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Health surveillance guides public policies, allows for the monitoring of occupational exposures that may cause health risks, and can prevent work-related diseases. The scoping review protocol herein is designed to map studies on the surveillance of occupational exposure to volatile organic compounds (VOCs) in gas stations and identify the governmental agencies and public health measures in different countries. This review protocol is based on the Joanna Briggs Institute manual and guided by the PRISMA Extension for Scoping Reviews. It includes research articles, theses, dissertations, and official documents on surveillance measures for occupational exposure to VOCs (i.e., benzene, ethylbenzene, toluene, and xylene) in gas stations from different countries. All languages and publication dates will be considered, and a spreadsheet will be used to extract and analyze qualitative and quantitative data. The final version will present the main surveillance measures implemented, responsible entities, results, challenges, limitations, and potential gaps in gas stations.

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This study aimed to evaluate all studies which used the micronucleus assay using oral cells in the attempt to understand whether such technique is efficient in evaluating genotoxicity in gas station attendants. Full manuscripts from 16 studies were carefully selected by the authors. Our results demonstrate that continuous exposure to derivatives of petroleum may lead to genotoxic effects since all studies demonstrated positive findings (16 out of 16) and 11 of them had a strong or moderate final rating. In summary, our results reveal that gas station attendants are occupationally exposed to genotoxic agents and that the micronucleus assay in oral mucosa is indeed an effective method to evaluate genotoxicity in this specific case. Such findings are very important for protecting these professionals who are continuously exposed to chemicals for long periods.

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Sulfur-containing compounds are naturally found in crude oil, and they can be partially removed during the refining process. The wide use of fossil fuels has a significant contribution to sulfur emissions into the atmosphere, and Governments are striving to reduce the amount of the fuels by environmental regulations. The reduction of sulfur levels in diesel and other transportation fuels is beneficial from economic and environmental points, but meeting this standard represents a major operational and economic challenge for the oil and gas industry. Quantitative measurement of the sulfur amount must be taken along the oil refining chains guided by standards of measurement and recommended analytical methods such as various American Society for Testing and Materials methods (ASTM D2622, ASTM D5453, ASTM D7039, and ASTM D7220). Advancement in the refining processes and environmental regulations also require reliable measurements and well-defined criteria for compliance assessment. This work presented a brief review of the ASTM Standards used in the laboratories of the Brazilian oil and gas industry to determine the total sulfur content in fuels. We also presented an approach based on the reproducibility of the measurement methods and the guard band concept to evaluate the conformity statement.

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Two extraction protocols were developed for the determination of mono- and poly-aromatic hydrocarbons in water-soluble fractions from gasoline, diesel, crude, mineral insulating, and lubricant oils. Development of the procedures was based on clean miniaturized strategies, such as headspace extraction and vortex-assisted dispersive liquid micro-extraction, together with quantification by gas chromatography-mass spectrometry. The mono-aromatic hydrocarbons were extracted using the headspace extraction method. The linear range obtained was 10-500 µg L-1, with r2 > 0.99. Based on the parameters of the analytical curves, detection and quantification limits of 2.56-3.20 and 7.76-9.71 µg L-1 were estimated. In addition, the method showed adequate recoveries of 69.4-83.5%, with a satisfactory precision of 4.7-17.1% (n = 5). Micro-extraction was applied for the poly-aromatics and the most favorable variables were sample volume (5.00 mL) in sodium chloride medium (1%, w/v), trichloromethane as extractor solvent (75 µL), acetone as disperser (925 µL) and vortexing for 1 min. Under these conditions, analytical curves of 0.15-4.00 µg L-1 were obtained and limits of determination and quantification were 0.03-0.15 and 0.09-0.46 µg L-1, respectively. Recovery values of 87.6-124.5% and a maximum relative standard deviation of 18.9% (n = 5) verify satisfactory accuracy and precision. This led to the achievement of enrichment factors for poly-aromatic hydrocarbons of 41-89 times. Finally, the methods were employed in samples of water-soluble fractions for the determination of analytes. The values followed the order: gasoline > diesel > crude > lubricant > mineral insulating oil. These results indicate an increase in lighter fractions, followed by poly-aromatics in more refined products.

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Objetivo: Determinar los efectos de la exposición a vapores de gasolina sobre la función pulmonar en vendedores informales. Material y métodos: Estudio descriptivo de corte transversal realizado en expendedores informales de gasolina expuestos a sus vapores en el municipio de Maicao, Colombia. Se registraron datos sociodemográficos, se evaluó la función pulmonar por medio de espirometría, oximetría de pulso y, evaluación de la exposición a biomasa. Resultados: Se evaluaron 74 pacientes. El 87,8% eran de sexo masculino, encontrándose principalmente entre los 18 - 40 años (71,6%). El 21,6% (n=16) de la población reportó tener afecciones respiratorias, el 59,4% obtuvo un VEF1 <80% predicho, el 68,9% un FVC <80% predicho y, el 32,4% un VEF1/FVC <70% predicho. De aquellos que tuvieron espirometría anormal (n=45), el 62,2% reportó tener un tiempo de labor ≥ 5 años. Los síntomas reportados con mayor frecuencia fueron disfonía (14,8%), conjuntivitis (14,8%), epigastralgia (10,8%) y cefalea (9,45%). No se encontraron diferencias estadísticamente significativas entre la alteración de la espirometría y antecedentes, saturación de oxígeno medida y presencia de afección respiratoria. Conclusión: Este estudio encontró que un porcentaje representativo de vendedores informales de gasolina expuestos a vapores de combustibles en la frontera colombo-venezolana, presentaron alteración en la función pulmonar comprobado por espirometría anormal y, algunos reportaron sintomatología y afección respiratoria. Estos, son principalmente hombres, adultos jóvenes, con nivel socioeconómico y educacional bajo y, expuestos a diario de forma prolongada y por varios años, a gases derivados del manejo de combustibles fósiles.

SUMMARY Objective: To determine the effects of fuel vapor exposure on pulmonary function among informal sellers. Methods: Cross-sectional study carried-out among informal fuel sellers in Maicao, Colombia. Sociodemographic data were gathered as well as pulmonary function by spirometry, pulse oximetry and evaluation of biomass exposure. Results: 74 patients were evaluated; 87.8% were males, 71.6% of them had between 18 to 40 years of age; 21.6% (n=16) reported pulmonary diseases; 59.4% had a predicted FEV1 <80%; 68.9% had a predicted FVC <80% and 32.4% had a predicted FEV1/FVC < 70%. Among those who had abnormal spirometry, (n=45) 62.2% reported to had worked ≥5 years. The most common reported symptoms were dysphonia (14.8%), conjunctivitis (14.8), epigastric pain (10.8) and headache (9.45%). No statistically significant differences were found between spirometry alterations and history of p pulmonary diseases, mean oxygen saturations and presence of a respiratory disease. Conclusions: This study demonstrates that a significant proportion of informal fuel sellers exposed to fuel vapors in the Colombian-Venezuelan border had derangement of the pulmonary function measured by spirometry and that some of them reported symptoms and respiratory disease. Young male adults of low socioeconomic and educational levels with prolonged exposure to fuel vapors are mostly affected.

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Gasoline is the most common transportation fuel in Brazil, with up to 1% of benzene. Benzene is a health-damaging organic solvent that is extensively used worldwide, being classified as a human carcinogen by the International Agency for Research on Cancer (Group 1). Many workers at filling stations are exposed to benzene, present in gasoline. The main routes of exposure and absorption of benzene are inhalation, oral, and dermal routes. The penetration and maintenance of benzene and other chemicals on personal protective equipment and clothing of workers who manipulate these solvents may increase their levels of exposure and offer risks to their family members, since contaminated clothing is laundered at their homes, which goes against legislative framework (Annex 2, Regulatory Standard No. 9). This way, the objective of this work was to discuss the importance of periodic changes and cleaning of filling station attendant uniforms performed by employers as preventive measures against the deterioration of the health of workers and their family members. We performed a narrative review; no systematic criteria were used in the search for national and international studies. After critical reading, we observed a lack of consistent data on this theme. Laundering of uniforms worn by filling station attendants should take place outside the domestic environment in order to protect the health of workers and their family members and avoid possible cross-contamination.

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Lead has been widely used since antiquity, but its uses drastically increased during the Industrial Revolution. The global emission of Pb into the environment was mainly due to tetraethyl lead added to gasoline as an antiknock additive. Because of its toxicity and neurological effects, the compound was phased out in the 1980s. Isotopic signatures are widely applied to differentiate sources of Pb; however, this is an expensive and sophisticated analysis compared to elemental analysis. Thus, this study aims to gain insight into leaded gasoline registered in mud depocenters from the southeastern Brazilian coast using multivariate statistical tools on elemental analysis data of trace elements. Seven multiple cores were collected on board the Research Vessel Alpha Crucis. Al, As, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, P, Pb, Sc, Sr, V and Zn were analyzed by acid digestion and quantified by ICP-OES. Levels and enrichment factors of Pb resulted in homogeneous columns, indicating that small variations in concentrations can be attributed to grain size differences, not presenting contaminated levels. From statistical results, the highest contribution on the first component was represented by a lithogenic source with the leaching of continental rocks. Lead content was notable in its high loadings in other components, which suggests atmospheric deposition. An increase in these components in subsurface samples from vertical profiles between 1935 and 1996 could represent a fingerprint of the consumption of leaded gasoline in Brazil between 1923 and 1989. Thus, statistical analysis of elemental data enabled to infer possible sources and pathways of Pb to the environment, without isotopic analysis.

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Workers exposed to fuels and paints may present alterations in several parameters. Thus, we assessed potential biomarkers, with the aim of detecting early changes in gasoline station attendants and painters. Blood samples were collected for the analysis of inflammatory and DNA damage markers, besides biochemical, haematological and oxidative stress parameters. Biochemical and haematological parameters, which are assessed with routine exams, showed few changes. However, these findings could mask the workers' real health status. Besides, markers of oxidative damage were not modified. Levels of inflammatory parameters (cytokines and nitric oxide levels) and the DNA damage marker 8-hydroxydeoxyguanosine were significantly changed in the workers. Our results suggest that inflammatory and DNA damage parameters can be potential biomarkers for the biological monitoring of workers exposed to fuels and paints and may contribute to the development of occupational protection standards.

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INTRODUCTION: Headache attacks may be triggered by several factors, among them odors, especially in migraine patients. OBJECTIVES: The aim of this study wasto determine the association between gasoline odor and headache attacks in patients with migraine or tension-type headache (TTH). SUBJECTS AND METHODS: The study was prospective, cross-sectional, with comparison of groups, using nonrandom sample and convenience. Fifty-two gas station workers diagnosed with migraine or TTH according to ICHD-3 criteria were interviewed on the relationship between gasoline odor and headache. RESULTS: Of the 52 gas station workers with headaches, there were 39 (75%) with migraine without aura and 13 (25%) with TTH. The age ranged from 19 to 50 years, with a mean of 29.5 ± 7.2 years. Osmophobia during headache attacks predominated in workers with migraine (29/39; 74.4%). The onset of headache due to odor exposure occurred in 23/39 (60%) of the workers with migraine and in 2/13 (15.4%) in TTH. These differences were statistically significant (χ2 = 7.4; p = 0.016). Osmophobia in the absence of pain (period between attacks) predominated in workers with migraine (17/39, 43.6%), but with no statistical value. CONCLUSIONS: Gas station workers diagnosed with migraine or TTH may experience osmophobia and headache triggered by the odor of gasoline.

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BACKGROUND AND OBJECTIVE: Gas station attendants are occupationally exposed to benzene, toluene, ethylbenzene and xylene (BTEX) compounds and thus more susceptible to the biological effects of this mixture present in gasoline, especially due to the carcinogenicity of benzene. Furthermore, the harmful effects of BTEX exposure may be potentiated by genetic and epigenetic inactivation of critical genes. The objective was to evaluate such gene-BTEX interactions accessing the promoter methylation status of p14ARF, p16INK4A and GSTP1 in peripheral blood leukocyte samples. MATERIALS AND METHODS: The 59 exposed and 68 unexposed participants from Rio de Janeiro, Brazil, were included. The promoter methylation status was accessed by methylation-specific PCR (MSP) and GSTP1 Ile105Val polymorphism was investigated by PCR-restriction fragment length polymorphism (PCR-RFLP) technique. RESULTS: Both p14ARF and p16INK4A were significantly hypermethylated in exposed subjects compared to unexposed (p = 0.004 and p<0.001, respectively). Additionally, p16INK4A hypermethylation in the exposed group was correlated with chromosomal abnormalities (CAs) (p = 0.018), thus highlighting the influence of the gene-environment interactions on genome instability. Noteworthy, p16INK4A methylation was significantly associated with miscarriage among female attendants (p = 0.047), in which those who reported miscarriage exhibited hypermethylation in at least 2 of the 3 genes analyzed. The GSTP1 heterozygote genotype, which could affect the metabolism of benzene detoxification, was found in both groups but was more frequent in those occupationally exposed. No significant association was observed between GSTP1 genotypes and methylation status. CONCLUSION: Together, these findings indicate that gas station attendants with the aforementioned epigenetic and genetic profiles may be at greater risk of occupational BTEX exposure-induced genome instability, which could require concerted efforts to establish more preventive actions and constant biomonitoring in gas station attendants.

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In this work a simple and practical method for the determination of Pb and Ni in automotive gasoline by solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry was investigated. In the proposed method, disks of filter paper were used to pre-concentrate and store Pb, Ni and other trace elements from automotive gasoline samples. For this, a volume of sample was deposited and dried out on a filter paper disk previously adapted into a polytetrafluoroethylene mold, and then the gasoline-embedded filter paper was either cut into small pieces or pulverised and introduced directly into the graphite furnace for trace element determination. Temperature program, use of chemical modifier, chromatographic effect and volume of sample were investigated. Calibration curves using organic and inorganic standards of the analytes as well as external and internal calibration methods were evaluated. Using optimised conditions, characteristic masses and limits of detection of 6 and 11 pg, and 0.5 and 2.1 µg L-1 were found for Pb and Ni, respectively. The accuracy of the method was evaluated with spike-recovery tests and a certified reference material of wear lubricant oil. The spike-recovery tests were accomplished for 9 samples and the best results were obtained with the pulverised filter paper. A second method that employs a transversely heated filter atomiser was applied as a comparative one. The filter paper was shown to be a simple and inexpensive tool for storage and transportation of gasoline samples, and it allowed the pre-concentration of the analytes, since a larger volume of sample can be dried out on it.

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Contamination caused by leakage at gas stations leads to possible exposure of the general population when in contact with contaminated water and soil. The present study aimed to evaluate the reproductive effects of exposure of adult male rats to gasohol and evaluate the performance of machine learning (ML) algorithms for pattern recognition and classification of the exposure groups. Rats were orally exposed to 0 (control), 16 (EA), 160 (EB), or 800 mg kg-1 bw day-1 of gasohol (EC), for 30 consecutive days. Sperm quality of the groups exposed to two higher doses was reduced in comparison to the control group. The sperm parameters decreased were: daily sperm production, sperm number in the caput/corpus epididymis, progressive motility, mitochondrial activity, and acrosomal membrane integrity. Sperm transit time in the epididymis cauda and sperm isolated head were increased in EB and EC. Sertoli cells number was decreased in these groups, but their support capacity was maintained. ML methods were used to identify patterns between samples of control and exposure groups. The results obtained by ML methods were very promising, obtaining about 90% of accuracy. It was concluded that the exposure of rats to different doses of gasohol impair spermatogenesis and sperm quality, with a recognizable classification pattern of exposure groups at ML.

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The energy reforms implemented in Mexico promote the use of ethanol in gasoline but exclude the country's ozone nonattainment areas oxygenated with methyl-tert-butyl ether (MTBE) in view that further scientific studies are required. To address a potential implementation scenario in areas of ozone high VOC-sensitive regimes, the impact on performance and emissions characteristics between the regular MTBE fuel available and a formulated gasoline containing 10% v/v ethanol having similar Reid vapor pressure (RVP) were compared in a single cylinder spark-ignited engine and a set of tier I vehicles. Included in the assessment were the "criteria" pollutants (THC, CO, and NOx), toxic compounds, and speciated hydrocarbons in order to calculate the ozone-forming potential (OFP). The change in combustion speed of ethanol fuel vs. regular gasoline seems to be small and depends mainly on base gasoline formulation. Vehicle dynamometer testing showed no statistically significant differences in the average THC, CO, and NOx results when comparing both fuels. Statistically significant differences were seen in total speciated hydrocarbons, total carbonyls emitted, the increases in acetaldehyde emissions, and the decreases in OFP with E10. The results show roughly 20% increase in evaporative emissions when E10 is used, but the OFP of the emissions is lower than that of the Metropolitan Area of Mexico City fuel (MAMC). The increase in the oxygen content using ethanol fuel seems to have no deleterious effect on the vintage of vehicles tested. Taking into consideration that the evaporative emissions standard in Mexico is less stringent than that in other countries, the substitution of the actual regular gasoline for ethanol fuels should uphold the least volatile AA class in areas with ozone problems.

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Communities resident in urban areas located near active volcanoes can experience volcanic ash exposures during, and following, an eruption, in addition to sustained exposures to high concentrations of anthropogenic air pollutants (e.g., vehicle exhaust emissions). Inhalation of anthropogenic pollution is known to cause the onset of, or exacerbate, respiratory and cardiovascular diseases. It is further postulated similar exposure to volcanic ash can also affect such disease states. Understanding of the impact of combined exposure of volcanic ash and anthropogenic pollution to human health, however, remains limited. The aim of this study was to assess the biological impact of combined exposure to respirable volcanic ash (from Soufrière Hills volcano (SHV), Montserrat and Chaitén volcano (ChV), Chile; representing different magmatic compositions and eruption styles) and freshly-generated complete exhaust from a gasoline vehicle. A multicellular human lung model (an epithelial cell-layer composed of A549 alveolar type II-like cells complemented with human blood monocyte-derived macrophages and dendritic cells cultured at the air-liquid interface) was exposed to diluted exhaust (1:10) continuously for 6 h, followed by immediate exposure to the ash as a dry powder (0.54 ±â€¯0.19 µg/cm2 and 0.39 ±â€¯0.09 µg/cm2 for SHV and ChV ash, respectively). After an 18 h incubation, cells were exposed again for 6 h to diluted exhaust, and a final 18 h incubation (at 37 °C and 5% CO2). Cell cultures were then assessed for cytotoxic, oxidative stress and (pro-)inflammatory responses. Results indicate that, at all tested (sub-lethal) concentrations, co-exposures with both ash samples induced no significant expression of genes associated with oxidative stress (HMOX1, NQO1) or production of (pro-)inflammatory markers (IL-1ß, IL-8, TNF-α) at the gene and protein levels. In summary, considering the employed experimental conditions, combined exposure of volcanic ash and gasoline vehicle exhaust has a limited short-term biological impact to an advanced lung cell in vitro model.

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ABSTRACT Purpose: to investigate the toxicity effects of major hydrocarbons present in gasoline on the auditory system and the related mechanisms of action. Methods: a literature review between 2005 and 2015 was conducted using LILACS, MEDLINE and SciELO, by combining descriptors and their respective terms in Portuguese, English and Spanish. Results: studies performed in humans and animals with hearing impairment, confirmed by morphological tests in rats, the influence of factors such as dose, duration, species and type of stimulus in hearing loss, and ineffective protection of workers by the threshold levels of exposure in the mixture of the compounds, were chosen. Conclusion: toluene is regarded as an ototoxic compound that damages outer hair cells in the middle region of the cochlea, with evidence of interaction with noise. Ethylbenzene and xylenes can be considered potentially ototoxic based on the results of animal studies. No sufficient data were found on benzene to form a conclusion.

RESUMO Objetivo: realizar levantamento sobre a toxicidade ao sistema auditivo e os respectivos mecanismos de ação provocados pelos principais hidrocarbonetos presentes na gasolina. Métodos: revisão bibliográfica, entre os anos de 2005 a 2015, realizada nas bases LILACS, MEDLINE e SciELO, por meio da combinação de descritores e seus respectivos termos em português, inglês e espanhol. Resultados: foram identificados estudos em animais e humanos com danos auditivos confirmados por exames morfológicos em ratos; influência de fatores como dose, duração, espécie e tipo de estímulo na perda auditiva; e insuficiência de proteção dos trabalhadores pelos níveis limites de exposição na mistura dos compostos. Conclusão: de acordo com os resultados, tolueno é considerado ototóxico, lesando células ciliadas externas em região média da cóclea, com evidências de interação com ruído; etilbenzeno e xilenos podem ser considerados potencialmente ototóxicos, devido a estudos com animais; e sobre o benzeno não foram encontrados dados suficientes para conclusões.

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Studies on fire behavior are extremely important as they contribute in a firefighting situation or even to avoid such hazard. Experimental studies of fire in real scale are unfeasible, implying that reduced-scale experiments must be performed, and results extrapolated to the range of interest. This research aims to experimentally study the fire behavior in tanks of 0.04m, 0.20m, 0.40m, 0.80m and 4.28m diameter, burning regular gasoline or diesel oil S-500. The following parameters were here obtained: burning rates, burning velocities, heat release rates, flame heights, and temperature distributions adjacent to the tank. Such parameters were obtained for each tank diameter with the purpose of correlating the results and understanding the relationship of each parameter for the different geometrical scale of the tanks. Asymptotic results for larger tanks were found as (regular gasoline and diesel oil S-500, respectively): burning rates 0.050kg/(m2s) and 0.031kg/(m2s), burning velocities 4.0mm/min and 2.5mm/min, heat release rates per unit area 2200kW/m2 and 1500kW/m2, normalized averaged flame heights (Hi/D, where Hi is the average flame height, D is the tank diameter) 0.9 and 0.8. Maximum temperatures for gasoline pools were higher than for diesel oil pools, and temperature gradients close to the tanks were also higher for the former fuel. The behavior of the maximum temperature was correlated as a function of the tank diameter, the heat release rate of each fuel and the dimensionless distance from the tank.

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RESUMEN Introducción: Las parasitosis intestinales causadas por geohelmintos son consideradas un problema de salud pública que afectan principalmente a países en va de desarrollo y son proclives a presentarse en población infantil. Los métodos diagnósticos para identificar estas entidades parasitarias son el coprológico directo y las técnicas de concentración. El método establecido por la Organización Mundial de la Salud-OMS para identificar y cuantificar geohelmintiasis es el Kato-Katz; sin embargo, este no permite realizarse en trabajos de campo con periodos de tiempo prolongados, debido a que su análisis debe llevarse a cabo en las primeras 48 horas de toma de la muestra de materia fecal. Objetivo: Implementar el uso del fijador SAF (Acetato de sodio - Ácido acético - Formaldehído) en la técnica de Kato-Katz-OMS y evaluar la estabilidad de las estructuras de las entidades parasitarias, después de un periodo de doce meses de toma muestra y realizar comparación con la técnica de concentración Ritchie-Frick modificada (formol-gasolina), para determinar los valores de sensibilidad-S, especificidad-E, valor predictivo positivo-VPP y negativo-VPN y determinar la prevalencia del parasitismo intestinal y sus posibles variables asociadas en la comunidad infantil en edad preescolar y escolar del municipio de Chaguaní Cundinamarca. Materiales y Métodos: Se analizaron 67 muestras correspondientes a toda la población infantil en edad preescolar y escolar del área urbana del municipio de Chaguaní Cundinamarca, las cuales fueron valoradas por los métodos de Kato-Katz-SAF y concentración de Ritchie-Frick modificada (formol-gasolina) y posterior análisis microscópico. Resultados: La prevalencia de geohelmintiasis fue de 46,3%, la técnica de Kato-Katz-SAF presentó valores de S, E, VPP y VPN del 100% y la técnica de concentración de Ritchie-Frick modificada (formol-gasolina) S 60,8%, E y VPP 100% respectivamente y VPN 62,1%; la prevalencia para protozoos por este método fue de 65,7% hallándose agentes etiológicos patógenos y de carácter zoonótico. Se identificó que las variables onicofagia, consumo de agua sin proceso de cloración o hervido, presencia de vectores mecánicos, convivencia con animales domésticos como caninos, hacinamiento en la vivienda y uso poco frecuente de calzado, son variables de posible asociación estadística con la presencia de entidades parasitarias. Se determinó nivel de parasitemia por geohelmintiasis leve para esta población. Conclusión: El estudio reveló que el uso del reactivo de SAF puede implementarse en trabajos de campo prolongados conservando los estadios infectivos de las entidades geohelmínticas como: Ascaris lumbricoides, Trichuris trichiura y Uncinarias por un periodo de hasta doce meses.

ABSTRACT Introduction: The intestinal parasitic diseases caused by geohelminths are considered a public health problem that primarily affect developing countries and are likely to occur in children. The diagnostic methods to identify these parasitic entities are the direct stool and concentration techniques. The method established by the World Organization of the Health-WHO to identify and quantify geohelmintiasis is the Kato-Katz; however, this does not occur in fieldwork with long periods of time, since analysis should be performed in the first 48 hours of the sampling of fecal matter. Objective: Implement the use of SAF fixative (sodium acetate - acetic acid - formaldehyde) in the technique of Ka-to-Katz-WHO and to assess the stability of the structures of the entities parasitic, after a period of twelve months of taking shows and make comparison with the technique of modified Ritchie-Frick (formol-gasoline) concentration, to determine the values of sensitivity-S, specificity-E, predictive value PPV-positive and negative-VPN and determine the prevalence of intestinal parasitism and its possible variables associated in the infant community preschool and in schools of the municipality of Chaguanín Cundinamarca. Materials and methods: 67 samples corresponding to the entire child population at preschool and school age of the urban area of the municipality of Chaguani in Cundinamarca, which were valued by the methods of Kato-Katz-SAF and concentration of modified Ritchie-Frick (formol-gasoline) and subsequent microscopic analysis. Results: The prevalence of geohelmintiasis was 46.3%, the technique of Kato-Katz-SAF presented values of S, E, VPP, and 100% and VPN technique of concentration of modified Ritchie-Frick (formol-gasoline) 60.8% S, E and VPP 100% respectively and VPN 62.1%; the prevalence for protozoa by this method was 65.7% being etiologic agents pathogenic and zoonotic character. It was identified as variables onicofagia, consumption of water without boiling or chlorination process, the presence of mechanical vectors, coexistence with domestic animals such as dogs, overcrowded housing and less frequent use of footwear, are variables of possible statistical association with the presence of parasitic entities. Level of parasitemia was determined by mild geohelmintiasis for this population. Conclusion: Study revealed that the use of SAF reagent can be deployed in field work extended to conserving the infective stages of entities as geohelminths: Ascaris lumbricoides, Trichuris trichiura and hookworms for a period of up to twelve months.

RESUMO Introdução: As doenças parasitárias intestinais causadas por geohelmintos são consideradas um problema de saúde pública que afeta principalmente os países em desenvolvimento e é provável que ocorram em crianças. Os métodos de diagnóstico para identificar essas entidades parasitas são as fezes diretas e as técnica de concentração. O método estabelecido pela Organização Mundial da Saúde-OMS para identificar e quantificar geohelmintiasis é o Kato-Katz; No entanto, isso não ocorre no trabalho de campo com longos períodos de tempo, uma vez que a análise deve ser realizada nas primeiras 48 horas da amostragem de matéria fecal. Objetivo: Implementar o uso de fixador SAF (acetato de sódio - ácido acético - formaldeído) na técnica de Kato-Katz-OMS e avaliar a estabilidade das estruturas das entidades parasitárias, após um período de doze meses de exibição e exibição comparação com a técnica de concentração modificada de Ritchie-Frick (formol-gasolina), para determinar os valores de sensibilidade-S, especificidade-E, valor preditivo PPV-positivo e VPN negativo e determinar a prevalência de parasitismo intestinal e suas possíveis variáveis associadas na comunidade pré-escolar da comunidade infantil e nas escolas do município de Chaguanín Cundinamarca. Materiais e métodos: 67 amostras correspondentes a toda a população infantil na idade pré-escolar e escolar da área urbana do município de Chaguani em Cundinamarca, que foram avaliadas pelos métodos de Kato-Katz-SAF e concentração de Ritchie-Frick modificado (formol -gasolina) e posterior análise microscópica. Resultados: A prevalência de geohelmintiasis foi de 46,3%, a técnica de Kato-Katz-SAF apresentou valores de S, E, VPP e 100% e VPN de concentração de Ritchie-Frick modificada (formol-gasolina) 60,8% S, E e VPP 100% respectivamente e VPN 62,1%; A prevalência de protozoários por este método foi de 65,7% sendo agentes etiológicos patogênicos e de caráter zoonótico. Identificou-se como variáveis onicofagia, consumo de água sem processo de ebulição ou cloração, presença de vetores mecânicos, coexistência com animais domésticos, como cães, carcaça superlotada e uso menos freqüente de calçados, variáveis de possível associação estatística com a presença de parasitas entidades. O nível de parasitemia foi determinado por geohelmintiasis leve para esta população. Conclusão: O estudo revelou que o uso do reagente SAF pode ser implantado em trabalhos de campo estendidos para conservar os estádios infecciosos das entidades como geohelminas: Ascaris lumbricoides, Trichuris trichiura e ancilostomídeos por um período de até 12 meses.

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This study investigates the effects of several blends of gasoline and anhydrous ethanol on exhaust emission concentrations of carbon monoxide (CO), total hydrocarbons (HCs), and nitrogen oxides (NOx) from a small spark-ignited non-road engine (SSINRE). Tests were carried out for different air/fuel equivalence ratios as measured by lambda (λ). A 196 cm3 single-cylinder four-stroke engine-generator operating at a constant load of 2.0 kW was used; pollutant gas concentrations were measured with an automatic analyzer similar to those typically used in vehicle inspections. The results showed that as the ethanol content of the mixture increased the concentrations of CO, HCs, and NOx reduced by 15, 53, and 34%, respectively, for values of λ < 1 (rich mixture) and by 52, 31, and 16% for values of λ > 1 (lean mixture). Overall, addition of anhydrous ethanol to the gasoline helped to reduce emissions of the pollutant gases investigated, what contributes to photochemical smog reduction and quality of life in urban areas.

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We aimed to verify the changes in the microbial community during bioremediation of gasoline-contaminated soil. Microbial inoculants were produced from successive additions of gasoline to municipal solid waste compost (MSWC) previously fertilized with nitrogen-phosphorous. To obtain Inoculant A, fertilized MSWC was amended with gasoline every 3 days during 18 days. Inoculant B received the same application, but at every 6 days. Inoculant C included MSWC fertilized with NP, but no gasoline. The inoculants were applied to gasoline-contaminated soil at 10, 30, or 50 g/kg. Mineralization of gasoline hydrocarbons in soil was evaluated by respirometric analysis. The viability of the inoculants was evaluated after 103 days of storage under refrigeration or room temperature. The relative proportions of microbial groups in the inoculants and soil were evaluated by FAME. The dose of 50 g/kg of inoculants A and B led to the largest CO2 emission from soil. CO2 emissions in treatments with inoculant C were inversely proportional to the dose of inoculant. Heterotrophic bacterial counts were greater in soil treated with inoculants A and B. The application of inoculants decreased the proportion of actinobacteria and increased of Gram-negative bacteria. Decline in the density of heterotrophic bacteria in inoculants occurred after storage. This reduction was bigger in inoculants stored at room temperature. The application of stored inoculants in gasoline-contaminated soil resulted in a CO2 emission twice bigger than that observed in uninoculated soil. We concluded that MSWC is an effective material for the production of microbial inoculants for the bioremediation of gasoline-contaminated soil.(AU)

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Abstract We aimed to verify the changes in the microbial community during bioremediation of gasoline-contaminated soil. Microbial inoculants were produced from successive additions of gasoline to municipal solid waste compost (MSWC) previously fertilized with nitrogen-phosphorous. To obtain Inoculant A, fertilized MSWC was amended with gasoline every 3 days during 18 days. Inoculant B received the same application, but at every 6 days. Inoculant C included MSWC fertilized with N–P, but no gasoline. The inoculants were applied to gasoline-contaminated soil at 10, 30, or 50 g/kg. Mineralization of gasoline hydrocarbons in soil was evaluated by respirometric analysis. The viability of the inoculants was evaluated after 103 days of storage under refrigeration or room temperature. The relative proportions of microbial groups in the inoculants and soil were evaluated by FAME. The dose of 50 g/kg of inoculants A and B led to the largest CO2 emission from soil. CO2 emissions in treatments with inoculant C were inversely proportional to the dose of inoculant. Heterotrophic bacterial counts were greater in soil treated with inoculants A and B. The application of inoculants decreased the proportion of actinobacteria and increased of Gram-negative bacteria. Decline in the density of heterotrophic bacteria in inoculants occurred after storage. This reduction was bigger in inoculants stored at room temperature. The application of stored inoculants in gasoline-contaminated soil resulted in a CO2 emission twice bigger than that observed in uninoculated soil. We concluded that MSWC is an effective material for the production of microbial inoculants for the bioremediation of gasoline-contaminated soil.

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