Diesel Particulate Exposure Research Articles

Does increased traffic flow around unconventional resource development activities represent the major respiratory hazard to neighboring communities?: knowns and unknowns.

The objective of this review is to demonstrate that the focus on air emissions causing respiratory effects and associated with gas development may be misplaced by attributing those exposures mainly to well pad activities. The most recent publications on the health effects of hydraulic fracturing operations seem to parallel findings from studies of diesel particulate exposure near roadways and the health effects associated with those exposures. It seems at least possible that some, if not all, of the respiratory effects associated with unconventional resource development may be traffic-related. Road traffic generated by hydraulic fracturing operations is one possible source of environmental impact whose significance has, until now, been largely neglected in the available literature with 4000 to 6000 vehicles visiting the well pad. Exposures from well pads diminish rapidly with distances of only a few kilometers but there is evidence showing disease risk multiple kilometers from well pads. This leaves open the possibility that the several thousand vehicle trips per well pad create traffic emissions over wide areas away from the pad. This alternative source of exposure has not previously been well studied but is being more seriously considered.

An evaluation of diesel particulate matter in fire station vehicle garages and living quarters

Diesel particulate matter (DPM) has recently been classified as a human carcinogen by the International Agency for Research on Cancer. As a component of diesel exhaust, DPM is created from the combustion of diesel fuel. Diesel engines are commonly used in heavy duty trucks and equipment, including fire engines and ambulances. The potential for DPM migration in a fire station from an attached vehicle garage to the fire station living quarters was studied in Salt Lake County, Utah. The difference in air pressures between the living quarters and vehicle garage was measured in 24 fire stations. Of the 24 fire stations sampled, three test stations were selected based on negative air pressure test results and evidence of poor sealing doors between the living quarters and vehicle garages. These stations were the most likely to represent stations with measurable DPM within the living quarters. A control station was also sampled based on balanced air pressure test results. These selected stations were then measured for carbon concentrations in the living quarters, vehicle garages, and outdoors on two separate days. Results indicate that DPM, measured as elemental carbon, was below the limit of detection ( 3 ) for all samples with the exception of one vehicle garage sample (2.3 μg/m 3 ), which was found to be within acceptable exposure concentrations. Average total carbon concentrations for the three test stations were 44 μg/m 3 for the living area, 26 μg/m 3 for the garage and 14 μg/m 3 for the outside sample. These results suggest diesel particulate exposures are low, both within the vehicle garages and the attached living quarters.

Time course of bronchial cell inflammation following exposure to diesel particulate matter using a modified EAVES

Electrostatic deposition of particles onto the surface of well-differentiated airway cells is a rapid and efficient means to screen for toxicity associated with exposure to fine and ultrafine particulate air pollution. This work describes the development and application of an electrostatic aerosol in vitro exposure system (EAVES) with increased throughput and ease-of-use. The modified EAVES accommodates standard tissue culture plates and uses an alternating electric field to deposit a net neutral charge of aerosol onto air-interface cell cultures. Using this higher-throughput design, we were able to examine the time-course (1, 3, 6, 9, and 24h post-exposure) of transcript production and cytotoxicity in well-differentiated human bronchial cells exposed to diesel particulate matter at levels of ‘real-world’ significance. Statistically significant responses were observed at exposure levels (∼0.4μg/cm2) much lower than typically reported in vitro using traditional submerged/resuspended techniques. Levels of HO-1, IL-8, CYP1A1, COX-2, and HSP-70 transcripts increased immediately following diesel particulate exposure and persisted for several hours; cytotoxicity was increased at 24h. The modified EAVES provides a platform for higher throughput, more efficient and representative testing of aerosol toxicity in vitro.

Chronic traffic pollution exposure is associated with eosinophilic, but not neutrophilic inflammation in older adult asthmatics

Objective: Airway inflammatory patterns in older asthmatics are poorly understood despite high asthma-related morbidity and mortality. In this study, we sought to define the relationship between exposure to traffic pollutants, biomarkers in induced sputum, and asthma control in older adults. Methods: Induced sputum was collected from 35 non-smoking adults ≥65 years with a physician’s diagnosis of asthma and reversibility with a bronchodilator or a positive methacholine challenge. Patients completed the Asthma Control Questionnaire (ACQ), and Elemental Carbon Attributable to Traffic (ECAT), a surrogate for chronic diesel particulate exposure, was determined. Equal numbers of subjects with high (≥0.39 µg/m3) versus low (<0.39 µg/m3) ECAT were included. Differential cell counts were performed on induced sputum, and myeloperoxidase (MPO) and eosinophil peroxidase (EPO) were measured in supernatants. Regression analyses were used to evaluate the relationship between sputum findings, ACQ scores, and ECAT. Results: After adjustment for potential confounders, subjects with poorly controlled asthma based on ACQ ≥ 1.5 (n = 7) had significantly higher sputum eosinophils (median = 4.4%) than those with ACQ < 1.5 (n = 28; eosinophils = 2.6%; β = 10.1 [95% CI = 0.1–21.0]; p = 0.05). Subjects with ACQ ≥ 1.5 also had significantly higher sputum neutrophils (84.2% versus 65.2%; β = 7.1 [0.2–14.6]; p = 0.05). Poorly controlled asthma was associated with higher sputum EPO (β = 2.4 [0.2–4.5], p = 0.04), but not MPO (p = 0.9). High ECAT was associated with higher eosinophils (β = 10.1 [1.8–18.4], p = 0.02) but not higher neutrophils (p = 0.6). Conclusions: Poorly controlled asthma in older adults is associated with eosinophilic and neutrophilic inflammation. Chronic residential traffic pollution exposure may be associated with eosinophilic, but not neutrophilic inflammation in older asthmatics.

Diesel particulate exposure and diabetes mortality among workers in the Ontario construction trades

Diesel particulate exposure and diabetes mortality among workers in the Ontario construction trades

Importance of neutral endopeptidase in epithelial response to diesel particulate exposure

Importance of neutral endopeptidase in epithelial response to diesel particulate exposure

98/02464 An overview of diesel particulate exposures and control technology in the U.S. mining industry : Haney, R. A. et al. Appl. Occup. Environ. Hyg., 1997, 12, (12), 1013–1018

98/02464 An overview of diesel particulate exposures and control technology in the U.S. mining industry : Haney, R. A. et al. Appl. Occup. Environ. Hyg., 1997, 12, (12), 1013–1018

An Overview of Diesel Particulate Exposures and Control Technology in the U.S. Mining Industry

Abstract Studies of diesel particulate exposures in the U.S. mining industry indicate that diesel particulate exposures in surface mining operations are generally less than 0.2 mg/m3. Average diesel particulate exposures in underground coal mines using diesel-powered equipment ranged from 0.1 to 2.1 mg/m3. Average diesel particulate exposures in underground metal and nonmetal mines ranged from 0.3 to 1.6 mg/m3. The purpose of this article is to provide an overview on worker exposure to diesel particulate matter (DPM) and to discuss the effect of control technology on that exposure. Worker exposure has been assessed from in-mine diesel particulate measurements. The effect of control technology has been evaluated by a systems approach, which includes engine emission rate, mine ventilation system, and the effectiveness of engine aftertreatment devices. Studies conducted by the Mine Safety and Health Administration and the Bureau of Mines show that the primary means currently employed by the mining industry t...

97/02382 Results of underground mine studies to assess diesel particulate exposures and control technologies

Among the anthropogenic topographic signatures on Earth, open-pit mines are of great importance. Mining is of interest to geomorphologists and environmental researchers because of its implication in geomorphic hazards and processes. In addition, open-pit mines and quarries are considered the most dangerous industrial sector, with injuries and accidents occurring in numerous countries. Their fast, accurate and low-cost investigation, therefore, represents a challenge for the Earth science community. The purpose of this work is to characterise the open-pit mining features using high-resolution topography and a recently published landscape metric, the Slope Local Length of Auto-Correlation (SLLAC) (Sofia et al., 2014). As novel steps, aside from the correlation length, the terrace’s orientation is also calculated, and a simple empirical model to derive the percentage of artificial surfaces is tested. The research focuses on two main case studies of iron mines, both located in the Beijing district (P.R. China). The main topographic information (Digital Surface Models, DSMs) was derived using an Unmanned Aerial Vehicle (UAV) and the Structure from Motion (SfM) photogrammetric technique. The results underline the effectiveness of the adopted methodologies and survey techniques in the characterisation of the main mine’s geomorphic features. Thanks to the SLLAC, the terraced area given by open-cast/open-pit mining for iron extraction is automatically depicted, thus, allowing researchers to quickly estimate the surface covered by the open-pit. This information could be used as a starting point for future research (i) given the availability of multi-temporal surveys to track the changes in the extent of the mine; (ii) to relate the extent of the mines to the amount of processes in the area (e.g. pollution, erosion, etc.), and to (iii) combine the two points, and analyse the effects of the change related to changes in erosion. The analysis of the correlation length orientation also allows researchers to identify the terrace’s orientation and to understand the shape of the open-pit area. The tectonic environment and history, or inheritance, of a given slope can determine if and how it fails, and the orientation of the topographic surface or excavation face, with respect to geologic features, is of major significance. Therefore, the proposed approach can provide a basis for a large-scale and low-cost topographic survey for sustainable environmental planning and, for example, for the mitigation of environmental anthropogenic impacts due to mining.

In Mine Comparison of Diesel Particulate Sampling Methods

Abstract In an effort to quantify diesel particulate exposures in the mining industry, various organizations have developed diesel particulate sampling instruments. These instruments work on a variety of different principles. These principles include the use of size-selective sampling utilizing inertial impaction, the measurement of respirable combustible dust (RCD), and the measurement of elemental carbon. The RCD methods provide measurements of whole diesel particulate. The size-selective and elemental carbon methods provide a measurement of a fraction of the diesel particulate matter. The size-selective and RCD methods are limited by gravimetric analysis. The elemental carbon method is limited by filter loading. A series of tests were conducted to compare the measurements obtained with the various diesel particulate sampling instruments and analytical methods. The tests were conducted at two underground mining facilities, a zinc mine and a potash mine. Similar tests are scheduled to be conducted in coa...

Effect of diesel particulate exposure on adenylate and guanylate cyclase of rat and guinea pig liver and lung.

An examination of the effects of 250 or 1500 micrograms m-3 concentrations of diesel particulate from diesel exhaust on the activity of adenylate or guanylate cyclase was undertaken using liver and lung tissue of rats and guinea pigs. These membrane and cytosolic enzymes were selected to screen for functional or regulatory alterations in these tissues. The studies for adenylate cyclase used the microsomal membrane fraction of each tissue; for guanylate cyclase, the microsomal membrane and supernate fractions were used. Basal and fluoride-stimulated adenylate cyclase activity were measured. Basal and sodium azide-stimulated guanylate cyclase activity were also determined. The basal activity of rat liver adenylate cyclase is generally unchanged throughout 52 weeks of diesel exposure. Stimulated adenylate cyclase shows an age-related decrease for all animal treatments throughout the study. Changes in enzyme activity occurred at 12 weeks and 52 weeks after 1500 micrograms m-3 exposure. Soluble stimulated guinea pig lung guanylate cyclase was first increased (6 weeks) and then decreased (24 weeks) by diesel exposure. At 52 weeks, there was no change. The data suggest the following trends: (1) an increased basal adenylate cyclase in the rat lung; (2) an age-related decrease in adenylate cyclase activity in rat liver, and (3) a biphasic exposure-related response of soluble guanylate cyclase for the guinea pig lung during the first 24 weeks, but no change at 52 weeks. In general, however, these studies suggest that diesel exposure does not substantially alter either of these intracellular regulating enzymes.

Characterization of diesel particulate exposure

This report summarizes our work on the physical and chemical characterization of diesel exhaust with emphasis on the extractable and benzo( a)pyrene content of the particulate. Compared with benzene-ethanol, methylene chloride is an unsuitable extraction solvent for the measurement of benzo( a)pyrene in diesel particulate. Using recently developed analytical techniques, a series of studies of sampling parameters shows that the composition of the particulate is fixed when it leaves the tailpipe and that the composition does not change with dilution. Further, sampling results in a dilution tunnel agree quite well with those observed in open air sampling. Finally, based on various air quality models and projections of the diesel sales-emission scenario, we find that the light-duty diesel will be a minor contributor to total ambient particulate.