An analysis of factors that influence personal exposure to toluene and xylene in residents of Athens, Greece

BACKGROUND: Personal exposure to pollutants is influenced by various outdoor and indoor sources. The aim of this study was to evaluate the exposure of Athens citizens to toluene and xylene, excluding exposure from active smoking. METHODS: Passive air samplers were used to monitor volunteers, their homes and various urban sites for one year, resulting in 2400 measurements of toluene and xylene levels. Since both indoor and outdoor pollution contribute significantly to human exposure, volunteers were chosen from occupational groups who spend a lot of time in the streets (traffic policemen, bus drivers and postmen), and from groups who spend more time indoors (teachers and students). Data on individual and house characteristics were obtained using a questionnaire completed at the beginning of the study; a time-location-activity diary was also completed daily by the volunteers in each of the six monitoring campaigns. RESULTS: Average personal toluene exposure varied over the six monitoring campaigns from 53 to 80 μg/m(3). Urban and indoor concentrations ranged from 47 – 84 μg/m(3 )and 30 – 51 μg/m(3), respectively. Average personal xylene exposure varied between 56 and 85 μg/m(3 )while urban and indoor concentrations ranged from 53 – 88 μg/m(3 )and 27 – 48 μg/m(3), respectively. Urban pollution, indoor residential concentrations and personal exposures exhibited the same pattern of variation during the measurement periods. This variation among monitoring campaigns might largely be explained by differences in climate parameters, namely wind speed, humidity and amount of sunlight. CONCLUSION: In Athens, Greece, the time spent outdoors in the city center during work or leisure makes a major contribution to exposure to toluene and xylene among non-smoking citizens. Indoor pollution and means of transportation contribute significantly to individual exposure levels. Other indoor residential characteristics such as recent painting and mode of heating used might also contribute significantly to individual levels. Groups who may be subject to higher exposures (e.g. those who spent more time outdoors because of occupational activities) need to be surveyed and protected against possible adverse health effects

Effect of biodiesel origin on regulated and particle-bound PAH (polycyclic aromatic hydrocarbon) emissions from a Euro 4 passenger car

This study investigates the impact of mid-high biodiesel blends on the criteria and PAH emissions from a pick-up diesel vehicle. The vehicle was a Euro 4 (category N1, subclass III) compliant common rail light duty vehicle fitted with a diesel oxidation catalyst. Emission and fuel consumption measurements were performed on a chassis dynamometer using constant volume sampling (CVS) technique, following the European regulations. All measurements were conducted over the NEDC and Artemis driving cycles. Aiming to evaluate the fuel impact on emissions, a soy-based biodiesel, a palm-based biodiesel, and an oxidized biodiesel obtained from used frying oils were blended with an ultra low sulfur diesel at proportions of 30%, 50% and 80% by volume. CO2 emissions and fuel consumption exhibited increases with biodiesel over all driving conditions which ranged up to 5%. NOx emissions were found to be above the Euro 4 limit and increased with biodiesel between 5% and 10% except for the blends prepared with the palm-based methyl ester. The emissions of PM, HC, and CO decreased with the addition of biodiesel reaching maximum reductions in the order of 10%, 30% and 20% respectively; however, some increases were observed over the NEDC which may be attributed to cold-start. Sharp increases in most PAH, nitro-PAH and oxy- PAH compounds were observed with the application of biodiesel. These increases were particularly noticeable with the use of the oxidized blends, a phenomenon that it is related with the type and quality of this fuel. The emissions were also affected by the operating conditions of the engine. It was found that most PAH compounds were decreased as the mean speed and load of the driving cycle increased.JRC.F.9-Sustainable Transport (Ispra

An Experimental Study on the Impact of Biodiesel Origin on the Regulated and PAH Emissions from a Euro 4 light-duty Vehicle

This study investigates the impact of mid-high biodiesel blends on the criteria and PAH emissions from a pick-up diesel vehicle. The vehicle was a Euro 4 (category N1, subclass III) compliant common rail light duty vehicle fitted with a diesel oxidation catalyst. Emission and fuel consumption measurements were performed on a chassis dynamometer using constant volume sampling (CVS) technique, following the European regulations. All measurements were conducted over the NEDC and Artemis driving cycles. Aiming to evaluate the fuel impact on emissions, a soy-based biodiesel, a palm-based biodiesel, and an oxidized biodiesel obtained from used frying oils were blended with an ultra low sulfur diesel at proportions of 30%, 50% and 80% by volume. CO2 emissions and fuel consumption exhibited increases with biodiesel over all driving conditions which ranged up to 5%. NOx emissions were found to be above the Euro 4 limit and increased with biodiesel between 5% and 10% except for the blends prepared with the palm-based methyl ester. The emissions of PM, HC, and CO decreased with the addition of biodiesel reaching maximum reductions in the order of 10%, 30% and 20% respectively; however, some increases were observed over the NEDC which may be attributed to cold-start. Sharp increases in most PAH, nitro-PAH and oxy- PAH compounds were observed with the application of biodiesel. These increases were particularly noticeable with the use of the oxidized blends, a phenomenon that it is related with the type and quality of this fuel. The emissions were also affected by the operating conditions of the engine. It was found that most PAH compounds were decreased as the mean speed and load of the driving cycle increased.JRC.F.9-Sustainable Transport (Ispra

A 2-(2’-pyridyl)quinoline ruthenium(II) complex as an active catalyst for the transfer hydrogenation of ketones

The ruthenium(II) complex cis-[RuCl2(PPh3)2(L1)] (1) where L1 = 2-(2’-pyridyl)quinoline was obtained in high yield from the reaction of [RuCl2(PPh3)3] with L1. The new compound was characterized by different spectroscopic methods including FT-IR, UV-Vis, NMR (1H, 31P) spectroscopy along with a mass spectrometric analysis (ESI-MS) and conductivity measurements. 31P NMR spectroscopy provided evidence that the two PPh3 ligands are orientated trans to each other in an octahedral environment. Complex (1) was tested in the transfer hydrogenation of various ketones in 2-propanol at 82 oC. The catalytic activity of (1) displayed quantitative conversions for benzophenone and 4-chloroacetophenone

Occurrence and Distribution of Polycyclic Aromatic Hydrocarbons in the Marine Surface Microlayer of an Industrialized Coastal Area in the Eastern Mediterranean

Concentrations of dissolved and particulate polycyclic aromatic hydrocarbons (PAHs) were determined seasonally in sea surface microlayer (SML) and sub-surface water (SSW) within the Saronicos Gulf, Greece, close to a highly industrialized coastal zone. For the 16 US EPA priority PAHs, the sum of dissolved PAHs (∑dPAHs) concentrations ranged from 40.4 to 237 ng L−1 in SML, 22.8–180 ng L−1 in SSW0.2, whereas the corresponding concentrations in suspended particulate matter (∑pPAHs) were 30.8 to 177 ng L−1 and 36.8–171 ng L−1, respectively. The enrichment factor (EF) for dissolved ∑dPAHs varied from 0.9 to 2.1 with a mean value of 1.5 (n = 10) being statistically significantly greater than unity, whereas for particulate ∑pPAHs, no enrichment of the SML was reported. Enrichment factors of 5–6 ring PAHs were higher near the industrial zone. The possible sources, fate, and toxicity of PAHs are also discussed

Occurrence and Distribution of Polycyclic Aromatic Hydrocarbons in the Marine Surface Microlayer of an Industrialized Coastal Area in the Eastern Mediterranean

Concentrations of dissolved and particulate polycyclic aromatic hydrocarbons (PAHs) were determined seasonally in sea surface microlayer (SML) and sub-surface water (SSW) within the Saronicos Gulf, Greece, close to a highly industrialized coastal zone. For the 16 US EPA priority PAHs, the sum of dissolved PAHs ( n-ary sumation (d)PAHs) concentrations ranged from 40.4 to 237 ng L-1 in SML, 22.8-180 ng L-1 in SSW0.2, whereas the corresponding concentrations in suspended particulate matter ( n-ary sumation (p)PAHs) were 30.8 to 177 ng L-1 and 36.8-171 ng L-1, respectively. The enrichment factor (EF) for dissolved n-ary sumation (d)PAHs varied from 0.9 to 2.1 with a mean value of 1.5 (n = 10) being statistically significantly greater than unity, whereas for particulate n-ary sumation (p)PAHs, no enrichment of the SML was reported. Enrichment factors of 5-6 ring PAHs were higher near the industrial zone. The possible sources, fate, and toxicity of PAHs are also discussed