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Per- and polyfluoroalkyl substances (PFASs) are a class of synthetic organic chemicals of global concern. A group of 36 scientists and regulators from 18 countries held a hybrid workshop in 2022 in Zürich, Switzerland. The workshop, a sequel to a previous Zürich workshop held in 2017, deliberated on progress in the last five years and discussed further needs for cooperative scientific research and regulatory action on PFASs. This review reflects discussion and insights gained during and after this workshop and summarizes key signs of progress in science and policy, ongoing critical issues to be addressed, and possible ways forward. Some key take home messages include: 1) understanding of human health effects continues to develop dramatically, 2) regulatory guidelines continue to drop, 3) better understanding of emissions and contamination levels is needed in more parts of the world, 4) analytical methods, while improving, still only cover around 50 PFASs, and 5) discussions of how to group PFASs for regulation (including subgroupings) have gathered momentum with several jurisdictions proposing restricting a large proportion of PFAS uses. It was concluded that more multi-group exchanges are needed in the future and that there should be a greater diversity of participants at future workshops.

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In 2015, > 460,000 L of aqueous film-forming foam (AFFF) and fire suppressors containing per- and polyfluoroalkyl substances (PFAS) were used to combat a fire at a petrochemical fuel storage terminal in the Port of Santos (Brazil). Sediments from seven sites were sampled repeatedly from 2 weeks to 1 year after the fire (n = 30). Æ©15PFAS concentrations ranged from 115 to 15,931 pg g-1 dry weight (dw). Perfluorooctane sulfonic acid (PFOS) was the most frequently detected compound with concentrations ranging from 363 to 4517 (average = 1603) pg g-1dw to <47.1 to 642 (average = 401) pg g-1 dw, followed by perfluorohexanoic acid (PFHxA) (from 38.8 to 219 (average = 162) pg g-1 dw after 15 days and from <20.8 to 161 (average = 101) pg g-1 dw one year later). Together, the hydrodynamics and fire events documented in the region were important features explaining the spread of PFAS.

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Southern Hemisphere Megaptera novaeangliae undertake the longest migration, which reflect their exposure to lipophilic contaminants. To assess these changes, persistent organic pollutants were analyzed in blubber samples of humpback whales from three regions: the Antarctic Peninsula (n = 46), the Strait of Magellan, Chile (n = 22), and the Brazilian coast (n = 38). The similarity in PCB and HCB levels between individuals from feeding grounds and breeding grounds suggests contamination during feeding. The whales around the Antarctic Peninsula exhibited a predominance of tetrachlorobiphenyl PCBs. Whales feeding in the Strait of Magellan showed a slight prevalence of 5Cl biphenyls, likely due to their consumption of subantarctic krill species as well as small fishes potentially contaminated by industrial activities in Chile. The dominance of 5-6Cl congeners in whales in Brazil, may be attributed to the extreme physiological changes during fasting when whales utilize blubber reserves and metabolize lighter congeners, or transfer them to their calves.

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The dispersion of perfluoroalkyl substances (PFAS) in surface and deep-water profiles (down to 5845 m deep) was evaluated through the Western Tropical Atlantic Ocean (TAO) between 15°N and 23°S. The sum concentrations for eight quantifiable PFAS (∑8PFAS) in surface waters ranged from 11 to 69 pg/L, which is lower than previously reported in the same area as well as in higher latitudes. Perfluoroalkyl carboxylic acids (PFCAs) were the predominant PFASs present in the Western TAO. The 16 surface samples showed variable PFAS distributions, with the predominance of perfluorooctanoic acid (PFOA) along the transect (67%; 11 ± 8 pg/L) and detection of perfluoroalkyl sulfonic acids (PFSAs) only in the Southern TAO. Perfluoroheptanoic acid (PFHpA) was often detected in the vertical profiles. PFAS distribution patterns (i.e., profiles and concentrations) varied with depth throughout the TAO latitudinal sectors (North, Equator, South Atlantic, and in the Brazilian coastal zone). Vertical profiles in coastal samples displayed decreasing PFAS concentrations with increasing depth, whereas offshore samples displayed higher PFAS detection frequencies in the intermediate water masses. Together with the surface currents and coastal upwelling, the origin of the water masses was an important factor in explaining PFAS concentrations and profiles in the TAO.

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The biomagnification of per- and polyfluoroalkyl substances (PFASs) was investigated in a tropical mangrove food web from an estuary in Bahia, Brazil. Samples of 44 organisms (21 taxa), along with biofilm, leaves, sediment and suspended particulate matter were analyzed. Sum (∑) PFAS concentrations in biota samples were dominated by perfluorooctane sulfonate (PFOS, 93% detection frequency in tissues; 0.05 to 1.97 ng g-1 ww whole-body (wb)), followed by perfluorotridecanoate (PFTrDA, 57%; 0.01 to 0.28 ng g-1 ww wb). PFOS precursors such as perfluorooctane sulfonamide (FOSA, 54%; 0.01 to 0.32 ng g-1 ww wb) and N-ethyl perfluorooctane sulfonamide (EtFOSA; 30%; 0.01 to 0.21 ng g-1 ww wb) were also detected. PFAS accumulation profiles revealed different routes of exposure among bivalve, crustacean and fish groups. Statistics for left-censored data were used in order to minimize bias on trophic magnification factors (TMFs) calculations. TMFs >1 were observed for PFOS (linear + branched isomers), EtFOSA (linear + branched isomers), and perfluorononanoate (PFNA), and in all cases, dissimilar accumulation patterns were observed among different trophic positions. The apparent biodilution of some long-chain PFCAs through the food chain (TMF < 1) may be due to exposure from multiple PFAS sources. This is the first study investigating bioaccumulation of PFASs in a tropical food web and provides new insight on the behavior of this ubiquitous class of contaminants.

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N-Ethyl perfluorooctane sulfonamide (EtFOSA) is a perfluorooctane sulfonate (PFOS) precursor and the active ingredient in sulfluramid, a pesticide which is used extensively in Brazil for management of leaf cutting ants. Here we investigate the occurrence of EtFOSA, PFOS, and other per- and polyfluoroalkyl substances (PFASs) in soil, eucalyptus leaves, water (ground, riverine, and coastal (estuarine/marine)) and coastal sediment from an agricultural region of Bahia State, Brazil. This area contains a larger number of eucalyptus plantations where sulfluramid is suspected to be applied. Soil, leaves, and coastal water (marine/estuarine) contained ∑PFAS concentrations of up to 5400 pg g-1, 979 pg g-1, and 1020 pg L-1, respectively, with PFAS profiles generally dominated by PFOS and perfluorooctane sulfonamide (FOSA). Coastal sediment contained ∑PFAS concentrations of up to 198 pg g-1, with PFOS, FOSA, and perfluorooctanoic acid (PFOA) being the most frequently observed PFASs. These substances are all potential EtFOSA transformation products, pointing to sulfluramid as a possible source. In riverine water, ∑PFAS concentrations of up to 8930 pg L-1 were observed. PFOS and PFOA were detected in all river water samples. Groundwater also exhibited PFAS contamination (5730 pg L-1 ∑PFASs), likely from sulfluramid use. The observation of other PFASs (e.g. perfluorobutanoic acid) in freshwater suggests that other PFAS sources (in addition to sulfluramid) may be important in this region. Overall, these data support the hypothesis that sulfluramid use contributes to the occurrence of PFASs in the Brazilian environment.

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N-ethyl perfluorooctane sulfonamide (EtFOSA) is the active ingredient of Sulfluramid, a pesticide which is used extensively in South America for control of leaf-cutting ants. Despite being a known precursor to perfluorooctanesulfonate (PFOS), the importance of EtFOSA as a source of environmental PFOS remains unclear. In the present work, uptake, leaching, and biodegradation of EtFOSA and its transformation products were assessed over 81 days in soil-carrot ( Daucus carota ssp sativus) mesocosms for the first time. Experiments performed in the presence of carrot produced PFOS yields of up to 34% using a technical EtFOSA standard and up to 277% using Grão Forte, a commercial Sulfluramid bait formulation containing 0.0024% EtFOSA. Perfluorooctane sulfonamido acetate (FOSAA), perfluorooctane sulfonamide (FOSA), and perfluorooctanoic acid (PFOA) also formed over the course of the experiments, with the latter substance attributed to the presence of perfluorooctanamide impurities. The leachate contained low levels of transformation products and a high FOSA:PFOS ratio, consistent with recent observations in Brazilian surface water. In carrots, the more hydrophilic transformation products (e.g., PFOS) occurred primarily in the leaves, while the more hydrophobic products (e.g., FOSA, FOSAA, and EtFOSA) occurred in the peel and core. Remarkably, isomer-specific analysis revealed that the linear EtFOSA isomer biodegraded significantly faster than branched isomers. These data collectively show that the application of Sulfluramid baits can lead to the occurrence of PFOS in crops and in the surrounding environment, in considerably higher yields than previously thought.

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Temporal patterns, fluxes and inventories of polychlorinated biphenyls (PCBs) were assessed in nine sediment cores collected from selected areas of Admiralty Bay off the Antarctic Peninsula. Concentrations of total PCBs were low, but slightly higher in comparison to low-impacted, remote environments in the world, ranging from below the detection limit to 11.9ngg-1 in dry weight. PCB concentrations and inventories suggest a possible minor influence related to the nearby logistic activities, especially in the sediment core collected close to the Ferraz Station. Despite being the most remote and protected area on the planet, the Antarctic continent is no longer a pristine environment.

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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.

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Este estudo se refere à validação do Atlas de Localização de respostas e da Lista de Qualidade Formal de respostas e conteúdos, FQ, do Rorschach-SC de uma amostra brasileira. Foram selecionados, 46 adultos não-pacientes psiquiátricos, de ambos os sexos, níveis sociais e escolaridade diversos. Os instrumentos utilizados foram o SRQ-20 e o Método de Rorschach. As respostas ao Rorschach foram codificadas segundo as áreas e a lista de qualidade formal norte-americanas e brasileiras. As análises comparativas realizadas por meio da ANOVA não encontraram diferenças entre os dois grupos, no que diz respeito às áreas de localização, W, D, Dd nas áreas brasileiras e norte-americanas, comprovando-se a validade das áreas brasileiras. Não foram também encontradas diferenças quanto à qualidade formal FQo e X+%, nas listas brasileiras e norte-americanas, comprovando-se a validade da lista brasileira para essas duas variáveis. Os resultados indicam validade para o atlas brasileiro.(AU)

This study aimed at validating the Atlas Rorschach-CS Location Areas and Formal Quality List from a Brazilian sample. 46 adults, non-patients psychiatric cases, both genders and different educational levels and social status were selected. The instruments used were the SRQ-20 and the Rorschach method. The Rorschach responses were scoredaccording to the areas and the North-American and Brazilian Lists of formal quality . The comparative analyzes performed by ANOVA did not established differences between the two groups regarding the Location Areas W, D, Dd in both North-American and Brazilian areas, proving the validity of the Brazilian areas. Differences were not found as regarding the Formal Quality FQo and X+% both using the North-American and Brazilian lists, proving the validity of the Brazilian list for these two variables.. The results indicate validity to the Brazilian Atlas.(AU)

Este estudio se refiere a la validación del Atlas de Localización de respuestas y de la Lista de Calidad Formal de respuestas y contenidos, FQ, del Rorschach-SC de una muestra brasileña. Fueron seleccionados, 46 adultos no-pacientes psiquiátricos, de ambos sexos, niveles sociales y de escolaridad diversos. Los instrumentos utilizados fueron el SRQ-20 y el Método de Rorschach. Las respuestas al Rorschach fueron codificadas según las áreas y la lista de calidad formal norteamericanas y brasileñas. Los análisis comparativos realizados, por medio de la ANOVA, no encontraron diferencias entre los dos grupos en lo que respecta a las áreas de localización, W, D, Dd en las áreas brasileñas y norteamericanas, comprobando la validez de las áreas brasileñas. No fueron también encontradas diferencias cuanto a la calidad formal FQo y X+%, en las listas brasileñas y norteamericanas, comprobando la validez de la lista brasileña para esas dos variables. Los resultados indicaron validez para el atlas brasileño.(AU)

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Este estudo se refere à validação do Atlas de Localização de respostas e da Lista de Qualidade Formal de respostas e conteúdos, FQ, do Rorschach-SC de uma amostra brasileira. Foram selecionados, 46 adultos não-pacientes psiquiátricos, de ambos os sexos, níveis sociais e escolaridade diversos. Os instrumentos utilizados foram o SRQ-20 e o Método de Rorschach. As respostas ao Rorschach foram codificadas segundo as áreas e a lista de qualidade formal norte-americanas e brasileiras. As análises comparativas realizadas por meio da ANOVA não encontraram diferenças entre os dois grupos, no que diz respeito às áreas de localização, W, D, Dd nas áreas brasileiras e norte-americanas, comprovando-se a validade das áreas brasileiras. Não foram também encontradas diferenças quanto à qualidade formal FQo e X+%, nas listas brasileiras e norte-americanas, comprovando-se a validade da lista brasileira para essas duas variáveis. Os resultados indicam validade para o atlas brasileiro.

This study aimed at validating the Atlas Rorschach-CS Location Areas and Formal Quality List from a Brazilian sample. 46 adults, non-patients psychiatric cases, both genders and different educational levels and social status were selected. The instruments used were the SRQ-20 and the Rorschach method. The Rorschach responses were scoredaccording to the areas and the North-American and Brazilian Lists of formal quality . The comparative analyzes performed by ANOVA did not established differences between the two groups regarding the Location Areas W, D, Dd in both North-American and Brazilian areas, proving the validity of the Brazilian areas. Differences were not found as regarding the Formal Quality FQo and X+% both using the North-American and Brazilian lists, proving the validity of the Brazilian list for these two variables.. The results indicate validity to the Brazilian Atlas.

Este estudio se refiere a la validación del Atlas de Localización de respuestas y de la Lista de Calidad Formal de respuestas y contenidos, FQ, del Rorschach-SC de una muestra brasileña. Fueron seleccionados, 46 adultos no-pacientes psiquiátricos, de ambos sexos, niveles sociales y de escolaridad diversos. Los instrumentos utilizados fueron el SRQ-20 y el Método de Rorschach. Las respuestas al Rorschach fueron codificadas según las áreas y la lista de calidad formal norteamericanas y brasileñas. Los análisis comparativos realizados, por medio de la ANOVA, no encontraron diferencias entre los dos grupos en lo que respecta a las áreas de localización, W, D, Dd en las áreas brasileñas y norteamericanas, comprobando la validez de las áreas brasileñas. No fueron también encontradas diferencias cuanto a la calidad formal FQo y X+%, en las listas brasileñas y norteamericanas, comprobando la validez de la lista brasileña para esas dos variables. Los resultados indicaron validez para el atlas brasileño.

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Chlorinated pesticides, PCBs and PBDEs were analysed in nine blubber samples of Atlantic spotted dolphins, Stenella frontalis, incidentally captured during fishing operations in southern and southeastern Brazil between 2005 and 2007. The majority of compounds analysed were detected, suggesting widespread contamination over the region. Although the samples came from a location far from main coastal industrial areas, the results revealed an influence from such sources. Therefore, levels of PCBs (774-23659 ng g(-1) lipid wt.) and PBDEs (23-1326 ng g(-1) lipid wt.) detected seem to be related to the movement of individuals throughout near-shore and offshore waters. The sample from a lactating female exhibited a lower level of contamination and a distinct pattern, indicating selective transfer favouring less lipophilic compounds.

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Selected POPs were analyzed in blubber samples of Pontoporia blainvillei from Southern Brazil to appraise temporal trend over a 10 year period (1994-2004). Overall, levels of POPs were relatively low, especially when compared to Northern Hemisphere concentrations. Apart from Mirex and PCBs, which showed stable concentrations, DDTs, HCB, CHLs, Dieldrin levels presented a slight decrease over the studied period. In addition, the increase in the PCBs/DDTs ratio supports the idea that inputs of DDTs are decaying faster than PCBs.

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BACKGROUND: The objective of this double-masked, randomized, multicenter crossover study was to compare the efficacy of 4% articaine HCl with 1:100,000 epinephrine (A100) to 4% articaine HCl with 1:200,000 epinephrine (A200) for providing effective local anesthesia and hemostasis for periodontal surgery. METHODS: Anesthetic efficacy was based on patient self-report and lack of need for reinjection during the surgical procedures. Hemostatic properties of the formulations were compared using ratings of the surgeons' ability to visualize the surgical field and expectation for bleeding. The volume of blood collected during each surgical session also was measured and compared. RESULTS: Forty-two adult subjects (26 males and 16 females, mean age 46.3 +/- 9.7 years) diagnosed with moderate to severe periodontal disease requiring local anesthesia for matched bilateral periodontal surgery were enrolled and completed the study. Subjects reported satisfactory surgical anesthesia following the A100 and A200 formulations; no supplemental local anesthesia was administered. Significant differences between the A100 and A200 treatments were found for the surgeons' ability to visualize the surgical field (rated as clear 83.3% of the time with A100 and 59.5% of the time with A200; P = 0.008), bleeding expectation (rated as equal to or better than expected 85.7% of the time with A100 and 71.4% of the time with A200; P = 0.034), and volume of blood loss (54.9 +/- 36.0 ml for A100 and 70.2 +/- 53.0 ml for A200; P = 0.018). Sixteen patients experienced 27 mild or moderate adverse events; the most common were postoperative pain (nine patients) and swelling (eight patients). Six adverse events may have been related to treatment. The frequency of adverse events did not vary between formulations. CONCLUSIONS: For patients undergoing periodontal surgery, 4% articaine anesthetic formulations containing epinephrine (1:100,000 or 1:200,000) provided excellent surgical pain control. For patients who can tolerate higher amounts of epinephrine, the 4% articaine 1:100,000 epinephrine formulation had the additional therapeutic advantage of providing better visualization of the surgical field and less bleeding.

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OBJECTIVE: The authors conducted two double-blinded, randomized, multicenter clinical trials to determine the efficacy and clinical anesthetic characteristics of 4 percent articaine hydrochloride (HCl) with 1:200,000 epinephrine (A200) as compared with those of 4 percent articaine HCl with 1:100,000 epinephrine (A100) and 4 percent articaine HCl without epinephrine (Aw/o). METHODS: During separate testing sessions, members of the authors' research team used three articaine study formulations to induce either inferior alveolar nerve block anesthesia (Trial 1) or maxillary infiltration anesthesia (Trial 2). In each trial, subjects received, in a randomized sequence, each of the three formulations to determine efficacy (success rate) and anesthetic characteristics (onset time and duration). The authors evaluated pulpal anesthesia via subjects' response to electric pulp testing (EPT). RESULTS: A total of 126 subjects were enrolled in the two studies (63 subjects in each trial). In both mandibular and maxillary trials, the success rates for inducing profound anesthesia (EPT score > 80), the mean onset times and the mean durations of anesthesia were similar for both epinephrine-containing formulations (A200 and A100). In subjects who received the formulation containing no epinephrine (Aw/o), the success rate for profound anesthesia was significantly less. CONCLUSION: These studies demonstrated that the inclusion of epinephrine in 4 percent articaine anesthetic formulations is essential for achieving profound anesthesia. The authors found that the A200 formulation provided a level of pulpal anesthesia comparable with that of the A100 formulation.

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