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Although the particulate matter (PM) emissions from biodiesel fuelled engines are acknowledged to be lower than those of fossil diesel, there is a concern on the impact of PM produced by biodiesel to human health. As the oxidative potential of PM has been suggested as trigger for adverse health effects, it was measured using the Electron Spin Resonance (OP(ESR)) technique. Additionally, Energy Dispersive X-ray Fluorescence Spectroscopy (EDXRF) was employed to determine elemental concentration, and Raman Spectroscopy was used to describe the amorphous carbon character of the soot collected on exhaust PM from biodiesel blends fuelled test-bed engine, with and without Selective Catalytic Reduction (SCR). OP(ESR) results showed higher oxidative potential per kWh of PM produced from a blend of 20% soybean biodiesel and 80% ULSD (B20) engine compared with a blend of 5% soybean biodiesel and 95% ULSD (B5), whereas the SCR was able to reduce oxidative potential for each fuel. EDXRF data indicates a correlation of 0.99 between concentration of copper and oxidative potential. Raman Spectroscopy centered on the expected carbon peaks between 1100cm(-1) and 1600cm(-1) indicate lower molecular disorder for the B20 particulate matter, an indicative of a more graphitic carbon structure. The analytical techniques used in this study highlight the link between biodiesel engine exhaust and increased oxidative potential relative to biodiesel addition on fossil diesel combustion. The EDXRF analysis confirmed the prominent role of metals on free radical production. As a whole, these results suggest that 20% of biodiesel blends run without SCR may pose an increased health risk due to an increase in OH radical generation., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objective: To analyze ovarian and uterine morphologic changes resulting from intrauterine and postnatal exposure to diesel exhaust., Design: Crossover study. Experimental groups: intrauterine and postnatal clean air exposure; intrauterine exposure to diesel only; postnatal exposure to diesel only; and intrauterine and postnatal exposure to diesel., Setting: Laboratory of Experimental Air Pollution., Animal(s): Swiss mice., Intervention(s): Mice exposed to diesel exhaust with doses that correspond to the daily average PM₂.₅ levels (fine particles in the ambient air 2.5 μm or less in size) reported by the World Health Organization., Main Outcome Measure(s): Morphometric analyses of the ovaries and uterus were performed to define the relative area occupied by follicles, corpus luteum, and stroma and the proportionate area of glands, epithelial layer, and stroma within the uterine endometrium., Result(s): A significant reduction in the proportion of primordial follicles was observed in intrauterine-exposed animals, those exposed during the postnatal period, and in animals exposed during both phases. Primary follicle proportion was reduced in animals exposed during pregnancy. No significant changes were detected in uterine morphology., Conclusion(s): Intrauterine exposure to acceptable levels of diesel exhaust compromises the reproductive potential of female mice, diminishing ovarian reserve when sexual maturity is achieved. This effect could increase the risk of premature menopause. The findings raise concern about current environmental guidelines for diesel exposure, warranting more careful examination of this issue in humans by regulatory authorities., (Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Non-mechanised sugarcane harvesting preceded by burning exposes workers and the people of neighbouring towns to high concentrations of pollutants. This study was aimed to evaluate the respiratory symptoms, lung function and oxidative stress markers in sugarcane workers and the residents of Mendonça, an agricultural town in Brazil, during the non-harvesting and harvesting periods and to assess the population and individual exposures to fine particulate matter (PM(2.5)). Sugarcane workers and healthy volunteers were evaluated with two respiratory symptom questionnaires, spirometry, urinary 1-hydroxypyrene levels, and the measurement of antioxidant enzymes and plasma malonaldehyde during the non-harvesting and harvesting periods. The environmental assessment was determined from PM(2.5) concentration. PM(2.5) level increased from 8 μg/m³ during the non-harvesting period to 23.5 μg/m³ in the town and 61 μg/m³ on the plantations during the harvesting period. Wheezing, coughing, sneezing, and breathlessness increased significantly in both groups during the harvesting period, but more markedly in workers. A decrease in lung function and antioxidant enzyme activity was observed in both populations during harvesting; this decrease was greater among the sugarcane workers. The urinary 1-hydroxypyrene levels only increased in the sugarcane workers during the harvesting period. The malonaldehyde levels were elevated in both groups, with a higher increase observed in the workers. This research demonstrates the exposure of sugarcane workers and the inhabitants of a neighbouring town to high PM(2.5) concentrations during the sugarcane harvest period. This exposure was higher among the sugarcane workers, as illustrated by both higher PM(2.5) concentrations in the sugarcane fields and higher urinary 1-hydroxypyrene levels in the volunteers in this group. The higher incidence of respiratory symptoms, greater decrease in lung function and more marked elevation of oxidative stress markers among the sugarcane workers during the harvest confirms the greater effect magnitude in this population and a dose-dependent relationship between pollution and the observed effects., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Brazil contains 25% of the total land planted with sugarcane in the world and is thus one of the major producers. The annual burning of sugarcane fields prior to harvesting emits huge amounts of pyrogenic particles. Biomass burning is an important primary and secondary source of aerosol particles. The presence of carbonaceous particles in the inhalable size range makes it important to study this fraction in view of the possible effects on human health and the climate. In this study, the mutagenic activity associated with inhalable airborne particulate matter (PM(10)) collected on air filters in a sugarcane-growing area near the city of Araraquara (SE Brazil) was determined. The extracts were dissolved in dimethylsulfoxide and tested for mutagenicity by the Ames plate incorporation test with Salmonella typhimurium YG1024 in the presence and absence of the S9 mixture. To assess the association between mutagenicity and PM(10), samples were collected in sugarcane harvesting and non-harvesting periods of the year. Significant mutagenicity was detected in organic solvent extracts of all samples, with differences between the two periods. The highest values of mutagenic potency (13.45 and 5.72 revertants/m(3) of air in the absence and presence of the S9 mixture, respectively) were observed during the harvest. In this period, a Teflon™-coated glass-fiber air filter trapped 67.0 μg of particulate matter per m(3) of air. In the non-harvest period, on the same type of filter, only 20.9 μg of particulate matter was found per m(3). The mutagenic potencies at this time were 1.30 and 1.04 revertants/m(3) of air, in the absence and presence of the S9 mixture, respectively. Period, concentration of PM(10) and mutagenicity were associated with each other. For routine monitoring of mutagenicity in the atmosphere, the use of YG1024 tester strain without metabolic activation (S9) is recommended., (Copyright © 2011 Elsevier Inc. All rights reserved.)