Air Quality and Stationary Source Emission Control (1975) / Chapter Skim
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4 Health Effects of Sulfur Oxides
4 Health Effects of Sulfur Oxides
Pages 58-169
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From page 58... ...
furthermore, children appear to be at greater risk than healthy adults, owing presumably to their greater degree of mouth-breathing, relatively greater tidal volumes, and higher frequency of respiratory tract infections. The effects of air pollutants in children have been reviewed by a committee of the American Academy of Pediatrics {1970, and more recently by Wehrle and Hammer 41974~.
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From page 59... ...
They observed independent and additive effects of social class, family size, history of signif icant respiratory disease, and area of residence on pulmonary function, as measured by peak expiratory f low rate. Residential area appeared to have the greatest influence on pulmonary f unction; this suggested an ef f ect of air pollution.
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From page 60... ...
' ',T;~, .' l i' , ! ., 60 I: be greatest in the this suggests an .~ nor pollution effect to lower socioeconomic Classes :, ~ ~· _ ~ _ in_ me., .j !
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From page 61... ...
Itch 1 946 E a - coal into four severity were wever, no .s observed. gradient of ras an pollution "act and before in first 2 tal years; two or more ~ 5; excess g periods of .chitis.
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From page 62... ...
I: [~ i `,.,~, 1 1 i,,',, l ~~ :." let ..,,,'.
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From page 63... ...
~ relationship may hare been obscured by the fact that not all children lived close to their schools. There were some -statistically significant differences in pulmonary function, particularly peak expiratory f low rate ~ that suggested an ef f ect of air i: :~ ..'t Is .
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From page 64... ...
Air monitoring data are not presented. A recent study by Mostardi and Leonard (1974} reported a decrease in pulmonary function in high-school students in Barberton, Ohio, an industrialized area, compared with that in Revere, Ohio, a more rural community ~ These students had initially been evaluated in 19 7 0 and were restudied in 1973.
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From page 65... ...
Furthermore, the sulfur dioxide concentration (by lead peroxide candle, 0.96 mg of sulfur trioxide per 100 cm2 per day in 1971} was much higher than that recorded in Berlin, New Hampshire, although there is an unexplained decrease to 0.36 mg/100 cma per day in 1972. The air monitoring data for Barberton show a peak yearly mean 24-hr concentration of total suspended particles of 109 ugly in 1969, which decreased to 77 ugly in 1973, and peak yearly sulfur dioxide of 1.11 mg/100 cm2 per day.
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From page 66... ...
The explanations advanced for this finding are at best tentative. There were fewer short-term than long-term residents, so these anomalous findings decreased only slightly the overall gradient in lower respiratory infection attack rate for all residents.
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From page 67... ...
In general, the data do appear to substantiate an increase in lower respiratory disease in children exposed for a f ew years to sulfur dioxide at 90- 1 00 ug~m3 and suspended sulf ates at 1 S ug~m3 in the presence of total suspended particles at concentrations below the air quality standard. No f irm conclusions can be drawn, but the findings raise the suspicion of an ef f eat of suspended sulf ates .
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From page 68... ...
. Although comparison of these two similar studies is somewhat impeded by the larger dif f erence in socioeconomic status between communities in the Rocky Mountain area, it should be noted that the relatively less polluted Salt Lake Basin area had higher adj usted attack rates -- particularly multiple attack rates -- of lower respiratory infection.
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From page 69... ...
In the years preceding the study, both New York City co~rununities had sulfur dioxide and total suspended particle concentrations well above air quality standards. However, at the time of the study, annual mean sulfur dioxide concentrations were 51-63 ug~m3, and the concentrations of total suspended particles were at or somewhat above the air quality standard of 75 ugly.
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From page 70... ...
The problems with the New York City data include the proximity of the Howard Beach community to Kennedy Airport, possible dif ferences in medical use patterns among the communities, and the lack of any trend in repeated lower respiratory tract inf ections in children, compared with those in other CHESS studies. A conservative interpretation of the New York and Chicago CHESS f amity studies would be that they tend to add further weight to the reported association of childhood lower respiratory illness with concentrations of sulf ur dioxide and total suspended particles above the current U.S.
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From page 71... ...
~ Ice lick ~ {I.
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From page 72... ...
Mean sulfur dioxide concentrations were 5 0 ugly or les s . The ma j or pal lution gradients were observed for total suspended particles, which averaged 96- 114 ug~m3 In the high-pollution areas and 77~82 ugim3 in the lowpollution areas; suspended sulfates , which averaged 8.
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From page 73... ...
These two cities are of interest, in that their sulf ur dioxide concentrations are negligible and their particle |
From page 74... ...
Therefore, it should be assumed that concentrations of sulfur dioxide or total suspended particles above the present standards will result in an increase in childhood lower respiratory tract infection. There is a distinct possibility that suspended sulfates are directly related to this effect.
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From page 75... ...
Although, from the medical point of view, the available evidence indicates that it is prudent to assume that recurrent childhood respiratory infections do play a role in the eventual development of disabling chronic respiratory disease r there is at present no absolute scientific evidence to support this assumption. BRONCHIAL ASTHMA Bronchial asthma is a disease characterized by attacks of marked hyperconstriction of the trachea and bronchi, leading to whee zing and gasping for breath.
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From page 76... ...
Furthermore, the seasonal nature of asthmatic attacks presumably reflects meteorologic factors, as well as variations in specific allergen sources. The extent to which f actors that af f ect allergen concentrations are synchronous with f actors that af f ect pollutant concentrations will have a great impact on any observed association between ,~ - ...
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From page 77... ...
77 ad.
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From page 78... ...
19741. This results in appreciable concentrations of sulfur dioxide and suspended sulfates in association with relatively low concentrations of total suspended particles, nitrates, nitrogen dioxide, and other usual urban pollutants that might tend to obscure the effect of sulfur oxides.
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From page 79... ...
In this analysis, a signif icant statistical association of suspended sulf ates with asthma attacks was observed only in the high-pollution community; the lowpollution community had a negative association of asthma attack rates with suspended sulf ates at all temperatures. Multip, e regression analysis, which evaluated the effect of air pollutants after first considering that of minimum temperature, again showed a highly significant statistical association of sulf ates with daily asthma attack rates in the highpollution community.
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From page 80... ...
A~13 percent increase was noted for total suspended particles at 76-260 ugym3 con days when the minimum temperature was 3 0- S O F In the same temperature range for suspended sulfates, there was a 9 percent increase at 8.
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From page 81... ...
3 ugly for minimal temperature of less than 30 F The threshold for total suspended particles was estimated at 56 ugly when minimum daily temperature was 30-50 F; it was further calculated that, at 260 ug~m3, the 24-hr standard, there would be a 22 percent increase in asthma attack rate.
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From page 82... ...
Temperature was strongly and negatively associated with attack rates. Af ter multivariate adjustment for the effect of temperature, all the pollutants measured -- including total suspended particles, sulf ur dioxide, suspended sulfates, and suspended nitrates -- were also significantly correlated with asthma attack rate.
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From page 83... ...
The study used the data of Winkelstein et al. {1 9671, who, on the basis of monitoring for 1961-1 963, had previously divided Erie County into four areas of annual mean concentration of total suspended particles; less than 80, 8 0- 1 00, 100-135, and more than 135 ugly.
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From page 84... ...
People with childhood eczema tend to develop allergic respiratory disease, but this would not account f or their hospitalization with a skin condition. One possible conclusion is that this study illustrates a potential pitf all in epidemiologic studies of allergic asthma: that meteorologic conditions conducive to a distribution of pollutants in a given area may also predispose to a similar distribution of allergenic organic material.
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From page 85... ...
The tabulated data show a 50-90 percent increase in asthma emergency-room visits in the group under 13 years old on the 12 highpollution days, when sulfur dioxide concentrations averaged 0~108 ppm. Mean daily sulf ur dioxide in Harlem was similar to or slightly higher than that in Brooklyn.
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From page 86... ...
{1969} ~ although there was a slight tendency toward heightened morbidity on the day after increased sulfur dioxide concentrations. Meteorologic data are not presented.
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From page 87... ...
Taken as a whole, the studies described here suggest that sulfur oxides Indoor particles potentiate asthma attacks in susceptible people. Such effects might be reasonably expected to occur at pollutant concentrations somewhat above the present air quality standards in con junction with specific meteorologic factors.
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From page 88... ...
88 it..
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From page 89... ...
as Icy, as e c of it.
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From page 90... ...
A discussion of the effects of air pollution in chronic respiratory disease would be incomplete without mention of two major determinants of lung function: cigarette-smoking and aging. Cigarette consumption has been clearly and consistently related to a loss of lung function and to a prevalence of chronic respiratory disease.
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From page 91... ...
" Studies of mortality depend heavily on the accurate filing of death certificates. Onfortunately, this is not a highly reliable source of data, particularly if it is used to sample the total amount and types of respiratory disease mortality in a given area.
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From page 92... ...
During this period, death rates for influenza and pneumonia combined were relatively stable; they are currently about double the death rate for chronic respiratory disease. The causal relation of severe air pollution episc~aes~to increased mortality is firmly distal fished {Glasser and Greenburg 1971, Greenburg et al.
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From page 93... ...
However, the variable nature of mortality data does not permit the determination of whether luff e span is shortened only in relatively unhealthy people, who will then die in the days and weeks- after exposure' or in a much larger segment of the population. An extensive literature concerning the association of air pollution with respiratory disease mortality in Great Britain is available.
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From page 94... ...
He also noted that the rural bronchitis mortality was 46~1-00,000, which implies that rain acidity is not the only factor involved. A smaller, but still significant, correlation of bronchitis mortality with winter sulfation rate {a measure of sulfur dioxide} was also observed.
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From page 95... ...
Both smoke and sulfur dioxide concentrations correlated with deaths due to respiratory disease, and the effects were most apparent at lower temperatures. One relatively unusual finding among British investigators was a better correlation with sulfur dioxide than with smoke.
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From page 96... ...
The cutof f point for the highpol lution area, selected to be one standard deviation above the mean for the entire city, was based on a geometric mean sulfur dioxide concentration of 0. 0 13 ppm and a sulfation rate of O .
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From page 98... ...
This is a crucial point, particularly because, without such further statistical analysis, it is difficult to obtain precise dose-response information or to assess minimal no-effect concentrations. Evaluation of the Erie County mortality data in relation to sulfation rates did not reveal any association, nor was there any evidence of a synergistic effect with total suspended particles.
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From page 99... ...
Adjo ~ W f°e W~ W W ~-9 and sulfur diox de to smoke shade (COHS} Y rk CitY ronitoring station. $emp When deviation fr deviat-ions ~ d fly sulfur dioxide concentratdiofnOr,tahe days ~e-t j~_s,It,,: lower concentrations, and a sharp increase ~n it wa present on Y on the mostt d xcess morta y were uncor fluted days.
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From page 100... ...
3 ppm, although a gradual increase }'Blow this concentration was also observed. This study tends to support an association of deaths in New York City with daily sulfur dioxide concentrations higher than permitted (U.S.
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From page 101... ...
lo' ~ :~ it; ; ad to ~ .,..~....
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From page 102... ...
Although the results are in the same direction, the fact that they vary widely in magnitude indicates further the difficulty in determining precisely what degree of air pollution produces how much illness in how many people. Both Buechley and Sch~mmel are extending their observations to more recent years, in which sulfur dioxide concentrations have been greatly reduced.
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From page 103... ...
In.addition, as discussed earlier, some variables, such as; meteorologic factors, are related to pollutant concen -- tration. and have independent effects on respiratory disease.
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From page 104... ...
Although Me increased prevalence of chronic respiratory disease in urban adults is conceivably due in part to the population density and greater mobility -- leading to a higher incidence of endemic and epidemic respiratory tract infections, compared with that in more isolated rural areas -- this would not explain the ma jor dif ferences observed. Furthermore, comparisons of cities with similar population densities but different degrees of air pollution have tended to confirm an association of air pollution with chronic respiratory disease.
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From page 105... ...
loB Is En 1and and the 8ignifiCaA~d be,, Holland et Correlation ° P°Stical a a p°Sitit~heat approachedctsinfectiOn in we; alt.h°tDe9d with ., .,;.
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From page 106... ...
For women, the trends were smaller and less consistent, in keeping with the sma ller urban-rural differences for chronic bronchitis mortality and morbidity in women. The data as a whole further support the dominant influence of cigarette-smoking, compared with air pollution, ~> on respiratory disease.
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From page 108... ...
This could indicate the possibility of a geographically related difference in respiratory morbidity associated with sulfur dioxide concentrations below the current U.S. standard.
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From page 109... ...
However, the mean 24-hr total suspended particles were 18 0 ugly or ~ as indicated by the authors , perhaps somewhat higher. This study demonstrated that cigarette-smoking and aging were the major determinants of chronic respiratory disease prevalence and of pulmonary function.
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From page 110... ...
, in a series of studies of chronic respiratory disease in Hagerstown, Maryland, has evaluated the ef f ects of past urban residence on the peak expiratory f low rate and forced expiratory volume { 1 see} of over 40 0 white nonsmoking men 35-64 years old. None of these men had lived in Hagerstown during the preceding 2 0 years or more.
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From page 111... ...
Interconununity cliff erences in the prevalence ) ~ of respiratory disease have also been assessed ': as part of the CHESS program (Goldberg et al.
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From page 112... ...
possible biases involved in self-administered belie questionnaires, the studies taken together do ~ slight <~ tend to support an effect of air pollution on conce ;''jf chronic bronchitis prevalence rates. In ¢t for r addition, it should be noted that the subjects ~ air of these studies do not represent a particularly ~ the ~ 4~?
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From page 113... ...
After day of the week was taken into account, various pollutants, including sulfur dioxide and ozone, were found to correlate with hospital admission for diseases thought to be related to air pollution. Comparison of the one-third of the days with highest sulfur dioxide concentrations with the one-third of the days with lowest sulf ur dioxide concentrations showed that the f ormer had 13 percent more admissions for infectious disease, 10 percent more f or bronchities, and 1 0 percent more for acute upper respiratory infections.
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From page 114... ...
With respect to extrapolation of the findings, it should be emphasized that these workmen represented less than ~ O percent of the total work force and that these data are for only one winter of six. Another approach to evaluating the effects of pollution on chronic respiratory disease is · [ 1 it: \ to col stu che ~ .
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From page 115... ...
When these were tabulated for individual winter months and correlated with monthly pollutant concentrations ~ statistically signif icant associations were observed with both , 4B-255 0 - 75 - 11
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From page 116... ...
The authors identified 87 people who in 1 9 64- 1 9 6 5 were the most sensitive to changes in the degree of pollution, and 50 of these presumably susceptible people were restudied in 1 9 67- 1 9 6 8, by which time mean winter smoke concentration had decreased to 6 8 ugly and mean winter sulfur dioxide concentration was somewhat lower, at 20 4 ug~m3 . The correlations of mean symptom scores for this group of sub jects in 1964-1965 were 0.39 with smoke and with sulfur dioxide; in 1967-1968, the correlation with smoke was 0.
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From page 117... ...
~7 i ep~odes The. posseshtilhays simila~ 1~^adaptatio~ tha^,th,,,41 a,~Ove.
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From page 118... ...
Two studies in Chicago have evaluated the symptoms of patients with chronic respiratory disease with refernce to daily environmental factors. Burrows et al.
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From page 119... ...
The data indicate that, f or Ah g this of patients' low temperature is the d · s group environmental f actor in the severity °nl~nant respiratory disease during a Chicago w n hernia ~ ew of the high positive cc~rrelation `~i it. In sulfur dioxide for the ent' re yea=, O ~ whether an air pollution ef f ect wouldn't wonders observed in a detailed analyst s drain ate been of milder weather.
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From page 120... ...
The analysis of Carnow et al. {1969} appears to be more likely to detect an effect of air pollution on the morbidity of ~ patients with respiratory disease, in that the population was subdivided, allowing detection of a particularly susceptible group, and the sulfur dioxide concentrations were evaluated in relation to an extensive monitoring network, rather than an individual station.
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From page 121... ...
It is possible that increases in sulfur dioxide in the fall are associated with more respiratory tract eff ects than similar increases occuring in the winter or early spring. This is suggested by the sutdies of Lawther at al.
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From page 122... ...
Unfortunately, the questionnaire had not been designed for the study of respiratory disease, and there was poor reproducibility of results when a small subsample was retested. With the Same air pollution districts as in the Erie County study described before, it was found that cough and phlegm in nonsmokers over 45 years-old correlated with particle concentration, although the results were not statistically significant.
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From page 123... ...
I: ; have the strongest e additions hist the study appear ~edthien ,14 al,..
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From page 124... ...
Respiratory Tract Infections Inf ections of the respiratory tract are among the most common diseases in man,
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From page 125... ...
It should be stressed that the division between upper and lower respiratory tract infections and between viral and bacterial agents is somewhat arbitrary, particularly inasmuch as lower respiratory bacterial infection is often a sequelae of acute viral upper respiratory infections. Many of the studies that have evaluated the daily well-being of people with chronic respiratory disease in relation to pollutant concentrations can be considered to have indirectly assessed respiratory tract infections, in that these play a major role in the progression of chronic bronchitis.
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From page 126... ...
air quality standards are associated with an increased incidence of lower respiratory tract infection, particularly croup and bronchitis, in children. The findings have also suggested a possible role for atmospheric suspended sulfates.
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From page 127... ...
In another study of mice, Giddens and Fairchild noted that inhalation of sulfur dioxide at 10 ppm f or 24-72 hr had much greater pathologic eff ects on the nasal mucosa of mice with mild upper respiratory tract disease than on those of a disease-free group (Giddens 1972)
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From page 128... ...
A study by Goldring {19671 in which hamsters were repetitively exposed to sulfur dioxide at 650 ppm showed no additive effect of influenza virus. There was, in fact, i: Ha d]
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From page 129... ...
As pointed out by the author, the mechanism of this effect is puzzling. Further studies are-indicated before these results can be extrapolated to humans breathing ambient polluted air,-particularly because infectious disease has not been noted as a problem in hum ~s occupationally exposed to the sulfur dioxide concentrations studied or to higher concentrations.
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From page 131... ...
Total suspended particles, particulate sulfate, and soiling index were measured. Morbidity, defined - as incidence and prevalence of respiratory disease, was associated with weather factors and with "llutante.
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From page 132... ...
~ 11 _11 ~ Ill _~1 ' in!
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From page 133... ...
However, in the absence of chronic respiratory disease or an obvious, atmospheric irritant, cough is usually ascribed to acute respiratory infections. I'oudon et al.
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From page 134... ...
In both areas, an increased incidence of lower respiratory tract infection was obseved in mothers and fathers living in the more polluted communities. In Chicago, there was a slight tendency toward an association of upper respiratory tract infection with pollution, but the opposite was observed in New York.
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From page 135... ...
A role of suspended particulates in the production of lower respiratory tract illness is strongly suggested, but not proved. This association with suspended sulfates clearly deserves further evaluatzon,;wh~ch may result in the establishment of an air carnality standard more directly related to protecting the public against pollutant-induced lower respiratory tract infection.
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From page 136... ...
For the most part, it is based on the generally observed~higher lung cancer incidence in urban than in rural areas, which appears-to be unrelated to cigarette-emoking. This urban effect is still open to question, as is its relation to sulfur oxides.
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From page 137... ...
, which evaluated the relation of cancer rates within the same urban area to cliff Brent degrees of sex pollution, have found some association of sulfur dioxide or total suspended particles with some nonpulmonary tumors ~ but none with cancer of the lung, which would be the presumed site of action of inhaled sulfur oxide irritants. Lee and Fraumeni demonstrated a greatly increased risk of lung cancer in smelter workers exposed to arsenic in the presence of relatively high concentrations of sulfur dioxide (Lee and Fraumeni 1969)
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From page 138... ...
Despite the biochemical and animal inhalation :studies cited, there appears to be insufficient epidemiologic evidence to assign a def init;e risk to the possibility that ambient sulfur oxides are a factor in the production of human lung cancer. Quantitation There have been a number of attempts to quantify the damage caused by air Pollutants.
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From page 139... ...
The difficulties with this concept have been ably discussed by different authors in the recent National Academy of Sciences report on "Air Quality :and Automobile Emission CC ntrola {NAS 1974} . The last paragraph of the statement prepared by Palmes for the NAS-NRC Committee on Sulfur oxides is as follows: It should be recognized at the outset that there is no value other than zero that will carry with it assurance of absolute safety, or zero risk.
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From page 141... ...
Their major objections to the higher figures are that these are based on overestimates of the contribution of air pollution to urban respiratory disease and that there has been a misinterpretation of the Late and Seskin data to which the additional costs have been added. The first point is discussed below and seems to constitute a valid ob jection.
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From page 142... ...
S percent increase in outpatient medical costs per contact with the medical system f or respiratory disease. The Ford Energy Policy Pro ject has also evaluated the health costs of stationary fossilfuel combustion, but its model is concerned mostly with factors not related to community air pollution.
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From page 143... ...
It must be emphasized that it is inappropriate merely to balance~the health dollar costs with the price of air pollution control. There is an increment above the economic C08t~ Mate each-person aid be w~ll~g to pay to avoid being ill.
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From page 144... ...
The most apparent effect of sulfur oxide air pollutants is on increasing the morbidity and mortality associated with chronic respiratory disease, particularly chronic bronchitis and emphysema. one approach to assessing the dollar costs for this effect is to estimate the fraction due to air pollution nationwide.
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From page 145... ...
However, assuming that 20 percent of chronic respiratory disease is due to air pollution nationwide is inappropriate,-in that not everyone is a cigarette-ss~oker and son ~ fraction of the-probleo~ is related to constitutional factors and occupational exposure.. An even greater dilution will occur when a factor isadded for the fractio*
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From page 146... ...
146 1 9 c ~ donator .' inf ections and i of i to current bute tO sulfur oxides appears reasonable the acute morbidity effect, ate to se on id seemShapperfofperGi of Sulfur °xidesofnaatniassoc;;tion Is. one polluti ~ acted respiratory traCtfinfielC oh flus would expect to ~ ~ one Tic risks ~ who ·~e ~;~ riosug accoun is net condUciOm the sUg~ reasonable estimate fr .
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From page 147... ...
Separate estimation of mortality due to air pollution is difficult inasmuch as this is due mainly to chronic respiratory disease, which has already been considered. However, one can use ibe Buachley data {Buachiey et al.
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From page 148... ...
The use of suspended sulfates as the basis for an analysis of control strategies has the advantage of indicating the importance of the atmospheric oxidation of sulfur dioxide. - never, because ~ relative potencies of the various sulfur oxides in polluted air have not been ascertained, it might be preferable to relate health effects to units of sulfur emitted into the atmosphere.
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From page 149... ...
1bg a Are delta basis for Ratifying a~s~edc Elf Age ~1 1 1 ill l !
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From page 150... ...
Bodurian (19667. Immunological changes in animal s exposed to low sulfur dioxide concentrations.
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From page 151... ...
Air pollution and peak flow rates of schoolchildren.
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From page 152... ...
Air pollution and obstructive respiratory disease in children.
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From page 153... ...
Reid ( 197 3} . Respiratory disease in young adults: Inf luence of early childhood lower respiratory tract illness, social class, air pollution, and smoking.
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From page 154... ...
The prevalence of chronic respiratory disease in a Hew Ilampshire town.
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From page 155... ...
Frequency of acute lower respiratory disease in Children: Betrospective survey of five Rocky Mountain communities, 1967-1 97Q, pp.
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From page 156... ...
1879. current Research in Chronic Respiratory Disease.
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From page 157... ...
T Combined with viral- respiratory disease.
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From page 158... ...
Hayes ~ 1 97 2} . Air Pollution and Chi ldhood Lower Respiratory Disease: Exposure to Sulfur Oxides and Particulate Matter in New York.
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From page 159... ...
. respiratory disease symptoms in adults: 1970 survey of five Rocky Mountain communities, pp.
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From page 160... ...
Arch. 160 onset of chronic respiratory disease.
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From page 161... ...
Part II . Peak expiratory f low values.
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From page 162... ...
ED Ramsey (1974~. Prospective surveys of Acute respiratory disease in volunteer families.
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From page 163... ...
Frequency of acute lower respiratory disease in children: . Retrospective survey of 48-255 O- 75 - 14
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From page 164... ...
Salt Lake asin com 1967-197°' PP. 2-55 to 2-73 In U~pe9 arch and s of gS711fUEpA_ AS.
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From page 165... ...
165 I' 165-173. AlteratiOna of lung efeAnrch RylaDd r, R
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From page 166... ...
(1971} Chronic respiratory disease among nonsmokers in Hagerstown, Maryland.
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From page 167... ...
Health consequences of Sulfur Oxides: A Report from CHESS, 1970~1971.
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From page 168... ...
(1970) Utility or futility of ordinary mortality statistics in the study of air pollution effects, pp.
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From page 169... ...
Landau (1967} The Nashville air pollution study.
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