: Field Evidence from Long-Term Air Monitoring.

The effective enrichment of perfluoroalkyl acids (PFAAs) in sea spray aerosols (SSA) demonstrated in previous laboratory studies suggests that SSA is a potential source of PFAAs to the atmosphere. In order to investigate the influence of SSA on atmospheric PFAAs in the field, 48 h aerosol samples were collected regularly between 2018 and 2020 at two Norwegian coastal locations, Andøya and Birkenes. Significant correlations (p < 0.05) between the SSA tracer ion, Na+, and PFAA concentrations were observed in the samples from both locations, with Pearson's correlation coefficients (r) between 0.4-0.8. Such significant correlations indicate SSA to be an important source of atmospheric PFAAs to coastal areas. The correlations in the samples from Andøya were observed for more PFAA species and were generally stronger than in the samples from Birkenes, which is located further away from the coast and closer to urban areas than Andøya. Factors such as the origin of the SSA, the distance of the sampling site to open water, and the presence of other PFAA sources (e.g., volatile precursor compounds) can have influence on the contribution of SSA to PFAA in air at the sampling sites and therefore affect the observed correlations between PFAAs and Na+.

Uptake and translocation of perfluoroalkyl acids with different carbon chain lengths (C2-C8) in wheat (Triticum acstivnm L.) under the effect of copper exposure.

The co-contamination by perfluoroalkyl acids (PFAAs) and heavy metals (HMs) is ubiquitous in the surface environment subjected to sewage irrigation and land application of sludge. However, the joint effects of HMs and PFAAs on plant roots are not well clarified. This study explored the root uptake and acropetal translocation behaviors of C2-C8 PFAAs by wheat (Triticum acstivnm L.) under the co-exposure of copper (Cu). The underlying uptake mechanisms of PFAAs were verified in a defective root system. The results showed that excessive Cu (100-400 µmol/L) damaged the cell membrane of wheat root to increase electrolytic leakage. In the defective root system, the root concentrations of PFAAs decreased by 6%-73% and the decrease rates were negatively associated with the carbon chain length of PFAAs. Along with the decrease in root concentrations of PFAAs, the amount of ultrashort-chain (C2-C3) and short-chain (C4-C6) PFAAs translocated to the shoot also decreased by 45%-84%. In contrast, the acropetal translocation of long-chain (C8) PFAAs, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), was enhanced under Cu exposure due to the increase in root permeability as observed by increased electrolytic leakage. The shoot concentrations of PFOA and PFOS under Cu exposure were up to 5.5 and 11 times higher than those in the control, respectively. These results suggested that PFOA and PFOS could enter wheat root more easily through the breaks caused by Cu exposure and thereby their acropetal transportation to shoot was enhanced. Therefore, the risk of plant accumulation of long-chain PFAAs can be potentially underestimated if without considering the co-contamination with HMs in the environment.

Comparisons of tissue distributions and health risks of perfluoroalkyl acids (PFAAs) in two fish species with different trophic levels from Lake Chaohu, China.

Perfluoroalkyl acids (PFAAs) are a type of persistent organic pollutants that are widely distributed in multiple environmental media and organisms and have a teratogenic effect on and toxicity to animals and humans. The residual levels of seventeen PFAAs in the tissues of two regular consumption fish species, Culter erythropterus and Aristichthys nobilis in Lake Chaohu were measured by a high-performance liquid chromatograph - mass spectrometer (HPLC-MS). The distributions of PFAAs and the effect of the lipid contents were analyzed, and the health risks of typical PFAAs were evaluated. The results showed that perfluorohexanoic acid (PFHxA) was the predominant contaminant (80.50 ±â€¯58.31 ng/g and 19.17 ±â€¯12.57 ng/g wet weight, ww), followed by perfluorooctanesulfonic acid (PFOS) (55.02 ±â€¯34.82 and 14.79 ±â€¯6.24 ng/g, ww) in both fish. The level of total PFAAs was the highest in the liver tissues of Culter erythropterus (359.87 ng/g, ww) and the lowest in the kidney tissues in A. nobilis (10.06 ng/g, ww). Due to the higher trophic level of C. erythropteru, the total PFAA concentrations were significantly higher in all tissues than those in A. nobilis. Liver muscle ratio of C. erythropteru was the highest, indicating the most accumulation in the liver. The concentrations of PFAAs in fish tissues were influenced by the lipid content, resulting in a difference between the lipid-normalized concentrations and the wet weight concentrations of the PFAAs. The non-carcinogenic risks of PFOS were higher than those of PFOA through the ingestion of C. erythropterus and A. nobilis. Both the carcinogenic and non-carcinogenic risks of C. erythropterus were greater than those of A. nobilis, and fish tissue intake could cause an increasing of risks up to 60%, indicating that long-term and large amount ingestion of carnivorous fish and related tissues with higher trophic level, such as C. erythropterus should be avoided.

Occurrence and human exposure assessment of perfluorinated substances in house dust from three European countries.

65 house dust samples from three European countries (Belgium, Italy and Spain) were evaluated for the presence of 20 polyflouroalkyl substances (PFASs) including perfluoroalkane sulfonic acids (PFSAs), perfluoroalkyl carboxylic acid (PFCAs) and perfluoroalkane sulfonamides (PFOSAs). The three countries presented similar PFAS levels ranging from 3.13 to 155 ng/g (12.9 ng/g; median), but in all cases PFCAs concentrations (6.92, 15.2 and 8.68 ng/g; median for Belgium, Italy and Spain) were higher than those obtained for PFSAs (2.30, 1.76 and 2.68 ng/g). Interestingly, in comparison to previously published data exhibited an increase in perfluorobutanesulfonate (PFBS) concentrations in Belgian house dust. On the other hand, levels of perfluorooctanesulfonate (PFOS) decreased in Spanish case. Data were examined for relationships between PFAS house dust levels, building and outdoor surrounding characteristics and occupant habits. Main findings revealed a positive association between PFOS concentrations and the building edification age, which could highlight a decrease in the use of this chemical in Europe. Similarly, perfluorohexanesulfonate (PFHxS) levels correlated with the percentage of the floor covered by textiles. Homes located in industrial sites showed higher PFCA levels compared to urban or agricultural locations, revealing the industrial processes as a potential source of these chemicals in Europe. Data obtained were used to perform human exposure assessment for dust intake via oral ingestion. Estimated daily intakes, calculated for toddlers and adults at median and worst case scenarios, were below oral Reference Dose (RfD) and tolerable daily intakes (TDI). However, in perfluorooctanoic acid (PFOA) case, dust ingestion significance to total dietary exposure reached values of 51% for toddlers in the worst case scenario.

Environmental perfluoroalkyl acid exposures are associated with liver disease characterized by apoptosis and altered serum adipocytokines.

Exposures to perfluoroalkyl substances (PFAS) including perfluoroalkyl acids (PFAAs) are associated with increased liver enzymes in cohort studies including the C8 Health Study. In animal models, PFAAs disrupt hepatic lipid metabolism and induce apoptosis to cause nonalcoholic fatty liver disease (NAFLD). PFAAs are immunotoxic and inhibit pro-inflammatory cytokine release from stimulated leukocytes in vitro. This cross-sectional study tests the hypothesis that environmental PFAAs are associated with increased hepatocyte apoptosis and decreased pro-inflammatory cytokines in serum. Biomarkers previously associated with PFAS exposures and/or NAFLD were evaluated as secondary endpoints. Two hundred adult C8 Health Study participants were included. Measured serum biomarkers included: perfluorohexane sulfonate (PFHxS); perfluorooctanoic acid (PFOA); perfluorooctane sulfonate (PFOS); perfluorononanoic acid (PFNA); cytokeratin 18 M30 (CK18 M30, hepatocyte apoptosis); adipocytokines; insulin; and cleaved complement 3 (C3a). Confounder-adjusted linear regression models determined associations between PFAS and disease biomarkers with cut-offs determined by classification and regression tree analysis. CK18 M30 was positively associated with PFHxS (ß = 0.889, p = 0.042); PFOA (ß = 2.1, p = 0.005); and PFNA (ß = 0.567, p = 0.03). Tumor necrosis factor α (TNFα) was inversely associated with PFHxS (ß = -0.799, p = 0.001); PFOA (ß = - 1.242, p = 0.001); and PFOS (ß = -0.704, p < 0.001). Interleukin 8 was inversely associated with PFOS and PFNA. PFAAs were also associated with sexually dimorphic adipocytokine and C3a responses. Overall, PFAA exposures were associated with the novel combination of increased biomarkers of hepatocyte apoptosis and decreased serum TNFα. These data support previous findings from cohorts and experimental systems that PFAAs may cause liver injury while downregulated some aspects of the immune response. Further studies of PFAAs in NAFLD are warranted and should evaluate sex differences.

Uptake mechanisms of perfluoroalkyl acids with different carbon chain lengths (C2-C8) by wheat (Triticum acstivnm L.).

Organic compounds could be taken up by plants via different pathways, depending on chemical properties and biological species, which is important for the risk assessment and risk control. To investigate the transport pathways of perfluoroalkyl acids (PFAAs) by wheat (Triticum acstivnm L.), the uptake of five perfluoroalkyl carboxylic acids (PFCAs): TFA (C2), PFPrA (C3), PFBA (C4), PFHxA (C6), PFOA (C8), and a perfluoroalkyl sulfonic acid: PFOS (C8)) were studied using hydroponic experiments. Various inhibitors including a metabolic inhibitor (Na3VO4), two anion channel blockers (9-AC, DIDS), and two aquaporin inhibitors (AgNO3, glycerol) were examined. The wheat root and shoot showed different concentration trends with the carbon chain length of PFAAs. The uptake of TFA was inhibited by Na3VO4 and 9-AC whereas PFPrA was inhibited by Na3VO4, AgNO3 and 9-AC. For the other four PFAAs, only Na3VO4 was effective. These results together with the result of concentration-dependent uptake, which followed the Michaelis-Menten model, indicate that the uptake of PFAAs by wheat is mainly an energy-dependent active process mediated by carriers. For the ultra-short chain PFCAs (C2 and C3), aquaporins and anion channels may also be involved. A competition between TFA and PFPrA was determined during the plant uptake but no competition was observed between these two shorter chain analogues with other analogues, neither between PFBA and PFHxA, PFBA and PFBS, PFOA and PFOS.

Factors associated with exposure of pregnant women to perfluoroalkyl acids in North China and health risk assessment.

Perfluoroalkyl acids (PFAAs) have been frequently found in blood of pregnant women, but the predictors and potential health risk have not been well studied in China. We recruited 534 pregnant women in Tangshan City of Hebei Province in North China between 2013 and 2014 and measured five PFAAs in serum during their early term of pregnancy, including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), perfluoro­n­undecanoic acid (PFUdA), and perfluorononanoic acid (PFNA). We explored the factors associated with the levels of serum PFAAs and assessed associated health risks. Food consumption information was obtained by food frequency questionnaire covering 100 items. Multiple linear regression model was used to determine the associations of sociodemographic, anthropometric, and food factors with the concentrations of serum PFAAs. Some PFAAs in serum were positively associated with age and body mass index (BMI). Consumption of beans, aquatic products, and eggs was positively associated with the concentrations of several PFAAs after adjusting for important covariates. Pregnant women who ate more cereal, vegetables, mushrooms and alga tended to have lower levels of serum PFOA, PFOS and PFNA. The Hazard index (HI) for reproductive toxicity and developmental toxicity was below 0.8, and the HI for hepatotoxicity beyond 1 was found in 0.37% of pregnant women. These results suggested that age, BMI, and some food consumption were predictors for the exposure to PFAAs in Chinese pregnant women. More attention should be paid to the hepatotoxicity for these exposures.

Effects of combined exposure to perfluoroalkyl acids and heavy metals on bioaccumulation and subcellular distribution in earthworms (Eisenia fetida) from co-contaminated soil.

The effects of combined exposure to perfluoroalkyl acids (PFAAs) and heavy metals (HMs) including cadmium (Cd), copper (Cu), zinc (Zn), nickel (Ni), and lead (Pb) on earthworms (Eisenia fetida) were investigated. The results have demonstrated that the concentrations of labile acid exchangeable Cd, Zn, Ni, Pb, and Cu in soil were enhanced in addition of PFAAs. With PFAAs, the uptake of Cd, Zn, Ni, Pb, and Cu in earthworms was increased compared to those without PFAAs with the order of Cd > Zn > Pb > Ni > Cu. In the presence of HMs, the average biota-to-soil accumulation factors (BSAFs) of PFAAs in earthworms were decreased by 0.498-0.729 times for perfluorooctane sulfonate (PFOS) and 0.606-0.978 times for perfluorooctanoic acid (PFOA), indicating decrease rates of PFOS were higher than those of PFOA. And different levels of HMs led to insignificant different responses on the inhibiting effects of PFAAs uptake in earthworms. The increase of Cd in fraction C (associated with cytosol) and decrease of PFAAs in fraction C and fraction P (associated with tissue fragments, cell membranes, and intact cells) especially for fraction C were revealed when they were combined, suggesting cytosolic PFAAs and Cd were susceptibly mutual effected. This study indicated that PFAAs and metals mutually affected their bioaccumulation and subcellular distribution in earthworms, which will help to understand the fate and risks of PFAAs and metals in co-contaminated soil.

Perfluoroalkyl acids in serum of Korean children: Occurrences, related sources, and associated health outcomes.

Perfluoroalkyl acids (PFAAs) have been widely used in human environment, and their exposure among general population has been frequently reported. However, extent of PFAAs exposure and their potential effects among children are not well characterized. In this study, children of between 3 and 18 years of age (n = 150) were recruited in Seoul and Gyeonggi, Korea, and the serum levels of 16 PFAAs along with lipids and thyroid hormones were measured. Questionnaire survey was conducted for dietary and behavioral characteristics of the children. Among the measured PFAAs, PFOA, PFNA, PFHxS, and PFOS were detected in all the samples, and PFUnDA and PFDA were detected in over 75% of the samples. PFOS was detected at the highest concentration with a median of 5.68 ng/mL. PFUnDA was detected at higher levels (median of 0.652 ng/mL) compared to those reported for children in USA. Serum PFAA levels were not different by sex among the children of <10 years of age, but in older children, those of boys are significantly higher than girls. Physiological characteristics like menstruation may explain lower PFAAs levels of the girls. In addition, breastmilk consumption, fish/shellfish consumption, non-stick frying pan use, and waterproof cloth use were identified as potential sources of PFAAs exposure. Serum PFUnDA level was positively associated with total cholesterol and low-density lipoprotein level of the children. PFNA was positively associated with free T4 level. High levels of PFUnDA among children and its association with serum lipids warrant replication and confirmation in other populations and/or supports by experimental studies.

[Contamination Levels and Exposure Risk via Drinking Water from Perfluoroalkyl Acids in Seven Major Drainage Basins of China].

To study the perfluoroalkyl acid (PFAAs) contamination in seven major drainage basins of China and the exposure risk to resident populations via drinking water sourced from these basins, a risk assessment model of the US EPA and a scenario-based risk assessment method were applied to analyze the PFAA pollution characteristics and to evaluate the average daily dose and health risk to adults, adolescents, and children. In the intermediate-exposure scenario, results showed that the ∑PFAAs median for the seven major drainage basins was 14 ng·L-1, with perfluorooctanoic acid (PFOA), perfluorobutanoic acid (PFBA), and perfluorooctane sulfonic acid (PFOS) the main contaminants, and that the contamination levels were the highest in the Songliao River and Taihu Lake basins. In the high-exposure scenario, the discharge proportion of perfluoroalkyl carboxylic acids with ≤ 6 carbon chains among the ∑PFAAs was higher than that in the intermediate-exposure scenario. In addition, certain sections tended to be more polluted than others in the Yellow River and Yangtze River basins. Risk assessment showed that PFOA and PFOS exposure via drinking water posed no health risk to Chinese residents, and that the average daily ingestion of drinking water of Chinese adolescents was below the suggested amount.

One-pot polymerization of monolith coated stir bar for high efficient sorptive extraction of perfluoroalkyl acids from environmental water samples followed by high performance liquid chromatography-electrospray tandem mass spectrometry detection.

In this work, poly(1-vinylimidazole-ethyleneglycol dimethacrylate) (poly(VI-EDMA)) monolith coated stir bars were synthesized by one-pot polymerization, and they exhibited higher extraction efficiency and faster extraction dynamics for selected PFAAs than commercial ethylene glycol modified silicone (EG-silicone) and polydimethylsiloxane (PDMS) coated stir bars. Taking eleven PFAAs as target analytes, including C4-C12 perfluoroalkyl carboxylates (PFCAs) and C6, C8 perfluoroalkane sulfonates (PFSAs), a method combining monolith-based stir bar sorptive extraction (SBSE) with high performance liquid chromatography (HPLC) - electrospray tandem mass spectrometry (ESI-MS/MS) was proposed for the determination of multiplex PFAAs in environmental water samples. Under the optimized conditions, low limits of detection (0.06-0.40 ng/L) and wide linear range (0.6-400 ng/L) were obtained for target PFAAs with. The developed method was then applied for the analysis of target PFAAs in environmental water samples, and recoveries of 80.1-117% and 80.3-122% were obtained for target PFAAs in spiked Yangtze River and East Lake water samples respectively.

The occurrence, exposure and risk assessment of perfluoroalkyl acids in food from mainland, China.

To study the contamination of perfluoroalkyl acids (PFAAs) in Chinese food and the risk of dietary exposure for the Chinese population, the data of 17 PFAAs covering 38 cities throughout China in 15 groups of foods were collected for meta-analysis from published and available research literature. Using food consumption and body weight parameters, estimated dietary intakes (EDIs) were calculated for evaluation using the Scenario-Based Risk Assessment (SceBRA) modelling. Among food groups, the highest ΣPFAAs concentrations and EDI contributions were both found in poultry (363 ng/g), fish and shrimp (313 ng/g), dark vegetables (309 ng/g), fruits (116 ng/g) and pork (25 ng/g). The EDI of adults in the high-exposure scenario was about twice that of the intermediate-exposure scenario, while the EDI of children was about twice that of adults' EDI in the intermediate-exposure scenario. In addition, the PFOS EDI for children under high exposure approached its tolerable daily intake (TDI). Therefore high dietary exposure to PFAAs is giving rise to an increased health risk, especially for children.