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1.
Environ Sci Technol ; 58(15): 6616-6627, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38569050

RESUMO

While the extent of environmental contamination by per- and polyfluoroalkyl substances (PFAS) has mobilized considerable efforts around the globe in recent years, publicly available data on PFAS in Europe were very limited. In an unprecedented experiment of "expert-reviewed journalism" involving 29 journalists and seven scientific advisers, a cross-border collaborative project, the "Forever Pollution Project" (FPP), drew on both scientific methods and investigative journalism techniques such as open-source intelligence (OSINT) and freedom of information (FOI) requests to map contamination across Europe, making public data that previously had existed as "unseen science". The FPP identified 22,934 known contamination sites, including 20 PFAS manufacturing facilities, and 21,426 "presumptive contamination sites", including 13,745 sites presumably contaminated with fluorinated aqueous film-forming foam (AFFF) discharge, 2911 industrial facilities, and 4752 sites related to PFAS-containing waste. Additionally, the FPP identified 231 "known PFAS users", a new category for sites with an intermediate level of evidence of PFAS use and considered likely to be contamination sources. However, the true extent of contamination in Europe remains significantly underestimated due to a lack of comprehensive geolocation, sampling, and publicly available data. This model of knowledge production and dissemination offers lessons for researchers, policymakers, and journalists about cross-field collaborations and data transparency.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Poluição Ambiental , Europa (Continente) , Comércio
2.
Environ Sci Technol ; 57(48): 19066-19077, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37943968

RESUMO

Pollution by chemicals and waste impacts human and ecosystem health on regional, national, and global scales, resulting, together with climate change and biodiversity loss, in a triple planetary crisis. Consequently, in 2022, countries agreed to establish an intergovernmental science-policy panel (SPP) on chemicals, waste, and pollution prevention, complementary to the existing intergovernmental science-policy bodies on climate change and biodiversity. To ensure the SPP's success, it is imperative to protect it from conflicts of interest (COI). Here, we (i) define and review the implications of COI, and its relevance for the management of chemicals, waste, and pollution; (ii) summarize established tactics to manufacture doubt in favor of vested interests, i.e., to counter scientific evidence and/or to promote misleading narratives favorable to financial interests; and (iii) illustrate these with selected examples. This analysis leads to a review of arguments for and against chemical industry representation in the SPP's work. We further (iv) rebut an assertion voiced by some that the chemical industry should be directly involved in the panel's work because it possesses data on chemicals essential for the panel's activities. Finally, (v) we present steps that should be taken to prevent the detrimental impacts of COI in the work of the SPP. In particular, we propose to include an independent auditor's role in the SPP to ensure that participation and processes follow clear COI rules. Among others, the auditor should evaluate the content of the assessments produced to ensure unbiased representation of information that underpins the SPP's activities.


Assuntos
Conflito de Interesses , Ecossistema , Humanos , Poluição Ambiental , Biodiversidade
3.
Environ Sci Technol ; 56(16): 11172-11179, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35916421

RESUMO

It is hypothesized that environmental contamination by per- and polyfluoroalkyl substances (PFAS) defines a separate planetary boundary and that this boundary has been exceeded. This hypothesis is tested by comparing the levels of four selected perfluoroalkyl acids (PFAAs) (i.e., perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexanesulfonic acid (PFHxS), and perfluorononanoic acid (PFNA)) in various global environmental media (i.e., rainwater, soils, and surface waters) with recently proposed guideline levels. On the basis of the four PFAAs considered, it is concluded that (1) levels of PFOA and PFOS in rainwater often greatly exceed US Environmental Protection Agency (EPA) Lifetime Drinking Water Health Advisory levels and the sum of the aforementioned four PFAAs (Σ4 PFAS) in rainwater is often above Danish drinking water limit values also based on Σ4 PFAS; (2) levels of PFOS in rainwater are often above Environmental Quality Standard for Inland European Union Surface Water; and (3) atmospheric deposition also leads to global soils being ubiquitously contaminated and to be often above proposed Dutch guideline values. It is, therefore, concluded that the global spread of these four PFAAs in the atmosphere has led to the planetary boundary for chemical pollution being exceeded. Levels of PFAAs in atmospheric deposition are especially poorly reversible because of the high persistence of PFAAs and their ability to continuously cycle in the hydrosphere, including on sea spray aerosols emitted from the oceans. Because of the poor reversibility of environmental exposure to PFAS and their associated effects, it is vitally important that PFAS uses and emissions are rapidly restricted.


Assuntos
Ácidos Alcanossulfônicos , Água Potável , Fluorocarbonos , Poluentes Químicos da Água , Exposição Ambiental , Fluorocarbonos/análise , Solo , Poluentes Químicos da Água/análise
4.
Environ Sci Technol ; 56(1): 228-238, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34907779

RESUMO

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+.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Partículas e Gotas Aerossolizadas , Atmosfera , Monitoramento Ambiental , Fluorocarbonos/análise , Poluentes Químicos da Água/análise
5.
Environ Sci Technol ; 56(6): 3471-3479, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35213128

RESUMO

The emission of per- and polyfluoroalkyl substances (PFAS) from functional textiles was investigated via an outdoor weathering experiment in Sydney, Australia. Polyamide (PA) textile fabrics treated with different water-repellent, side-chain fluorinated polymers (SFPs) were exposed on a rooftop to multiple natural stressors, including direct sunlight, precipitation, wind, and heat for 6-months. After weathering, additional stress was applied to the fabrics through abrasion and washing. Textile characterization using a multiplatform analytical approach revealed loss of both PFAS-containing textile fragments (e.g., microfibers) as well as formation and loss of low molecular weight PFAS, both of which occurred throughout weathering. These changes were accompanied by a loss of color and water repellency of the textile. The potential formation of perfluoroalkyl acids (PFAAs) from mobile residuals was quantified by oxidative conversion of extracts from unweathered textiles. Each SFP-textile finish emitted a distinct PFAA pattern following weathering, and in some cases the concentrations exceeded regulatory limits for textiles. In addition to transformation of residual low molecular weight PFAA-precursors, release of polymeric PFAS from degradation and loss of textile fibers/particles contributed to overall PFAS emissions during weathering.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Polímeros de Fluorcarboneto , Fluorocarbonos/análise , Polímeros , Têxteis , Água , Poluentes Químicos da Água/análise
6.
Environ Sci Technol ; 56(10): 6232-6242, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34608797

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are a class of substances for which there are widespread concerns about their extreme persistence in combination with toxic effects. It has been argued that PFAS should only be employed in those uses that are necessary for health or safety or are critical for the functioning of society and where no alternatives are available ("essential-use concept"). Implementing the essential-use concept requires a sufficient understanding of the current uses of PFAS and of the availability, suitability, and hazardous properties of alternatives. To illustrate the information requirements under the essential-use concept, we investigate seven different PFAS uses, three in consumer products and four industrial applications. We investigate how much information is available on the types and functions of PFAS in these uses, how much information is available on alternatives, their performance and hazardous properties and, finally, whether this information is sufficient as a basis for deciding on the essentiality of a PFAS use. The results show (i) the uses of PFAS are highly diverse and information on alternatives is often limited or lacking; (ii) PFAS in consumer products often are relatively easy to replace; (iii) PFAS uses in industrial processes can be highly complex and a thorough evaluation of the technical function of each PFAS and of the suitability of alternatives is needed; (iv) more coordination among PFAS manufacturers, manufacturers of alternatives to PFAS, users of these materials, government authorities, and other stakeholders is needed to make the process of phasing out PFAS more transparent and coherent.


Assuntos
Fluorocarbonos
7.
Environ Sci Technol ; 55(14): 9489-9497, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32859129

RESUMO

Perfluoroalkyl acids (PFAAs) are persistent organic substances that have been widely detected in the global oceans. Previous laboratory experiments have demonstrated effective enrichment of PFAAs in nascent sea spray aerosols (SSA), suggesting that SSA are an important source of PFAAs to the atmosphere. In the present study, the effects of the water concentration of PFAAs on their size-resolved enrichment in SSA were examined using a sea spray simulation chamber. Aerosolization of the target compounds in almost all sizes of SSA revealed a strong linear relationship with their water concentrations (p < 0.05, r2 > 0.9). The enrichment factors (EF) of the target compounds showed no correlation with their concentrations in the chamber water, despite the concentrations varying by a factor of 500 (∼0.3 to ∼150 ng L-1). The particle surface-area-to-volume ratio appeared to be a key predictor of the enrichment of perfluoroalkyl carboxylic acids (PFCAs) with ≥7 perfluorinated carbons and perfluoroalkanesulfonic acids (PFSAs) with ≥6 perfluorinated carbons in supermicron particles (p < 0.05, r2 > 0.8), but not in submicron particles. The different enrichment behaviors of PFAAs in submicron and supermicron particles might be a result of the different production mechanisms of film droplets and jet droplets. The results suggest that the variability in seawater concentrations of PFAAs has little influence on EFs and that modeling studies designed to quantify the source of PFAAs via SSA emissions do not need to consider this factor.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Aerossóis , Monitoramento Ambiental , Fluorocarbonos/análise , Água , Poluentes Químicos da Água/análise
8.
Environ Sci Technol ; 55(3): 1779-1789, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33449633

RESUMO

The influence of soil properties on PFOS sorption are not fully understood, particularly for variable charge soils. PFOS batch sorption isotherms were conducted for 114 temperate and tropical soils from Australia and Fiji, that were well-characterized for their soil properties, including total organic carbon (TOC), anion exchange capacity, and surface charge. In most soils, PFOS sorption isotherms were nonlinear. PFOS sorption distribution coefficients (Kd) ranged from 5 to 229 mL/g (median: 28 mL/g), with 63% of the Fijian soils and 35% of the Australian soils showing Kd values that exceeded the observed median Kd. Multiple linear regression showed that TOC, amorphous aluminum and iron oxides contents, anion exchange capacity, pH, and silt content, jointly explained about 53% of the variance in PFOS Kd in soils. Variable charge soils with net positive surface charges, and moderate to elevated TOC content, generally displayed enhanced PFOS sorption than in temperate or tropical soils with TOC as the only sorbent phase, especially at acidic pH ranges. For the first time, two artificial neural networks were developed to predict the measured PFOS Kd (R2 = 0.80) in the soils. Overall, both TOC and surface charge characteristics of soils are important for describing PFOS sorption.


Assuntos
Poluentes do Solo , Solo , Adsorção , Austrália , Redes Neurais de Computação , Poluentes do Solo/análise
9.
Environ Sci Technol ; 55(19): 12755-12765, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34519210

RESUMO

Despite decades of research on per- and polyfluoroalkyl substances (PFAS), fundamental obstacles remain to addressing worldwide contamination by these chemicals and their associated impacts on environmental quality and health. Here, we propose six urgent questions relevant to science, technology, and policy that must be tackled to address the "PFAS problem": (1) What are the global production volumes of PFAS, and where are PFAS used? (2) Where are the unknown PFAS hotspots in the environment? (3) How can we make measuring PFAS globally accessible? (4) How can we safely manage PFAS-containing waste? (5) How do we understand and describe the health effects of PFAS exposure? (6) Who pays the costs of PFAS contamination? The importance of each question and barriers to progress are briefly described, and several potential paths forward are proposed. Given the diversity of PFAS and their uses, the extreme persistence of most PFAS, the striking ongoing lack of fundamental information, and the inequity of the health and environmental impacts from PFAS contamination, there is a need for scientific and regulatory communities to work together, with cooperation from PFAS-related industries, to fill in critical data gaps and protect human health and the environment.


Assuntos
Fluorocarbonos , Humanos
10.
Environ Sci Technol ; 54(10): 6224-6234, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32364377

RESUMO

A framework for characterizing per- and polyfluoroalkyl substances (PFASs) in life cycle impact assessment (LCIA) is proposed. Thousands of PFASs are used worldwide, with special properties imparted by the fluorinated alkyl chain. Our framework makes it possible to characterize a large part of the family of PFASs by introducing transformation fractions that translate emissions of primary emitted PFASs into the highly persistent terminal degradation products: the perfluoroalkyl acids (PFAAs). Using a PFAA-adapted characterization model, human toxicity as well as marine and freshwater aquatic ecotoxicity characterization factors are calculated for three PFAAs, namely perfluorooctanoic acid (PFOA) perfluorohexanoic acid (PFHxA) and perfluorobutanesulfonic acid (PFBS). The model is evaluated to adequately capture long-term fate, where PFAAs are predicted to accumulate in open oceans. The characterization factors of the three PFAAs are ranked among the top 5% for marine ecotoxicity, when compared to 3104 chemicals in the existing USEtox results databases. Uncertainty analysis indicates potential for equally high ranks for human health impacts. Data availability constitutes an important limitation creating uncertainties. Even so, a life cycle assessment (LCA) case study illustrates practical application of our proposed framework, demonstrating that even low emissions of PFASs can have large effects on LCA results.


Assuntos
Fluorocarbonos/análise , Poluentes Químicos da Água/análise
11.
Environ Sci Technol ; 54(20): 12820-12828, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33043667

RESUMO

Fluoropolymers are a group of polymers within the class of per- and polyfluoroalkyl substances (PFAS). The objective of this analysis is to evaluate the evidence regarding the environmental and human health impacts of fluoropolymers throughout their life cycle(s). Production of some fluoropolymers is intimately linked to the use and emissions of legacy and novel PFAS as polymer processing aids. There are serious concerns regarding the toxicity and adverse effects of fluorinated processing aids on humans and the environment. A variety of other PFAS, including monomers and oligomers, are emitted during the production, processing, use, and end-of-life treatment of fluoropolymers. There are further concerns regarding the safe disposal of fluoropolymers and their associated products and articles at the end of their life cycle. While recycling and reuse of fluoropolymers is performed on some industrial waste, there are only limited options for their recycling from consumer articles. The evidence reviewed in this analysis does not find a scientific rationale for concluding that fluoropolymers are of low concern for environmental and human health. Given fluoropolymers' extreme persistence; emissions associated with their production, use, and disposal; and a high likelihood for human exposure to PFAS, their production and uses should be curtailed except in cases of essential uses.


Assuntos
Fluorocarbonos , Saúde Ambiental , Fluorocarbonos/análise , Humanos , Polietileno
12.
13.
Environ Sci Technol ; 53(24): 14329-14338, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31697071

RESUMO

The quantity and composition of fibers released from functional textiles during accelerated washing were investigated using the GyroWash method. Two fabrics [polyamide (PA) and polyester/cotton (PES/CO)] were selected and coated with perfluorohexane-based side-chain fluorinated polymers. Fibers released during washing ranged from ∼10 to 500 µ with a similar distribution for the two textile types. The PA-based fabric released considerably more fibers >20 µm in length compared to the PES/CO-based fabric (>1000/GyroWash for PA vs ∼200/GyroWash fibers for PES/CO). After one GyroWash (2-15 domestic washes), fibers that contained approximately 240 and 1300 µg total fluorine per square meter (µg F/m2) were released from the PA and PES/CO fabrics, respectively. Current understanding of the fate of microplastic fibers suggests that a large fraction of these fibers reach the environment either in effluent wastewater or sewage sludge applied to land. In the environment, the fluorinated side chains will be slowly cleaved from the backbone of the side-chain fluorinated polymers coated on the fibers and then transformed into short-chain perfluoroalkyl acids. On the European scale, emissions of up to ∼0.7 t of fluorotelomer alcohol (6:2 FTOH) per year were estimated for outdoor rain jackets treated with fluorotelomer-based side-chain fluorinated polymers.


Assuntos
Plásticos , Polímeros , Polímeros de Fluorcarboneto , Microplásticos , Têxteis
14.
Environ Sci Technol ; 51(5): 2508-2518, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28224793

RESUMO

More than 3000 per- and polyfluoroalkyl substances (PFASs) are, or have been, on the global market, yet most research and regulation continues to focus on a limited selection of rather well-known long-chain PFASs, particularly perfluorooctanesulfonate (PFOS), perfluorooctanoic acid (PFOA) and their precursors. Continuing to overlook the vast majority of other PFASs is a major concern for society. We provide recommendations for how to proceed with research and cooperation to tackle the vast number of PFASs on the market and in the environment.


Assuntos
Meio Ambiente , Fluorocarbonos , Humanos
15.
Environ Sci Technol ; 51(8): 4482-4493, 2017 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-28323424

RESUMO

Here a new global emission inventory of C4-C10 perfluoroalkanesulfonic acids (PFSAs) from the life cycle of perfluorooctanesulfonyl fluoride (POSF)-based products in 1958-2030 is presented. In particular, we substantially improve and expand the previous frameworks by incorporating missing pieces (e.g., emissions to soil through land treatment, overlooked precursors) and updating parameters (e.g., emission factors, degradation half-lives). In 1958-2015, total direct and indirect emissions of perfluorooctanesulfonic acid (PFOS) are estimated as 1228-4930 tonnes, and emissions of PFOS precursors are estimated as 1230-8738 tonnes and approximately 670 tonnes for x-perfluorooctanesulfonamides/sulfonamido ethanols (xFOSA/Es) and POSF, respectively. Most of these emissions occurred between 1958 and 2002, followed by a substantial decrease. This confirms the positive effect of the ongoing transition to phase out POSF-based products, although this transition may still require substantial time and cause substantial additional releases of PFOS (8-153 tonnes) and xFOSA/Es (4-698 tonnes) in 2016 to 2030. The modeled environmental concentrations obtained by coupling the emission inventory and a global multimedia mass-balance model generally agree well with reported field measurements, suggesting that the inventory captures the actual emissions of PFOS and xFOSA/Es for the time being despite remaining uncertainties. Our analysis of the key uncertainties and open questions of and beyond the inventory shows that, among others, degradation of side-chain fluorinated polymers in the environment and landfills can be a long-term, (potentially) substantial source of PFOS.


Assuntos
Fluorocarbonos , Modelos Teóricos , Meio Ambiente , Monitoramento Ambiental , Solo
17.
Environ Res ; 158: 269-276, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28662452

RESUMO

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.


Assuntos
Bebidas/análise , Exposição Ambiental , Poluentes Ambientais/análise , Fluorocarbonos/análise , Contaminação de Alimentos/análise , Adulto , Cromatografia Líquida , Dieta/estatística & dados numéricos , Monitoramento Ambiental , Feminino , Humanos , Pessoa de Meia-Idade , Noruega , Avaliação Nutricional , Espectrometria de Massas em Tandem
18.
Environ Sci Technol ; 50(13): 7037-46, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-27304840

RESUMO

The contribution of direct (i.e., uptake of perfluorooctanoic acid (PFOA) itself) and indirect (i.e., uptake of 8:2 fluorotelomer alcohol (FTOH) and metabolism to PFOA) exposure to PFOA serum concentrations was investigated using a dynamic one-compartment pharmacokinetic (PK) model. The PK model was applied to six occupationally exposed ski waxers for whom direct and indirect exposures via inhalation were characterized using multiple measurements with personal air sampling devices. The model was able to predict the diverging individual temporal trends of PFOA in serum with correlation coefficients of 0.82-0.94. For the four technicians with high initial concentrations of PFOA in serum (250-1050 ng/mL), the ongoing occupational exposure (both direct and indirect) was of minor importance and net depuration of PFOA was observed throughout the ski season. An estimated average intrinsic elimination half-life of 2.4 years (1.8-3.1 years accounting for variation between technicians and model uncertainty) was derived for these technicians. The remaining two technicians, who had much lower initial serum concentrations (10-17 ng/mL), were strongly influenced by exposure during the ski season with indirect exposure contributing to 45% of PFOA serum concentrations. On the basis of these model simulations, an average metabolism yield of 0.003 (molar concentration basis; uncertainty range of 0.0006-0.01) was derived for transformation of 8:2 FTOH to PFOA. An uncertainty analysis was performed, and it was determined that the input parameters quantifying the intake of PFOA were mainly responsible for the uncertainty of the metabolism yield and the initial concentration of PFOA in serum was mainly contributing to the uncertainty of estimated serum half-lives.


Assuntos
Caprilatos , Fluorocarbonos , Administração por Inalação , Álcoois , Meia-Vida , Humanos , Modelos Biológicos , Exposição Ocupacional
19.
Environ Sci Technol ; 50(21): 11584-11592, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27689437

RESUMO

An extensive sampling campaign was undertaken to study the levels, isomer profiles and riverine mass discharges of perfluoroalkyl acids (PFAAs) and fluorinated alternatives in 19 Chinese rivers. The levels and homologue profiles of Σ10PFAAs varied considerably among the 19 rivers (mean 106; median 16.3, range 8.9-1240 ng/L), indicating the influence of specific point sources. Highly branched isomer profiles of perfluorooctanoic acid (18-25% br-PFOA) in rivers with elevated concentrations (96-352 ng/L) indicate that releases during production of PFOA by electrochemical fluorination and/or its use in fluoropolymer manufacture were the dominant sources to these rivers. The fluorinated alternatives 6:2 fluorotelomer sulfonate (detection frequency 21%, < 0.1-3.1 ng/L) and chlorinated polyfluoroalkyl ether sulfonate F-53B (51%, < 0.56-78.5 ng/L) were also found in some rivers. The total Chinese riverine mass discharges of PFOA (mean 80.9; range 16.8-168 t/y) (including monitoring data from this and other studies) were in good agreement with theoretical PFOA emission estimates (17.3-203 t/y) whereas riverine mass discharges of PFOS (mean 3.6; range 1.9-5.6 t/y) could only account for a minor fraction of theoretically estimated PFOS releases (70 t/y). This study provides empirical evidence that emissions from Chinese point sources likely dominate the global emissions of several legacy PFASs (notably PFOA) and fluorinated alternatives (e.g., F-53B).


Assuntos
Monitoramento Ambiental , Rios , Isomerismo , Poluentes Químicos da Água
20.
Environ Sci Technol ; 50(2): 653-9, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26653085

RESUMO

Despite international phase-out initiatives, production and use of perfluorooctanesulfonate (PFOS) and related substances continues in some countries. In Brazil, the PFOS-precursor N-ethyl perfluorooctane sulfonamide (EtFOSA) is used in Sulfluramid, a pesticide for controlling leaf-cutting ants. New data on production, environmental fate, and occurrence of Brazilian Sulfluramid are reported herein. From 2003 to 2013, Brazilian Sulfluramid manufacturing increased from 30 to 60 tonnes yr(-1) EtFOSA. During this time <1.3 tonnes yr(-1) were imported, while exports increased from ∼0.3 to 2 tonnes yr(-1). From 2004 to 2015, most EtFOSA was exported to Argentina (7.2 tonnes), Colombia (2.07 tonnes), Costa Rica (1.13 tonnes), Equador (2.16 tonnes), and Venezuela (2.4 tonnes). Within Brazil, sales occurred primarily in the states of Minas Gerais, São Paulo, Mato Grosso do Sul, Espírito Santo, and Bahia. Model simulations predict EtFOSA will partition to soils, while transformation products perfluorooctane sulfonamide (FOSA) and PFOS are sufficiently mobile to leach into surface waters. In support of these predictions, up to 3400 pg L(-1) of FOSA and up to 1100 pg L(-1) of PFOS were measured in Brazilian surface water, while EtFOSA was not detected. The high FOSA/PFOS ratio observed here (up to 14:1) is unprecedented in the scientific literature to our knowledge. Depending on the extent of conversion of EtFOSA, cumulative Brazilian Sulfluramid production and import from 2004 to 2015 may contribute between 167 and 487 tonnes of PFOS/FOSA to the environment. These levels are clearly nontrivial and of concern since production is continuing unabated.


Assuntos
Ácidos Alcanossulfônicos/análise , Fluorocarbonos/análise , Sulfonamidas/análise , Poluentes Químicos da Água/análise , Brasil , Monitoramento Ambiental , Fluorocarbonos/economia , Modelos Teóricos , Sulfonamidas/economia , Poluentes Químicos da Água/economia
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