PB82-247172
The University of Akron Study on Air
Pollution and Human Health Effects I
Methodology, Baseline Data, and Aeroraetries
Akron Univ., OK
Prepared for
Health Effepts Research Lab.
Research Triangle Park, NC
1981
I
U.S. Department of Commerce
National Technical Information Service
WTSS
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TECHNICAL REPORT DATA
(Please tail lnsuuci:ew on the ret/en* before completing)
i. REPORT NO.
EPA-600/J-32-019
2.
JOURNAL ARTICLE
§4. TIT;.! ANO soanrcc
The Univ«rs1ty of Akron Study on Air Pollution and Human
Health Effects I. Methodology, Baseline Data, and
Aeromet nics
Pb82-2<»7172
k. REPORT DATE
6. PERFORMING ORGANIZATION CODE
[-7. AUTMQRIS)
| R.A. Mostardi, D.L. Ely, N.R. Woebkenberg, B. Richardson,
I M.T. Jarrett
8. PERFORMING ORGANIZATION REPORT NO.
^.PERFORMING ORGANIZATION NAME ANO AOORESS
| Deparment of Biology
1O. PROGRAM ELEMENT NO.
I
The University of Akron
Akron, Ohio 44325
C9XA1C
11. CONTRACT/GRANT NO.
Grant No: R804256
13. SPONSORING AGENCY NAME ANO AOORESS
Office of Research and Development
Health Effects Research Laboratory
US Environmental Protection Aaency
Research Triangle Park, NC 27711
13. TYPE OF REPORT ANO PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA-600/11
19. SUPPLEMENTARY NOTES
, Reference: Archives of Environmental Health, 36(5):243-249, September/October 1981
I*. ABSTRACT
' :' '- -' ;:.. ' •
IrJLfndy dej?nnined the nealth effects of ambient air pollutants "in two grade
^chool populations in Akron, Ohio. One school is adjacent to industry and has
!J?i ?? >u'S °Vu]fur dioxide (S0?) and moderate levels of nitrogen dioxide (NO )
while the other school is 4 km east and unpolluted. This study was designed in 2
inL^ror^C,-^? ?Ur?uSes: j(1) £° identl'fy and monitor ambient levels of air pollutants
and ??ftn 51! • S the grade school so that the levels could be accurately assessed,
XL fh» « determine baseline pulmonary function values and questionnaire responses
Mr^t f-P e"tS lndl«ting any acute and/or chronic respiratory problem in the child
IJSSS A PerC6nt ?f the children enrolled in this study lived within 2 km of the
schools and aerometric stations,, thus providing for carefLl control in the stSdy region
17.
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Unclassified
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30. SECURITY CLASS fTliil pagel
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EPA-600/J-82-019
JOIJRNAL ARTICLE
the Unh/ersrty &f Akron Study on Air Pollution
and Human Health Effects I.
Methodology, Baseline Data, and Aerometrics
RICHARD A. MOSTARDI, Ph.D.
DANIEL L. ELY, Ph.D.
NANCY R. WOEBKENBERG. M.S.
BARRY RICHARDSON, Ph.D.
MARCIA T. /ARRETT, M.S.
Department of Biology
The University of Akron
Akron. Ohio 44325
ABSTRACT. This study determined the health effects of
ambient air pollutants in two grade school populations in
Akron, Ohio. One school is adjacent to industry and has
elevated levels of sulfur dioxide (SO2) and moderate levels
of nitrogen dioxide (NO2), while the other school is 4 km
east and unpolluted. This study was designed in this manner
for two purposes: (1) to identify and monitor ambient levels
of air pollutants in an area proximal to the grade school so
that the levels could be accurately assessed, and (2) to deter-
mine baseline pulmonary function values and questionnaire
responses from the parents indicating any acute and/or
chronic respiratory problem in the child. Ninety-five per-
cent of the children enrolled in this study lived within 2 km
of the schools and acromctric stations, thus providing for
careful control in the >tudy design.
The results of this study indicate that SO2 and NO2
levels are significantly higher in the school adjacent to in-
dustry. Although pulmonary function data were not signifi-
cantly different between schools, the frequency of question-
naire responses to acute and chronic pulmonary problems
was greater in the children at the school adjacent to in-
dustry. The data tend to indicate early pulmonary effects
of air pollution in children living adjacent to industry and
exposed to elevated levels of SO2 and NO2. We suggest that
additional longitudinal work that carefully monitors total
suspended particulars, NO2, SOZ, and health data should
be conducted to confirm these results.
MANY EPIDEMIOLOGICAL STUDIES have been con-
ducted to determine the cause and effect of air pollutants
on children. Some of these studies have reported signifi-
cant air pollutant effects,1"5 but others have not.*1' There
are numerous potential problems associated with epidem-
iologies! work in air pollution: (1) the inability to accur-
ately monitor air quality in the vicinity of the health study;
(2) the inability to dcternryne if the child has a subclinical
acute respiratory illness (ARI); and (3) determining if the
child has been exposed to some respiratory irritant during
the past 4 or 5 days. Obviously, there arc other problems
inherent in epidcmiological research, but it is felt that the
previously mentioned are among the most important
The purpose of this study was to determine the effects
of air pollution within a carefully controlled population of
childt en, and also sought to eliminate the three problems
cited above.
METHODS AND MATERIALS
Two schools were selected for study: (1) Seibcrling
elementary school which is located in East Akron and in
close proximity to several large industrial plants, and
(2) Betty Jane elementary school, located about 4 km east
of the Seibcrling school. These two schools and the assoc-
iated air pollution stations arc located in'a school district
where 95% of the students walk to,"arid live within 2 km
of the school. A topographical map outlining the two
: school districts and indicating point sources of air pollu-
tion is provided (Fig. 1).
Historically, the annual mean levels of air pollution in
Archives of Environmental Health, pgs. 243-249
September/October 1981 [Vol. 36 (No. S)|
243
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•C«lt •• ««•*
Fij. 1. Geographic locatiom of aerometric >Ullon> in Akron, Ohio
(•). Lar|« point source* of air pollution are indicated by (•).
this area have fluctuated during the past 8 yr. Nitrogen
dioxide (NO2) levels have been constant and have
approached 50 yg/rn3 since 1975. Sulfur dioxide (SOg)
levels have been as high as 104 fig/m* ia 1971 and as low-
as 29 ng/m3 in 1974, out during the past 4 yr levels have
been about 65 jig/m3. Total suspended particulates (TSP)
have declined from 133 Mg/m3 in 1968 to the current level
.of SSjig/m3.' -
Air pollution measurements. Air pollution stations were
set up in close proximity to each school. The Sciberling
Station was located across the street and about 100 m from
the school building at ground level. The Betty Jane station
was set up on the roof of the school, which was at a height
of 10 m. A third station, Goodyear, was set up at ground
level between the two schools to establish pollution disper-
sion patterns.
At each of the stations there was a hi-volr.me filter for
TSP and a liquid phase bubbler train for SO2 and NO2. The
hi-volumc flow rates for each »,ite were calibrated using a
Sierra orifice calibrated by the United States Environmental
Protection Agency Laboratories (Research Triangle Park,
NC). The units were operated daily for a 24-hr period begin-
ning and ending at 8:00 a.m. Each unit had a Sierra flow-'
controller which maintained flow at 1.13 m3/min. The fil-
ter papers were supplied and weighed by a Community
Health Assessment Monitoring Program (CHAMP) subcon-
tractor (Stewart Laboratories, Knoxvillc, TN).
The NO2 and SO2 absorption solutions were both sup-
plied and analyzed by Stewart Laboratories. The bubblers
were operated for the same 24-hr period as the hi-volume
sampler. The flow rate through the bubbler train was mea-
sured before and immediately after sampling using cali-
brated rotomctcrs. The flow rate (200 cc/min) was con-
trolled by using a critical flow orifice. Because the stability
of the reaction is temperature-dependent, the SO2 tubes
were temperature-controlled during the 24-hr sampling per-
iod. After the samples were obtained, the NO2 bottles were
refrigerated, the SO2 samples were frozen, and both were
shipped to Stewart Laboratories in refrigerated boxes.
Health dau. At the beginning of the school year an enve-
lope was sent home with each fourth- and fifth-grade child
which contained a letter of introduction and a selt-complc-
lion questionnaire to be completed by the parents. The
authors designed the questionnaire, but questions were
incorporated from questionnaires used in the Tucson Longi-
tudinal Population Study,* which were derived from the
NHLI Standard Questionnaire. All questions had been
previously validated by the Tucson group. Approximately
85% (74 males and 72 females at Sciberling and 94 males
and 59 females at Betty )anc) of the children returned the >
completed material. Pulmonary function testing (PFT) was
initiated using a Warren E. Collins 9-L recording spiromcter
(Benedict-Roth) located at both schools. Each unit was
carefully calibrated with respect to volume by using a 1-L
syringe and for paper speed (1920 mm/sec) by using a
signal marking device. Both units were similarly calibrated.
There was a medical technologist at each school to con-
duct tests. Both were thoroughly familiar with the testing
apparatus and were trained by one of the authors to
explain and administer the forced vitil rapacity (FVC)
maneuver in a standard manner. Intertechnician differ-
ences, both for administering the test ind for calculating
the various volumes and flows from the spirogram, were .
compared as. follows. Each technician administered the
test to the same person four times. These "hard-copy"
spirograms were then duplicatcd_and the volumes and
flows calculated by each technician, repeating each spiro-
gram three times. This entire procedure was repeated for
three different subjects. None of the mean values between
technicians were significantly different, nor were the
repeated measurements and calculations by the same tech-
nician. The average difference between two technicians
measuring maximal mid-expiratory flow (MMF)-the most
difficult to reproduce—was always less .than 2% of
approximately 1 L. The average difference for forced
expiratory volume (FEV,) and FVC was less than 1%.
Baseline determinations were conducted at the begin-
ning of the school year, concurrent with the completion
of the questionnaires by parents. For this initial testing,
each child was without any respiratory symptoms; if any
were present, baseline testing was delayed until the child-
was completely asymptomatic. Their height (shoes .off)
and weight were measured, followed by an explanation of
how the spiromcter worked, and what was required to
successfully perform
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Table l.-Aerometric Data from Three Stations in Akron, Ohio
TSP
*>4
NO,
so*
NO2
NOTEi
Seibcfting
Mm')
55.36* 2 .85 •
11. 96 10.50
5.1 7 10.26
77.48 i 4.90f
54.36 * 1.73t
N
106
106
106
108
111
Goodyear
Mm')
52.98 i 2.53
12.1 9 10.45
4.3810.14
23.81 * 3.01
27.49 11.65
N
111
111
111
112
114
Betty |ane
M">' )
51.701 3.14
II JO 10.66
4.21 t 0.24
21.39 i 3.22
36.90 1 2.49
N
70
70
70
62
64
Data collection began October 15. 1977 and ended May 31.1978.
•Values expressed as mean i standard error.
When the technician deemed the child had performed three
similar spirograms, the session was terminated. After seven
unsuccessful maneuvers, however, the session was termin-
ated and the data were not included in the study. The spiro-
grams were returned to the laboratory and all maneuvers
were calculated and converted to BTPS. The maneuvers with*
the largest FVC, and two others which were within 5%, were
retained. The FEV, o and MMF values that accompanied
the FVC were kept
To check the validity of this selection process, we com-
pared FEV, o and MMF values that accompanied the FVC
values with the best individual FEV,.0 and MMF that a
given child produced. This was possible because many child-
ren performed PFT many times during the school year.
When the mean values were compared, FEV, 0 and MMF
were nearly identical for each of the selection processes.
When adjusting the data, PFT data were designated as
dependent variables; age, height, and weight were the inde-
pendent variables. A stepwisc linear regression model with
forward order of inclusion examined the effects and rela-
tive contribution of variation for the three independent var-
iables. We chose the single independent variable or group of
independent variables that produced the smallest standard.
error of the estimate (SEE). '
Using these selection criteria, the appropriate coefficients
were used to adjust the baseline data according to the fol-
lowing equation: .-.'.-
pFTatf, = PFT + [0H, (HI - m) + pv, (wt - m)
*A»r (age-age) 1
The coefficients of 0 were generated using the combined
data from both schools.
During the second year of the study the methods and
procedures remained the same. Two technicians were placed
at each school to share the workload with the two new tech-
nicians being carefully trained, again by the same author.
They met all of previously described intcrtcchnician tests.
The second year questionnaires were slightly different in
that we were more interested in acute or chronic events
that had developed or had changed during the past year.
Baseline testing was conducted at the beginning of the year
and adjusted as described.
RESULTS
Air pollution levels. All acrometric data collection began
October 15,1977, and terminated May 31, 1978. This con-
stitutes the school year and for that period the mean values
are given in Table 1. From this Table it can be seen that
there was substantial data missing from the Betty jane sta-
tion. This was a result of the Ohio coal Strike of 1978, that
caused the station to shut down for several months. How-
ever, the Goodyear station, located approximately 2 km
from the Betty Jane station, was operated every day and
served as a control or comparative station for Seibcrling .
during this time. The question arises, however, whether the
data from the Goodyear station is representative of the
Betty Jane station. Therefore, it was decided to examine
"same-day" data, i.e., data reported on days when all
three stations were operating (Table 2). Although there arc
some minor differences, the statistical significance between
the levels of air pollution remains the same. The SO4 and
NOa levels-are not reported because they arc similar to
those in Table 1. . • ' :
As shown in Figures 2 and 3, NOz and SO2 levels fluc-
tuated from month to month. The suspended sulfatcs,
TSP, and nitrates are not shown because the month to
month values arc similar.
Because of the differences in the SO2 and NO2 levels
between these two schools, and their closeness in
geographic proximity, we substantiated our data with
another source. The Akron Regional Air Pollution Control
Agency (ARAPCA) has a ground-level station at East High
School (Fig. 1), which is just south of the Seibcrling station.
This system is part of the national surveillance system and
all of the analytical methods arc similar to ours. "Same-day"
data comparing ARAPCA data with our data are shown in
Table 3; there is excellent agreement between the two sys-'
terns. Because ARAPCA is nearer to the point sources, it
is not surprising that the "same-day" ARAPCA mean values
are slightly higher than those recorded at the Seiberling sta-
tion. The sample sizes arc small because of the necessity
of matching our data with data collected every sixth day.
The mean acromctric values reported at Seibcrling school
arc not excessively high, but the levels do exceed the Ohio
standard for SO2 (60 jig/m3), and are close to the national
annual average of 80 AJg/m3. These arc annual criteria val:
September/October 1981 I Vol. 36 (Wo. 5)1
245
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100'
A Sf>6*rlin«
If G0oay»ar
B«lt»
eo<
>
'60-
e
n
40- •
20- •
Ma,
Flf. 2. Monthly means during the school year for sulfur dioxide.
TOT
»• .. M«,
Fig. 3. Monthly means during the school year for nitrogen dioxide.
ues and the data reported ->nly represent 9 months, there-
fore, some discrepancy in t. ig/m*).
49.90 ± 3.28 f 47.80 ±3. 11
62.56 ±7.16* 32.10 ±7.47
S0.18±2.70t 32.56 ±3.27
Betty Jane
O'g/m'J
48.14 ±3.11 (/V=3I)
20.25 ± 4.35 (N = 26)
34.72 ± 3.09 (N = 26)
•Data from Table 1 used in calculations.
fValucs expressed as mean ± standard error.
t/><.005.
246
Archives of Environmental Health
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Conversely, SO2 is not welt«oSttoHed. The Seiberling
station is near point sources and is located in an open area
near a hilltop. Under these conditions the mixing is good,
as are the characteristics of vertical dispersion. Goodyear
and Betty Jane, however, are near large stands of trees and
are not as open as the Seiberling station, therefore, the mix-
ing is not as good. The foliage could also be a factor in the
tower SOj levels, as it is known to absorb SO2."-13
A final possible explanation for the large difference in
SO2 and NO2 values among the stations could be related
to plume direction. Although we have no vector analysis
data available, the plume could be funneled from the geo-
graphic valley-like location around the Seiberling hill, and
not be a factor in the Goodyear and Betty jane areas.
In summary, these aerometric data were collected in a
well-controlled surveillance system. Although there are
some missing data at the Betty Jane school and some
problems in station location, these data indicate the air
pollution levels that these school children were exposed
to during the course of the school year. Furthermore, the
data have been verified ty another independent surveil-
lance system.
In selecting students for study, an effort v/as made to
exclude anyone with any chronic low-level rhinitis or chest
•congestion; as well as any smokers. Also, the number of
black individuals participating in the study was two from
Table 3.— Same-Day Samples Collected at Seiberling and East High
School Aerometric Stations, October 1977-September 1978
Seiberling
Uig/m»)
TSP 74.0* 8.3* (ns)f
SO2 64.5±9.2 (ns)
NO2 46.2 ±3.9 (ns)
East High School
t**/m3) N
87.9 ±6.1 30
67.2*7.4 29
54.6 ±3.7 31
•Values expressed as mean t standard error.
fns = Not significant.
each school. Therefore, a very homogenous population was
being studied from each school based on the SES index,
racial mix,'and .the similarities in lung function and anihro-
pometric data.'"
The adjustment criteria used with these data were
adopted because although height always contributed the
most variance to a given pulmonary function variable, the
effects of weight and age frequently contributed enough
. variability to affect the SEE. Since we are attempting to
identify subtle differences in PFT, we felt it important to
Table 4.- Relative Risk Ratios* and Levels of Probability for Pediatric Questionnaire Responses In Akron, Ohio
l(#3)
Cough without
Cold
1976-1977 1.28 (ns)f
1977-1978 1.06(ns)
1 (#5)
.Chest Wheezy
and Whistling
1.37(/> = .08)
1.70(/> = .04)
•Relative risk ratio = RR Seiberling/RR Betty
fns = Not significant.
M#6)
Shortness of Breath
with Wheezing
T.23(/> = .008)
1.73 (/• = .!)
Jane.
H (#3)
Short of Breath
while Playing
1.53 (ns)
1.23 (ns)
II (#4) II (#5)
Catch Breath Catch Breath
while Walking while Playing
2-26(/> = .09) 1.69(/» = .008)
2.23 (ns) 1.20(ns)
II (#9)
Past 2 yr have
seen a Doctor
for Shortness ~
of Breath
6.21 (/>=.006)
1.67 (ns)
• ' '. • '
Table S.-Relative Risk Ratios* and Significance Levels of Syndromes in Akron, Ohio
Cough Phlegm Syndrome
(Grade U)
1976-1977 1.17 (ns)t .
1977-1978 1.16 (ns)
Shortness of Breath
(Grade 3+)
1.29 (/> = . 103)
1.40(/>=.2)
Wheeze
(Grade 2+)
2.39 (P =;.02)
1.45 (/>"=. 2")
Wheezing Dyspnea
(Grade 1+) .
2.00 (P = .02)
2.25(/> = .04)
Wheezing Dyspnea
and Dx Asthma
No data
t
•Relative riik ratios = RR Seiberling/RR Betty )anc, on the assumption that elevated SO2 and NO2 levels would have more
effect on students residing in the Seiberling school area.
fns = Not significant.
t Eight responded at Seiberling; none responded at Betty Jane.
September/October 1981 (Vol. 36 (No. 5)1
247
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Table 6 — Comparative, Adjusted Baseline PFT Data for Males and Females in Seiberling and Betty Jane Schools,
1976-1977
Height (cm)
Weight (kg)
Age (mo)
FVC (L)
FEVJO(L)
FEV10/FVC
MMF(L/sec)
Seiberling
(AT = 58)
140.83 ±0.90*
36.06 1 1.60
124,63 ±0.90
2.11 ± .03
1.72 ± .03
0.81 ± .01
1.06 ± .02
Males
Betty jane
(W=77)
141 .77 ±0.90
36.30 ± 1.10
127.07 ±1.07
2.13* .02
1.77 ± .02
0.83 ± .01
1.06 ± .01
Seiberling
(/V = 65)
142 as ± 0.90
37.52 ±1.00
125.32 ±0.90
2.01 ± .03
1.61 ± .02
0.80 ± .01
1.01 ± .01
Females: "•-'- ••• '•--=•.• —
Betty |ane
(/V = S6)
142.66 ±0.90
38.20 ± 1.30
"; 126.42 ±0.90 ..'
1.98 ± .03
, 1.63. ± .03
0.82 ± .01
0.99 ± .02
•Values expressed as mean ± standard error. ~ . ' •
Table 7.-Comparative, Adjusted Baseline Mean PFT Data for Males and Females in Seiberling and Betty Jane Schools,
1977-1978
Height (cm)
Weight (kg)
Age (mo)
FVC ID
FEV^otL)
FEV, o/FVC
MMF (L/sec)
Seiberling
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The authors wish to thank the Akron Board of Education, prin-
cipals, and teachers of each school for their outstanding coopera-
tion. The Akron Regional Air Pollution Control Agency wasted in ,
providing data for comparative purposes.
the authors wish to express appreciation to: Dawn'jjtorstcll and
Steven Stoner for computer programming; Jane league and Mere-
dith Dahlin for assisting in the schools; |ack Newmarchj^tevid
Schmidkin, and Mahoj Parek for operating and rriUnUinJnf the
aerometrlc stations.
Michael Lebowitz, Ph.D., was the consultant for this .project •
and his expert assistance was of invaluable help.
Supported by U.S.' Environmental Protection Agency grants
No. 804256-01.02.
' Submitted for publication February 16,1981; revised;
accepted for publication June 1,1981.
Requests for reprints should be addressed to: Dr. R. Mostardi,
Department of Biology, The University of Akron, Akron, OH
44325.
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249
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