Document DvgXpXoogg5Xo8Z272VZ2J9Ra
. " - Reprinted from Journal of Occupational Madidno
,.
Volume 27. No. 5. May 1985
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-A' Retrospactlye, Mortal ity;-$tudy^of
<s~;,WOrl<ers;Pri'CRhree Major lil.Sv'; f i
it*f.it'-qavviatYtsiWIwomjquer? tootledtoxiw; '!
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* Refineries ana iChemical Slants. iinn-j.j'--. .i
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- ~faitll Internal Cojngarispns b^Ceographig^S^.Q^UBatipn, and
. - Smoking History v/a m.-*
- '.' ; -
- 9rft >-
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n "f *'*
Nancy M. Hanis, Ph.D.; Leba G. Shallenberger, M.P.A.; Donna L. Donaleski, B.S.; Eugene A. Sales, MS
. ` t - *
4 ** .'*`1 ii'i'-:,
A cohort of 21,698 U.S. refinery andchemical plant
workers wasvbserved for eight years to determine if there " were interplant or other variations in causes of mortality. ~ --Plant populations in three geographic locations were com - bined to develop an -internal standard for comparing - subgroups within the total cohort. At no one geographic -or site were consistently different rates for all'major causes
ofdeath observed. The adjusted mortality rates for poten tially exposed workers were slightly greater than those for
nonexposed workers for most causes examined. Smokers incurred a higher risk of mortality from many causes of death when compared with nonsmokers, regardless of oc cupational category. After controlling for smoking, there remained a slight excess in mortality for potentially ex
posed as compared with nonexposed workers.
KAortality of cohorts of workers from three Exxon
refineries and chemical plants in the United States was
studied during the period 1970 through 1977. Compari
sons with the mortality experience of the U.S. population
have been reported separately'. This report details the re
sults of the analysis that combined the three plant site
populations into a single cohort to address the following
objectives:.
-
-
. 1.. To develop an internal standard for comparing
subgroups within the cohort.
-- -
. 2. To compare directly adjusted mortality rates among
From the Exxon Corporation. East Millstone. N.J. (Or. Hanis, Ms. Donaleski and Mr. Sales); and the Exxon Company, U.S.A.. Houston (Ms. Shallenberger).
Address correspondence to Exxon Corporation. P.O. Box 235, Met* tiers Road. East Millstone, N) 00873 (Dr. Hanis).
the three plant site populations using the internal com
parison group as the standard. j. .
3. To compare'directly adjusted mortality rates in the
total study population by (1) geographic site, (2) occupa
tional categories, and (3) smoking history. ' -
: r! ' ; : i | ! ( !
Materials and Methods
;; ;j!j '
The study design, cohort definition, and data handling
techniques were discussed in detail in our previous com
parisons with the mortality experience of the U.S. popu
lation.' Work history summaries and smoking histories were
used in the present analysis. Smoking histories have been
documented in employee medical records since the mid-
1960s, but consistency of detail varies by plant. The crude
measure of "ever-smoked" was indicated by **Y" (yes),
"N" (no), or "U" (unknown).
*:kiw--ss.s
Work histories were summarized to derive the occu
pation at which each employee had spent the largest por
tion of his/her working time. Nine occupational categories
were identified for analyses: official/manager, profes-
' sional. technician, office worker/cierkV process operator.
mechanical worker, unskilled laborer, service worker, and
laboratory tedinician/fietd professional.
'
' Comparisons used the total study population as the
standard unless otherwise specified. Occupational cate
gories based on employee records were classified into two
groups based on their potential for daily exposure to pe
- troleum, petrochemicals, and other related substances.
Mechanical workers, process operators, unskilled labor
ers, service' workers, and laboratory technician/field
professionals were categorized as "potentially exposed"
while officials/managers, professionals, technicians, and
office workers/clerks were considered to be "non
exposed." Table 1 shows the occupational categories by
job titles and by potential exposure grouping.
; Directly adjusted death rates were calculated by multi-
Journal of Occupational Medicine/Vol. 27. No. 5/May 1985
' 361
E K0 03 059
mi urnwn
raninu.* omo
- Fig. 1 -- Olreetfy adjusted mortality rates per 10,000 gerson-yaan, 1070 througk 1077, lor ill canes ol death, by occapatioa (704 employ* ees, accounting for 98 deaths, could not be classified by occupation).
oeonstb
MTtKTiAu.T uratto
u.s.
MMU, I. MUMU Mt wm Ml
Fig. 2 -- Directly adjusted mortality rates per 10,000 person-years, 1970 through 1977, tor malignant neoplasms, by occapatlon (704 em ployees, aecoenting lor 10 deaths due to malignant neoplasms, coaid not be classified by occapatlon).
plying each age*, sex-, race- and calendar year-specific death rate in the subgroup of interest (for example, smok ers) by the number of person-years in the appropriate cell in the standard population (total cohort). The resulting numbers of expected deaths were then summed over all the cells and divided by the total number of person-years in the standard population. This quotient was multiplied by 10,000 to yield the directly adjusted rates per 10,000 person-years. Rates among subgroups could then be di rectly compared because the same population distribution was used in the standardization procedure.1-1 The MantelHaenszel procedure, as implemented for life-table data with confounders, was used to test rate ratios for statistical significance.4*
Results The majority of employees were classified as mechanical
workers (33%) or process operators (2B%), followed by
362
professionals (11%). Based on occupational category, 75%
of the study population had potential for daily exposures
to petroleum, petrochemicals, or other factors in the
workplace (potentially exposed), 22% had little potential
for exposure (nonexposed), and 3% had unknown poten
tial (Table 2). V v.
;
As shown in Table 3, smoking information was available
for 70% of the study population..Fifty-one percent were
' known smokers and 19% had never smoked cigarettes.
Those occupational groups more likely to have potential
occupational exposures generally had higher proportions
of-smokers. Professionals had the. lowest percentage of
"smokers; however, they also had the highest proportion
of subjects with "unknown" smoking histories (Table 4).
Comparison of Directly Adjusted Mortality Rates Among
Cohorts at the Three Geographic Sites--Directly adjusted
rates for-selected causes of death for the three plant co
horts and for the U.S. population are shown on Table 5 if
there were five or more observed cause-specific deaths at
each of the three sites. No one geographic site cohort
showed consistently different rates for all major causes of
death.
Kidney cancer was the only cause of death whose rate
was higher than that of the U.S. population for all three
plant cohorts. Cancer mortality rates in Bayway/Bayonne
were generally higher than those in other plants, although
only slightly higher than the U.S. rates, particularly for
cancer of the digestive organs (with the exception of pan
creatic cancer) and respiratory system. The rate for cancer
of the pancreas was higher in the Baton Rouge cohort.
Comparisons by Occupational Category--Mortality rates
for potentially exposed workers were slightly greater than
those for nonexposed workers for most causes shown,
with the exception that there was a twofold greater in
crease in cancer of the prostate. For the.category of all
causes of death and for diseases of the circulatory system,
the differences between the two groups were statistically
significant. Mortality due to cancers of the brain/CNS was
elevated considerably for workers classified as non
exposed to petroleum, petrochemicals, or other factors
in the workplace. Most of the deaths from cancers of the
bladder and kidney and from lymphosarcoma/reticulosar-
coma and leukemia were in potentially exposed workers
(Table 6).
The nonexposed technicians had the highest rates for
all causes and for all malignant neoplasms (Fig. 1 and 2).
Table 7 shows the directly adjusted mortality rates for se
lected cancers by specific occupation. No one occupa
tional group had consistently higher rates than the others
for specific causes of death. Process operators had the
highest rates for cancers of the digestive organs, respira
tory system, and kidney; these rates were also higher than
those of the U.S. population. Mechanical workers had the
highest pancreatic cancer rate; this was also higher than
the U.S. rate.
.
Comparisons by Smoking History--The following com
parisons were based on smaller numbers of deaths, since
smoking data were unavailable for 30% of the cohort. Rates
were not calculated when the observed number of deaths
was less than five. Mortality rates for selected causes of
death, shown on Table 8, were compared for smokers
(ever smoked) and nonsmokers (never smoked). Smokers
Mortality Study/Hanis et al
EM003060
n*lOC|
"ii Tibli 1 -- Occapatiorul Grovp Oifliffloa -
* >
iJW *'b
TE.?
&>
'Potential Exposure
A--Offksals/managers
.-. Buyers
Chiefs Department heads
iow -\f^wnncrcf'iDMialencatgoersrs . ITT^ Superintendents
-.w'.ti i .>*1 ^*^$ypervisors
"
,c" '^ellprofessionals/nonexposed
F--Process operators;?:
Coke handlers/rollers '
v.l.
.. 1
Dock helpers/masters ; Gaugers r
'-
J" ` Plant trainees
>.
Process operators
-
; . Process technicians
'
' ' Receiving/shippingoperators
. .G--Mechanical workers '
~H=-Laborers----------------------
.. ^ ` `Wio \'.-c :c"l!
Handym#n
- Laborers A
:
Tankermen/deckhands ,
.Ublitymen..
,
...Yardmasters/cleaners. __
J--Service workers
!
Chauffeurs -aeocx.. :
Chefs/cooks
:
Accountants
- ' ` t -i; - -Auto mechanics
Rremen/Fire equipment
|eyr y,*~ no AlUlyStS
** Yin4 :oricj sfuAhomeys
ar!1 f`l ;.mv
^Coordinators
rvEditors
. c -< <: . >.Boilermakers >* .'-.SC Carpenters
; 1*,;'>rv * ..Craftsmen . Electricians
...
;c-;
Inspectors ..i'r,r!:;.-i
Guards .sonro-i-ciito ; Janitors/maids mU.... ` . Storekeepers
Engineers
Instrument men
________
. K--Laboratory Technicians/* I
; ,... - Foremen/supervisors
. Instrument technicians
____ Field Professionals_______
.... -Nurses ' ' Physicians
Planners Scientific advisors
- C--Technicians/nonexposed
Cameramen
" Chainmen
--- Computer technicians
Data technicians
Designers
.
Draftsmen
- - Engineering technicians
- Hospital/first-aid men
. Surveyors
1E--Office/derical
' ' Key-punch operators Office assistant/clerks Office machine mechanics Reproduction operators
Insulators ------ ;, .
Lead burners
' '''
Linemen
_
Machinists
Maintenance foremen
--
Maintenance/mechanical helpers
Masons
-
Materials men
Measurement men '
Mechanical asssistant/helpers
Mechanical supervisors
.Motorized equipment operators
Oilers
.
. Painters
-
Pipefitters
Plumbers '
.
Railroadmen
-
Riggers
Servicemen
Tinners
.... STenders/testers .
. Chemists
..... Gas testers---------------
Industrial hygienists *____
Laboratory assistants'
Laboratory foremen
Laboratory supervisors
-___Laboratory technicians
___Oil conservation I 'J
inspectors
Refinery equipment
''inspectors
" -"
' Research engineers
Research technicians
:
- "T Safety inspectors
' X-ray technicians-
Trainees
Transportation operators
Warehousemen
Welders/bumers
Wiremen/joumeymen
experienced a higher risk of death due to the majority of causes shown. Of these, the excess numbers of deaths due to smoking were statistically significant for all causes of death, diseases of the circulatory system, diseases of the respiratory system, diseases of the digestive system and for all malignant neoplasms. Smokers also experi enced a higher rate of digestive organ cancers, but the increase was not statistically significant. Rates for pan creatic cancer, cancers of all genitourinary organs, and prostate cancer were slightly higher for those who had never smoked. Most of the deaths from cancers of the liver, respiratory system, bladder, kidney, lymphopoietic system and from leukemia occurred in smokers, but there
Journal of Occupational Medicine/Vol. 27. No. 5/May 1985
were too few cases in the nonsmoker group to compare rates in these categories. ' ' '
Rate ratios of "ever" to "never smoked" indicated about a twofold difference between smokers and nonsmokers for most causes of death in both exposure categories. In the potentially exposed group the differences between smokers and nonsmokers were statistically significant for all causes of death, for diseases of the circulatory system, and for malignant neoplasms. In the nonexposed group the excesses for smokers were statistically significant for all causes of death and for malignant neoplasms. The ex ception was for cancer of the pancreas, for which, among `the potentially exposed workers, the rate was higher among
. 363
EM003061
Table 2 -- Distribution'of Total Study Population by Occupa tional Cateoory '.......................
Occupational Category______ T'^Nn
_
Potentially exposed Process operators Mechanical workers Laborers "" *" "
Service workers ' ' ' Laboratory technicians/field professionals-
Nonexposed
.
Officials/managers
Professionals
Technicians " -:-
Office/clerical - - -
Unknown
: '
Total
16,257
74.9
6,135
28.3
7,162
33.0
1,572
7.2
479 2.2
909 4.2
4,737
21.8
501 2.3
2,476
11.4
269 1.2
1.491
6.9
704 3.2
21,698
99.9
<*
Table 3 -- Distribution of Total Study Population by Smoking History
Ever Smoked
No.
%
Yes No Unknown Total
11,105 4,059 6,534 21,698
51.2 18.7 30.1 100.0
nonsmokers (Table 9). In this Table, comparisons cannot be made across all four exposure/smoking groups because the two different occupational subgroups, not the total population, were used as the standards. The death rates for all causes among the potentially exposed workers were only slightly higher than or about the same as those among
the nonexposed for. both smoking gcoupsJTable 10). For
smokers, the slight excesses remaining among the poten
tially exposed, compared with the nonexposed group, were
statistically significant for all causes of death.and for dis
eases of the circulatory system.
. ,~
Discussion
.
The majority of this cohort were mechanical workers or
process operators during the major portion of their em
ployment periods. Smoking histories were available for
70% of the population. Those groups more likely to have
occupational exposures generally had higher proportions
of smokers as well.
' 1
Mortality rates for digestive and respiratory cancers were
higher in the New Jersey cohort. The conspicuously high
rate of pancreatic cancer in the Louisiana cohort may ex
plain the increased pancreatic cancer risk observed in the
total study population.1 Local,-state, and county mortality
data show similar patterns of cancer excesses for these
geographic sites.' The kidney cancer rate was the only one
found to be higher than that of the U.S. population con
sistently across the three plants. However, the magnitude
of increase was small and not statistically significant. Ad
ditional analyses would be required to determine if these
(cancer rate) differences represent true geographic vari
ations or differences among plant processes. Detailed
comparisons with state and local rates might provide more
insight, and further analyses by plant processes at the three
sites may be of academic interest; however, considering
the low realtive risks observed, additional geographic analyses may not be justified.
Occupational groups were examined by comparing po
tentially exposed workers'with nonexposed workers. The
definition of occupational category was based on job titles
and not on specific processes or chemical agents at the
work sites. Misdassification may have occurred as em
ployees were assigned to an occupational category based
Table 4 -- Distribution of Occupational Categories by Smoking History, 1970 Through 1977
Occupational Categories
Ever Smoked No. %
Never Smoked No. %
Unknown No. - %
Nonexposed Officials/managers Professionals Technicians Office/clerical Subtotal
.
Potentially exposed
Process operators
Mechanical workers
Laborers
Service workers
Laboratory technicians/field
professionals
Subtotal
-
Unknown Grand Total
.
. ' ' 255 797 144 638 . 1.834
3,368 4,080
835 241
505 9,029
242 11.105
50.9 32.2 53.5 42.8 38.7
54.9 57.0 53.1 50.3
55.6 55.5 34.4 51.2
100 566
66 409 1,141
1,032 1,313
182 59
213 2,799
119 4,059
20.0 146 29.1
22.9 1,113 45.0
24.5 59 21.9
27.4 444 29.8
24.1
1,762
37.2
16.8 1,735 28.3 18.3 1,769 24.7 11.6 555 35.3 12.3 179 37.4
23.4 191 21.0 17.2 4,429 27.2 16.9 343 48.7 18.7 6,534 30.1
Total No.
. 501 2,476 269 1,491 4,737
6,135 7,162 1,572
479
909 16,257
704 21,698
364 Mortality Study/Hanis et ai
~Tab!a S--Dlrvctty Adlrated'Mottaltty Ratal per.10,000 Renos-Years tor Deaths Due to Selected (touses SISiaKSa Roege,
>l-....... -*~*`*1' "`'Baytown, ami Biyway/Biyonne Cohorts and the U.S..Popttlttioa,1970 Through 1977''
[
jemiwH____ jSaeseof deatht-
Heath Rate'
Baton Rouge
Baytown ' -Bayway/Bayonne
Ohtemd * ki; ..Observed
`Observed ..0
__ 1HO___ (tote----"-- Ho--------- Rate. --No--/.Rato
-ait* .i** Highest
Rato Rata ..JUttof
.All causes.ol death (000-999)
-1,205 238.9
784 .238.7 1-.209 .239.2..
0.91
' All malignant neoplasms (140-209) ` Ait digestive organs (150-159)
Stomach (151) Large Intestine (153) Pancreas (157) Alt respiratory system (160-163) Lung (162)
249 . 73
r 11 - 24
; 23 - 79
. 78
47.5 13.5
1<5 4.5 4.7. 15.3 15.2.
158 39
6 11 10 54 54
46.6 1.14,7
1.8 5.8 3.3 14.6 14.6
r259. '
"Xi 84/ .;i7.c
16
9 -SHfc
.84, 77" -17J.'/56^
i.ir 1.3; i.i i 1.31
1.7; 1.11 1.11
All genitourinary organs (180-189) -39 7.8-
20
4.9 41
0.9!
Kidney (189) . '
9 1.7.
6 1.2
7
1.5j
All lymphopoietic (200-209) Endocrine/nutritional/metabolic
diseases (240-279) Diseases of circulatory
- 25 18
729
4.9 3.4
147.4
16 4.0 9 7.9
455 140.6
14 ; 32,
762.
... 142.T7^.8
1.11 1.7!
r
1.0:
system (390-458) Diseases of respiratory
66 13.5
48 17.3
Z9' 50 ' 8.4
0.9.
. system (460-519)
Diseases of digestive system
__ (520-577)___
______ ... _
Diseases of genitourinary
34 6.6
_ . . __ . _......
25 .5.1
25 6.2 ...............
10 3.0
X&ZBt*''
0.8;
16 3^:: .-33S&T 1.41
system (580-629) Symptoms/senility/ill-defined
8 . 1.5
. 17 4.7
. ::: io..alfaOo#fr 17 5;H to. ,<SS2sto>?* 1.6 j
-(780-796)- --------------------All external causes (E800-E999)
52-' : 9.2*
38-
8.9'
..2t sa. -^*i.wi|4ayfv^*^ ad.*' ie
Total No. of person-yearss Total No. of employees]
56,012.0 .... 8,662
46,192.6 .7.322
35.525.8 *5,776
;aa3( 101 ; ' fltteto 4iQ3V i
total No. of deaths ' 1,205
784 "'1.209
* Rates for the three plant cohorts and the U.S. population were directly adjusted for age. sex. race, and calendar year using the total study population
as the standard population
t international Classification of Oiseases (ICOA), eighth revision codes shown in parentheses
..
...... ......
X Ratio of the highest plant mortality rate to the U.S. rate
' .......... .. '
$ The sum of person-years for the Baton Rouge, Baytown, and Bayway/Bayonne cohorts is slightly greater (27.8 person-years; or 0.02% of the total
person-years) than that for the total study population, owing to rounding
' .. -
I An employee may have been at more than one plant dunng this observation period
- .- - -r.,- r>> ..: -
....
. ...
i if)?? .
on where they had spent the largest portion of their work ing time. It is impossible to determine accurately the mag nitude of misdassification, effects of which tend to dilute any real difference.* Furthermore, the use of complete work histories for analyses requires more extensive meth odological development. The mortality rates tended to be higher among potentially exposed workers than among
- - -
i >rr.-
- '.r^l .**
be interpreted further. Other exceptions included the res
piratory and digestive system disease rates and the brain/
CNS cancer rate, which were higher for . nonexposed
workers. The brain/CNS result does not. support the re
cent finding in the Texas Gulf Coast study,, in which the
proportion of brain cancer deaths was higher than ex
pected among refinery and petrochemical workers' who
nonexposed workers but the differences were minimal. One exception was the nonexposed technicians, who had the highest rates for all causes and for all malignant neo plasms. This occupational group represented 1.2% of the total population and only 0.9% of the deaths (N=269; number of deaths, 30). Since these rates are based on a
were union members.* No one occupational subgroup had consistently higher mortality rates for all causes of death examined. However, rates were found to be generally lower for managers, professionals, and clerical workers. '*
Smokers generally had .higher mortality rates than non smokers, with the exception of deaths from cancers of the
very small number of deaths and since the list of main jobs included in this occupational group does not suggest areas with occupational exposure problems, the relatively higher rates among the nonexposed technicians cannot
pancreas, genitourinary organs, and prostate. However, these observations were based on small1 numbers and interpretations should be made with'caution. Smoking history explained most of the differences observed be-
. Journal of Occupational Medicine/Vol. 27. No. 5/May 1985
365
EM003063
Table 6--Observed Number ol Deaths and Oirectty Adjusted* Mortality Rates per 10,000 Person-Years for Selected Causes
_*- ^
- ` of Death, by Occupational Categories, 1870 through 1977'
______
________________ ...
............... Occupatlonal.Cateooryt_________
nr
. 'V"
Potentially Exposed
y.Nonesposed
; - Cause of Death**; *
Observed No. Rate Observed No. Rate
RR{
- All causer(000-999) ------------ --.------------- 2,657 "
. - All malignant neoplasms (1.40-209)
557
All digestive organs (150-159)
. 167
' Uver/gallbladder/bile ducts (155-156)
14
Pancrear(157) ,
35
All respiratory system (160-163)
. 185
Lung (162)
177
; . All genitourinary organs (180-189)
87-
Prostate (185)
50
Bladder (188)
''
-16
Kidney (189)
'
18
. Brain/CNS (191-192)
8
All Lymphopoietic (200-209)
45
Lymphosarcoma/reticulosarcoma (200)
10
Leukemia (204-207)
15 .
Oiseases of circulatory system (390-458)
1.640
Diseases of respiratory system (460-519)
124
Oiseases of digestive system (520-577)
66
Diseases of genitourinary system (580-629)
AT
- 236.149.8 14.6 i.2 : 3.o 16.7 .16.0 7.7
-.4.4 1.4
. 1.6 -0.7
4.4 0.9 1.7 145.6 10.8 5.8 4.0
Total No. of person-years
Total No. of employees Total No. of deaths
103.360.1 16,257 2,657
-------443'
. 99 - 25.
0
7 29
. 29 ` 11
5 3' .3 7 9 3 4
250 32 19
3
.189.1' --1:2**
41.0 **1.2
10.7 - . *1.4
A .
2.TT 1.1
12.3 1.4
12.3 1.3
4.8 1.6
2.3 . 1.9
*
. **
... .. 4
2.8 0.3
- 3.8
1.2
. . ' ....
4 44
106.6
1.4**
14.7 0.7
7.5 0.8
... '
30.354.7 4.737
443
... Ci'
* Rates wen adjusted for age, sex, race, and calendar year using the total study population as the standard papulation; rates wen not included when
__ the observed number of deaths was less than five ..............
____________ _
____ _______ __ .
_
t For 704 subjects, accounting for 98 deaths, a category could not be assigned because of missing data
i ICDA. eighth revision codes shown in parentheses
.
..
. :
Rate ratio (RR): ratio of rates of potentially exposed subjects to those of nonexposed subjects; statistical significance at p<.05 is indicated by **
tween the occupational groups. Smokers incurred a higher risk of mortality from most causes of death when com pared with nonsmokers, regardless of occupational cate gory. In the nonexposed category, technicians who had the highest death rates for malignant neoplasms also had the highest percentage of smokers, while the profession als with the lowest death rates also had the lowest per centage of known smokers, in the potentially exposed category, the distribution of smokers was similar and the death rates were also similar among the five occupational categories. It appears thatdifferences in death rates across occupational subgroups could be explained to great ex tent by differences in smoking history. Other studies have shown that cigarette consumption is higher among bluecollar workers as compared with white-collar workers.'0 Since the majority of the potentially exposed workers in our study could be classified as blue-collar workers, our results are consistent with these findings. There remains a slight excess in mortality for potentially exposed as com pared with nonexposed workers allowing for smoking dif ferences. However, the data on which this report is based do not allow further conclusions to be drawn because the numbers of deaths are too small in occupation-and smok ing-specific subgroups to permit further analysis. With
365
EM003064
smoking histories unavailable for 30% of the study pop ulation, it is not possible to separate out completely the effects of smoking from potential effects of a specific oc cupation. The exposed and nonexposed groups also may have varied with respect to other socioeconomic factors that could be related to mortality outcome. Expansion of this cohort over time and across other similar worker pop ulations may help us to identify the possible effects of such confounders as educational level, family history, di etary intake, alcoholic consumption, and other presently unknown factors that may become apparent in the future.
Summary
''
A cohort of 21,698 U.S. refinery and chemical plant
workers was observed for eight years to determine if there
were interplant variations in causes of mortality. Mortality
outcomes were analyzed by geographic site, by occupa
tional subgroups, and by smoking history. Mortality from
cancer of the pancreas was highest in the Baton Rouge
cohort, while mortality from digestive and respiratory can
cers was highest in the Bayway Bayonne cohort. These
interplant variations in mortalitywere consistent with known
geographic variations. Only kidney cancer rates were con
sistently higher than those of the U.S. population for all
Mortality Study/Hams et ai
\
% vWF Trth 7 _ ofrarrH My1*"1 of Onto aadOirectty Adjasttoi-Martallty Rata* par 10,000 Parsoo-Yeirs tor _ . Naoplaama by 0ccggtiPBr1970 through 1977.......... ..... .........' '----
' : 'OCCWUWI
dfiLft
'iMK'. btoamfr
totaoS
HlWlWlH
bt*OfTu
hwami
S.K. s ?
Csutt it Orth*
Officiitt^c
- *n t
A cv Offie*1
MMHtri.* Pniraiauti ' TtcMcian' Cltrirt Opmtan
(N>80t)v (N>2.471) (N-2H) (*>1.411) (N >0.135)
Oigesuve organ cancer 150-159) ` * ' Pancreatic canctrit57i
Aesoirarory system cancer<160-163) Lung cancer H62I.
kidney oncer 'T8JT-' . f.tcS.CC
Bran CHS cancer ~Zr
=19M92.
ft.*
<5*ai \.oi
13!O.t )2l '
(2l (Ol iti
11.0 ri2i
3.f
<21 11.9 (12) 11.9 ' 112)
32
(01
l3>
m .-r 12)
6.7 (6)
HI 3.12) r . 121
It) 15.0
03) 15.0 (13)
(1)
f
'5E ;w
Sifti *)
i2> ,V! . M*
.. *r15.3 * "f(S6) S.*-S2.6 . c l (10)
- 19.4 "'(5S) , 15.9
f 153)
m *
(21
lOi.-..
. iti 111 121
fxwBiiiv Eitorac
1*2*3 ^ JS1US3
rectorial .oca.nr.". Unkt-
Wwttn... _Lwiri .. Wffitra Prelimaili =' U.S.I
(tt>7.1tn' (4*1.572)" (4-471) ^4M1) (Mf
12.4 (70) 3.2 (IS)
nriarp.1p64r?,,/ ' W*;:Kiea*R ... '
' '>" OS r (6) "(O) ;.-.n*B*'(i)
15.5 17.0
aanhOi18 6
(90) (26)
15.1 16.4 _
(161 (25)
I.A (9) (2)^: -
.oftfeyjT
1.1 -n-.j.-':c=."3 ro ottteeT
(6) 10) : <'J .0* Sbl
___ 1.6_
(9).
.11) .
`2> .
O).
114.2
i 2.8
] 16.8
16.0
1 I 1.0 i 1.9
* Rates were adjusted for age. sex. race, and calendar year using the total study population as the standard population; rates were not calculated when
the observed number ot deaths was less than five
rw*cesis<; - c? '^aa . t ,- ninsraAfiji
t There were 704 missing work histories: of these. 88 were for decedents
-*iisiwus.*>cgie.ss-.v:s:5 .59*cm ret" m 'aa-.itfl
__ tJCOA. eighth revision codes shown in parentheses_________ ________________________ _________________
'
S Number>4otMfji}eafttahs- ^shown in parentteas^
-ssy
r.^.Of *eg 5*R.vr!!eftoM caEirjaA rssnQ _ 8t sidT .
i1 v.i.'' ?s;st) bus
beiBtng ifMil______ __________ _ __________ ust*-r: -)*3
. ._
. J
1 Table 8--Obsarnd Number of Deaths and Diractty Adjusted* Mortality Rates per 10,000 Person-Years tor Selected Causes
-aa=. v- j... u.u jj De|thi |jy smoklnn History. 1970 throuoh 1977
_
.
-nr.-. - Cause of Deatbt
All causes (000-999) . i `
All malignant neoplasms (140-209)
All digestive organs (150-159)
Liver/gallbladder/bile ducts (155-156)
Pancreas (157)'
All respiratory system (160-163)
Lung (162)
'
. All genitourinary organs (180-189)
Prostate (185)
Bladder (188)
'
Kidney (189)
Brain/CNS (191-192)
All lymphopoietic (200-209)
' Lymphosarcoma/reticulosarcoma (200)
Leukemia (204-207)
Diseases of circulatory system (390-458)
Diseases of respiratory system (460-519)
Diseases of digestive system (520-577)
Diseases of genitourinary system (580-629)
`' Ever Smoked
Observed No.
Rate
1,566 377 96 10 24 146 142 44 22 7
15 9 31 7 12
908 77 52 - 19
254.9 57.1 14.5
1.3 3.7 22.2 21.6 '7.4 4.1 1.2 2.1 1.9 4.2 1.0 1.6 153.1 13.2 7.6 3.8
Never Smoked
'"'"Rate*
Observed No.
Rate
Ratio
208 - 131.5 -v 1 g..
43 24.5 '** 2.3"
17 9.2 1.6 2 ... * * V -
7 4.4 0.8
4 ... " ...
3 ... 12 8.4 ^'oi
10 7.3 0.6
... " . . .
1 ...
...3 ... ' r3
4
2 1
......
134 92.0 -A7** 7 3.8 .3.5" .
7 3.4 )2.2"
7 4.0 ---1.0"
Total No. of person-years Total No. of employees Total No. of deaths
74,362.7 11.105
1.566
-
26.418.3 4,059
208
Rates were adjusted for age, sex. race, and calendar year using the total study population as the standard population; rates were not
the observed number of deaths was less than five
.
'
t ICDA. eighth revision codes shown in parentheses
"
t Ratio of rates for those who ever smoked to those who never smoked: statistical significance at p<.05 is indicated by a double asterisk
when -
Journal of Occupational Medidne/Vol. 27. No. 5/May 1985
367
- Table# -SJtacDy Adjusted* Mortality Rates par 10,000 fosoo-Years tor Deaths Qua to Selected Causes, by-Occapational
w2.<in- . .r i .i -- rCategory and Smoking History - mr.*
-
......
Senses of Death*
-------------------- Occupational Category*
Potentially Exposed
y *' 1
. Ever .. Never--------Ratal ........-Ever
Smoked
Smoked
Redo
Smoked
Nonexposed
Never Smoked
Rats$ Ratio
All causes ofteth (000*999).
'
Diseases of crculatoiy system (390458)
----- Malignarttmeoplasms (140-209)
-~
Digestive organs (150-159)
Respiratory system (160-163)
Pancreas (157)
Kidney (109)
Brain (191)
leukemia (204-207)
279.7
142.6____ 2.0**.180.2 *
169.0
100.6 " /1.7**:104.0
-62,1 -------26r2 - 2.4** ----42.6
16.0 10.0 1.6
9.9
24.2 .......................
16.7
3.9 4.8 0.8
3.0
2.3
...
1.0 ...
...
1.8 ... ...
...
.
99.6 1.8** 66.5 . 1.6 19.4 --2.2**
* ... ... - . . . . . ... . . ... . .., ... ...
Total No. of Person-years Total No. of employees Total No. of deaths
103,360.1 16,257 2.658
30,354.7 4,737 - 443
* Rates were adjusted for age. sex. nee. and calendar year using the occupational subgroup as the standard population: ntes were not calculated when
the obsenrefl number ol deaths was less than five
' `'
' ' " ' ``
`
t For 704 subjects, accounting for 98 deaths, a category could not be assigned because of missing data
-
t JCM-eighth revision codes shown in parentheses
'
$ Ratio of ever to never smoked: statistical significance at pc.05 is indicated by a double asterisk
'
' '"
Table 10 -- Directly Adjusted* Mortality Rates per 10,000 Person-Yeais tor Deaths Oue to Selected Causes, by Smoking History
and Occupational Categoryt
.
- i i ------------ - ` " Cause of Death*
Ever Smoked ---- ' - --***- . Ratej
Potentially Exposed Nonexposed Ratio
Never Smoked
.. -- --
--
-- i'll*..
Potentially Exposed Nonexposed
Rate) Ratio
All causes of death (000-999) --
Diseases of circulatory System (390-458)'
Malignant neoplasms (140-209)
Digestive organs (150-159)
Respiratory system (160-163)
Pancreas (157)
Kidney (189)
Brain (191)
Leukemia (204-207) .
.......... 256.8 (1.321)1 158.7 (783) 58.0 (321) 14.4 (83) 24.4
(129) 3.4
(19) 2.1
(13) ...
(4) 1.5 (10)
"l-7214.2
(210) 115.7
" (HD
48.7
(52) 12.0
.(ID
14.0 (16)
3.4
(5) ..
(2) 3.0
(5) .
(D
Total No. of person-years
Total No. of employees
Total No. of deaths
'
74,362.7 11,105 1,566
1.2** 1.4*" 1.2 1.2 1.7 1.0
,.
.. ..
128.9 (158)
88.2 (103)
25.9 (34)
9.7 (14) (3)
4.8
(6)
(D
...
(2) ...
(D
' "12519 (43) 83.6 (26) 21.7
(8) ...
(2) ...
(D
(i)
....
(0)....
(D
(0)
26,418.3 4,059 . 208
1.0 1.1 1.2 ,,. *...
,,,
... ...
Rates were adjusted for age. sex. nee. and calendar year using the total study population as the standard populabon: ntes were not accounbng tor
98 deaths, calculated when the obseived number of deaths was less than five
t For 704 subjects, a category could not be assigned because of missing data
* ICDA. eighth revision codes shown in parentheses
Ratio of ntes of potentially exposed workers who ever smoked to those of nonexposed workers who ever smoked: statistical significance at pc.05 is
indicated by a double asterisk
I Ratio of ntes of potentially exposed workers who never smoked to those of nonexposed workers who never smoked
-
n Number of deaths shown in parentheses
.
368 Mortality Study/Hanis et al
EM003066 \
4
three plant sites; Variations In mortality were observed by *
occupation- and smoking history. This study could not
completely discriminate between the effects of smoking
and the possible contributory effect of occupation on -
mortality outcome. However, substantially higher death rates among smokers as compared with nonsmokers per>
sisted regardless of occupational classification and, in*
deed, contributed more to observed differences than did
occupation.
.. ;
References
- .- -
1. Hails NM, ShaHenberger LG. DonalesU DL et ai: A retrospec
tive- mortality study of workers in three major U.S. refineries and
chemical piano, Fait I. Comparisons with U.S. population. / Octtip
Med 27:283492,196S.
.
2. Cotton T: Statistics in Mcdkkie. Boston: Uttte Brawn 6 Co.,
1974, pp 47-49.
' .
3-MonsonM: Analysis of relative survival and proportional mor-
talky. Computers Bkxned Res 7J2S-ZS2.1974.
'4. Mantel N.HaensaeIWi Statistical aspects ol the analysis ol data from retrospective studies of disease./NO 22^19440,1959. ` S. Mantel N: Evaluation of survival data end two new rank order
statistics arising from its consideretion. Cancer Chtmother Rep 30:163 170,1966.
6. Stagg V. Eng-Hul Can, Kwardak l: Computer Program for Ap plication of Mantei-HeentzeiTest with Confounders, version 3.1. Uni versity of Western Ontario, 1982.
7. Mason T), McKay FW, Hoover R, et a): Adas of Cancer Mortality
forU.5. Counties: 19S0-1969. U.5. Dept Health, Education, and Wel
fare, 197S.
6. MacMahon B, high IF: Epidemiology Principles and Methods.
Boston: Uttie Brown t Co., 263,1970.
.
9. IhomasTL, Dccoufle P, Moure-Eraso ft: Mortality among work
ers employed in petroleum refining end petrochemical plants. / Oc-
cqp Med 22:97-103,1900.
10. Covey IS, Wynder EL: Smoking habits and occupational status.
/ Ocojp Med 23:537-542,1981.
.
Journal of Occupational Medicine/Vol. 27. No. 5/May 1985
EM003067
369