Smog Period Research Articles

Health effects during a smog episode in West Germany in 1985.

In January 1985 a smog period occurred for 5 days in parts of West Germany, including the Rhur District. Mortality (24,000 death certificates), morbidity in hospitals (13,000 hospital admissions, 5400 outpatients, 1500 ambulance transports) and consultations in doctors' offices (1,250,000 contacts) were studied for a 6-week period including the smog episode and a time interval before and thereafter. The study region was the State of North Rhine-Westfalia (16 million inhabitants), but the analysis is restricted to the comparison of the polluted area and a control area (6 million inhabitants each). During the smog period, mortality and morbidity in hospitals increased in the polluted area, but there was no substantial increase in the control area. The increases were for the total number of deaths 8 vs. 2% (polluted area vs. control area), for hospital admissions 15 vs. 3%, for outpatients 12 vs. 5% and for deliveries by ambulance to hospitals 28% in the polluted area (not investigated in the control area). The effects were more pronounced for cardiovascular diseases than for respiratory diseases. The consultations in doctors' offices show a slight decrease (-2 vs. -4%). Regression analysis shows a moderate influence of temperature, but a strong influence of ambient air pollution. The maxima of the ambient concentrations are more important on the same day, whereas the influence of the daily averages is more pronounced after a delay of 2 days. The results are discussed considering other possible confounders such as indoor pollution and psychogenic influences of the alarm situation. In total, the study suggests moderate health effects due to increased air pollution during the smog episode.

Health Effects during a Smog Episode in West Germany in 1985

In January 1985 a smog period occurred for 5 days in parts of West Germany, including the Rhur District. Mortality (24,000 death certificates), morbidity in hospitals (13,000 hospital admissions, 5400 outpatients, 1500 ambulance transports) and consultations in doctors' offices (1,250,000 contacts) were studied for a 6-week period including the smog episode and a time interval before and thereafter. The study region was the State of North Rhine-Westfalia (16 million inhabitants), but the analysis is restricted to the comparison of the polluted area and a control area (6 million inhabitants each). During the smog period, mortality and morbidity in hospitals increased in the polluted area, but there was no substantial increase in the control area. The increases were for the total number of deaths 8 vs. 2% (polluted area vs. control area), for hospital admissions 15 vs. 3%, for outpatients 12 vs. 5% and for deliveries by ambulance to hospitals 28% in the polluted area (not investigated in the control area). The effects were more pronounced for cardiovascular diseases than for respiratory diseases. The consultations in doctors' offices show a slight decrease (-2 vs. -4%). Regression analysis shows a moderate influence of temperature, but a strong influence of ambient air pollution. The maxima of the ambient concentrations are more important on the same day, whereas the influence of the daily averages is more pronounced after a delay of 2 days. The results are discussed considering other possible confounders such as indoor pollution and psychogenic influences of the alarm situation. In total, the study suggests moderate health effects due to increased air pollution during the smog episode.

Organic acids in different size classes of atmospheric particulate material

During fall and winter 1986/87, aerosol samples were collected with a 5-stage impactor in an urban, a suburban, and a rural area in Central Europe. The weak acid content of aerosol particles was characterized by buffer capacity titrations, and organic acids were determined by HPLC. C 4 -C 6 dicarboxylic acids were found to be the main constituents of aerosol organic acids, with the highest concentrations occurring during a winter-time smog period. Size distributions of single species showed a maximum in the accumulation mode, indicating that these compounds have gaseous precursors. It is suggested that these precursors are of anthropogenic origin. DOI: 10.1111/j.1600-0889.1988.tb00108.x

Persistence of Peak Flow Decrement in Children Following Ozone Exposures Exceeding the National Ambient Air Quality Standard

A linear regression was calculated between the peak one-hour ozone concentration for a given day and forced vital capacity (FVC), forced expiratory volume in one second (FEV), and peak expiratory flow rate (PEFR) as determined the same day from spirograms for each of the 39 children tested on six or more days. All mean slopes were negative, except for FVC in boys, indicating a general tendency for decreased function with increasing ozone concentration. In another analysis, a summary weighted correlation coefficient between peak ozone level and each pulmonary function parameter was calculated for each of 49 children seen on four or more days. As in the regression analysis, decrements in PEFR were significantly correlated with the ozone exposure. Analysis of residuals from the regression lines provide evidence for responses of greater potential significance to the future health of the children. They indicate a different kind of response, i.e., a persistent decrement in function lasting for as much as a week after the end of a smog period of about four days' duration. The persistent effects associated with ozone could have been due to acidic sulfates as well as, or in addition to, ozone. 10 references, 2 figures, 2 tables.

The Berlin smog project—Description and summary of results

The composition of ambient air pollution, emphasising the ambient particulate matter, has been investigated for 14 wintertime smog periods (SO 2 and/or suspended particulate concentrations exceeding 400 μg m −3) in Berlin (West). The total aerosol mass concentration, the SO 2, CO, NO and NO 2 and pertinent meteorological parameters were measured. For chemical characterization the aerosol was collected by hi-volume, low-volume samplers and cascade impactors. The samples were analysed for the metals Pb, Cd, Mn, Ni; the water soluble ions: NH 4 +, SO 4 2−, NO 3 −; and the PAH's: Fl, Py, Per, BaP, BghiP and Cor. The aerosol size distribution (0,01 < d p < 20 μm) was measured by a combination of electrical and optical analysers with a time resolution of 10 min. The smog periods lasted from 6 to 100 h and occured during anticyclonic conditions with restricted vertical mixing and low to moderate wind velocities. The smog producing pollutants originated either in the city of Berlin or in the industrial regions 100–200 km away. Ambient air quality standards were exceeded by SO 2 (highest 24-h concentration: 760 μg m −3), NO x (320), TSP (930) and SO 4 2− (190). BaP levels of up to 92 μg m −3 were measured. The total sulfate level increases with the SO 2 concentration and exceeds 100 μg m −3 for SO 2 levels above 600 μg m −3. In 40% of all cases the aerosol sulfate seems to be more acidic than (NH 4)HSO 4. The secondary aerosol fraction, i.e. the sum of SO 4 2−, NH 4 + and NO 2 − ranges from 23 up to 65% of TSP and is related to the age of the pollutants. The composition of the pollutants reflects the different emission patterns of the various source regions and chemical conversions during the trip from the sources to the measuring station. Therefore, the patterns of the composition of the pollutants provide a means to apportion the pollutants among contributing source regions. Thus, it seems possible to develop a scheme to determine during an ongoing smog condition the major contributing source region on the basis of real time measurements of selected physical and chemical parameters of ambient pollutants.

Induction of ‘sister-chromatid exchanges’ in human lymphocytes in vitro by extracts of airborne particulate matter: comparison of samples from a highly industrialized area followed up for several years

In January 1985 an extended smog episode occurred in Central Europe. The Rhine-Ruhr area (Western Germany) was affected for 5 days with maximum concentrations of 0.8 mg/m3 SO2 and 0.6 mg/m3 TSP (24h averages). Health effects were investigated during the smog period and a control period before and after the smog. Daily mortality increased by 8%, hospital admissions (for respiratory and cardiovascular causes, RC) by 15%, outpatients (RC) by 12% and ambulance transports (RC) by 28%. Patients with chronic bronchitis from the Ruhr area cities showed more exacerbations during the episode, and in school children from the Netherlands lung function was reduced.In Augsburg (Southern Germany) the smog episode was less severe (maximum concentrations 0.2 mg/m3 SO2 and 0.1 mg/m3 TSP, 24 h averages). Here - by chance - the prospective MONICA study was ongoing. During the episode a significant increase of plasma viscosity, C-reactive protein and heart rate was observed in the participants.The highest ambient concentrations (maximum 24h average of 3.6 mg/m3 SO2) were measured in Erfurt (Eastern Germany). Surprisingly, no measurable increase of mortality occurred. This was explained by premature deaths during the period before the smog, were the concentrations had already been clearly above 1 mg/m3 SO2.An earlier episode took place in December 1962 in the Rhine-Ruhr area for 5 days with maximum concentrations of 5.0 mg/m3 SO2 and 2.4 mg/m3 TSP (24 h average). Daily mortality on average increased by 19%. In 1962 and 1985 the effects were stronger in cities with pollution mainly from traffic than in areas with pollution from industrial sources.In total, between 1962 and 1987 two major and several smaller smog episodes occurred in Central Europe. Patients with cardiovascular diseases were more severely affected than patients with respiratory diseases. Health effects were more strongly correlated with TSP than with SO2.

Monitoring "Rijnmond smog" for alert conditions

The Central Environmental Protection and Management Agency Rijnmond (DCMR) has stressed the reduction of emissions during smog periods and the prevention of stench waves. For this purpose an alert system has been devised and perfected in such a way that the interests of both the populace and industry are served. The objective of issuing alerts is to bring about temporary reduction in the normal emission pattern during periods of increased air pollution so as to prevent or reduce a nuisance. Arrangements have been agreed upon between the larger plants in Rijnmond and the Report and Monitoring Center concerning voluntary measures; which are to be taken by industry in the event alerts are issued. Type of weather, wind direction, wind speed, temperatures, height of inversion layers, cloudiness, and radiation are considered before alerts are issued. Conditions needed for an effective alert system are automatic measuring equipment, short sampling times, and the availability of the measuring results results at a central control-point via direct transmission.

The aerosol size distribution of Los Angeles smog

A total of 342 atmospheric size distributions have been measured at the California Institute of Technology in Pasadena, CA during August and September 1969 over the size range 0.003–6.8 μm using the Minnesota Aerosol Analyzing System in collaboration with other investigators making chemical, meteorological, mass, and optical measurements. This paper presents characteristics of the aerosol size distributions and discusses the significance of these findings. It also presents a new computer-compatible system of nomenclature and a new system for separating and analyzing the size distribution in one decade ranges. In addition to the usual log ΔN/ ΔD p versus log D p plot, it was found that a plot of ΔV/ Δ log D p versus log D p was very useful for characterizing the distribution of particles larger than 0. 05 μm. From the later volume distribution plot, it was found that the smog aerosol was universally bimodal with the saddle point in the 1- to 2-μm size range and with the volume fraction for the individual size distributions below 1 μm being characterized with a grand correlation coefficient of 0.9719 with log normal distributions. The grand log normal distribution had a geometric mean of 0.302 μm and a geometric standard deviation of 2.25. The grand average volume below 1.05 μm was 34 μm 3/cm 3 and the volume above 1.05 μm was 24.1 μm 3/cm 3. For sizes above 1 μm, the volume distribution increases steadily up to 6.8 μm, the largest size measured by the MAAS. Comparisons with Lundgren impactor data suggest that this larger mode peaks at 7–10 μm and then drops sharply at about 15 μm. The grand average number distribution log ΔN/ ΔD p vs. log D p was very similar to the grand average measured by Clark and Whitby in Minneapolis in 1966. The number distribution can be characterized reasonably well in the size range from 0. 2 to 7 μm by ΔN/ ΔD p = 0. 4 VT D p −4, where VT = 58. 1 μm 3/cm 3, the total volume fraction. The volume fraction smaller than 1. 05 μm was found to correlate well with light scattering, solar radiation, and, to a lesser degree, with ozone. Analysis of the data and comparisons with laboratory studies of coagulating aerosols suggest strongly that, during the daytime when there is even light smog, most of the aerosol mass, in the size range smaller than 1 μm, is contributed by condensation of photochemical reaction products on particles larger than 0. 1 μm rather than from coagulation of smaller particles. There is considerable evidence that, while most of the mass of particles smaller than 1 μm is contributed by photochemical reactions during smog periods, most of the mass of particles larger than a few microns comes from other sources. While the aerosol mass of particles smaller than 1 μm peaks at about noon, the maximum in the condensation nuclei count peaked at about 1500 at values on the order of 1. 8 × 10 5/cm 3. On the other hand, in Minneapolis, when there was no volume peak at noon, the condensation nuclei count peaked at 1. 8 × 10 6/cm 3. The third paper in this series shows that, because the coagulation coefficient between 0. 01-μm particles and the 0.3-μm particles of the lower volume mode is much higher than for 0.01-μm particles with themselves, the presence of the relatively large volume below 1 μm in Los Angeles smog decreases the maximum condensation nuclei count observed compared to cities with less severe air pollution.

Ultrastructural effects of air pollution on lung cells.

The lungs of exposed mice taken during 2- to 3-hour heavy smog periods (over 0.4 ppm total oxidants) showed various degrees of cytoplasmic damage in the alveolar epithelial cells. The extent of damage was markedly age-dependent. Alveolar wall cells taken during heavy smog from 5-month-old animals contained slightly more lamellar inclusion bodies than corresponding animals kept in clean air. The cytoplasm of alveolar cells of 9-month-old animals sacrificed during heavy smog was severely disorganized; however, animals of this age showed a marked recovery 14 hours following the smog peak. In a group of older mice (21 months), similar cytoplasmic damage was obvious, and those sacrificed 24 hours after the heavy smog peak showed even more cellular disruption, suggesting irreversible damage in the older animals. The effect of synthetic photochemical smog showed a pattern of ultrastructural alterations similar to that of the heavy natural smog. Some permanent changes occurred in alveolar cells of 15-month-old mice. Partial recovery of lining cells took place, but few wall cells and phagocytes remained. If older lung tissue has relatively fewer wall cells as is indicated, recovery is decreased to the point of permanent damage. Coupled with extensive disruption of lining membranes, exposures of this nature may well cause the death of older animals.