Document 33oRvBoqdL71MrKdXmnVrKjO
.J
n
ported by a grant front the City of Birmingham, for his skillful assistance with the analytical work. They are also grateful to the staff of the City of Birmingham Dental Clinics for supplying teeth
for analysis. Accosted for publication June 26, 1976. Articl^copies are available from Dr. Harry A. Waldron, Depart
ment of Social-Medicine, ThP Medical School, Birmingham BIS 2TJ, United Kingdom.
*V^* ******
REFERENCES
1. Sttehlow, C.D. 1972. The use ofdeciduous teeth as indicators of lead exposure. Ph.D. dissertation. New York University.
2. Needleman, H.L.; Davidson, I.; Sewell, EAL; and Shapiro, 1-M. 1974. Subclinical lead exposure in Philadelphia schoolchildren:
Identification by dentine lead analysis. N Engl /'Med 290: 245-. 48. '' J/ 3. Altschuler, L.F.; Halak, D.B.; Landing, B.H.: and KehoejJJKA. 1962. Deciduous teeth as an index of body burden Sad.' J Pediair 60: 224-29. 4. Needleman, H.L.; Tuncay, O.C.; and Shapirps'flM. 1972. Lead levels in deciduous teeth of urban and suburban American children.Nature 235: 111-12. 5. Stewart, DJ. 1974. Teeth as indicators: cof exposure of children to lead. Arch Dis Child 49^895-97. 6. Kaneko, Y.; Inamori, Lyhnd Nishimura, M. 1974. Zinc, lead,. copper, and cadmium-m human teeth from different geo graphical areas imjSpan.Ru// Tokyo Med Dent Univ 15: 233-
41. / 7. Shapiro, lAff; Mitchell, G.; Davidson, I.:and Katz. S.H. 1975.
The leadAontent of teeth: Evidence establishing new minimal levelsjet exposure in a living preindustrialized human populaiiapsArch Environ Health 30: 483-86. 8. Mackie, A.C., and Townshend, A. in press. Evaluation of pro/cedures for tooth lead analysis.Anc/yrr. 4* Lockeretz, W. 1975. Lead content of deciduo'us teeth of chil
dren in different environments. Arch Environ Health 30: 5S3-
10. Steadman, L.T.; Btudcvold, F.; Smith, F.A.<dardner, D.E.;
and Little, M.F. 1959. Trace elementsin'ancient Indian teeth.
/Dent Res 33: 285-91.
/
11. Pfrieme, F. 1934. Uber den norm'alen und pathoiogischen
Bleigehalt der Zahne von Menschen und Ticten./lrc/t Hyg Bakteriol 11: 232-42. X
12. Storozheva, N.N. 1963. Soderzhanie svitsa i dova v zubakh
cheloveka vnormeiprikariere.Stomatologist(Moskl 42: 4448. / 13. WilkinsoofD.R., and Palmer, W. 1975. Lead in teeth as a func tion ofage. Am Lab 41: 67-70. 14. Strdfilow, C.D., and Kneip, TJ. 1969. The distribution of
lead and zinc in the human skeleton. Am Ind Hyg Assoc J 30: 372-78.
15. Hoitzman. R.B.; Lucas. H.F.; and ilcewicz, F.H. I968.*Con-
centration oflead in human bone. Argonne National Labora
tory publication no. Anl-7615, pp. 4349. 16. Malik, S.R., and Fremlin.J. 1974. A study of lead distribu
tion in human teeth, using charged particle activation analysis. Caries Res St 283-89.
17. Mackie, A.C.; Stephens, R.; Townshend, A.; and Waldron. H.A. In press. Lead and caries. Caries Res.
18. Stack, M.V.; Burkitt, AJ.; and Nickless. C. 1975. Lead in
children's teeth. Nature 255: 169.
19. Joint Working Party on Lead Pollution around Gravelly Hill.
1975. Interim report. London: Department of the Envii ment.
20. Hunter, R.E.; KelsaU, KLA.; Bishop, WJ.; and
P.F. 1973. Abstracts ofthe 4th.lnternational Cc| Atomic Spectroscopy. Toronto, Ontario: Interi ference on Atomic Spectroscopy, p. 36>.
21. Chatman, T., and Wilson, DJ. 1975. Lead revels
deciduous teeth in Tennessee. Environ Lett 8: ll 22. Rytomaa, L., and Tuompo, H. 1974. Lead levels]
teeth.Natunvissenschaften 61: 363.
Cancer Mortality in Relation to
Asbestos in Municipal Water Supplies
DONALD T. V/IGLE, M. D, Phi)., MJJL Bureau of Epidemiology Health and V/etfare Canada Ottawa, Ontario
ABSTRACT
The mortality experience of twenty-two municipalities in Quebec grouped by evidence of exposure to asbestos fibers in water supplies (known high, possible high, and probable low exposures) was evaluated. Excess mortality due to cancer of the stomach (males), pancreas (females), and lung (males) was observed in fe'^v^-.uniripalitics with known high exposures. The excesses among mates may have been due to occupational exposure to asbestos. The absence of excess mortality due to pancreatic cancer among males suggested that the excess among females was not due to waterborne asbestos. The study therefore did nor reveal evidence of excess cancer mortality thit ronlrf he attributed to
ALTHOUGH ASBESTOS is a well-characterized car cinogenic agent when inhaled by humans,1 there is little evidence concerning its carcinogenicity when ingested. As bestos fibers were discovered in Lake Superior, the source . of municipal water for Duluth, Minnesota, in 1973. Further investigation revealed the presence of 1-30 million amphibole asbestiform fibers per liter in Duluth tap water sam ples. Contamination of the water supply with asbestos ap parently began in 19S5 as a result of the dumping of taconite mine-tailings into the lake. Thus, the studies re ferred to below1*3 probably did not include a sufficient time period to observe an increased risk of cancer due to exposure to waterborne asbestos.
A study of cancer mortality1 during four 5-year periods beginning in 1950 revealed that, relative to the state of Minnesota, the city of Duluth had significant excess mor tality due to several cancer sites at least one time period. The gastrointestinal sites involved were cancers of the esophagus, stomach, and rectum in white males, and can cers of the rectum and pancreas in white females. However, only the rate for male rectal cancer increased during the time periods subsequent to 1955-59; the female rectal can cer rate increased between 1950-54 and 1955-59, that is, before or soon after the dumping of taconite tailings began. An interval of 10 to 20 or more years before development of cancer would be expected for most human carcinogens.
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In another study, incidence rates during 1969-71 were significantly high in Duluth compared with Minneapolis .for stomach cancer (males) and compared with either Niinneapolis or St. Paul for cancer of the pancreas (both sexes), but were significantly lower in Duluth than in either comparison city fbr cancer of the large intestine.3
The present study was undertaken to evaluate cancer mortality in two municipalities, Thetford Mines and Asbes tos, where asbestos mining operations were established many years ago, in 1878 and 1882, respectively. Recent studies4 (R. W. Durham 1975:personaIcommunication) have revealed the presence of relatively high concentrations of asbestos fibers in'the municipal water supplies of Thet ford Mines and Asbestos. The asbestos deposits in the re gion of these municipalities consist mainly of chrysotile in serpentinized peridotite.5
Method
Tabulations of the number of deaths by three-digit rubrics of the International Classification ofDiseases, seventh revision (1964-68) and eighth revision, adapted for use in the United States (1969-73), 5-year age group, sex, and municipality were obtained from the Health Division of Statistics Canada. The 1966 and 1971 pop ulations by age, sex, and municipality were obtained from the Census Data Dissemination Division of Statistics Canada.
The municipalities included are as follows: In Group 1 (known high exposure)--Asbestos and Thetford Mines; in Group 2 (possible high exposure)--Black Lake, Drummondville, Drummondville Sud, Magog, Plessisville, Victor-
iaville, and Windsor; in Group 3 (probable tow exposure)Alma, Arvida, Becancour, Grand' Mere, Joliette, La Tuque, Nicolet, Rimouski, Rimouski Est, Riviere-du-Loup, Shawinigan, Shawinigan Sud, Sorel-Tracy, St. Hyacinthe, St. Jerome, and Ste. Therese.
The expected numbers of cancer deaths were calculated by applying the Quebec age-specific (5-year groups), sexspecific, site-specific, and period-specific (1965-67, 197072) mortality rates to the 1966 or 1971 census popula tions by age and sex for each municipality.
Results
Oiaracteristics of Grouped Municipalities
The locations of the municipalities in each of the three groups are shown on the map in the figure. The two towns with known high exposures (Group 1) and the six towns with possible high exposures (Group 2) are clustered within a radius of about 40 miles and either are immediately ad jacent to asbestos-containing deposits or obtain drinking water from rivers draining the region of such deposits. Towns with probable low exposures (Group 3) were sel ected from regions remote from the peridotite deposits shown in the figure. The available data concerning the concentration of asbestos fibers in the municipal water supplies are presented in Table 1. Hie results for Asbestos and Thetford Mines indicate asbestos fiber concentrations substantially higher than those for Drummondville (filtered) or Plessisville. There is a large discrepancy in the values repotted by the two sources for Thetford Mines, but both values are high.
Selected demographic characteristics of the three
Location of municipalities and peridotite deposits, lit. Asbestos; H2, Thetford Mines;/1/, Black Lake;/1.?, Drummondyille and Drummondville Sud;/1.?, Magog;/1-/, Plessisville;PS, VictoriavilIe;/1d; Windsor; LI, Alma; L2, Arvida;L3, Becancour; L4, Grand' Mere;LJ, Joliette; L6, La Tuque; L 7, Nicolet;S, Rimouski and Rimouski Est; 9, Rivere-du-Loup;L/C, Shawinigan and
Shawinigan Sud:HI, Sorel-Tracy; LI2, St. Hyicinthc;LU, Sr. Iwime; 1.14, Ste. Therese.
{
186 Archives of Environmental Health
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Table l.-Available Data for Asbestos Fibers in Municipal Water
Supplies
_______________
Municipality and Type of Water Supply Source
Reported Concentrations " of Asbestos Fibers in Municipal Water Supply
Asbestos Raw Filtered
1,200.000,000* 200,009,0097
Thetford Mines Raw Raw
172.000,000 1,300,000,000 f
Drummondville Raw Filtered
680,000,000* l,100,000t
Ptessisville Raw
13,000,0001
* Fibers per liter. 7 R. W. Durham 197S: personal communication.
$ See reference 4.
Municipal water supply is not filtered.
groups of municipalities are presented in Table 2. The three groups were quite similar with respect to mother tongue (French) and proportions of the labor force em ployed in major occupational groups 11-33 (professional, administrative) and 41-61 (clerical, sales, service). The average population was somewhat larger for Group 3 than for Group 1 or 2. Groups 1 and 2 had the highest proportions of the labor force in major groups 77 (min ing, quarrying) and 81-85 (processing, machining, pro duct fabricating), respectively.
General Mortality
The observed (0) and expected (E) numbers of deaths due to all cancer and all other causes by municipality group and sex are presented in Table 3. Significant excesses of cancer deaths were observed among males in Group 1 (0/E = 1.23) and females in Group 3 (0/E = 1.07). There were significant excesses of deaths due to all
Table 2.-Charactcristics of Grouped Municipalities
Characteristic
Group 1
Group 2
Group 3
(Known High (Possible High (Probable Low
Exposure) Exposure)
Exposure)
Number of municipalities
2
Population* Average Total
15,857 31,714
Percentage with French as mother tongue
95.9
Percentage in major occupation groupsf 11-33 41-61 77 81-85 Other
17.2
303 1U 16.2 25.0
6
15,603 93,620
97.2
15.8 33.2 0.8 . 26.8 23.3
14
21,028 294,396
96.6
18.9 33.7
0.1 19.9 27.4
t 11-33-manaieriaI, professional, artistic, literary, recreational; 41-61-clerical, sales, service; 77-mining, quarrying; 81-85processing, machining, product fabricating. Values shown represent the percentage of the experienced labor force, aged 15 years and over, for both sexes, in 1971.
other causes among males in all three municipality groups (O/E = 1.12,1.08, and 1.10) and among females in Group 3 (O/E = 1.10).
The distribution of mortality was also studied for the individual municipalities within each of the three groups (data not shown but available upon request). Significant excesses of deaths due to all cancer were observed as follows: Group 1--Thetford Mines (males, O/E = 1.3); Group 3--Joliette (males, O/E = 13), La Tuque (males, O/E = 13), Nicolet (females, O/E = 1.8), St. Hyacinthe (females, O/E = 1.2), and Ste. Therese (females, O/E = 13). The municipalities having significant excesses of deaths due to all other causes were: Group 1--Asbestos (males, O/E = 13); Group 2--Drummondville (males, O/E = 1.1); Group 3--Alma (females, O/E = 1.4), Joliette
(males, O/E = 13; females, O/E =1.1), Nicolet (females, O/E = 13), Riviere-du-Loup (males, O/E = 1.2), Sorel-
Tabte 3.-Mortality Due to All Cancer and AH Other Causes
Cause of Death,
Group 1
(Known High Exposure) ....... - "
Group 2
(Possible High Exposure) " ..... .
and o
Sex
Obs
Exp*
O/E Obs
Exp
O/E
All cancer M F* T
195 127 322
153.4
1383 296.6
1.23 2 0.92 1.09
457 415 872
466.0 4083
874.9
0.98
1.01 1.00
Other causes M F T
601 259 860
536.2 285.4 821.6
1.121 1,690
0.91
893
1.05 2,583
NOTE: The 25-74 age group was considered.
`See Methods section of text, fP <.05, by the chi-square test. %? <.0l, by the chi-square :est.
1.562.1 858.3
2,420.4
1.08$
1.05 1.072
Group 3 (Probable Low Exposure) *""'*"*"~~"*"""
Obs Exp O/E
1,433 1302 2,735
1,389.8 1319.8 2,609.6
1.03 1.077 i.ost
5,148 2,809 7.957
4,679.1 2,548.3 7,227.4
1.10 1.10$
1.10$
July/August 1977
187
ASARCO ELP 0004113
Tracy (males, O/E = 1.1), St. Hyacinths (males, 0/E = 1.1; females, 0/E = 1.1), and Ste. Thcrese (females, 0/E = 1.2).
Cancer Mortality
The observed and expected numbers of cancer deaths by sex, site, and municip'ality group are presented in Table 4. Significant excesses of cancer deaths were ob served as follows: Croup 1--stomach (males), pancreas (females), lung (males); Group 2-prostate (males), kidney (females), brain (males), lymphoma (females); Group 3-large intestine except rectum (females), uterus except cervix (females), and kidney (females).
The distribution of gastrointestinal cancer by age
group, sex, and aggregated sites is presented in Table 5. Significant excesses of cancer deaths were observed for the following: Group I-upper gastrointestinal (females aged 75 and over, and total); Group 3--large intestine and rectum (males aged 75 and over); and total gastroin testinal (males aged 75 and over).
Discussion
Studies of workers exposed to asbestos have revealed excess mortality due to gastrointestinal cancer* *7 and abdominal mesotheliomas.4'9' Such observations may in dicate that exposure to asbestos via the gastrointestinal tract (presumably from swallowed sputum in workers exposed to airborne asbestos) increases the risk of cancer
Table 4.-Cancer Deaths by Sex and Major Site
Croup 1 (Known High Exposure) Site Sex Obs Exp* O/E
Croup 2 (Possible High Exposure)
Obs Exp O/E
Group 3 (Probable Low Exposure)
Obs Exp O/E
Buccal cavity and pharynx Esophagus
' Stomach
Large intestine except rectum Rectum
Pancreas
Lung
Breast Cervix uteri Other uterus OVary Prostate Kidney
Bladder
Brain
Lymphoma
Leukemia
Other
M F
M F
M F
M F
M F
M F
M F
F
F
F
F
M
M F
M F
M F
M F
M F
M F
4 1
3 1
24 10
IS 14
4 4
89
78 10
29
7
7
9
9
2 2
4 1
2 1
6 3
6 2
27 17
5.8 1J
3-5 1.1
17.4 8.7
14.0 16.8
7.0 5.0
8.4 5.2
46.8 7.7
35.0
8.7
7.1
8.6
7.7
3.8 2.1 6.0 1.S
4.8 3.6
8.8 6.5
5.4 3.7
19.0 15.4
0.7 ... ... ... 1.4f 1.2 1.3 0.8 0.6 0.8 1.0 1.7f 1.7$ 1.3 0.8 0.8 1.0 1.0 1.2 ...
0.7 ...
...
0.7 0.5 l.l --
1.4f 1.1
11 17.0 0.6f 3 4.4 ...
5 10.5 0.5t 2 3.2 .
47
51.6
0.9
35
26.0
1.3
41
41.0
1.0
57
50.5
1.1
20
21.3
0.9
9 14.8 0.6$
29 24.8 1.2 18 15.7 1.1
106 137-5 0.8$
17
22.9
0.7
106 98.8 1.1
26 25.0 1.0
19 21.1 0.9
22 25.4 . 0.9
44 24.1 1.8$
9 10.9 0.8 10 6.3 1.6f
10 18.0 0.6f ' 2 4.5 --
25
13.3
1-9$
5
10.5
0.5f
30 25.0 1.2
24
19.2
1.3f
18 15.7 1.1 9 10.9 0.8
62
55.3
l.l
51 49.7 1.0
54 50.8 9 13.0
26 30.8 3 9J
145 153.6 91 77.1
126 122.2 176 149.4
51 61.5 44 43.8
91 74.2 44 46.8 392 ' 409.9 54 68.5
303 305.5
74 75.3
80 62.3
75 75.8
81 70.9
28 32.6 24 18.9
51 53.0 11' 13.4
42 40.3 37 31.7
86 74.5 S9 57.5
56 46.9 35 32.6
204 167.6 183 138.7
1.1 0.7
0.8 0.3|
0*9 1.2
1.0 1.2f
0.8 1.0
1.2 0.9
1.0 0.8
1.0
1.0
1.3i
1.0
1.1
0.9 1.3f
1.0 0.8
1.0 1.2
1.2 1.0
1.2 1.1
1.2$ 1.3$
NOTES: Only the 25-74 year age group was considered. O/E was not calculated if E (expected number of deaths) was less
than 5. See Methods section of text. jP <-.05, by the chi-square test if E>20 and by Poisson distribution if E <20.
tP <.01, by the chi-square test if E 20 and by Poisson distribution if E <20.
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Table 5.-Castrointestinal Cancer Mortality By Aggregated Sites. Age, and Sex
Ctoup 1 (Known High Exposure)
Croup 2 (Possible High Exposure)
Cancer Site
Sex
Age Obs
E\p" O/E
Obs
Exp
O/E
Upper gastrointestinal! M
25-74
75+ Total
31
11 4
26.8 10.7 37.5
1.2 1.0 1.1
63 51 114
78.9 39.1 118.0
0.8 1.3 1.0
F
25-74 12
11.2 1.1
40
33-5 1.2
75+ 11
5.3 2-lt 27
22.6 1.2
Total 23
16.5 l.4f 67
56.1 1.2
Larzc intestine and icctum
M
25-74 75+ Total
22 3
25
20.9 1.1
61
8.8 0.3f 33
29.7 0.8
94
62.3 1.0 32.5 1.0
94.3 1.0
Total
F
25-74 18
21.8 0.8
66
65.2
1.0
75+ 8
9.7 0.8
39
41.5
0.9
Total 26
31.5 0.8 105
106.7
1.0
M
25-74 53
47.7 1.1 124
14121
0.9
75+ 14
19.5 0.7
84
71.6 . 1.2
Total 67
67.2 1.0 208
212.8
1.0
F
25-74 30
33.0 0.9 106
98.7
1.1
75+ 19
15.0 1J
66
64.1
1.0
Total 49
48.0 1.0 172
162.8
1.1
Croup 3 (Probable Low Exposure)
Obs Exp
O/E
225
235.0
1.0
118 106.8 1.1
343
341.8
1.0
103 99.5 1.0
70
70.9
1.0
173 170.4 1.0
177 183.7 1.0 115 89.4 1.31 292 273.1 1.1
220 191.6 1.1 136 130.0 . 1.0
356 321.6 1.1
402 418.7 1.0
233
196.2
1-21
635 614.9 1.0
323 291.1 1.1 206 200.9 1-P 529 492.0 1.1
See Methods section of text. fp <.05, by the chi-square test if E (expected number of deaths) >20 and by Poisson distribution if E <20. *p <.01, by the chi-square test if E >20 and by Poisson distribution if E <20.
Buccal cavity, pharynx, esophagus, and stomach.
in tissues directly or indirectly exposed to the fibers. This possibility has caused some concern about the presence of asbestos fibers in municipal water supplies both in the United States2,3 and in Canada.4 ,l
The present study revealed some evidence of excess mortality due to gastrointestinal cancer in the two munic ipalities in Croup 1 (known to have water supplies con taining high concentrations of asbestos fibers). The individual sites for which there were statistically signif icant excesses of gastrointestinal cancer in these two municipalities were the stomach (males) and the pancreas (females). In Duluth, a significantly high incidence of pancreatic cancer was observed in both sexes. The present study does not support an association between pancreatic cancer and exposure to asbestos fibers in drinking water, because there was no excess among males. The excess stomach cancer among males may reflect occupational exposure to asbestos;'the absence of an excess among females argues against a role for waterborne asbestos. Ex cess mortality due to stomach cancer has previously been observed in asbestos workers.4 ,T
The excess male mortality due to lung cancer observed for the two municipalities in Croup 1 (Asbestos and Thetford Mines) was mainly due to an excess in Thetford Mines (O = 58, E = 31.6). This observation is consistent with the reportedly higher prevalence of opacities, pleural thickening, and pleural calcification, as diagnosed by chest roentgenography of asbestos workers,11 in Thetford Mines than in Asbestos.
The substantial excesses of deaths due to prostatic and
brain cancer among males in Group 2 municipalities (pos sible high exposure to asbestos) deserve further investigationj but do not appear to be related to waterborne asbes tos since similar excesses were not observed in Group 1, and the excess of brain cancer in Group 2 was confined to males.
Conclusion
A study of twenty-two municipalities in Quebec did not reveal excess cancer mortality that could be related to the presence of asbestos fibers in drinking water supplies. Ex cess mortality due to stomach and lung cancer among males in two municipalities (Asbestos and Thetford Mines) may reflect occupational exposure to asbestos.
*******'
The tabulation of mortality data by John Silinj and Pio Uran and the assistance in data analysis by M. Honora Smith are grate fully acknowledged.
Submitted December 21,1976; accepted for publication February 28,1977.
Article copies are available from Dr. Wigle at the Bureau of Epidemiology, L. C. D. C., Health and Welfare Canada, Tunney't Pasture, Ottawa, Ontario, K1A OL2, Canada.
**********
REFERENCES
1. Report of the Advisory Committee on Asbestos Cancers to the Director of the International Asency for Research on Can cer. Br] Ini-.tir.ryid 30(1973): 180-86.
July/August 1977
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ASARCO ELP 00041 IS
2. Mason, T. J.; McKay, F. \V.: and Miller, R. W. 1974. Asbestos like fibers in Duluth water supply: Rclacion to cancer mortality. JAMA 22S: 1019-20.
3. Levy, B. S.; Sifurdson, E.; Mandcl, J,; Laudon, E.; and Pearson, i. 1976. Investigating possible effects of asbestos in city water: Surveillance of gastrointestinal cancer incidence in Duluth, Minnesota. Am J Epidemiol 103:362-68.
4. Cunningham, II. M,, and Pontefract, R. D. 1971. Asbestos fibres in beverages and drinking water. Nature 232: 332-33.
5. Gibbs, G. \V,, and Lachance, M. 1972. Dust exposure in the chrysotile asbestos mines and mills ofQuebec.Arch Environ Health 24; 189-97,
6. Solikoff, I. J.; Hammond, E. C.; and Churg, 1. 1968. Asbestos exposure, smoking, and neoplasia. JAfilA 204: 104-10.
7. McDonald, J. C.; McDonald, A. D.; Gibbs, G. W.; Sicmiatycki.
1.; and Rossiter,C.E. 1971. Mortality in the chtysotile asbestos mines and mills of Quebec. Arch Environ Health 22: 677-B6. 8. Ncwhouse, M. L.; Berry, G.; Wagner, J. C.: and Turok, M. U. 1972. A study of the mortality of female asbestos workers. BrJ Induttr Med 29: 134-41.
9. Sctikoff, 1.1A Hammond, E. C.; and Churg. i. 1972. Carcin ogenicity of amositc asbestos. Arch Environ Health 25: 183-86.
10. Kay, G. 1973. Ontario intensifies search for asbestos in drinking water. Water Pollut Control (Sept. 1973): 33-35.
11. McDonald, 1. C.; Bccktakc, M. R.; Gibbs, G. W.; McDonald,
A. D,; and Rossiter, C. E. 1974. The health of chrysotile asbestos mine and mill workers of Quebec. Arch Environ Health 28: 61-68.
Director of Environmental Health Engineering
for Bethlehem Steel Corporation
Our Environmental Quality Control Division has an opening for an experienced Environmental Health (Industrial Hygiene) Engineer to direct our Environmental Health Engineering Program. Required qualifications are:
An undergraduate engineering degree with a graduate degree in environmental health (industrial hygiene); 5 to 10 years experience in the technical aspects of workplace evaluations and the application of engineering control techniques; and several years experience in administering a comprehensive industrial hygiene engi
neering program. Excellent benefits, opportunities for further study, ultra-modem facilities, and attractive working con
ditions in a pleasant cultural community.
Send, resume and salary requirements in confidence to;
Dr. D. M. Anderson. Manager -
Environmental Quality Control
Bethlehem Steel Corporation
Bethlehem, PA 18016
AnEqual Opportunity Employer
Choice of constant-flow demand or pressure-demandflow systems to protect workers in toxic atmospheres not immediately hazardous to life or health'. Variety of facepieces, as well as spe cial hoods for working with
abrasives, sandblasting and lead grinding. Write for details to M$A. 600 Penn Center, Pittsburgh. Pa. 15235.
Make sure/check MSA
190
Soft, snug, effective. Accu-FitTM and Ear Defenders5Earplugs.
Comfortable enough to wear all shift to guard against noise considered harmful on long exposure. Accu-Fic Ear Plugs are pliable, with one size to fie most people. Ear
Defenders come in five sizes with EarscopeTM gage to find
correct size. Write for more details to MSA. 600 Penn Center. Pittsburgh, Pa. 15235.
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