It has become imperative globally that we build a more sustainable society. Part of the drive towards attaining this includes finding an environmentally friendly solution to materials we use including materials from automobile vehicles. This research is focused on finding a sustainable solution to end-of-life tyres through material recycling into useful products; in this case absorption mats for oil decontamination from tyre rubber granulate.The research consisted of two parts. Firstly, theoretical reviews which involved an extensive literature review of oil decontamination practice and methods of doing it. Review of tyre rubber granulate properties and consultations with experts/agencies involved in oil decontamination operations in Sweden where mostly physical methods such as use of absorbents on land and booms on water. The second component of the research is an experimental part which involved laboratory test of the absorption properties of tyre rubber granulate at University College of Borås (HB) in which granules of sizes 0.50, 1.00 and 2.00 mm were tested on different oil samples; gasoline, diesel and motor oils. Environmental properties tests were also conducted at the Swedish Technical Research Institute (SP) where metal and organic contents of the granules and its leachate were tested.Results from the study showed that tyre rubber granules have the ability to absorb different types of oil. It was found that factors such as exposure time, granulate size, temperature and type of oil have effect on the absorption capacity of granulate. Highest absorption (2.518 g/g) was experienced with the least viscous oil; gasoline. Absorption was found to increase with an increase in temperature and decrease in granulate size with the smallest granulate size (0.50 mm) having the highest absorption at 30oC. It was equally observed that the presence of water does not have significant effect on oil absorption by granulate. The results also showed that tyre rubber granules are quick absorbents; absorption rate was highest within 5 minutes.Environmental properties test on granulate indicated the presence of organics (PAHs, phthalates, phenols) and metals (Pb, Zn, Cr, Cd) in granulate and its leachate. PAHs content of the granules and its leachate exceeded the Swedish guideline. Metal content of the granules and its leachate were below the guideline value with the exception for zinc (Zn) which content in granules exceeded guideline value. It should be noted however that the test conditions are too extreme to be experienced under normal condition of use of granulate for oil decontamination.It is concluded that tyre rubber granulate can be developed into absorption mats for oil decontamination due to its good oils absorption properties and benefits to the society in solving two key environmental problems; oil spill and tyre waste problems. Equally the use of tyre granules for this application will not pose human health and/or environmental risk if used adequately. / Uppsatsnivå: D

Photolysis utilises short wavelength ultraviolet radiation to excite and cleave the carbon-chlorine bond of PCBs, yielding less chlorinated PCBs and ultimately biphenyl which can serve as energy and carbon source of various bacteria. Thus integration of photolysis and biodegradation can be a feasible remediation for PCB contamination. / Polychlorinated biphenyls (PCBs) are ubiquitous environmental pollutants once used as industrial fluids (in hydraulic systems, gas turbines), dielectric fluids (capacitors, transformers), plasticizer (adhesives, textiles, sealants, copy paper), and heat exchangers due to their inertness as well as thermal and electrical insularity. However, they are found to be neurotoxic, immunosuppressive, hepatotoxic, and the USEPA classified PCBs as probable human carcinogens. Although the production of PCBs was banned by the US Congress in 1976, they persist in the environment because of their resistance. Upon entering the marine environment, PCBs will associate with particulates and ultimately with sediment due to their hydrophobic nature and thus sediment become a sink for PCBs. This exerts a threat to marine organisms and human who consume seafood. / The major sink of PCBs in the environment is marine sediment, and the presence of sediment particles as well as other sorbed chemicals may inhibit both photolysis and biodegradation. This study extracts PCBs from sediment and further purify them by various cleanups to prevent the effect of these materials on the efficiency of treatment. / Using 2,4,4'-trichlorobiphenyl (PCB 28), 2,2',5,5'-tetrachlorobiphenyl (PCB 52), 2,2',4,5,5'-pentachlorobiphenyl (PCB 101), 2,2',4,4',5,5'-hexachlorobiphenyl (PCB 153) and 2,2',3,4,4',5,5'-heptachlorobiphenyl (PCB 180) as model compounds, optimal UV intensity, reaction time, as well as reaction solvent were found to be dependent on the congeners used. While PCB 28 was highly reactive and PCB 101, PCB 153 and PCB 180 were comparatively easy to remove, PCB 52 showed high resistance towards photolysis. The photolysis of PCB mixture containing these five congeners with each of them in 1 mg/L was also being optimised. After optimisation, the reaction intermediates and products were identified by gas chromatography coupling mass spectrometry (GC-MS). Less chlorinated congeners and biphenyl were found, indicating stepwise dechlorination of PCB is the major pathway. (Abstract shortened by UMI.) / by Wong Kin Hang. / "August 2005." / Adviser: P. K. Wong. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0159. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 111-140). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Um híbrido inorgânico-orgânico formado por nanozeólita L (nZeol-L) funcionalizada em sua superfície com ftalocianina de silício (SiPC) foi investigado visando uma potencial aplicação para descontaminação de água, via geração de oxigênio singleto (1O2), que por sua vez é citotóxico para sistemas biológicos. Ftalocianinas são corantes orgânicos que possuem comprovada eficiência na geração de oxigênio singleto. No entanto, estes corantes possuem tendência para formar agregados, o que torna ineficiente a formação de 1O2. nZeol-L constitui-se como um material apropriado para suportar SiPC covalentemente em sua superfície com o objetivo de prevenir o processo de agregação, mantendo assim as propriedades fotofísicas dos monômeros do corante. Neste estudo, um híbrido foi preparado visando a fotoinativação da bactéria E. coli (facilmente encontrada em água contaminada) através da luz solar natural. A superfície da nanozeólita L foi funcionalizada com o fotossensitizador (SiPC) e com moléculas de 3-aminopropiltrietoxisilano (APTES) para criar cargas positivas na superfície do material, tornando o híbrido capaz de interagir eletrostaticamente com a superfície negativa das bactérias. Testes de viabilidade celular foram realizados com dois tipos de células: BALB/c 3T3 clone A31 e células de E. coli suspensos em uma solução de PBS (pH 7,4) com a presença do híbrido (nZeol-SiPC/APTES). Foi verificada uma alta eficiência de nZeol-SiPC/APTES em induzir a morte de ambas as células em grande quantidade e dentro de um curto período de tempo. Estes resultados indicam que o nanomaterial (nZeol-SiPC/APTES) possui uma potencial aplicação para a descontaminação de água, quando ativado pela luz do sol. / An inorganic-organic hybrid based on nanozeolite L (nZeol-L) surface-functionalized with silicon phthalocyanine (SiPC) has been investigated aiming its future use in water decontamination by singlet oxygen generation, which is cytotoxic for biological systems. Phthalocyanines are dyes with great efficacy in singlet oxygen generation. However, these dyes have tendency to form aggregates, and hence, the formation of this reactive species of molecular oxygen turns to be inefficient. nZeol-L is an appropriate material to covalently support SiPC on its surface to avoid the aggregation process, thereby maintaining the photophysical properties of the monomer. In this study, a hybrid was prepared aiming the photoinactivation of E. coli bacteria (which is easily found in contaminated water) by natural sunlight. The nanozeolite L surface was functionalized with the photosensitizer (SiPC) and then with 3-aminopropyltriethoxysilane (APTES) molecules to create a positive charge on the material surface, enabling the hybrid to interact with the negative charge to the E. coli bacteria. Cell viability tests were performed with two types of cells: BALB/c 3T3 clone A31 and E. coli cells suspended in PBS solution (pH 7.4) in the presence of the hybrid (here called nZeol-SiPC/APTES). It was verified that nZeol-SiPC/APTES gives rise to the death of the both cells in a large quantity and within a short time interval. These results indicate that the nanomaterial (nZeol-SiPC/APTES) has potential application for water decontamination when activated by sunlight.

A madeira é considerada um compósito natural de extrema complexidade, constituído basicamente por celulose, lignina, hemicelulose (polioses) e extrativos. Sua composição favorece ataques biológicos de diferentes espécies. Neste contexto, inúmeras técnicas vêm sendo estudadas e aplicadas para desinfestar e descontaminar obras de arte e bens culturais móveis elaborados em madeira e que sofreram ataques por fungos, bactérias ou insetos. A irradiação com raios gama, emitidos por isótopos instáveis como o cobalto-60, também vem sendo estudada como uma alternativa para esta finalidade. Este processo tem-se mostrado eficiente para eliminar infestação por insetos e microorganismos em objetos de madeira. Além disso, é rápido e não exige quarentena porque não gera resíduos tóxicos. Neste trabalho, objetivou-se avaliar os efeitos da radiação gama sobre algumas características das espécies de madeira Cedro Rosa e Imbuia. Para tanto, considerou-se que, tal como os demais métodos usualmente empregados na eliminação de microorganismos e insetos que atacam madeiras, o processamento por radiação não impede a reinfestação ou a recontaminação do objeto irradiado. Assim, foram aplicadas doses de radiação gama relativamente altas, até 100 kGy, de modo a investigar os efeitos da radiação, mesmo que as peças de madeira sejam submetidas repetidas vezes ao processo de irradiação, já que a dose absorvida é sempre cumulativa. Estudou-se a influência da radiação gama em propriedades físicas densidade aparente e retratibilidade, em propriedades mecânicas compressão paralela às fibras, flexão no módulo de elasticidade, dureza e cisalhamento e em propriedades térmicas estabilidade térmica das madeiras consideradas. Os resultados demonstraram que a radiação gama, na faixa de dose estudada, não promove alterações nas propriedades das espécies de madeiras investigadas. / Wood is considered a natural composite of extreme complexity, basically composed by cellulose, lignin, hemicelulose (polyosis) and extractives. Its composition favors biological attacks from different species. In this context, several techniques have been studied and applied for disinfecting and decontaminating wood-made works of art and cultural heritage, which have been damaged by fungi, bacteria and insects. Gamma radiation emitted by unstable isotopes, such as 60- cobalt, has also been studied as an alternative to the conventional wood preservatives. So, gamma rays treatment has been shown to be efficient to the removal of infestations by insects and microorganisms in wood-made artifacts, to be fast and not to require quarantine because it does not generate toxic waste. Similar to other techniques, this process does not prevent the irradiated material of re-infestation or recontamination. In this context, the effects of relatively high disinfestation gamma radiation doses (up to 100 kGy) on Cedro Rosa and Imbuia, two typical Brazilian wood species, are accompanied by the changes on the following attributes: apparent density, retracting, parallel compression to fibers, bending in the modulus of elasticity, hardness, shear and thermal stability. Results have shown that gamma radiation, in the studied dose range, does not promote alterations on properties of investigated wood species. In case of a re-infestation, these observations indicate that the wood species can be submitted to repeatedly irradiation processes without causing damage to their structure up to the studied dose range, in despite of radiation effects be always cumulative.

O descarte de embalagens vazias dos agrotóxicos sem fiscalização e controle pode gerar problemas ambientais, afetando a saúde do homem, dos animais e da vida silvestre. Entre os inseticidas comerciais, o clorpirifós tem uma importância significativa por ser amplamente utilizado e persistente no ambiente. O ataque do radical hidroxila, OH é o processo mais eficiente de oxidação química de compostos orgânicos. A degradação de clorpirifós induzida por radiação gama foi estudada em amostras de água e em embalagens de polietileno. Embalagens de polietileno de alta densidade coextrudada em camadas sobrepostas, COEX, contaminadas com clorpirifós foram irradiadas com radiação gama em fonte de Co-60 do tipo \"Gammacell\" e do tipo \"irradiador de grande porte\". As análises de clorpirifós e solventes, assim como dos subprodutos formados foram realizadas por cromatografia a gás associada à espectrometria de massa. A radiação ionizante se mostrou uma técnica eficiente na degradação do inseticida clorpirifós nestas embalagens. / The discharge of empty plastic packaging of pesticides can be an environmental concern causing problems to human health, animals and plants if done without inspection and monitoring. Among the commercial pesticides, chlorpyrifos has significant importance because of its wide distribution and extensive use and persistence. The hydroxil OH atack is the most efficient process of chemical oxidation. The radiation-induced degradation of chlorpyfifos in liquid samples and in polyethylene pack was studied by gamma-radiolysis. Packaging of high density polyethylene tree layer coextruded, named COEX, and water samples contaminated with chlorpyrifos, were irradiated using both, a multipurpose Co-60 gamma irradiator and a gamma source with 5,000 Ci total activity, Gammacell type. The chemical analysis of the chlorpirifos and by-products were made using a gas chromatography associated to the mass spectrometry. Gamma radiation was efficient for removing chlorpyrifós from the plastic packaging in all studied cases.

Le démantèlement des réacteurs UNGG produit un grand volume de matériaux métalliques contaminés. Parmi ceux-ci, les alliages à base de magnésium, connus comme métaux hautement réactifs, présentent un risque élevé de corrosion et peuvent générer de l'hydrogène gazeux qui peut causer de graves dommages pendant le stockage. Afin de réduire le volume des effluents radioactifs générés et de déclasser les déchets nucléaires, la sonochimie peut être mise en œuvre comme technologie efficace pour la décontamination des surfaces métalliques. La sonochimie traite des effets des ondes ultrasonores sur les réactions chimiques en solution. Les effets observés en sonochimie proviennent du phénomène de cavitation acoustique, qui est la nucléation, la croissance et l'effondrement implosif rapide de microbulles remplies de gaz et de vapeur. Des espèces et des radicaux excités peuvent être générés dans le plasma formé, qui émet de la lumière (sonoluminescence). Lorsque l’effondrement des bulles a lieu à proximité d'une surface solide, il produit des ondes de choc violentes et des microjets dirigés vers la surface. Ces effets physiques contribuent fortement au nettoyage par ultrasons, à la dépassivation de surfaces et à la décontamination.Cette étude se concentre sur : 1) les comportements de cavitation près d'une surface solide ; 2) la structuration ultrasonore des surfaces étendues de magnésium ; 3) la décontamination par ultrasons de surfaces métalliques radioactives. L'activité sonochimique est évaluée en mesurant les rendements en H2O2, la distribution de sonochimiluminescence et les spectres de sonoluminescence. Les effets de la structuration et de la décontamination des surfaces sont suivis au moyen de MEB, EDS, FTIR, Raman, DRX, analyse du comportement de mouillage, spectrométrie de masse et ICP-AES.Ce travail a mis en évidence le fort impact de la fréquence ultrasonore sur l'activité sonochimique, sa distribution spatiale et sur les effets générés sur les échantillons de magnésium. Une répartition spatiale homogène de l'activité sonochimique est observée aux fréquences ≥ 100 kHz. L'effondrement asymétrique des bulles est plus susceptible de se produire près de la surface solide aux ultrasons à haute fréquence. La formation d’une structure allongée semblable à une balle de golf est observée à des fréquences comprises entre 100 et 362 kHz. De telles architectures résultent de la dissolution contrôlée par ultrasons de la surface Mg. Il est probable que la nucléation hétérogène assurée par la création de défauts par les ultrasons et la libération de gaz H2 soient à l'origine de la formation des cratères. La décontamination des surfaces radioactives de Mg et d’alliages de Mg ont d'abord démontré un nettoyage rapide par les ultrasons suivi d’un lent processus de recontamination due à l'adsorption de brucite formée sur les surfaces de Mg ou de ses alliages. / The dismantling of UNGG reactors produces large volumes of contaminated metallic materials. Among these, magnesium-based alloys which are known as highly reactive metals, have a high risk of corrosion and can generate hydrogen gas that can cause serious damages during storage. In order to reduce the volume of generated radioactive effluents and downgrade nuclear wastes, sonochemistry can be applied as an efficient technology for metallic surface decontamination. Sonochemistry deals with the effects of ultrasound waves on chemical reactions in solution. The effects observed in sonochemistry originate from the acoustic cavitation phenomenon, which is the nucleation, growth and rapid implosive collapse of gas and vapor filled microbubbles. Excited species and radicals can be generated in the formed plasma and light (sonoluminescence) is emitted. When the bubble collapse takes place in the vicinity of a solid surface, it produces violent shock waves and microjets directed towards the surface. These physical effects strongly contribute in ultrasonic cleaning, surface depassivation and decontamination.This study focuses on: 1) the cavitation behaviors near a solid surface; 2) the ultrasonic structuration of extended magnesium surfaces; 3) the ultrasonic decontamination of radioactive metal surfaces. The sonochemical activity is evaluated by measuring H2O2 yields, sonochemiluminescence distribution and sonoluminescence spectra. Surface structuration and decontamination effects are followed by means of SEM, EDS, FTIR, Raman, XRD, wetting behavior analysis, mass spectrometry and ICP-AES.The investigations reveal a strong ultrasonic frequency dependency of the cavitation activity and distribution and of the effects generated on the Mg samples. A homogeneous spatial repartition of sonochemical activity is observed at frequencies ≥ 100 kHz. Asymmetrical bubble collapse is found more likely to happen near the solid surface at high frequency ultrasound. A golf-ball like extended structure is observed at frequencies between 100 and 362 kHz. It is shown that such architectures result from the ultrasonically controlled dissolution of the Mg surface. Heterogeneous nucleation provided by the creation of defects by ultrasound and the release of H2 gas are supposed to be at the origin of the crater formation. Decontamination of radioactive surfaces of Mg and Mg alloys demonstrate rapid ultrasonic cleaning followed by a slow recontamination process which is due to the adsorption of brucite formed on the surfaces of Mg or its alloys.

Clostridium difficile is a common and potentially fatal cause of antibiotic-associated diarrhoea and pseudomembranous colitis worldwide. It has been isolated from patients and their surroundings, in healthcare facilities and from the community. C. difficile is able to survive for many months on inanimate surfaces in the form of spores. PCR ribotyping is used in the UK to characterise and identify strain diversity. Investigating how the most problematic strains respond to cleaning regimes may influence the control of disease. This work used the University Hospitals of Leicester Trust as a case study for this purpose of understanding the epidemiology of this pathogen within healthcare facilities. Five individual agar media were compared based on their abilities to recover and resuscitate damaged ribotype 027 spores, a strain associated with disease outbreaks and increased severity. Controlled laboratory experiments with a sub-lethal dose of a germicide were conducted before C. difficile recovery from hospital wards. An additional two sampling campaigns acquired environmental strains. C. difficile isolation after routine cleaning demonstrated the inefficiency of the current recovery regime as C. difficile spores were recovered using direct contact plates, enrichment broths, and resuscitation media. This study used layering of non-selective agar over selective agar, identifying a potential link in the proportions of media following the use of sponges in environmental sampling. All strains were characterised by ribotyping; ribotype 027 was isolated from all sampling cohorts. A four-month epidemiological study was conducted into the ribotype prevalence and distribution from C. difficile-positive faecal specimens. A second survey investigated these effects with a modification of C. difficile detection from faecal samples. Hydrogen peroxide vapour is currently being explored as a means of decontamination of healthcare-associated infections. Inactivation kinetics of ribotype 027 spores were analysed in response to vapour and liquid exposure of hydrogen peroxide. No reports thus far have explored such kinetics and controlled decontamination with both clinical and non-clinical strains. Evidence strongly suggests spores can be inactivated with its application. Furthermore, this study revealed there appears to be significant differences in susceptibility and inactivation of different C. difficile ribotypes.

No description available.

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No. of bitstreams: 1 ramos_msm_me_bot.pdf: 1201718 bytes, checksum: 3e156114145adaf97a008a17d305b960 (MD5) Previous issue date: 2018-08-28 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / No contexto da prática assistencial hospitalar, percebe-se a despreocupação de se escolher o método de descontaminação, conforme o potencial de risco do material (não-crítico, semicrítico, crítico) em disseminar patógenos e, consequentemente, infecções cruzadas, empregado em cuidados de higiene de pacientes acamados. A contento, indiscriminadamente, bacias de banho têm sido submetidas à desinfecção de baixo nível, com álcool 70% p/v, aplicado por toda extensão por 30 segundos, após limpeza manual com água corrente e detergente neutro seguida de secagem. Contudo, há literatura recomendando para procedimentos de desinfecção intermediários e de baixo nível em superfícies lisas que o tempo de exposição ao álcool etílico ou isopropílico seja ≥ 60 segundos, nas concentrações de 60 a 90% p/v. Objetivo geral. Avaliar a eficácia do álcool 80% p/v, aplicado por 30 e 60 segundos, no processamento manual de bacias de banho inoxidáveis, após limpeza com água corrente e detergente neutro. Método. Estudo experimental randomizado, com delineamento anterior-posterior, unicego, realizado em centro único (Hospital Público do Estado de São Paulo), em unidade de internação, com média de 150 banhos mensais. Com poder de 80% e confiabilidade de 95%, estimou-se amostra mínima de 50 bacias igualmente distribuídas aleatoriamente em dois grupos: 25 no grupo 30s e 25 no grupo 60s, utilizando-se teste de proporções pareado (dois momentos). Testes microbiológicos antes e após às intervenções foram realizados para os dois grupos. O grupo 30s passou pela intervenção após esfregaço do álcool 80% p/v por 30 segundos e no grupo 60s por esfregaço do mesmo desinfetante por 60 segundos, conforme procedimento operacional padrão proposto. Resultados. Verificou-se eficácia relativa do álcool etílico 80% p/v na descontaminação manual no reuso de bacias de banho inoxidáveis, mesmo elevada de 60% para 64%, quando ampliado o tempo de aplicação de 30 para 60 segundos, após submetê-las à limpeza com água corrente e detergente neutro. Apesar de redução considerável de microrganismos hospitalares, após esfregaço de 30s (5,8 vezes), quanto no de 60s (8,3 vezes), a ação do desinfetante não foi suficiente para descontaminar 36% das bacias, elevando-se para 44% quando o tempo de intervenção foi 30s. Observou-se em ambos grupos maior prevalência de sobrevida de bactérias gram-negativas não fermentadoras, com destaque à Pseudomonas aeruginosa que, apesar de não apresentarem resistência múltipla, 14 cepas foram resistentes à carbapenases, sendo 11 ao imepenen e três ao meropenen. Conclusões. Bacias de banho no leito inoxidáveis descontaminadas para reuso com álcool 80% p/v após limpeza com água corrente e detergente neutro apresentam risco de infecção para pacientes, podendo desempenhar papel de fômites, incluindo cepas importantes para a vigilância, como possíveis produtoras de espectro estendido-beta lactamase (ESBL) e Klebsiella pneumoniae (KPC), Enterococcus Resistente à Vancomicina (VRE) e multirresistentes (resistente a um ou mais antimicrobianos de três ou mais classes). Produto. Relatório final de pesquisa enviado à Agência Nacional de Vigilância Sanitária (ANVISA) brasileira e à Comissão de Controle de Infecção Relacionada à Assistência à Saúde (CCIRAS) local, recomendando bacias de banho inoxidáveis reusáveis como materiais semicríticos, demandando desinfecção de alto nível ou substitui-las por banho no leito descartável. ABSTRACT Introduction. In the hospital care practice context, the lack of concern for choosing the decontamination method, according to the risk potential of the material (non-critical, semi critical, critical) in disseminating pathogens and, consequently, cross-infection, used in hygiene of bedridden patients. Indiscriminately, bath bowls have been subjected to low level disinfection with 70% w/v alcohol, applied for 30 seconds at all times, after manual cleaning with running water and neutral detergent followed by drying. However, there is a literature recommending for intermediate and low-level disinfection procedures on smooth surfaces that the time of exposure to ethyl or isopropyl alcohol is ≥60 seconds at concentrations of 60 to 90% w/v. General objective. To evaluate the efficacy of 80% w / v alcohol, applied for 30 and 60 seconds, in the manual processing of stainless bath bowls, after cleaning. General objective. To evaluate the efficacy of 80% w/v alcohol, applied for 30 and 60 seconds, in the manual processing of stainless bath bowls, after cleaning with running water and neutral detergent. Method. A randomized experimental study, with an anterior-posterior design, single-blind, performed in a single center (Public Hospital of the State of São Paulo), in an inpatient unit, with an average of 150 monthly baths. With 80% power and 95% reliability, a minimum sample of 50 basins was randomly distributed in two groups: 25 in the 30s group and 25 in the 60s group, using a paired proportions test (two moments). Microbiological tests before and after the interventions were performed for both groups. The 30s group underwent the intervention after 80% w/v alcohol smear for 30 seconds and in the 60s group by smearing the same disinfectant for 60 seconds, according to the proposed standard operating procedure. Results. Relative efficacy of 80% w/v ethyl alcohol in manual decontamination in the reuse of stainless bath basins, even from 60% to 64%, was verified when the application time was extended from 30 to 60 seconds, after subjecting them to cleaning with running water and neutral detergent. Despite a considerable reduction of hospital microorganisms, after 30s (5.8 times) and 60s (8.3 times) smear, the action of the disinfectant was not sufficient to decontaminate 36% of the basins, rising to 44% when the intervention time was 30s. A higher prevalence of non-fermenting gram-negative bacteria was observed in both groups, especially Pseudomonas aeruginosa, which, despite not having multiple resistance, 14 strains were resistant to carbapenases, 11 being imepenen and 3 being meropenen. Conclusions. 80% w / v alcohol reuse baths after cleaning with running water and neutral detergent present a risk of infection for patients, and may play a role of fomites, including strains important for surveillance, as possible producers of extended spectrum (ESBL) and Klebsiella pneumoniae (KPC), Vancomycin Resistant Enterococcus (VRE) and multiresistant (resistant to one or more antimicrobials of three or more classes). Product. Final research report sent to the Brazilian National Health Surveillance Agency (ANVISA) and the local Health Care-Related Infection Control Commission (CCIRAS), recommending reusable stainless bath basins as semi-critical materials, requiring high level disinfection or replacing them, by bathing them in the disposable bed. / Introduction. In the hospital care practice context, the lack of concern for choosing the decontamination method, according to the risk potential of the material (non-critical, semi critical, critical) in disseminating pathogens and, consequently, cross-infection, used in hygiene of bedridden patients. Indiscriminately, bath bowls have been subjected to low level disinfection with 70% w/v alcohol, applied for 30 seconds at all times, after manual cleaning with running water and neutral detergent followed by drying. However, there is a literature recommending for intermediate and low-level disinfection procedures on smooth surfaces that the time of exposure to ethyl or isopropyl alcohol is ≥60 seconds at concentrations of 60 to 90% w/v. General objective. To evaluate the efficacy of 80% w / v alcohol, applied for 30 and 60 seconds, in the manual processing of stainless bath bowls, after cleaning. General objective. To evaluate the efficacy of 80% w/v alcohol, applied for 30 and 60 seconds, in the manual processing of stainless bath bowls, after cleaning with running water and neutral detergent. Method. A randomized experimental study, with an anterior-posterior design, single-blind, performed in a single center (Public Hospital of the State of São Paulo), in an inpatient unit, with an average of 150 monthly baths. With 80% power and 95% reliability, a minimum sample of 50 basins was randomly distributed in two groups: 25 in the 30s group and 25 in the 60s group, using a paired proportions test (two moments). Microbiological tests before and after the interventions were performed for both groups. The 30s group underwent the intervention after 80% w/v alcohol smear for 30 seconds and in the 60s group by smearing the same disinfectant for 60 seconds, according to the proposed standard operating procedure. Results. Relative efficacy of 80% w/v ethyl alcohol in manual decontamination in the reuse of stainless bath basins, even from 60% to 64%, was verified when the application time was extended from 30 to 60 seconds, after subjecting them to cleaning with running water and neutral detergent. Despite a considerable reduction of hospital microorganisms, after 30s (5.8 times) and 60s (8.3 times) smear, the action of the disinfectant was not sufficient to decontaminate 36% of the basins, rising to 44% when the intervention time was 30s. A higher prevalence of non-fermenting gram-negative bacteria was observed in both groups, especially Pseudomonas aeruginosa, which, despite not having multiple resistance, 14 strains were resistant to carbapenases, 11 being imepenen and 3 being meropenen. Conclusions. 80% w / v alcohol reuse baths after cleaning with running water and neutral detergent present a risk of infection for patients, and may play a role of fomites, including strains important for surveillance, as possible producers of extended spectrum (ESBL) and Klebsiella pneumoniae (KPC), Vancomycin Resistant Enterococcus (VRE) and multiresistant (resistant to one or more antimicrobials of three or more classes). Product. Final research report sent to the Brazilian National Health Surveillance Agency (ANVISA) and the local Health Care-Related Infection Control Commission (CCIRAS), recommending reusable stainless bath basins as semi-critical materials, requiring high level disinfection or replacing them, by bathing them in the disposable bed. / FAPESP: 2426902

The theoretical part of the thesis is divided in the five main chapters. First chapter generally defines the term ?contamination?, which is closely related to the decontamination. Second chapter is focused on the microbial contamination, defines infectious agents, the mechanisms of its spread and points out microbes most likely to be misused as a biological weapon. Third chapter of the theoretical part addresses the decontamination itself. It defines the decontamination in general aiming for microbial decontamination, i.e. the biological agent surface and environment removal. Two basic groups of decontamination e.g. physical and chemical procedures are mentioned in this chapter. Fourth chapter presents valid standards describing various types of examinations for the desinfecting preparations efficacy evaluation. The last chapter of the theoretical part covers large-scale facilities, defines them and describes experimental facilities at the Department of large-scale testing in the National institute for nuclear, chemical and biological protection in Kamenna. The aim of the thesis is to create own methodology of the disinfactant efficiency testing with emphasis on the real condition simulation. The decontamination was carried out by means of following methods: aerosol generator method, decontamination by evaporation, manual sprayer and engine sprayer respectively. For the analysis we chose these disinfactants: Chirosan? Plus, Incidin OxyDes, Kohrsolin? FF, Korsolex? basic, Persteril? 36 and Sanosil? Super 25 Ag. The disinfectant efficiency was tested in 30, 60 and 120 m3 facilities. The tested B-agents were: Bacillus anthracis, Bacillus atrophaeus, Escherichia coli, Staphylococcus aureus and Streptococcus pneumoniae. For the decontamination efficiency verification we used a modified surface assay, a modified suspension assay and an agarose assay. The following issues were of concern: We found out that, based on the analysis of different techniques of decontamination, the large-scale facility decontamination is feasible. The most effective method of decontamination appears the manual and engine spraying with the latter more convenient for spaces over the 30 m3 in the matter of time. The decontamination by evaporation was inefficient for the large-scale facility decontamination. Experiments revealed that method based on aerosol distribution is convenient for large-scale facility decontamination. However, the nature of decontaminating preparation has to be considered. All disinfactants tested have shown good bactericidal activity. Nevertheless, only Korsolex? basic a Persteril? 36 have shown sufficient sporicidal activity with equal effect. The disadvantage of the preparation Persteril? 36 is its significant corrosive activity, on the other hand is inexpensive. The preparation Korsolex? basic contains anticorrosive compounds, but is more expensive than Persteril? 36. Our results demonstrated that the most convenient method for the decomtamination of facilities up to the 30 m3 is the manual aerosol sprayer. For facilities of larger volume the engine sprayer decontamination is more convenient. From the preparations tested, only Korsolex? basic a Persteril? 36 are, with respect to advantages and disadvantages, usable in the Department of large-scale testing in the National institute for nuclear, chemical and biological protection in Kamenna.