Analysis of particle and vapour phase PAHs from the personal air samples of bus garage workers exposed to diesel exhaust. (33/398)

The levels of particle and vapour phase polycyclic aromatic hydrocarbons (PAHs) derived from the diesel exhaust compounds in bus garage work were measured in winter and in summer. Five personal air samples were collected from the breathing zones of 22 garage workers every other day of consecutive weeks. Control samples (n = 22) were collected from office workers in Helsinki. Fifteen PAHs in the air samples were analysed by HPLC using a fluorescence detector. Statistically significant differences were observed between total PAH levels of the exposed workers (2241 and 1245 ng/m(3)) and the control group (254 and 275 ng/m(3)) in both winter (P < 0.001) and summer (P < 0.001). Phenanthrene, pyrene, benzo[ghi]perylene and fluoranthene were the major compounds in the particle phase, and naphthalene, phenanthrene and fluorene in the vapour phase. About 98% of PAHs measured were related to the vapour phase compounds, whereas the high molecular weight PAH compounds were detected only in the particle phase. The PAH levels in the garages were twice as high (P < 0.001) in winter as in summer. Even though the exposure levels were low in the bus garages, the low level does not allow conclusions to be drawn about the possible adverse health effects due to exposure to diesel exhaust.  (+info)

Using human activity data in exposure models: analysis of discriminating factors. (34/398)

This paper tests factors thought to be important in explaining the choices people make in where they spend time. Three aggregate locations are analyzed: outdoors, indoors, and in-vehicles for two different sample groups: a year-long (longitudinal) sample of one individual and a cross-sectional sample of 169 individuals from the US Environmental Protection Agency's Consolidated Human Activity Database (CHAD). The cross-sectional sample consists of persons similar to the longitudinal subject in terms of age, work status, education, and residential type. The sample groups are remarkably similar in the time spent per day in the tested locations, although there are differences in participation rates: the percentage of days frequenting a particular location. Time spent outdoors exhibits the most relative variability of any location tested, with in-vehicle time being the next. The factors found to be most important in explaining daily time usage in both sample groups are: season of the year, season/temperature combinations, precipitation levels, and day-type (work/nonwork is the most distinct, but weekday/weekend is also significant). Season, season/temperature, and day-type are also important for explaining time spent indoors. None of the variables tested are consistent in explaining in-vehicle time in either the cross-sectional or longitudinal samples. Given these findings, we recommend that exposure modelers subdivide their population activity data into at least season/temperature, precipitation, and day-type "cohorts" as these factors are important discriminating variables affecting where people spend their time.  (+info)

The relationship between air pollution from heavy traffic and allergic sensitization, bronchial hyperresponsiveness, and respiratory symptoms in Dutch schoolchildren. (35/398)

Studies have suggested that children living close to busy roads may have impaired respiratory health. This study was designed to test the hypothesis that exposure to exhaust from heavy traffic in particular is related to childhood respiratory health. Children attending 24 schools located within 400 m from busy motorways were investigated. The motorways carried between 5,190 and 22,326 trucks per weekday and between 30,399 and 155,656 cars per day. Locations were chosen so that the correlation between truck and car traffic counts was low. Air pollution measurements were performed at the schools for 1 year. Respiratory symptoms were collected by parent-completed questionnaire. Sensitization to common allergens was measured by serum immunoglobulin E and skin prick tests. Bronchial hyperresponsiveness (BHR) was measured with a hypertonic saline challenge. Respiratory symptoms were increased near motorways with high truck but not high car traffic counts. They were also related to air pollutants that increased near motorways with high truck traffic counts. Lung function and BHR were not related to pollution. Sensitization to pollen increased in relation to truck but not car traffic counts. The relation between symptoms and measures of exposure to (truck) traffic-related air pollution were almost entirely restricted to children with BHR and/or sensitization to common allergens, indicating that these are a sensitive subgroup among all children for these effects.  (+info)

New roads and human health: a systematic review. (36/398)

We sought to synthesize evidence of the health effects of construction of new roads by systematically reviewing observational studies of such effects. We included and critically appraised 32 studies. The review suggested that out-of-town bypasses decrease injuries on main roads through or around towns, although more robust evidence is needed on effects on secondary roads. New major urban roads have statistically insignificant effects on injury incidence. New major roads between towns decrease injuries. Out-of-town bypasses reduce disturbance and community severance in towns but increase them elsewhere. Major urban roads increase disturbance and severance. More robust research is needed in this area, particularly regarding effects of new roads on respiratory health, mental health, access to health services, and physical activity.  (+info)

Influence of traffic patterns on particulate matter and polycyclic aromatic hydrocarbon concentrations in Roxbury, Massachusetts. (37/398)

Vehicle emissions have been associated with adverse health effects in multiple epidemiological studies, but the sources or constituents responsible have not been established. Characterization of vehicle-related exposures requires detailed information on spatial and temporal trends of various pollutants and the ability to predict exposures in unmonitored settings. To address these issues, in the summer of 2001 we measured continuously particle-bound polycyclic aromatic hydrocarbons (PAHs), ultrafine particles, and PM(2.5) at a number of sites in Roxbury, a neighborhood of Boston, Massachusetts with significant diesel and gasoline-fueled traffic. We took measurements at the side of the road and at varying distances from the road, with simultaneous collection of traffic counts and meteorological conditions. Across all nine sites, median roadside concentrations were 8 ng/m(3) of particle-bound PAHs (range: 4-57), 16,000 ultrafine particles/cm(3) (range: 11,000-53,000), and 54 microg/m(3) of PM(2.5) as measured with a DustTrak (range: 12-86). Concentrations of all pollutants were lower at greater distances from the road, upwind, and at higher wind speeds, with greater concentration gradients for PAHs and ultrafine particles. In linear mixed effects regression models accounting for temporal autocorrelation, large diesel vehicle counts were significantly associated with roadside concentrations of PAHs (P=0.02), with a moderate association with ultrafine particles and little relation with PM(2.5). Although more comprehensive information would be needed for epidemiological applications, these data demonstrate significant spatial and temporal heterogeneity for traffic-related pollutants during the summer in an urban center, with our monitoring and analytical methodology helping to inform source attribution.  (+info)

Working conditions and health of the employees of public bus and trolleybus transport in Lithuania. (38/398)

A questionnaire was used for investigation of 788 workers from three transport enterprises. The questionnaire was used for evaluation of occupational environment, lifestyle, psychosocial factors and self-evaluation of health. The most harmful occupational factors are unsatisfactory microclimatic conditions, diesel fuel, cooling oil, vibration, musculoskeletal load, and mental tension. Worker's lifestyle isn't healthy: 46% of them are smoking, 83% are drinking alcohol, 53% are physically inactive, 82% have bad nutrition regimen, 27% are everyday suffering from stressful situations. Main health impairments are musculoskeletal (46.2%), respiratory tract (22.2%), gastrointestinal (17.3%) and central nervous system (32.2%) diseases. Musculoskeletal disorders are statistically related to bad ergonomic work conditions, long workday hours, aged employees and long work experience of workers (p<0.05-0.002).  (+info)

Risk of congenital anomalies in the vicinity of municipal solid waste incinerators. (39/398)

BACKGROUND: Although municipal solid waste incineration (MSWI) has contributed to increase the overall environmental load of particulate matter containing dioxins and metals, evidence of health consequences to populations is sparse. AIMS: To assess at a regional level (in southeast France) the impact of these emissions on birth defect rates. METHODS: Communities with fewer than 50 000 inhabitants surrounding the 70 incinerators that operated at least one year from 1988 to 1997 were studied. Each exposed community (n = 194) was assigned an exposure index estimated from a Gaussian plume model. Poisson models and a reference population of the 2678 unexposed communities in the region were used to calculate relative risks for congenital malformations, adjusted for year of birth, maternal age, department of birth, population density, average family income, and when available, local road traffic. RESULTS: The rate of congenital anomalies was not significantly higher in exposed compared with unexposed communities. Some subgroups of major anomalies, specifically facial clefts and renal dysplasia, were more frequent in the exposed communities. Among exposed communities, a dose-response trend of risk with increasing exposure was observed for obstructive uropathies. Risks of cardiac anomalies, obstructive uropathies, and skin anomalies increased linearly with road traffic density. CONCLUSIONS: Although both incinerator emissions and road traffic may plausibly explain some of the excess risks observed, several alternative explanations, including exposure misclassification, ascertainment bias, and residual confounding cannot be excluded. Some of the effects observed, if real, might be attributable to old-technology MSWIs and the persistent pollution they have generated.  (+info)

Missing cyclists. (40/398)

OBJECTIVES: (1) For crashes on a public road, to compare serious cyclist crashes involving a motor vehicle with cyclist crashes not involving a motor vehicle, in terms of threat to life and length of stay in hospital. (2) To determine the proportion of all serious crashes involving cyclists on public roads which are recorded by the police. (3) To determine the degree to which under-reporting of serious crashes involving cyclists and motor vehicles on public roads is associated with various demographic, environmental, and injury factors. STUDY DESIGN: Records for the period 1995-99, of cyclists seriously injured on a public road and hospitalised were linked to the traffic crash report (TCR) database maintained by Land Transport Safety Authority (LTSA). RESULTS: Of the 2925 cyclist crashes on public roads, only 652 (22%) could be linked to a TCR. Of the crashes involving motor vehicles (n = 1033), only 562 (54%) could be linked to the LTSA database. Age, ethnicity, injury severity, and cumulative length of stay were the only variables that predicted whether hospitalised cycle crash cases were more likely to have a corresponding TCR. There were substantial numbers of cyclist only crashes which typically are not captured in the TCR database. Nine percent of these resulted in serious or worse injury (that is, International Classification of Diseases/abbreviated injury scale score of 3+) and 7% resulted in hospital stays greater than seven days. CONCLUSION: Greater effort and precision needs to be applied to routinely document the burden of cyclist crashes, especially cyclist only crashes.  (+info)