Per- och polyfluoroalkylämnen (PFAS) är i enkla termer fluorerade kolväten som har använts i ett flertal produkter på grund av deras unika förmåga att vara vatten- och smutsavstötande, värmetåliga samt skiktbildande. PFAS har släppts ut i naturen på flera olika sätt. En stor bov till det är brandskum beståendes av vattenhaltigt filmbildande skum (AFFF), vilket innehåller PFAS. Stora volymer brandskum har släppts ut vid bränder eller brandövningsplatser. PFAS är mycket svårnedbrytbara och bioackumulerande, vilket betyder att de stannar kvar i miljön lång tid framöver. Eftersom de även har bevisats vara hälsofarliga vid små mycket mängder, har många varianter av PFAS blivit bannlysta, samt att rening av PFAS blivit centralt. Det har gjorts väldigt mycket forskning kring hur man renar PFAS från vatten vid dricksvattenproduktion, men inte lika mycket på hur man sanerar PFAS från mark och grundvatten in situ (på plats), främst eftersom det är svårt på grund av PFAS-kemikaliernas egenskaper. Det är en viktig del för att kunna ta bort PFAS ur naturen, då en stor del av den PFAS som blivit utsläppt, vid exempelvis brandövningsplatser, skapat plymer i jord och grundvatten som fortsätter vara spridningspunkter. Syftet med litteraturstudien är att sammanställa och jämföra utvecklande metoder inom området in situ sanering av PFAS för att se vilka metoder som har potential att stoppa spridningen. / Per- and polyfluoroalkyl substances (PFAS) are, in simple terms, fluorinated hydrocarbons that have been used in many products because of their unique ability to be water- and dirt-repellent, heat-resistant, and film forming. PFAS has been released into the environment in several ways. A major culprit is firefighting foam consisting of aqueous film-forming foam (AFFF), which contains PFAS. Large volumes of firefighting foam have been released during fires or firefighting exercises. PFAS are very persistent and bioaccumulative, meaning they stay in the environment for a long time. Since they have also been proven to be harmful to health at very low concentrations, several varieties of PFAS have been banned, and cleaning up PFAS has become a central issue. There has been a lot of research on how to clean PFAS from water during drinking water production, but not as much on how to remediate PFAS from soil and groundwater in situ (on-site), mainly because it is difficult due to the properties of the PFAS chemicals. This is an important part of removing PFAS from the environment since a large part of the PFAS that has been released, for example at firefighting sites, has created plumes in soil and groundwater that continue to be points of spread. The purpose of the literature study is to compile and compare developing methods in the field of in situ remediation of PFAS to see which methods have the potential to stop the spread.

Fluorinated fire fighting foams provide superior performance for extinguishing Class B flammable liquid fires when compared to other types of fire fighting foams. Perfluorocarboxylates and perfluorosulfonates have historically been surfactants used in these foams with a recent shift to fluorotelomer-based foams due to environmental and health concerns surrounding perfluorinated compounds such as PFOA and PFOS. Releases of aqueous film forming foams from training, accidental spills, or fire events where wastewater is not captured have, among other sources, led to detectable concentrations of fluorinated compounds in groundwater, surface water, and drinking water supplies globally. Persistence, toxicity, and bioaccumulation potential of these substances are areas of ongoing research. Biodegradability data for these AFFFs in published studies and manufacturers’ material safety data sheets may be based on a comparison of BOD and COD measures. The present study concludes that COD is an inappropriate measure of organic content for fluorinated compounds due to the carbon-fluorine bond strength, and thus published biodegradability data must be critically evaluated for validity. TOC measured an average of 91% of carbon content for four fluorinated test substances, recommending it for use as an analytical parameter in biodegradability tests when specific compounds’ identities are not required, e.g. in the absence of an LC/MS. Biodegradability of three fluorinated foams (AFFF, AR-AFFF, and FP) purchased from a major U.S. manufacturer measured in the range of 77-96% based on DOC die-away during a 28-day test using activated sludge inoculum. This meets OECD criteria for “ready biodegradability� and NFPA biodegradability recommendations in Standards 18, 18A, and 1150. Defluorination of two foams was measured using ion chromatography and, based on an estimate for total fluorine content developed in part from manufacturer MSDSs, was found to liberate a detectable level of fluorine that was 1 to 2 orders of magnitude less than the estimated value. In this 28-day test, foams underwent significant biodegradation but fluorinated compounds’ biodegradation was likely incomplete.

To evaluate continuous and sporadic nitrification inhibition at the HRSD Nansemond Wastewater Treatment Plant, which has a history of nitrification upsets, continuous sequencing batch reactors (SBRs) were operated to simulate the full-scale plant. Four reactors were operated in this study. One reactor was fed with raw influent (RWI) from the Nansemond Wastewater Treatment Plant (NP). Another was fed with NP primary clarifier influent (PCI), which includes the raw influent, as well as plant recycle streams and truck delivered septage, grease, and chemical toilet waste. The remaining two SBRs were fed with RWI from the VIP Wastewater Treatment Plant, which achieves reliable nitrification year-round. One of these VIP SBRs would remain a control at all times, while the other would be used to evaluate suspected inhibitors to nitrification. The first phase of this project was to determine whether NP was inhibited when compared to VIP, which would be ascertained through a comparison of nitrification performance. The next step was to determine whether the source of inhibition was an industry within the collection system or plant recycles and delivered wastes, which would be ascertained based on comparison of the NR RWI and NP PCI reactor performance. If nitrification performance was comparable between the two SBRs, then it would indicate that the source of inhibition is somewhere within the collection system, whereas if the NP PCI reactor was inhibited when compared to the NP RWI reactor, it would mean that the inhibition is a result of plant recycles or delivered wastes. The next phase would be to determine the specific source by either working back up the collection system or by testing the plant recycles and delivered wastes. After approximately 27 weeks of SBR sampling and monitoring, there was no statistical difference between nitrification rates in reactors A and B, and no signs of nitrification inhibition in either reactor when compared to the VIP control Simulation modeling of reactors A, B, and D (control) was performed with BioWin 3.1 (EnviroSim, Ltd.) as a means for comparison and to ensure reactors were performing as intended. Results suggest that there was some level of continuous inhibition for both NP RWI and PCI reactors, however no sporadic inhibition events were observed. It also appeared that the VIP RWI control reactor experienced some level of continuous nitrification inhibition, although BioWin modeling results indicated that both NP RWI and NP PCI were more inhibitory than VIP RWI. Conclusions drawn from modeling results conflict with those drawn from nitrification rate comparisons. Since solids retention time (SRT) was maintained at exactly 15 days for all reactors, it was assumed that a direct comparison of corrected maximum nitrification rates could be used to compare nitrification performance between SBRs, however the significantly higher influent COD, TKN, and TSS loading to the NP reactors resulted in higher nitrification rates when compared to the VIP RWI control reactors. This was confirmed with BioWin modeling, which also showed consistently higher nitrification rates for NP when compared to VIP RWI, however BioWin also showed that maximum specific growth rates for ammonia-oxidizing bacteria (?maxAOB) in NP RWI and PCI were consistently lower than the ?maxAOB for VIP RWI. This indicates that NP RWI and NP PCI are slightly inhibitory to nitrification, with ?maxAOB values between 0.65 and 0.75 days??, and the fact that both NP RWI and NP PCI are both inhibitory suggests that the source of inhibition is somewhere within the collection system. In a simultaneous study using the reactors fed with raw influent from the VIP Wastewater Treatment Plant, reactor C was spiked with aqueous Film Forming Foam (AFFF) such as that used in methanol feed facility fire suppression systems, while reactor D was left as a control. AFFF was initially added at a concentration of 20 ppm with no effect on either nitrification or denitrification performance. When increased to 40 ppm, the AFFF reactor experienced a complete loss of denitrification, while nitrification rates were not affected when compared with the control reactor. Reactor C took 31 days to fully acclimate to the AFFF feed and fully regain denitrification, and then exhibited no other performance problem throughout this acclimation period. This result was completely unexpected, appears to be repeatable, and is one of very few cases of selective denitrification (and COD uptake) inhibition, as opposed to more commonly observed nitrification inhibition. / Master of Science

Poly- och perfluorerade alkylsubstanser (PFAS) är ett paraplybegrepp för tusentals kemikalier som delar starka kol-fluorbindningar (C-F bindningar). C-F bindningen gör ämnena mycket persistenta och har påvisat skadliga effekter hos både människor och miljö. Sedan 1980-talet har PFAS använts i samband med brandsläckning (Aqeuous Film Forming Foam (AFFF)) (Kemikalieinspektionen, 2013, s. 8), på grund av dess filmbildande förmåga och motståndskraft mot höga temperaturer. Användningen av AFFF anses vara den största källan för spridning av PFAS i svensk miljö över tid (Naturvårdsverket, 2016, s. 48). Människor/miljö som befinner sig i anslutning till flyg- eller brandövningsplatser löper störst risk att exponeras av förhöjda halter av PFAS (Naturvårdsverket, 2016, s. 80).  Syftet med denna studie var att identifiera eventuella spatiala samband mellan individuella släckningsinsatser och förhöjda halter i PFAS i ytvatten, sediment och i fiskvävnad (matriser).  Studien har beaktat samtliga släckningsinsatser med skum mellan åren (2001–2015) i tre Stockholms kommuner, där halter av i PFAS har utvärderats i respektive matris. Med hjälp av miljöövervakningsdata och andra centrala dataunderlag har databearbetning i GIS (geografiska informationssystem) möjliggjorts.   Resultaten av metodiken påvisade inga tydliga korrelationer mellan brandsläckningsinsats/brandövningsplats och förhöjda halter PFOS i respektive matris. Däremot kan ett områdes lokala förutsättningar styra viktiga faktorer som bestämmer huruvida punktutsläppet av PFAS från en brandsläckningsinsats/brandövningsplats blir kvar, eller transporteras bort från platsen. Kunskap över de lokala hydrologiska förhållandena kan vara viktigt för att kunna förutsäga hur PFAS har rört sig i yt- och grundvatten samt mark. Detta kan i sin tur leda till bättre motivering av utredning och insats av specifika områden.

Submitted by Roberta Alves Merguizo Chinellato null (robmerguizo@yahoo.com.br) on 2017-02-13T20:05:29Z No. of bitstreams: 1 DISSERTAÇÃO ROBERTA CORREÇÃO.pdf: 2087375 bytes, checksum: 1e6e52c04ff2049723f222505199bc2f (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-02-15T18:25:56Z (GMT) No. of bitstreams: 1 chinellato_ram_me_svic.pdf: 2087375 bytes, checksum: 1e6e52c04ff2049723f222505199bc2f (MD5) / Made available in DSpace on 2017-02-15T18:25:56Z (GMT). No. of bitstreams: 1 chinellato_ram_me_svic.pdf: 2087375 bytes, checksum: 1e6e52c04ff2049723f222505199bc2f (MD5) Previous issue date: 2017-01-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Com o processo de expansão industrial, as regiões costeiras e estuarinas passaram a perceber a instalação de várias indústrias, devido à proximidade aos mercados consumidores e produtores, além da facilidade de escoamento de sua produção. Essas indústrias consomem uma grande quantidade de água, que é devolvida ao ambiente juntamente com uma série de substâncias tóxicas dissolvidas, incluindo hidrocarbonetos aromáticos, de biodegradabilidade intermediária e tendência à bioacumulação. Regiões estuarinas apresentam maior dificuldade de biorremediação, devido ao fato dos contaminantes ficarem aderidos ao sedimento. Além do descarte costeiro habitual, acidentes tendem a lançar uma quantidade maior e descontrolada de poluentes. A biorremediação é o processo de tratamento que utiliza os microrganismos encontrados tanto no ambiente terrestre como aquáticos contaminados para degradar substâncias toxicamente perigosas transformando-as em substâncias menos ou não tóxicas. As atividades para conter o incêndio no Terminal Químico Aratu S.A. (Ultracargo) lançou grande quantidade de hidrocarbonetos e líquido gerador de filme aquoso (AFFF) no estuário de Santos, modificando o perfil de contaminantes da região. As bactérias heterotróficas de ambientes marinhos apresentam grande potencial de biorremediação. O objetivo do presente trabalho foi avaliar, in vitro, a sucessão de espécies de bactérias heterotróficas em sedimentos do Estuário de Santos, afetados por hidrocarbonetos e AFFF e isolar espécies bacterianas com possível potencial uso em processos de biorremediação. Foram analisadas as densidades de bactérias heterotróficas e identificadas aquelas de maior relevância, por características morfológicas e identificação molecular. Após análise das amostras locais e Microcosmo, destacaram-se as bactérias do gênero Bacillus. A sucessão sugeriu três espécies como potenciais biorremediadoras, sendo elas Bacillus pumilus, Bacillus subtilis e Staphylococcus sp. / With the industrial expansion, coastal and estuarine regions began to perceive installation of several industries, due to the proximity to the consumer markets and producers, besides the ease of transportation of their production. These industries consume a large amount of water, which is returned to the environment with a series of dissolved toxic substances, which includes aromatic hydrocarbons, which are slightly biodegradable and have the tendency to bioaccumulate. Estuarine regions present higher difficulty of bioremediation, since the contaminants are adhered to the sediment. In addition to the usual coastal discard, accidents tend to release a larger and uncontrolled amount of pollutants. Bioremediation is the treatment process that uses microorganisms found in both the terrestrial and aquatic environments to degrade toxic substances by transforming them into less toxic or non-toxic substances. The fire at the Terminal Químico Aratu S.A. (Ultracargo) launched a large amount of hydrocarbons and aqueous film-forming foam (AFFF) in the Santos estuary, modifying the profile of contaminants in the region. The heterotrophic bacteria of marine environments present great bioremediation potential. The objective of the present work was to evaluate in vitro the succession of heterotrophic bacteria species in Santos Estuary sediments affected by hydrocarbons and AFFF and to isolate bacterial species with potential use in bioremediation processes. The densities of heterotrophic bacteria were analyzed and the most relevant ones were identified, by morphological characteristics and molecular identification, where the Bacillus genus deserved attention. The succession suggested three species as potential bioremediators, being Bacillus pumilus, Bacillus subtilis and Staphylococcus sp.

Perfluoroalkyl substances (PFASs) are man-made chemicals. Their unique properties make them beneficial for a wide range of industrial and consumer product applications, such as in aqueous film forming foam (AFFF), durable water repellent clothing, hydraulic oils and food packaging materials. Perfluoroalkyl acids (PFAAs), a class of PFASs, are highly persistent in the environment, and long chain PFAAs are bioaccumulative and toxic. International regulation and voluntary actions by the industry have been implemented and led to a recent reduction of primary emissions of PFAAs to the environment. However, point sources such as AFFF training sites as well as diffuse sources continue to contaminate water bodies, soil and biota. Reducing environmental pollution with PFAAs has therefore become a regulatory priority. Designing successful measures to reduce the PFAA contamination requires an understanding of the sources, transport and fate of PFAAs in the environment. Four scientific publications are included in this PhD thesis, which aimed at increasing the holistic understanding of the fate of PFAAs in aquatic systems. This was achieved by chemical trace analysis combined with mass balance modeling. The following topics were covered: Dispersion and fate of PFAAs from an AFFF-impacted site (Paper I), recirculation of PFAAs in the aquatic environment with focus on waste water treatment plants (WWTPs, Paper II), mass balance of PFAAs in the Baltic Sea (Paper III) and transport and fate of PFAAs in two pristine boreal stream catchments (Paper IV). Results from Paper I showed that AFFF-impacted sites at a former military airfield, which was abandoned for more than 30 years, continue to be point sources of PFAAs to recipients. The sum of PFAAs in the ground water and surface waters ranged from 740 to 51000 ng L-1 and &lt;0.5 to 79 ng L-1, respectively. PFOS in muscle tissue of European perch from a nearby lake ranged from 77 to 370 ng g-1 wet weight, representing among the highest values reported worldwide for fish muscle. In Paper II the relative importance of environmental recirculation of PFAAs versus new releases from the technosphere was investigated for PFAAs in WWTP influents. It was shown that tap water can be an important source of PFAAs to WWTPs in areas with elevated environmental levels. This needs to be taken into account when calculating emissions via WWTP effluents. PFAA mass balances over the WWTPs suggested that PFHxA and PFOA were formed from precursor compounds within the plants. Assembled PFAA mass balances for the Baltic Sea (Paper III) showed that river inflow and atmospheric deposition were the dominant input pathways, while wastewater treatment plant (WWTP) effluents discharging directly into the Baltic Sea made a minor contribution. The inputs of PFAAs were estimated to be higher than the outputs, suggesting a current increase of the PFAA inventory in the Baltic Sea. Also the mass balance study of PFAAs in two remote stream catchments presented in Paper IV revealed that inputs dominated over outputs for both catchments, indicating that a considerable portion of the PFAAs deposited from the atmosphere is retained in soil or in deep ground water and may be released to surface and marine water environments in the future / Perfluoralkilne tvari (PFASs) su umjetne kemikalije. Zbog svojih jedinstvenih svojstava široko su primjenjive u industriji i izradi proizvoda krajnje potrošnje kao što su pjena za gašenje požara (AFFF), vodootporna odjeća, hidraulična ulja i pakiranja za hranu. Perfluoralkilna kiselina (PFAAs) iz skupine perfluoralkilnih tvari iznimno je dugotrajna u okolišu, a dugolančane PFAAs su bioakumulativne i otrovne. Poduzeta međunarodna regulativa i dobrovoljne akcije vodile su nedavno smanjenoj primarnoj emisiji PFAAs u okoliš. Unatoč tome, primarni izvori, kao što su mjesta na kojima se provode treninzi za gašenje požara i difuzni izvori i dalje zagađuju vode, tlo i biotu. Zbog toga, smanjenje onečišćenja okoliša izazvanog PFAAs predstavlja regulatorni prioritet. Stvaranje uspješnih mjera kojima bi se smanjilo onečišćenje izazvano PFAAs zahtjeva razumijevanje izvora, prijenosa i sudbine tih tvari u okolišu. U ovaj doktorat uključena su četiri znanstvena članka kojima je cilj povećati sveukupno razumijevanje sudbine PFAAs u vodenim sustavima. To je postignuto kemijskom analizom elemenata u tragovima u kombinaciji s modeliranjem masene ravnoteže. Obrađene su sljedeće teme: Širenje i sudbina PFAAs na područjima zahvaćenim AFFF (Članak I), ponovna cirkulacija PFAAs u vodenom okolišu s naglaskom na postrojenja za pročišćavanje otpadnih voda (Članak II), masena ravnoteža PFAAs u Baltičkom moru (Članak III) te prijenos i sudbina PFAAs u dva udaljena sjeverna vodena toka (Članak IV).   Rezultati iz Članka I pokazali su da su područja zahvaćena AFFF na bivšem vojnom aerodromu napuštenom prije 30 godina i dalje je glavni izvor PFAA zagadenja okolisa. Zbroj PFAAs u podzemnim i površinskim vodama kreće se u rasponu od 740 do 51000 ng L-1 i &lt;0.5 do 79 ng L-1. PFOS u mišićnom tkivu grgeča iz obližnjeg jezera kreće se od 77 do 370 ng g-1 mokre težine, predstavljajući jednu od najviših vrijednosti u svijetu za riblje mišiće. Članak II istražuje relativnu važnost ponovne cirkulacije PFAAs imajući na umu novu emisiju PFAAs iz tehnosfere u postrojenjima za pročišćavanje otpadnih voda. Cirkulacija/kruženje u okolišu može se pojaviti kada PFAAs iz sustava pitke voda (rijeka, bunara i jezera) odlaze u otpadne vode. Prikazano je kako voda iz slavine može biti važan izvor PFAAs sustavima za pročišćavanje otpadnih voda u područjima s povišenim razinama zaštite okoliša. To se treba uzeti u obzir pri računanju emisije putem strojeva koji se koriste za pročišćenje otpadnih voda. Masena ravnoteža PFAA u postrojenjima za pročišćavanje otpadnih voda upućuje na to da su PFHxA i PFOA stvoreni kao prethodni spojevi unutar postrojenja. Prikupljene masene ravnoteže PFAA za Baltičko more (Članak III) pokazale su da su pritoke rijeka i atmosfersko taloženje dominantni ulazni putovi, dok postrojenja za pročišćenje otpadnih voda pridonose tek u manjoj mjeri. Ulaz PFAAs je procijenjen višim od izlaza, što objašnjava trenutno povećanje sadržaja PFAA u Baltičkom moru. Masena ravnoteža PFAAs u dva udaljena riječna toka predstavljena u Članku IV otkriva da ulaz dominira nad izlazom za oba riječna toka, što upućuje na značajan udio PFAAs koji je iz atmosfere zadržan u tlu ili podzemnim vodama te može biti ispušten u područja površinskih voda i mora. / Perfluorerade alkylsyror (PFAA) är kemikalier som är producerade av människan. Deras unika egenskaper gör att de kan användas i många olika industriella applikationer. PFAAs används i brandsläckningsskum, vattenavvisande kläder, hydrauliska oljor och matförpackningar. PFAAs har visat sig vara persistenta i miljön, och långkedjiga PFAA-homologer har visat sig vara bioackumulerbara samt ha en toxisk verkan. Reglering på internationell nivå tillsammans med initiativ från industrin har lett till minskning av direkta utsläpp. Punktkällor som brandövningsplatser samt andra diffusa källor fortsätter att förorena omgivande vattendrag, jordlager och fauna. Den utbredda föroreningen av PFAAs har därför blivit prioriterad för reglering. För att förstå utsläppen av PFAAs i miljön, hur de transporteras samt deras öde i miljön, är det viktigt att utföra studier som belyser dessa områden.   Denna doktorsavhandling inkluderar fyra vetenskapliga publikationer. Syftet med de underliggande studierna var att öka den holistiska förståelsen av PFAAs rörelse i akvatiska system. Studierna gjordes genom att kombinera kemiska analysmetoder med modellering. Följande  studier genomfördes; Transport och spridning av PFAAs från en brandövningsplats (Paper I), recyklering av PFAAs i den akvatiska miljön med fokus på vattenreningsverk (Paper II), massbalans av PFAAs i Östersjön (Paper III), transport och öde av PFAAs i två pristina vattendrag (Paper IV).   Resultat från (Paper I) visade att brandövningsplatser vid en flygplats som inte har varit i bruk i mer än 30 år, fortfarande är punktkällor av PFAAs till omgivande vattendrag. Summan av PFAAs koncentrationer i grundvattnet och ytvattnet sträckte sig från 740 till 51000 ng L-1 och &lt;0.5 till 79 ng L-1 i respektive vattendrag. Koncentrationen av PFOS i muskelvävnad från  aborre i en av sjöarna var 77 till 370 ng g-1 våtvikt. Dessa värden representerar några av de högsta uppmätta koncentrationerna i världen. I Paper II testades betydelsen av PFAAs från recirkulering i miljön i jämförelse med nya utsläpp från teknosfären. Recirkulering av PFAAs i miljön kan förekomma då PFAAs i inkommande vatten till reningsverk kommer från dricksvatten. Denna studie visar att dricksvatten kan vara en påtaglig källa av PFAAs till vattenreningsverk i områden med förhöjda halter av PFAAs i miljön. Detta måste tas hänsyn till när man beräknar emissioner med utgående vatten från vattenreningsverk. Massbalanser av PFAAs i reningsverken visar att PFHxA och PFOA bildades av prekursorämnen i vattenreningsverken. I Paper III beräknades massbalanserna av PFAAs i Östersjön, beräkningarna visar att floder och atmosfärisk nedebörd var de viktigaste källorna medan utsläppen från vattenreningsverk var markant lägre. Importen av PFAAs estimerades vara högre än exporten, varför vi tror att PFAAs mängden I Östersjön kommer att öka över tid. Vidare gjordes en mass balans av PFAAs i två avlägsna avrinningsområden (Paper IV). Resultaten visar att importen av PFAAs dominerar över exporten från båda avrinningsområdena. Detta indikerar att en stor del av PFAAs som kommer ner via nederbörd kommer att ansamlas i jorden eller i grundvattnet. Dessa PFAAs kan vid senare tillfälle komma att släppas ut till floder som rinner ut i marina vatten. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.</p><p> </p>

Orientador: Ana Julia Fernandes / Resumo: Com o processo de expansão industrial, as regiões costeiras e estuarinas passaram a perceber a instalação de várias indústrias, devido à proximidade aos mercados consumidores e produtores, além da facilidade de escoamento de sua produção. Essas indústrias consomem uma grande quantidade de água, que é devolvida ao ambiente juntamente com uma série de substâncias tóxicas dissolvidas, incluindo hidrocarbonetos aromáticos, de biodegradabilidade intermediária e tendência à bioacumulação. Regiões estuarinas apresentam maior dificuldade de biorremediação, devido ao fato dos contaminantes ficarem aderidos ao sedimento. Além do descarte costeiro habitual, acidentes tendem a lançar uma quantidade maior e descontrolada de poluentes. A biorremediação é o processo de tratamento que utiliza os microrganismos encontrados tanto no ambiente terrestre como aquáticos contaminados para degradar substâncias toxicamente perigosas transformando-as em substâncias menos ou não tóxicas. As atividades para conter o incêndio no Terminal Químico Aratu S.A. (Ultracargo) lançou grande quantidade de hidrocarbonetos e líquido gerador de filme aquoso (AFFF) no estuário de Santos, modificando o perfil de contaminantes da região. As bactérias heterotróficas de ambientes marinhos apresentam grande potencial de biorremediação. O objetivo do presente trabalho foi avaliar, in vitro, a sucessão de espécies de bactérias heterotróficas em sedimentos do Estuário de Santos, afetados por hidrocarbonetos e AFFF e isolar e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: With the industrial expansion, coastal and estuarine regions began to perceive installation of several industries, due to the proximity to the consumer markets and producers, besides the ease of transportation of their production. These industries consume a large amount of water, which is returned to the environment with a series of dissolved toxic substances, which includes aromatic hydrocarbons, which are slightly biodegradable and have the tendency to bioaccumulate. Estuarine regions present higher difficulty of bioremediation, since the contaminants are adhered to the sediment. In addition to the usual coastal discard, accidents tend to release a larger and uncontrolled amount of pollutants. Bioremediation is the treatment process that uses microorganisms found in both the terrestrial and aquatic environments to degrade toxic substances by transforming them into less toxic or non-toxic substances. The fire at the Terminal Químico Aratu S.A. (Ultracargo) launched a large amount of hydrocarbons and aqueous film-forming foam (AFFF) in the Santos estuary, modifying the profile of contaminants in the region. The heterotrophic bacteria of marine environments present great bioremediation potential. The objective of the present work was to evaluate in vitro the succession of heterotrophic bacteria species in Santos Estuary sediments affected by hydrocarbons and AFFF and to isolate bacterial species with potential use in bioremediation processes. The densities of heterotrophic bacteria were analyzed and the most relevant ones were identified, by morphological characteristics and molecular identification, where the Bacillus genus deserved attention. The succession suggested three species as potential bioremediators, being Bacillus pumilus, Bacillus subtilis and Staphylococcus sp... (Complete abstract electronic access below) / Mestre

Aqueous film-forming foam (AFFF) used for fuel firefighting contains polyfluoroalkyl substances (PFAS) that have been identified as environmentally persistent and bioaccumulative resulting in phase out of AFFF. Currently, there are no environmentally friendly foams available that can perform at the same level as AFFF. Fuel transport has been recognized as a potential mechanism behind poor fire extinguishment, but the key features are yet unidentified. To fill these knowledge gaps, identifying the properties and features of surfactants used in firefighting foam that will prevent the transport of liquid fuel through the surfactant solution was imperative. To achieve that, this research was performed exclusively on single surfactants that have applications in firefighting foam. Impact of single surfactants on fuel transport was evaluated. Thermodynamics of the interaction between single surfactants and fuel; and kinetics of fuel transport through single surfactant solutions was observed. It was hypothesized that the liquid fuel transport would influence microstructure in the bulk of the surfactant solution. Experiments were conducted for different single surfactant structures. Various methods were applied to identify the microstructure and interfacial properties of surfactants with and without exposure to liquid fuel. The factor affecting microstructure, identified through this study was further used to evaluate the firefighting performance of single surfactants through ignition test. The thermodynamics of the interaction between fuel and single surfactants helped us to understand the fuel transport mechanism and role of micelle on fuel transport. Surfactant and fuel interaction has been studied below, at, and above the critical micelle concentration of surfactants. The effect of surfactant concentration, convection, and surfactant types were observed on the fuel transport. Moreover, an ignition test was conducted to evaluate the firefighting performance of single surfactants for various fuel types. Overall, the findings from this study will help design a new type of superefficient, environmentally acceptable surfactant for firefighting foam application. / Doctor of Philosophy / Aqueous film-forming foam (AFFF) used for fuel firefighting contains fluorinated compounds which are environmentally persistent and bioaccumulative. Therefore, AFFF has been phased out. There are no environmentally friendly foams available as efficient as current AFFF. Researchers have found that fuel transport through surfactant foam solution is the reason for foam collapse and poor fire extinguishment performance. However, the key parameters affecting fuel transport through foam solution have not been identified. Therefore, new formulations have become challenging, and it is important to identify the parameters affecting fuel transport through the firefighting foams. Surfactants are the key components of firefighting foam. The liquid fuel transport affects the microstructure of the surfactants in the bulk solution. Through this research microstructural and interfacial properties of single surfactants have been studied with and without exposure to liquid fuel. The factors affecting microstructure and firefighting performance of surfactants have been identified. Moreover, the interaction between fuel and single surfactants has been evaluated. The effect of surfactant concentration and fuel type on fuel transport has been observed. Moreover, the effect of convection (at the foam-fuel interface) on fuel transport has been observed. Overall, an understanding of factors affecting fuel transport of firefighting foam is achieved through this research, which can guide new types of efficient, environmentally friendly surfactant design.

Polyimides epitomize one of the most versatile high-performance engineering polymers. Polyimides are inherently mechanically robust, chemically inert, and thermooxidatively stable to 400+ °C depending on their chemical structure, enabling their function in numerous aerospace, electronic, medical, and flame-retardant applications. Polyimides can be highly modular even within synthetic limitations, which promotes and sustains innovative research. One recent interest concerns the innovation of fire suppression foams. Aqueous film-forming foams (AFFFs) are regularly sought when engaging liquid fuel (gasoline, jet fuel) fires. AFFFs utilize perfluorinated compounds (PFCs) like perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), which exhibit toxicity, bioaccumulation, and persistence in the environment resulting in the presence of fluorosurfactant chemicals in environments either through direct or secondary exposure via chemical migration. Recently, the USEPA has even detected PFAS in drinking water at hundreds of military training facilities and civilian airports. While fluorinated compounds provide desirable thermooxidative stability and excellent fire retardancy, the environmental impact imposed by these chemicals strongly encourages research that targets the complete removal of PFCs in conventional formulations. This thesis focuses on the fundamental development of water-soluble sulfonated polyimide (sPI) and poly(amic acid) (sPAA) systems for next-generation polymer-based fire suppression foams. The use of sulfonated monomers and poly(amic acid) salt formation enables tunable structures and water solubilities. The polymers maintain competitive thermal stabilities to conventional polyimides and, when combined with readily available, non-toxic surfactants (SDS), produce stable foams. The MIL-F-24385F performance requirement evaluates foam quality/stability, drainage time, and burnback resistance to access viability and provides comparison to other systems; preliminary testing shows that sPI/sPAA formulations perform well. Solution rheology offers insights into fundamental scaling relationships of specific viscosity vs. concentration in both salt and salt-free solution that are important to future foam development. Additionally, the structural nature of the sPIs/ sPAAs allows for their modification with phosphonium moieties or siloxanes, which are slated to have positive effects on performance. Overall, these sPIs and sPAAs provide a promising platform for the future direction of fire suppression foams. / Master of Science / High-performance polymers are used in the most demanding of engineering applications. Polyimides represent one of the most versatile high-performance polymers. Polyimides are mechanically strong, chemically inert, and resistant to extreme temperatures depending on their chemical structure, allowing their use in numerous aerospace, electronic, medical, and flame-retardant applications. Polyimides are synthetically versatile, which enables the discovery of new uses after decades of research. One new targeted application is fire suppression foams. Aqueous film-forming foams (AFFFs) are the standard when battling liquid fuel (gasoline, jet fuel) fires. AFFFs contain perfluorinated compounds (PFCs), which are toxic and persist in the environment; they migrate easily to affect indirectly exposed ecosystems. Recently, the USEPA has even detected PFAS in drinking water at hundreds of military training facilities and civilian airports. While AFFFs with PFCs are highly effective, replacement materials are needed. This thesis focuses on the fundamental development of water-soluble sulfonated polyimide (sPI) and poly(amic acid) (sPAA) systems for fire suppression foams. The polymers remain thermally stable, and when combined with readily available surfactants (SDS), produce stable foams. Preliminary fire testing shows that sPI/sPAA formulations perform well against military specifications. Solution rheology (study of flow) explores the solution behavior of sPI, which offers insights into fundamental concentration-viscosity relationships that are important to future foam development. Additionally, the structural nature of the sPIs/ sPAAs allows for their modification with phosphonium groups or siloxanes, which changes their characteristics. Overall, these sPIs and sPAAs are initially promising for the future direction of fire suppression foams.

Perfluorerade alkylsyror (PFAS) är en grupp ämnen som de senaste åren har uppmärksammats för dess persistenta, bioackumulerande och toxiska egenskaper för människor och djur. Det är känt att brandövningsplatser där det filmbildande skummet AFFF har använts utgör betydande punktkällor för PFAS. Förutom att förorena marken vid brandövningsplatserna kan PFAS spridas med grundvattnet, vilket har orsakat förorenade dricksvattentäkter på ett flertal platser i Sverige. Hydrogeologiska modeller kan användas för att modellera grundvattnets flöden och medföljande föroreningar. Syftet med examensarbetet är att med en hydrogeologisk modell undersöka föroreningsspridning och transporttider av PFAS-ämnet perfluoroktansulfonat (PFOS) från en brandövningsplats till ytvatten och grundvattentäkter i Bredåkradeltat, väster om Kallinge i Blekinge. Den hydrogeologiska modellen skapades i Visual MODFLOW och transportmodelleringen gjordes med MT3D99 och MODPATH. Modellen kunde reproducera uppmätta grundvattennivåer, med en korrelationskoefficient (R) på 0,98 mellan modellerade och uppmätta nivåer. Med antagandet försumbar adsorption visade modellresultaten att en föroreningsplym med hög PFOS-koncentration (~90.000 ng/l) spreds från brandövningsplatsen till ett våtmarksområde väster om Klintabäcken, och vidare till dalen längs Klintabäcken med lägre koncentrationen (0–4.000 ng/l). Enligt modellen spreds dock inte föroreningen lika långt som uppmätta värden visar. När PFOS väl har nått Klintabäcken bedöms den kunna spridas snabbt med ytvattnet mot grundvattentäkterna, för att sedan infiltrera ned i isälvsmaterialet nära aktiva grundvattentäkter. Transporttiden av PFOS från brandövningsplatsen till Klintabäcken beräknades till sex år för den bäst kalibrerade modellen, vilket betyder att grundvattentäkterna kan ha varit förorenade sedan slutet av 1980-talet eller början av 1990-talet. Beräkningar av masstransport indikerar att runt 3,5 kg PFOS flödar genom Klintabäcken varje år, och att det mesta av den mängden kommer från området vid brandövningsplatsen. Trots förenklingar av Bredåkradeltats komplexa geologi och svårigheter att nå konvergens i modellen bedöms den kunna reproducera hydrogeologiska egenskaper inom deltat, samt föroreningsplymens spridning från brandövningsplatsen till Klintabäcken.