Research progress in epigenetic toxicity of diesel exhausts / 环境与职业医学

Diesel exhaust (DE) can enter the organism body and cause multiple organ damage. DE contains particles that can be suspended in the air for a long time. Epigenetic regulation is a post transcriptional regulation change that does not involve DNA sequence changes. Many evidences showed that DE can affect the normal physiological functions of multiple organs and systems through epigenetic changes, thus regulating the occurrence and development of multiple diseases. This paper reviewed the research progress of DNA methylation and non-coding RNA in the biological harmful effects of DE. This will provide a basis for the safety evaluation, health risk assessment, and management of DE.

Análisis de la mezcla de alcoholes en motor diésel

Debido a que el futuro del petróleo es incierto, en la búsqueda de los combustibles alternativos se ha encontrado que el alcohol es un fuerte candidato como combustible; los alcoholes inferiores más representativos son el metanol y el etanol, los cuales han demostrado en general baja miscibilidad, por lo que pueden generar una separación de fases al ser mezclados después de un cierto tiempo. La única manera de emplearlos en un motor diésel es mezclándolos con biodiésel o con surfactantes. Por el contrario, los alcoholes superiores tienen características más adecuadas para ser mezclados o empleados en el motor diésel. Por su parte, los éteres son una buena opción cuando se trate de combustión piloto en que se considere emplear combustibles gaseosos como el biogás o el syngas en motor diésel dual. En esta investigación se exploran las alternativas que existen para mejorar las características del alcohol, por ejemplo, mezclarlo con biodiésel, biogás, agua o nanopartículas, y también se analizan las emisiones que se producen con las mezclas generadas. El objetivo es indagar las diferencias entre los alcoholes inferiores y los alcoholes superiores de cadena larga, así como las mezclas que se pueden generar para mejorar el rendimiento del motor. Los resultados afirman que los alcoholes de cadena larga tienen mejores propiedades físico-químicas que los alcoholes de cadena corta; el butanol es el único combustible que puede ser transportado y almacenado en las mismas redes de tuberías actuales de los productos petroleros existentes. También se cuenta con la opción de usar el alcohol como combustible piloto en un motor diésel dual; esto puede servir para aplicar una enorme variedad de combustibles tanto líquidos como gaseosos, lo cual hace que las opciones en su aplicación se incrementen. Como conclusión, se recomienda explorar nuevas mezclas analizando sus sinergias con varios combustibles alternativos. La posibilidad de realizar el diesterol-BED genera resultados muy alentadores, por lo que se recomienda seguir haciendo análisis sobre esa línea para encontrar la mezcla óptima.

As the future of oil is uncertain and in the search for alternative fuels, it has been found that alcohol is a strong candidate as a fuel. The most representative lower alcohols are methanol and ethanol, which have generally demonstrated low miscibility so that they can generate phase separation when mixed after a certain period of time. The only way to use them in a diesel engine is to mix them with biodiesel or surfactants. By contrast, higher alcohols have more suitable characteristics to be mixed or used in the diesel engine. In the case of ethers they are a good option when it comes to pilot combustion considering using gaseous fuels such as biogas or syngas in dual diesel engine. This research explores the alternatives that exist to improve the characteristics of alcohol as it can be mixed with biodiesel, biogas, water or nanoparticles and also analyzes the emissions that are generated with the mixtures. The aim of this research is to explore the differences between lower alcohols and long chain upper alcohols, as well as the mixtures that can be generated to improve engine performance. The results of this research claim that long-chain alcohols have better physico-chemical properties than short-chain alcohols, butanol being the only fuel that can be transported and stored in the same current pipeline networks of existing oil products. There is also the option to use alcohol as a pilot fuel in a dual diesel engine. The latter can be used to apply a huge variety of both liquid and gaseous fuels, this makes the options in its application increase. As a conclusion of this work, it is recommended to explore new mixtures analyzing their synergies with various alternative fuels. The possibility of performing diesterol-BED generates very encouraging results, therefore it is recommended to continue to perform analyses on that line to find the optimal mixture.

Na busca por combustíveis alternativos porque o futuro do petróleo é incerto, verificou-se que o álcool é um forte candidato como combustível, onde os álcoois inferiores mais representativos são o metanol e o etanol, que, em geral, demonstraram baixa miscibilidade, de modo que podem gerar separação de fase quando misturadas após um determinado período de tempo, a única forma de as utilizar num motor diesel é misturá-las com biodiesel ou tensioactivos, pelo contrário, os álcoois superiores têm características mais adequadas para serem misturados ou utilizados no motor diesel, no caso dos éteres, são uma boa opção quando se trata de combustão piloto, considerando a utilização de combustíveis gasosos, como biogás ou gás de síntese em motores a diesel duplos, esta pesquisa explora as várias alternativas que existem para melhorar as características do álcool, pois pode ser misturado com biodiesel, biogás, água ou nanopartículas e também analisa as emissões que são geradas com as misturas geradas, O objetivo desta pesquisa é explorar as diferenças entre álcoois inferiores e álcoois superiores de cadeia longa, bem como as misturas que podem ser geradas para melhorar o desempenho do motor. Os resultados desta pesquisa afirmam que os álcoois de cadeia longa têm melhores propriedades físico-químicas do que os álcoois de cadeia curta, sendo o butanol o único combustível que pode ser transportado e armazenado nas mesmas redes de gasodutos atuais que os produtos petrolíferos existentes, há também a opção de usar álcool como combustível piloto em um motor diesel duplo, Este último pode ser usado para aplicar uma enorme variedade de combustíveis líquidos e gasosos, o que aumenta as opções em sua aplicação. Como conclusão deste trabalho recomenda-se explorar novas misturas analisando suas sinergias com vários combustíveis alternativos, a possibilidade de realizar diesterol-BED gera resultados muito encorajadores, portanto, recomenda-se continuar a realizar análises nessa linha para encontrar a mistura ideal.

Association of etheno-DNA adduct and DNA methylation level among workers exposed to diesel engine exhaust / 中华预防医学杂志

Objective@#To investigate the association between etheno-DNA adduct and the promoter of DNA methylation levels of cyclin dependent kinase inhibitor 2A (P16), Ras association domain family 1 (RASSF1A) and O-6-methylguanine-DNA methyltransferase (MGMT) in workers with occupational exposure to diesel engine exhaust (DEE).@*Methods@#We recruited 124 diesel engine testing workers as DEE exposure group and 112 water pump operator in the same area as control group in Henan province in 2012 using cluster sampling. The demographic data were obtained by questionnaire survey; urine after work and venous blood samples were collected from each subject. The urinary etheno-DNA adducts were detected using UPLC-MS/MS, including 1,N6-etheno-2'-deoxyadenosine (εdA) and 3,N4-etheno-2'-deoxycytidine(εdC). The DNA methylation levels of P16, RASSF1A, and MGMT were evaluated using bisulfite-pyrosequencing assay. The percentage of methylation was expressed as the 5-methylcytosine (5mC) over the sum of cytosines (%5mC). Spearman correlation and multiple linear regression were applied to analyze the association between etheno-DNA adducts and DNA methylation of P16, RASSF1A, and MGMT.@*Results@#The median (P25-P75) of urinary εdA level was 230.00 (98.04-470.91) pmol/g creatinine in DEE exposure group, and 102.10 (49.95-194.48) creatinine in control group. The level of εdA was higher in DEE exposure group than control group (P<0.001). DNA methylation levels of P16, RASSF1A and MGMT were 2.04±0.41, 2.19 (1.94-2.51), 2.22 (1.94-2.46)%5mC in exposure group, and 2.19±0.40, 2.41 (2.11-2.67), 2.44 (2.15-2.91)%5mC in control group. DNA methylation levels were lower in exposure group (P values were 0.005, 0.002 and 0.001, respectively). Spearman correlation analysis showed that DNA methylation levels of P16, RASSF1A, and MGMT were negative associated with urinary εdA level (r values were -0.155, -0.137, and -0.198, respectively, P<0.05). No significant correlation was observed between the εdC level and any measured DNA methylation levels (P>0.05) . Multiple linear regression confirmed the negative correlation between εdA and DNA methylation levels of P16, RASSF1A, and MGMT in non-smoking group (β (95%CI) was -0.068 (-0.132--0.003), -0.082 (-0.159--0.004) and -0.048 (-0.090--0.007), P values were 0.039, 0.039 and 0.024, respectively). Moreover, εdC was negative associated with DNA methylation level of MGMT in non-smoking group (β (95%CI) was -0.094 (-0.179--0.008), P=0.032).@*Conclusion@#DEE exposure could induce the increased of εdA and decreased of DNA methylation levels of P16, RASSF1A and MGMT.

Estimates of the Number of Workers Exposed to Diesel Engine Exhaust in South Korea from 1993 to 2013

BACKGROUND: The aim of this study was to estimate the number of workers exposed to diesel engine exhaust (DEE) by industry and year in the Republic of Korea. METHOD: The estimates of workers potentially exposed to DEE in the Republic of Korea were calculated by industry on the basis of the carcinogen exposure (CAREX) surveillance system. The data on the labor force employed in DEE exposure industries were obtained from the Census on Establishments conducted by the Korea National Statistical Office from 1993 to 2013. The mean values of prevalence rates adopted by EU15 countries were used as the primary exposure prevalence rates. We also investigated the exposure prevalence rates and exposure characteristics of DEE in 359 workplaces representing 11 industries. RESULTS: The total number of workers exposed to DEE were estimated as 270,014 in 1993 and 417,034 in 2013 (2.2% of the total labor force). As of 2013, the industry categorized as “Land transport” showed the highest number of workers exposed to DEE with 174,359, followed by “Personal and household services” with 70,298, “Construction” with 45,555, “Wholesale and retail trade and restaurants and hotels” with 44,005, and “Sanitation and similar services” with 12,584. These five industries, with more than 10,000 workers exposed to DEE, accounted for 83% of the total DEE-exposed workers. Comparing primary prevalence rates used for preliminary estimation among 49 industries, “Metal ore mining” had the highest rate at 52.6%, followed by “Other mining” with 50.0%, and “Land transport” with 23.6%. CONCLUSION: The DEE prevalence rates we surveyed (1.3–19.8%) were higher than the primary prevalence rates. The most common emission sources of DEE were diesel engine vehicles such as forklifts, trucks, and vans. Our estimated numbers of workers exposed to DEE can be used to identify industries with workers requiring protection from potential exposure to DEE in the Republic of Korea.

Increase of diesel car raises health risk in spite of recent development in engine technology

Diesel exhaust particles (DEP) contain elemental carbon, organic compounds including Polyaromatic hydrocarbons (PAHs), metals, and other trace compounds. Diesel exhaust is complex mixture of thousands of chemicals. Over forty air contaminants are recognized as toxicants, such as carcinogens. Most diesel exhaust particles have aerodynamic diameters falling within a range of 0.1 to 0.25 microm. DEP was classified as a definite human carcinogen (group 1) by the International Agency for Research on Cancer at 2012 based on recently sufficient epidemiological evidence for lung cancer. Significant decreases in DEP and other diesel exhaust constituents will not be evident immediately, and outworn diesel car having longer mileage still threatens health of people in spite of recent remarkable development in diesel engine technology. Policy change in South Korea, such as introduction of diesel taxi, may raise health risk of air pollution in metropolitan area with these limitations of diesel engine. To protect people against DEP in South Korea, progressive strategies are needed, including disallowance of diesel taxi, more strict regulation of diesel engine emission, obligatory diesel particulate filter attachment in outworn diesel car, and close monitoring about health effects of DEP.

Desempenho comparativo de um motor de ciclo diesel utilizando diesel e misturas de biodiesel / Comparative performance of a cycle diesel engine using diesel and biodiesel mixtures

Os atuais elevados preços do barril de petróleo no mercado internacional, a possibilidade de geração de postos de trabalho e renda com a conseqüente fixação do homem no campo, as excelentes e variadas condições climáticas e os tipos de relevo fazem com que o Brasil, com suas extensas áreas agricultáveis, destaque-se no cenário mundial em relação à sua grande potencialidade de geração de combustíveis alternativos. A situação ambiental faz com que o ser humano trabalhe no desenvolvimento de alternativas energéticas, destacando-se aquelas oriundas de fontes renováveis e biodegradáveis de caráter eminentemente sustentável. Assim, objetivou-se com este trabalho avaliar o desempenho de um motor ciclo diesel, funcionando em momentos distintos com diesel mineral e misturas deste com biodiesel nas proporções equivalentes a B2 (98 por cento de diesel mineral e 2 por cento de biodiesel), B5 (95 por cento de diesel mineral e 5 por cento de biodiesel), B20 (80 por cento de diesel mineral e 20 por cento de biodiesel) e B100 (100 por cento de biodiesel). Para a realização dos ensaios, foi utilizado um motor ciclo diesel de um trator VALMET 85 id, de 58,2kW (78 cv), de acordo com metodologia estabelecida pela norma NBR 5484 da ABNT (1985) que se refere ao ensaio dinamométrico de motores de ciclo Otto e Diesel. Concluiu-se que a potência do motor ao se utilizar biodiesel foi inferior àquela quando se utilizou diesel mineral. Observou-se que, em algumas rotações, as misturas B5 e B20 apresentaram potência igual ou até superior, em algumas situações, àquela quando se utilizou diesel mineral. A melhor eficiência térmica do motor foi verificada na rotação de 540 rpm da TDP equivalente a 1720 rpm do motor.

It is considered that, in a close future, the petroleum reservations economically viable will tend to the shortage. Besides it, the exacerbated current price levels of the petroleum barrel in the international market, the possibility of employment generation and income with the consequent fixation of man country life, the excellent and varied climatic conditions and several types of terrain become the country, with extensive workable areas, stand out in the world scenery if considering its great potentiality on generation of alternative fuels. The environmental preservation, important subject nowadays, makes that the human being work in searches for the development of alternative energies, mainly those originating from renewable and biodegradable sources of sustantable character. Taking in consideration those searches, the purpose of this work was to evaluate the performance of a diesel engine working in different moments with mineral diesel and mixtures of mineral diesel and biodiesel in the equivalent proportions B2 (98 percent mineral diesel and 2 percentbiodiesel), B5 (95 percent mineral diesel and 5 percentbiodiesel), B20 (80 percent mineral diesel and 20 percentbiodiesel), and, finally, B100 (100 percent biodiesel). The rehearsal was accomplished in the dependences of the Engineering Department at UFLA - Federal University of Lavras, in Lavras, Minas Gerais, in July, 2005. For the accomplishment of the rehearsals it, was used an engine cycle diesel of a tractor VALMET 85 id, of 58,2kW (78 cv), following it methodology established by the norm NBR 5484 of ABNT (1985), that refers to the rehearsal dynamometric of engines cycle Otto and Diesel being proceeded. One noticed ended that the potency of the motor when using biodiesel was lower than one when using mineral diesel. One observed that, in some rotations, the mixtures B5 and B20 presented the same potency or even higher, in some situations, than the one when if using mineral diesel...