Traffic related air pollution in city districts near motorways.
Traffic related air pollution near major motorways was measured and results are presented.
Air Pollution↗
Biomedical subjects
H Harssema
Publications and source records attributed to H Harssema.
Mass concentration and elemental composition of PM10 in classrooms.
OBJECTIVES: To investigate the sources of high concentrations of particles of < 10 microns diameter (PM10) in classrooms, observed in a previous study on childhood exposure to PM10, and to study the correlation between classroom and outdoor concentrations of mass and elements of PM10. METHODS: Measurements of PM10 were conducted in two schools and outdoors in Amsterdam, the Netherlands. Averaging time was 24 hours for the outdoor measurements and both 8 hours (school time) and 24 hours for the classroom measurements. Analysis by x ray fluorescence was used to measure the elemental composition of 55 samples from the 11 days when measurements were conducted simultaneously in both classrooms and outdoors. RESULTS: For most elements, classroom concentrations were considerably higher than outdoor concentrations, especially during school hours. The highest classroom/outdoor ratios were found for the elements from soils Si, Ca, and Ti. The only measured elements that were not increased were S, Br, Pb, and Cl, which are dominated by non-crustal sources. For S, Br, and Pb, which are generally associated with particles < 1 micron, significant correlations between classroom and outdoor concentrations and between the two classrooms were found. The other elements generally had low correlations. CONCLUSIONS: The results show that the high PM10 concentrations found in our classrooms are probably due to resuspension of coarse particles or suspension of soil material. Due to these excess coarse particles, the correlation between classroom and outdoor concentrations is lower for elements associated with coarse particles than for elements associated with fine particles. As the general composition of PM10 in classrooms differs from the composition of PM10 in ambient air, the high PM10 mass concentrations in classrooms can probably not be directly compared with ambient air quality guidelines.
Air Pollutants↗
Personal sampling of particles in adults: relation among personal, indoor, and outdoor air concentrations.
To investigate the validity of outdoor particulate matter with a 50% cutoff diameter of 10-microm (PM10) concentrations as a measure of exposure in time series studies, the association between personal and outdoor concentrations, within subjects, over time was investigated. Repeated measurements of personal, indoor, and outdoor PM10 were conducted among 37 nonsmoking, 50- to 70-year-old adults, living in Amsterdam, Netherlands, 1994. Regression analyses were conducted for each subject separately, and the distribution of the individual regression and correlation coefficients was investigated. Furthermore, the extent to which differences among personal, indoor, and outdoor concentrations could be explained was studied. The median Pearson's R between personal and outdoor concentrations was 0.50. Excluding days with exposure to environmental tobacco smoke (ETS) improved the correlation to a median R of 0.71. The estimated cross-sectional correlations were lower, 0.34 and 0.50, respectively. Outdoor concentrations (mean, 42 microg/m3) exceeded indoor concentrations (mean, 35 microg/m3) but underestimated personal exposures (mean, 62 microg/m3). The major part of the difference between personal and outdoor concentrations could be attributed to exposure to ETS, living along a busy road, and time spent in a vehicle. The results show a reasonably high correlation between personal and outdoor PM10 within individuals, providing support for the use of ambient PM10 concentrations as a measure of exposure in epidemiologic studies linking the day-to-day variation in particulate matter air pollution to the day-to-day variation in health endpoints such as mortality, hospital admissions, respiratory symptoms, and lung function.
Aged↗
[Relationship between air pollution due to traffic, decreased lung function and airway symptoms in children].
OBJECTIVE: To assess whether air pollution by traffic was related to lung function and chronic respiratory symptoms in children living. DESIGN: Descriptive. SETTING: The province of South Holland, the Netherlands. METHODS: In the period May through July of 1995 pulmonary function tests and questionnaires were obtained from 1,092 and 1,068 children respectively in six city districts near busy motorways in the province of South Holland. In the same period, indoor measurements were performed at 12 schools of NO2, black smoke and PM10 dust density. Lung function data were analysed by multiple linear regression and respiratory symptoms were analysed by multiple logistic regression. As independent variables, distance between motorway and home, passenger car traffic density and lorry traffic density on the motorway, and black smoke and NO2 concentrations in schools were taken. RESULTS: Significant differences in lung function and respiratory symptoms were found between children living in different city districts. Lung function as well as symptoms were associated with lorry traffic density on the motorway. The validity of these findings was supported by associations between black smoke concentrations (representative for diesel soot) and lung function as well as respiratory symptoms. In contrast, there was no association between passenger car traffic counts or NO2 and lung function or respiratory symptoms. CONCLUSION: The results suggest that air pollution by lorry traffic can lead to reduced lung function and to an increased prevalence of chronic respiratory symptoms in children living near major motorways.
Air Pollutants↗
Motor vehicle exhaust and chronic respiratory symptoms in children living near freeways.
To examine whether motor vehicle exhaust from freeways has an effect on respiratory health of children, a cross-sectional study was conducted. Children attending schools situated less than 1000 m from major freeways in the Province of South Holland were asked to participate. The selected freeways carry between 80,000 and 150,000 vehicles per day. Separate counts for truck traffic indicated a range from 8000 to 17,500 trucks per day. At a total of 13 schools, 1498 children were asked to participate. From these children, 1068 usable questionnaires were obtained. Chronic respiratory symptoms reported in the questionnaire were analyzed with logistic regression. Distance from the freeway and (truck) traffic intensity were used as exposure variables. Cough, wheeze, runny nose, and doctor-diagnosed asthma were significantly more often reported for children living within 100 m from the freeway. Truck traffic intensity and the concentration of black smoke measured in schools were found to be significantly associated with chronic respiratory symptoms. These relationships were more pronounced in girls than in boys.
Air Pollutants↗
Air pollution from truck traffic and lung function in children living near motorways.
The contribution of motorized traffic to air pollution is widely recognized, but relatively few studies have looked at the respiratory health status of subjects living near busy roads. We studied children in six areas located near major motorways in the Netherlands. We measured lung function in the children, and we assessed their exposure to traffic-related air pollution using separate traffic counts for automobiles and trucks. We also measured air pollution in the children's schools. Lung function was associated with truck traffic density but had a lesser association with automobile traffic density. The association was stronger in children living closest (< 300 m) to the motorways. Lung function was also associated with the concentration of black smoke, measured inside the schools, as a proxy for diesel exhaust particles. The associations were stronger in girls than in boys. The results indicate that exposure to traffic-related air pollution, in particular diesel exhaust particles, may lead to reduced lung function in children living near major motorways.
Child↗
Childhood exposure to PM10: relation between personal, classroom, and outdoor concentrations.
OBJECTIVES: To investigate the validity of outdoor concentrations of particulate matter < 10 microns diameter (PM10) as a measure of exposure in time series studies, and to study the extent to which differences between personal and outdoor PM10 concentrations can be explained. METHODS: Four to eight repeated measurements of personal and outdoor PM10 concentrations were conducted for 45 children, aged 10-12 years, from four schools in Wageningen and Amsterdam, The Netherlands. Repeated PM10 measurements in the classrooms were conducted in three of the schools. Averaging time was 24 hours for the personal and outdoor measurements, and eight hours (daytime) and 24 hours for the classroom measurements. For each child separately, personal exposures were related to outdoor concentrations in a regression analysis. The distribution of the individual correlation and regression coefficients was investigated. Information about factors that might influence personal exposures was obtained by questionnaire. RESULTS: Median Pearson's correlations between personal and outdoor concentrations were 0.63 for children with parents who did not smoke and 0.59 for children with parents who smoked. For children with parents who did not smoke, excluding days with exposure to environmental tobacco smoke (ETS) improved the correlation to a median R of 0.73. The mean personal PM10 concentration was 105 micrograms/m3; on average 67 micrograms/m3 higher than the corresponding outdoor concentrations. The main part of this difference could be attributed to exposure to ETS, to high PM10 concentrations in the classrooms, and to (indoor) physical activity. CONCLUSIONS: The results show a reasonably high correlation between repeated personal and outdoor PM10 measurements within children, providing support for the use of fixed site measurements as a measure of exposure to PM10 in epidemiological time series studies. The large differences between personal and outdoor PM10 concentrations probably result from a child's proximity to particle generating sources and particles resuspended by personal activities.
Air Pollutants↗
Characterization of exposure in odour annoyance situations.
Explore the source record for details and available documents.
Air Pollutants↗
Personal exposure to fine particles in children correlates closely with ambient fine particles.
To investigate the validity of ambient fine-particle concentrations as a measure of exposure in epidemiological time-series studies, we established the association between personal and ambient concentrations, within subjects, over time. We conducted repeated measurements of personal and ambient fine-particle concentrations in 13 children who lived in Wageningen, The Netherlands. For each child separately, we related personal exposures to ambient concentrations in a regression analysis. The median Pearson's correlation coefficient was 0.86. Personal fine-particle concentrations were also highly correlated with ambient particulate matter (i.e., < or = 10-microm) concentrations (median Pearson's correlation coefficient = .75). Personal fine-particle concentrations were typically approximately 11 microg/m3 higher than ambient concentrations. We excluded measurements of children who were exposed to environmental tobacco smoke, and the difference was only 5 microg/m3. The findings of high correlations between personal fine-particle concentrations and both ambient fine-particle concentrations and particulate matter (i.e., < or = 10-microm) found in this group of children provide support for investigators to use ambient particulate matter concentrations to measure exposure to fine-particle concentrations in epidemiological time-series studies.
Air Pollutants↗
Personal sampling of airborne particles: method performance and data quality.
A study of personal exposure to respirable particles (PM10) and fine particles (FP) was conducted in groups of 50-70 year-old adults and primary school children in the Netherlands. Four to eight personal measurements per subject were conducted, on weekdays only. Averaging time was 24 hours. Method performance was evaluated regarding compliance, flow, weighing procedure, field blanks and co-located operation of the personal samplers with stationary methods. Furthermore, the possibility that subjects change their behavior due to the wearing of personal sampling equipment was studied by comparing time activity on days of personal sampling with time activity other weekdays. Compliance was high; 95% of the subjects who agreed to continue participating after the first measurement, successfully completed the study, and, expect for the first two days of FP sampling, over 90% of all personal measurements were successful. All pre and post sampling flow readings were within 10% of the required flow rate of 4 L/min. For PM10 precision of the gravimetric analyses was 2.8 microgram/m3 and 0.7 micrograms/m3 for filters weighted on an analytical and a micro-balance respectively. The detection limit was 10.8 micrograms/m3 and 8.6 micrograms/m3 respectively. For FP, weighing precision was 0.4 micrograms/m3 and the detection limit was 5.3 micrograms/m3. All measurements were above the detection limit. Co-located operation of the personal sampler with stationary samplers gave highly correlated concentration (R > 0.90). Outdoor PM10 concentrations measured with the personal sampler were on average 4% higher compared to a Sierra Anderson (SA) inlet and 9% higher compared to a PM10 Harvard Impactor (HI). With the FP cyclone 6% higher classroom concentrations were measured compared to a PM2.5 HI. Adults spent significantly less time outdoor (0.5 hour) and more time at home (0.9 hour) on days of personal sampling compared to other weekdays. For children no significant differences in time activity were found.
Activities of Daily Living↗