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Animal studies have shown exposure to diesel exhaust particles (DEPs) to induce production of reactive oxygen species (ROSs) and increase levels of 8-hydroxydeoxyquanosine (8-OHdG). Controversial results have been obtained regarding the effects of workplace exposure on urinary 8-OHdG level. This study assessed concentrations of environmental PM(2.5) in DEP (DEP(2.5)), personal DEP(2.5) and urinary 8-OHdG of diesel engine exhaust emission inspector (inspector) at a diesel vehicle emission inspection station (inspection station). The analysis specifically focuses on the factors that influence inspector urinary 8-OHdG. Repeated-measures study design was used to sample for five consecutive days. A total of 25 environmental PM(2.5) measurements were analyzed at 5 different locations by using a dichotomous sampler, and a total of 55 personal PM(2.5) measurements were analyzed from inspectors by using PM(2.5) personal sampler. During the sampling period, a total of 110 pre- and post-work urine samples from inspectors, and 32 samples from the control group were collected. Following age and sex matching between the inspectors and the control group, levels of urinary 8-OHdG were analyzed. Environmental and personal concentrations of DEP(2.5) were 107.25+/-39.76 (mean+/-SD) and 155.96+/-75.70 microg/m(3), respectively. Also, the concentration of urinary 8-OHdG differed significantly between inspector and control non-smokers, averaging 14.05+/-12.71 and 6.58+/-4.39 microg/g creatinine, respectively. Additionally, urinary 8-OHdG concentrations were associated with diesel exposure after controlling for smoking and cooking at home. Compared with the control group, the inspector displayed significantly increased levels of urinary 8-OHdG. Diesel exhaust is the single pollutant involved in the exposure of DEP(2.5) at the inspection station, as confirmed by the final results.

Exposure assessment studies for particulates have been conducted in several U.S. and European cities; however, exposure data remain sparse for Asian populations whose cultural practices and living styles are distinct from those in the developed world. This study assessed personal PM(10) exposure in urban residents and evaluated PM(10) indoor/outdoor levels in communities with different characteristics. Important factors of personal PM(10) exposure in Taiwan were explored. Sampling was conducted in 6 communities in Taiwan, two in each of the three major metropolitan areas. Up to nine non-smoking volunteers in each community carried personal samplers for 24 h. The geometric means (GM) of PM(10) in personal, indoor and outdoor samples were 76.3 microg/m(3) (geometric standard deviation, GSD=1.8), 73.4 microg/m(3) (GSD=1.5), and 85.8 microg/m(3) (GSD=1.7), respectively. It was found that outdoor levels rather than indoor levels contributed significantly to personal exposure. The important exposure factors include the time spent outdoors and on transportation, riding a motorcycle, passing by factories, cooking or being in the kitchen, and incense burning at home. Motorcycle riding and the proximity to factories are related to the special living and housing characteristics in Taiwan, while incense burning and Chinese cooking are culture-related. Motorcyclists experienced an average of 27.7 microg/m(3) higher PM(10) than others, while subjects passing by a factory were exposed to an average of 38.4 microg/m(3) higher PM(10) than others. Effective control and public education should be applied to reduce the contribution of these PM exposure sources.

Abstract: Malodor pollution emitted from industrial park has become an important environmental issue. However, the difficulty in investigating malodor pollution is in determining the malodor source. The objective of this study was to develop a model for determining the malodor source and pollution in industrial park, via multiple time and site measurements of odor intensity and air pollutants, together with wind direction in different seasons, and the critical environmental factors could be also identified by correlating the odor intensities with meteorological conditions and the concentrations of air pollutants. A high-malodor-polluted industrial park involving metal and petrochemistry processing industries was selected as the study subject, and sampling was performed close to residential districts. Nine sites were selected as sampling points by a chessboard design, with each site measured for 5days in fall and spring, respectively. Odor intensity (ratings 0–5) and environmental factors, including meteorological condition, PM10, PM2.5, total volatile organic compounds (TVOCs), ammonia and reduced sulfides, were evaluated six times daily. The results indicated that the incidences of odor ratings 1–5 were 71.9% and 81.0% in two seasons in the sampling area, and an open ditch for collecting industrial wastewater for feeding to the wastewater treatment plant was identified as the main odor source. Multiple regression analysis showed that the odor rating significantly correlated with TVOC concentration and wind speed (P<0.05); odor intensity increased by 0.001 units on the rating scale for each 1ppb increase in TVOCs, and decreased by 0.154 units for each 1m/s increase in wind speed. This study developed a method to explore malodor pollution in industrial park, providing a novel thinking to understand and resolve malodor problems. [Copyright &y& Elsevier]

Purpose: The objectives of this study were to explore the factors influencing urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels in diesel engine exhaust emission inspectors (inspectors), the association between polycyclic aromatic hydrocarbons (PAHs) exposure and fine particulate matter (PM) levels in diesel exhaust particles (DEPs), and the PAHs exposure levels in diesel vehicle emission inspection stations (inspection stations). Methods: Twenty-eight inspectors and a control group of thirty-eight individuals matched by age and gender were recruited for this study. Fifteen ambient air samples and eighty-four personal air samples were monitored during 3-day work periods using a repeated-measures study design in each inspection station. Airborne samples were analyzed with a fluorescence detector and by high-performance liquid chromatography. Urinary 8-OHdG was measured in 168 pre- and post-work urine samples from inspectors, and in 38 urine samples from controls. Results: The concentrations of PAHs in DEP (PM in DEPs) were significantly and positively related to urinary log 8-OHdG levels after adjusting for smoking status and BMI. Statistically, there was a significant correlation between air log PAHs and air log PM concentrations in inspectors. Fifteen PAHs compounds within DEP revealed the concentrations ranged from 5.18 to 22.93 ng/m in ambient air monitoring and 1.03 to 12.60 ng/m in personal air monitoring. Conclusions: This study is the first to indicate an association between occupational PAHs exposure from DEP at an inspection station and an increased excretion of urinary 8-OHdG in inspectors. In addition, this study also found smoking is not a confounder in inspectors exposed to PAHs in DEP. [ABSTRACT FROM AUTHOR]

This study attempts to determine the influence of air quality in a residential area near a medical waste incineration plant. Ambient air concentrations of polycyclic aromatic hydrocarbons (PAHs), PM10 and PM2. 5 (PM—particulate matter) were determined by collecting air samples in areas both upwind and downwind of the plant. The differences in air pollutant levels between the study area and a reference area 11km away from the plant were evaluated. Dichotomous samplers were used for sampling PM2. 5 and PM10 from ambient air. Two hundred and twenty samples were obtained from the study area, and 100 samples were taken from a reference area. Samples were weighed by an electronic microbalance and concentrations of PM2. 5 and PM10 were determined. A HPLC equipped with a fluorescence detector was employed to analyze the concentrations of 15 PAHs compounds adsorbed into PM2. 5 and PM10. The experimental results indicated that the average concentrations of PM2. 5 and PM10 were 30. 34±17. 95 and 36. 81±20. 45μgm−3, respectively, in the study area, while the average ratio of PM2. 5/PM10 was 0. 82±0. 01. The concentrations of PM2. 5 and PM10 of the study area located downwind of the incinerator were significantly higher than the study area upwind of the incinerator (P<0. 05). The concentration of PAHs in PM2. 5 in the study area was 2. 2 times higher than in the reference area (P<0. 05). Furthermore, the benzo(a)pyrene concentrations in PM2. 5 and PM10 were 0. 11±0. 05ngm−3 and 0. 12±0. 06ngm−3 in the study area, respectively. The benzo(a)pyrene concentrations of PM2. 5 and PM10 in the study area were 7 and 5. 3 times higher than in the reference area (P<0. 05), respectively. The study indicated that the air quality of PM2. 5, PM10 and PAHs had significant contamination by air pollutants emitted from a medical waste incineration factory, representing a public health problem for nearby residences, despite the factory being equipped with a modern air pollution control system. [Copyright &y& Elsevier]

Abstract: Animal studies have shown exposure to diesel exhaust particles (DEPs) to induce production of reactive oxygen species (ROSs) and increase levels of 8-hydroxydeoxyquanosine (8-OHdG). Controversial results have been obtained regarding the effects of workplace exposure on urinary 8-OHdG level. This study assessed concentrations of environmental PM2.5 in DEP (DEP2.5), personal DEP2.5 and urinary 8-OHdG of diesel engine exhaust emission inspector (inspector) at a diesel vehicle emission inspection station (inspection station). The analysis specifically focuses on the factors that influence inspector urinary 8-OHdG. Repeated-measures study design was used to sample for five consecutive days. A total of 25 environmental PM2.5 measurements were analyzed at 5 different locations by using a dichotomous sampler, and a total of 55 personal PM2.5 measurements were analyzed from inspectors by using PM2.5 personal sampler. During the sampling period, a total of 110 pre- and post-work urine samples from inspectors, and 32 samples from the control group were collected. Following age and sex matching between the inspectors and the control group, levels of urinary 8-OHdG were analyzed. Environmental and personal concentrations of DEP2.5 were 107.25±39.76 (mean±SD) and 155.96±75.70μg/m3, respectively. Also, the concentration of urinary 8-OHdG differed significantly between inspector and control non-smokers, averaging 14.05±12.71 and 6.58±4.39μg/g creatinine, respectively. Additionally, urinary 8-OHdG concentrations were associated with diesel exposure after controlling for smoking and cooking at home. Compared with the control group, the inspector displayed significantly increased levels of urinary 8-OHdG. Diesel exhaust is the single pollutant involved in the exposure of DEP2.5 at the inspection station, as confirmed by the final results. [Copyright &y& Elsevier]