Veterans and Agent Orange Update 2000 (2001) / Chapter Skim
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7 Cancer
7 Cancer
Pages 248-398
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From page 248... ...
In assessing a possible relation between herbicide exposure and risk of cancer, one key issue is the level of exposure of those included in a study. As noted in Chapter 5, the detail and accuracy of exposure assessment vary widely among the studies reviewed by the committee.
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From page 249... ...
Prostate cancer incidence, for example, is nearly 11 times higher in men age 55-59 than in 45-49-year-olds and more than twice as high in African Americans age 45-59 as in whites of this age group (NCI, 2000~. The figures presented for each cancer are estimates for the entire U.S.
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From page 250... ...
Risk factors besides age and race vary for these cancers but always include family history of the same form of cancer, certain diseases of the affected organ, and dietary factors. Cigarette smoking is a risk factor for pancreatic cancer and may also increase the risk of stomach cancer (Miller et al., 1996~.
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From page 251... ...
The first study of mortality through 1987 among these workers (Fingerhut, 1991) found a slight excess cancer mortality for all cancers combined (standardized mortality ratio [SMR]
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From page 252... ...
This value was estimated for each member of the cohort by measuring serum TCDD levels for 144 subjects, including production workers known to be exposed to dioxins, workers in herbicide production, nonexposed production workers, and workers known to be exposed as a result of an accident that occurred in 1963. By assuming first-order TCDD elimination with an estimated half-life of 7.1 years, TCDDmaX was extrapolated for 47 of these workers, and a regression model was constructed to estimate the effect of exposure as a result of
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From page 253... ...
, proportionate cancer mortality ratio, or mortality odds ratio studies) ; 88 studies of industrial cohorts; 7 industry-based nested casecontrol studies; and 43 population- or hospital-based case-control studies.
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From page 254... ...
There was more limited evidence of increased risk for organochlorine pesticides, silica, and aliphatic and alicyclic hydrocarbon solvents. There was no evidence of increased risk with herbicide exposure.
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From page 255... ...
For malignant neoplasms of the colon and rectum, no excess risk was seen for the Ranch Hand veterans after analyses were adjusted for covariates. Approximately 50,000 members of the Australian Defence Force and Citizen Military Forces served in the Vietnam theater over the war years.
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From page 256... ...
An update of a cohort of Dutch chemical workers found no significant excess of GI cancer among the workers exposed to phenoxy herbicides or chlorophenols. A meta-analysis of studies of pancreatic cancer and occupational exposures found no evidence of associations with herbicide exposures.
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From page 257... ...
Studies Reviewed in Update 1996 Blair et al., 1993 U.S. farmers in 23 states White males Nonwhite females Bueno de Mesquita et al., Phenoxy herbicide workers 1993 Collins et al., 1993 Monsanto 2,4-D production workers Kogevinas et al., 1993 IARC cohort female Studies Reviewed in VAO 657 1.0 (1.0-1.1)
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From page 258... ...
0 (0.0-3.7) Solet et al., 1989 Alavanja et al., 1988 Bond et al., 1988 Thomas, 1987 Coggon et al., 1986 Robinson et al., 1986 Lynge, 1985 Blair et al., 1983 Burmeister et al., 1983 Wiklund, 1983 Burmeister, 1981 Axelson et al., 1980 ENVIRONMENTAL New Studies Bertazzi et al., 2001 Bertazzi et al., 1998 Paper and pulp workers USDA agricultural extension agents Dow 2,4-D production workers Flavor and fragrance chemical production workers British MCPA production workers Paper and pulp workers Danish male production workers Florida pesticide appliers Iowa residents Farming exposures Swedish agricultural workers 2,599 Farmers in Iowa 338 Swedish railroad workers total exposure 3 Seveso residents 20-year follow-up Zone A males Zone A females Zone B males Zone B females Seveso residents 15-year follow-up Zone A females Zone B males Zone B females Studies Reviewed in Update 1998 Bertazzi et al., 1997 Seveso residents 15-year follow-up Zone A females Zone B males Zone B females Zone R males Zone R females Swedish fishermen, mortality East coast West coast Swedish fishermen, incidence Svensson et al., 1995 East coast 24 West coast 71 Studies Reviewed in Update 1996 Bertazzi et al., 1993 Seveso residents 10-year follow-up, morbidity Zone B males 7 Zone B females Zone R males Zone R females 1.4 26 0.9 (0.6-1.3)
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From page 259... ...
Hooiveld et al., 1998 Dutch chemical production workers 3 1.4 (0.3-4-0) Rix et al., 1998 Danish paper mill workers Males 58 1.0 (0.7-1.2)
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From page 260... ...
farmers in 23 states White males Bueno de Mesquita et al., 1993 Collins et al., 1993 Studies Reviewed in VAO Ronco et al., 1992 Swaen et al., 1992 Fingerhut et al., 1991 Manz et al., 1991 Saracci et al., 1991 Zober et al., 1990 Alavanja et al., 1989 Henneberger et al., 1989 Solet et al., 1989 Alavanja et al., 1988 Bond et al., 1988 Thomas, 1987 Coggon et al., 1986 Hoar et al., 1986 Robinson et al., 1986 Lynge, 1985 Blair et al., 1983 Wiklund, 1983 Thiess et al., 1982 2,291 1.0 (0.9-1.0) Phenoxy herbicide workers Monsanto 2,4-D production workers Danish male self-employed farm workers 277 Dutch herbicide appliers 4 NIOSH cohort 25 German production workers 8 IARC cohort 41 BASF production workers basic cohort 2 USDA forest conservationists USDA soil conservationists Paper and pulp workers Paper and pulp workers USDA agricultural extension agents Dow 2,4-D production workers Flavor and fragrance chemical production workers British MCPA production workers 19 Kansas residents No herbicide use Herbicide use Paper and pulp workers Danish male production workers Florida pesticide appliers Swedish agricultural workers BASF production workers NS NS 0.7 (p < .05)
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From page 261... ...
Zone B females 3 0.6 (0.2-1.9) Studies Reviewed in Update 1998 Bertazzi et al., 1997 Seveso residents 15-year follow-up Zone A females Zone B males Zone B females Zone R males Zone R females Svensson et al., 1995 Swedish fishermen, mortality East coast West coast Swedish fishermen, incidence East coast 5 West coast 82 Studies Reviewed in Update 1996 Bertazzi et al., 1993 Seveso residents 10-year follow-up, morbidity Zone B males 2 Zone B females 2 Zone R males 32 Zone R females 23 2 2.6 (0.3-9.4)
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From page 262... ...
Rix et al., 1998 Danish paper mill workers 43 0.9 (0.6-1.2) Studies Reviewed in Update 1998 Kogevinas et al., 1997 IARC cohort Workers exposed to TCDD (or higher-chlorinated dioxins)
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From page 263... ...
Ramlow et al., 1996 Pentachlorophenol production workers 0-year latency 0 15-year latency 0 Studies Reviewed in Update 1996 Blair et al., 1993 U.S. farmers in 23 states White males Bueno de Mesquita et al., 1993 Studies Reviewed in VAO Ronco et al., 1992 Fingerhut et al., 1991 Saracci et al., 1991 Alavanja et al., 1989 Henneberger et al., 1989 Alavanja et al., 1988 Bond et al., 1988 Thomas, 1987 Coggon et al., 1986 Lynge, 1985 Blair et al., 1983 Wiklund, 1983 Phenoxy herbicide workers Danish male self-employed farmers NIOSH cohort IARC cohort USDA forest or soil conservationists Paper and pulp workers USDA agricultural extension agents Dow 2,4-D production workers Flavor and fragrance chemical production workers British MCPA chemical workers 8 Danish male production workers 14 Florida pesticide appliers 2 Swedish agricultural workers 1,083 ENVIRONMENTAL New Studies Bertazzi et al., 2001 Seveso residents 20-year follow-up Zone A males Zone B males Zone B females 367 1.0 (0.9-1.1)
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VIETNAM VETERANS New Studies AFHS, 2000 Air Force Ranch Hand veterans 7 1.5 (0.4_5.5) c AIHW, 1999 Australian Vietnam veterans male 188 221 expected (191-251)
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From page 265... ...
Bueno de Mesquita et al., 1993 Studies Reviewed in VAO Ronco et al., 1992 Swaen et al., 1992 Fingerhut et al., 1991 Saracci et al., 1991 Alavanja et al., 1989 Henneberger et al., 1989 Solet et al., 1989 Alavanja et al., 1988 Thomas, 1987 Coggon et al., 1986 Robinson et al., 1986 Phenoxy herbicide workers Danish self-employed male farm workers 137 Dutch herbicide appliers NIOSH cohort NIOSH cohort USDA forest conservationists USDA soil conservationists Paper and pulp workers Paper and pulp workers USDA agricultural extension agents 21 Flavor and fragrance chemical production workers British MCPA production workers 9 Paper and pulp workers 4 NS 0.6 (p < .05)
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From page 266... ...
VIETNAM VETERANS Studies Reviewed in Update 1998 Crane et al., 1997a Australian military Vietnam veterans 38 1.4 (1.0-1.9) Crane et al., 1997b Australian national service Vietnam veterans Studies Reviewed in Update 1996 Visintainer et al., 1995 Michigan Vietnam veterans 6 1.5
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From page 267... ...
and the hepatobiliary duct (ICD 9 155.1~. According to American Cancer Society estimates, 10,000 men and 5,300 women will be diagnosed with liver cancer in the United States in 2000; 8,500 men and 5,300 women will die from the disease (ACS, 2000a)
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From page 268... ...
Table 7-5 provides summaries of the results of studies underlying these findings and a list of reports that contain details of the research. Update of the Scientific Literature Occupational Studies The largest industrial cohort exposed to dioxins is the group of 5,132 U.S.
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From page 269... ...
Vietnam Veteran Studies In the Air Force Health Study final report (AFHS, 2000) , the small number of subjects with a malignant neoplasm of the liver (2 cases among 861 Ranch Hand veterans)
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From page 270... ...
provides a suggestion of an association between herbicide exposure and liver cancer; however, when considered with the overall body of evidence, this finding is not sufficient to change the conclusion that there is inadequate or insufficient evidence of an association. Conclusions Strength of Evidence in Epidemiologic Studies The result of this update is no change in the conclusion of inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides (2,4-D, 2,4,5-T and its contaminant TCDD, cacodylic acid, and picloram)
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From page 271... ...
chemical production workers 7 0.9 (0.4-1.6) Rix et al., 1998 Danish paper mill workers Males 10 1.1 (0.5-2.0)
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From page 272... ...
Studies Reviewed in Pesatori et al., 1992 Bertazzi et al., 1989D Hoffman et al., 1986 Stehr et al., 1986 VAO Seveso residents Zones A, B males Zones A, B females Seveso residents 10-year follow-up Zone B males Zone R males Residents of Quail Run Mobile Home Park O Missouri residents O VIETNAM VETERANS New Studies AFHS, 2000 Air Force Ranch Hand veterans Studies Reviewed in Update 1998 Crane et al., 1997a Australian military Vietnam veterans 8 Crane et al., 1997b Australian national service Vietnam veterans 1 Studies Reviewed in VAO 1.5 (0.5-4~0)
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From page 273... ...
Reported risk factors for nasal cancer include occupational exposure to nickel and chromium compounds (Hayes, 1997) , wood dust (Demers et al., 1995)
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From page 274... ...
Table 7-6 provides summaries of the results of the studies underlying these findings and a list of reports that contain details of the research. Update of the Scientific Literature Occupational Studies Caplan et al.
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From page 275... ...
Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides (2,4-D, 2,4,5-T and its contaminant TCDD, cacodylic acid, and picloram) and nasopharyngeal cancer.
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From page 276... ...
VIETNAM VETERANS New Studies AFHS, 2000 Air Force Ranch Hand veterans Studies Reviewed in Update 1998 Crane et al., 1997a Australian military Vietnam veterans Nasal cancer Nasopharyngeal cancer 9 1.0 (0.4-2.8)
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From page 277... ...
Table 7-7 provides summaries of the results of the studies underlying these findings and a list of reports that contain details of the research. Update of the Scientific Literature Occupational Studies The NIOSH cohort mortality study of 5,132 TCDD-exposed U.S.
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From page 278... ...
Incidence rates at 20 years were essentially unchanged and showed no pattern in the incidence rate over time (Bertazzi et al., 2001~. Vietnam Veteran Studies Ranch Hand participants have not shown an excess risk of laryngeal carcinoma or an exposure-response relationship among those cases that have occurred (AFHS, 2000~.
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From page 279... ...
Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is limited or suggestive evidence of an association between exposure to herbicides (2,4-D, 2,4,5-T and its contaminant TCDD, cacodylic acid, and picloram) and laryngeal cancer.
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From page 280... ...
b VIETNAM VETERANS New Studies AFHS, 2000 Air Force Ranch Hand veterans Studies Reviewed in Update 1998 Crane et al., 1997a Australian military Vietnam veterans 12 Crane et al., 1997b Australian national service Vietnam veterans 0 Watanabe and Kang, 1996 Army Vietnam veterans 50 Marine Vietnam veterans 4 4 0.6 (0.2-2.4)
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From page 281... ...
The rate for African-American males is consistently higher than for females or white males. The American Cancer Society estimates that more than 90 percent of lung cancers in males are the result of tobacco smoking (ACS, 1998~.
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From page 282... ...
plants where TCDD exposure had been documented. The relative risk for lung cancer, alone, was 1.1 (0.9-1.3, 125 deaths observed)
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, researchers reported 10 cases of lung cancer among Ranch Hands and 3 cases among comparisons (RR = 3.7, 0.8-17.1; Model 1, adjusted)
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From page 284... ...
Increased Risk of Disease Among Vietnam Veterans Although Ranch Hand participants show a markedly elevated risk of lung cancer, the extent to which this excess risk may be attributable to herbicide or TCDD exposure is not clear.
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From page 285... ...
chemical workers who developed chloracne Two highest cumulative exposure septiles Studies Reviewed in Update 1998 Gambini et al., 1997 Italian rice growers Kogevinas et al., 1997 Phenoxy herbicides: 36 cohorts Becher et al., 1996 Ott and Zober, 1996 Ramlow et al., 1996 Studies Reviewed in Update 1996 Asp et al., 1994 Blair et al., 1993 Bloemen et al., 1993 Kogevinas et al., 1993 Lynge, 1993 Studies Reviewed in VAO Bueno de Mesquita et al., 1993 Swaen et al., 1992 Coggon et al., 1991 Fingerhut et al., 1991 Green, 1991 Manz et al., 1991 Saracci et al., 1991 McDuffie et al., 1990 Zober et al., 1990 Wiklund et al., 1989a Bond et al., 1988 30 19 , Exposed to TCDD or higher PCDD Exposed to no or lower PCDD German chemical production workers BASE cleanup workers Pentachlorophenol production workers Finnish herbicide appliers U.S. farmers from 23 states White males Nonwhite males Dow 2,4-D production workers Female herbicide spraying and production workers Danish male production workers Phenoxy herbicide workers Herbicide appliers Phenoxy herbicide production workers TCDD-exposed workers 21-year exposure; 220 years' latency Herbicide sprayers in Ontario Phenoxy herbicide production workers Herbicide spraying and production workers Probably exposed subgroup Saskatchewan farmers applying herbicides 103 BASE production workers 6 High exposure 4 Chloracne 6 Pesticide appliers in Sweden 38 Dow 2,4-D production workers (15-year latency)
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From page 286... ...
Blair et al., 1983 Licensed pesticide appliers in Florida, lawn and ornamental herbicides only / u.9 (u.~-~.y) Axelson et al., 1980 Herbicide sprayers in Sweden 3 1.4 (0.3-4-0)
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From page 287... ...
Answer to question: Since your first day of service in Vietnam, have you been told by a doctor that you have lung cancer? BONE CANCER Background According to the American Cancer Society, approximately 1,500 men and 1,000 women will be diagnosed with bone or joint cancer (ICD 9 170.0-170.9)
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From page 288... ...
Summary of VAO, Update 1996, and Update 1998 The committee responsible for VAO found there to be inadequate or insufficient information to determine whether an association existed between exposure to herbicides used in Vietnam or the contaminant dioxin and bone cancer. Additional information available to the committees responsible for Update 1996 and Update 1998 did not change this finding.
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From page 289... ...
Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides (2,4-D,2,4,5T and its contaminant TCDD, cacodylic acid, and picloram) and bone cancer.
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From page 290... ...
TABLE 7-9 Selected Epidemiologic Studies Bone Cancer Estimated Exposed Risk Reference Study Population Casesa (95% CI) a OCCUPATIONAL New Studies Rix et al., 1998 Danish paper mill workers Males 1 0.5 (0.0-2.7)
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From page 291... ...
Studies Reviewed in Update 1998 Bertazzi et al., 1997 Seveso residents 15-year follow-up Zone B females Zone R males Zone R females VIETNAM VETERANS Studies Reviewed in Update 1998 Clapp, 1997 Massachusetts Vietnam veterans AFHS, 1996 Air Force Ranch Hand veterans 1 2.6 (0.0-14.4)
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From page 292... ...
45-49 Years of Age All Races White Black 50-54 Years of Age All Races White Black 55-59 Years of Age All Races White Black Males 3.2 3.0 4.1 4.1 4.1 5.2 Females 2.2 2.2 3.1 3.3 3.0 5.7 4.3 5.5 3.4 3.3 3.6 a SEER nine standard registries, crude age-specific rate, 1993-1997. Summary of VAO, Update 1996, and Update 1998 The committee responsible for VAO found there to be sufficient information to determine that an association existed between exposure to herbicides used in Vietnam or the contaminant dioxin and soft-tissue sarcoma.
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From page 293... ...
No STS deaths were observed among the workers exposed to phenoxy herbicides or chlorophenols in this study population. Environmental Studies In a review of early, mid-term, and long-term health effects, Bertazzi et al.
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From page 294... ...
Despite the strengths of the study, limitations include an unclear route of dioxin exposure and the fact that coexposures to chemicals other than dioxin from the incinerator could be responsible for the observed clusters. Vietnam Veteran Studies In the Air Force Health Study (AFHS, 2000)
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From page 295... ...
Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is sufficient evidence to conclude that an association exists between exposure to herbicides (2,4-D, 2,4,5-T and its contaminant TCDD, cacodylic acid, and picloram) and soft-tissue sarcoma.
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From page 296... ...
2 1.4 Workers exposed to any phenoxy herbicide or chlorophenol 9 2.0 (0.9-3.8) Ott and Zober, 1996 Workers exposed in 1953 accident 0 0.2 expected Ramlow et al., 1996 Pentachlorophenol production workers 0 0.2 expected Studies Reviewed in Update 1996 Kogevinas et al., 1995 IARC cohort Mack, 1995 U
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From page 297... ...
Lynge, 1985 Danish male production workers 5 2.7 (0.9-6.3, Balarajan and Acheson, 1984 Agricultural workers in England 42 Overall 1.7 (1.0-2.9, Those under age 75 1.4 (0.8-2.6, Blair et al., 1983 Florida pesticide appliers 0 Hardell, 1981 Swedish workers 52 Phenoxy herbicide exposure 5.5 (2.2-13.8) Eriksson et al., 1979, Swedish workers 5.1 matched 1981 (2.2-10.2)
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From page 298... ...
Studies Reviewed in Update 1998 Clapp, 1997 Massachusetts Vietnam Veterans Crane et al., 1997a Australian military Vietnam veterans Crane et al., 1997b Australian national service Vietnam veterans Comparison group AFHS, 1996 Ranch Hand veterans Comparisons Visintainer et al., 1995 Vietnam veterans Watanabe and Kang, 1995 U.S. Marines in Vietnam Studies Reviewed in Update 1996 Kogan and Clapp, 1988 Vietnam veterans in Massachusetts 9 Kang et al., 1986 Vietnam veterans Comparing those who served with those who did not 1.6 (0.5-5.4)
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From page 299... ...
and those that do not. The common nonmelanocytic skin cancers, which include basal and squamous cell carcinomas, have a far higher incidence than malignant melanoma but are considered less aggressive and therefore more treatable.
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From page 300... ...
The American Cancer Society estimates that approximately 1,900 individuals will die from these diseases in 2000. Skin cancers are far more likely to occur in fair-skinned individuals; the risk for whites is roughly 20 times that for dark-skinned African Americans.
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From page 301... ...
Hansen et al., 1992 Danish gardeners 32 1.1 (0.8-1.6) Lynge, 1985 Danish male production workers 14 0.7 Suskind and Hertzberg, 1984 Monsanto production workers 8 1.6 VIETNAM VETERANS New Studies AFHS, 2000 Air Force Ranch Hand veterans 325 1.3 (l.l-1.6 Ketchum et al., 1999 Ranch Hand (RH)
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From page 302... ...
(1998) conducted a retrospective cohort study of Dutch production and contract workers exposed to phenoxy herbicides, chlorophenols, and contaminants between 1950 and 1976.
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From page 303... ...
Schreinemachers' (2000) examination of cancer mortality over the years 1980-1989 in four northern wheat-producing states used wheat acreage per county as a surrogate for exposure to chlorophenoxy herbicides (including 2,4-D)
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From page 304... ...
This analysis found no association between a categorical measure of serum dioxin levels and the incidence of melanoma or skin cancers in general. Ranch Hand veterans in the low-exposure category had a higher incidence of skin cancers and melanoma than those in the background- or high-exposure categories, but the difference was not statistically significant.
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From page 305... ...
exposures and acknowledges the efforts of AFHS researchers in this area. Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides (2,4-D, 2,4,5T and its contaminant TCDD, cacodylic acid, and picloram)
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From page 306... ...
TABLE 7-13 Selected Epidemiologic Studies Melanoma Mortality Reference Study Population Exposed Casesa Estimated Risk (95% CI) a OCCUPATIONAL New Studies Hooiveld et al., 1998 Dutch production workers Studies Reviewed in Update 1998 Hertzman et al., 1997 Sawmill workers Kogevinas et al., 1997 IARC cohort Workers exposed to TCDD (or higher-chlorinated dioxins)
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From page 307... ...
a OCCUPATIONAL Studies Reviewed in Update 1998 Hertzman et al., 1997 Sawmill workers Svensson et al., 1995 Swedish fishermen East coast West coast Studies Reviewed in Update 1996 Lynge, 1993 Danish male production workers Studies Reviewed in VAO Ronco et al., 1992 Danish self-employed farmers 38 1.0 (0.7-1.2)
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From page 308... ...
It found that there was inadequate or insufficient information to determine whether an association existed between exposure to the herbicides used in Vietnam or the contaminant dioxin and basal or squamous cell cancers. Tables 715 and 7-16 provide summaries of the results of the studies underlying these findings and a list of reports that contain details of the research.
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From page 309... ...
Analyses that separated BCC by location generated inconsistent but generally nonsignificant results, as might be expected from the small number of cases examined. There were relatively few squamous cell carcinomas among Ranch Hands (20 of 805)
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From page 310... ...
This analysis found no association between a categorical measure of serum dioxin levels and the incidence of basal or squamous cell carcinomas. Ranch Hand veterans in the low-exposure category had a higher incidence of skin cancers and melanoma than those in the background- or high-exposure categories or the comparison group, but the differences were not statistically significant.
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From page 311... ...
311 li, Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides (2,4-D, 2,4,5T and its contaminant TCDD, cacodylic acid, and picloram) and basal or squamous cell cancers.
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From page 312... ...
Skin Cancer Morbidity Estimated Exposed Risk Reference Study Population Casesa (95% CI) a OCCUPATIONAL Studies Reviewed in Update 1998 Zhong and Rafnsson, 1996 Icelandic pesticide users Svensson et al., 1995 Swedish fishermen East coast West coast Studies Reviewed in VAO Ronco et al., 1992 Danish self-employed farmers 493 ENVIRONMENTAL Studies Reviewed in Update 1998 Gallagher et al., 1996 Alberta, Canada, residents squamous cell carcinoma All herbicide exposure Low herbicide exposure 5 2.8 (0.9-6.6)
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From page 313... ...
Squamous cell carcinoma (SCC) Australian Vietnam veterans male Australian Vietnam veterans female Air Force Ranch Hand veterans Basal cell carcinoma Squamous cell carcinoma 121 1.2 (0.9-1.6)
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From page 314... ...
In the age groups that characterize most Vietnam veterans, the incidence for whites is slightly higher than that for African Americans. Risk factors other than aging include a personal or family history of breast cancer and certain characteristics of one's reproductive history (specifically, early onset of menarche, late onset of menopause, and either no pregnancies or first full-term pregnancy after 30 years of age)
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From page 315... ...
No elevations in mortality from breast cancer were found. Among residents of zone A, the area of highest contamination, the relative risk for females was 0.6 (0.1-3.9, 1 death observed)
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From page 316... ...
This is in excess of the 5 cases that were expected and beyond the expected range of 2-11 cases. Although there is a statistically significant excess of breast cancer in this study population, there are non-war-related risk factors that may be confounding the findings.
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From page 317... ...
Overall, the data are not conclusive in supporting a protective effect or an association between exposure to the herbicides of concern in this report and the risk of breast cancer. The significance of these findings for Vietnam era veterans who may have experienced different patterns of organochlorine exposure, reflecting the herbicides of concern, is not known.
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From page 318... ...
Increased Risk of Disease Among Vietnam Veterans There are no data on which to base a conclusion concerning whether Vietnam veterans may or may not be at increased risk for breast cancer due to exposure to herbicides or TCDD. TABLE 7-17 Selected Epidemiologic Studies Breast Cancer Reference Study Population Exposed Casesa Estimated Risk (95% CI)
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From page 319... ...
Lynge, 1985 Danish production workers 13 0.9 Wiklund, 1983 Swedish agricultural workers 444 0.8 (0.7_0.9) b ENVIRONMENTAL New Studies Bertazzi et al., 2001 Seveso residents 20-year follow-up Zone A females 2 0.8 (0.2-3.1' Zone B females 12 0.7 (0.4-1.3)
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From page 320... ...
Diet, a family history of the disease, and breast cancer are among the risk factors for endometrial and ovarian cancers.
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From page 321... ...
Summary of VAO, Update 1996, and Update 1998 The committee responsible for VAO found there to be inadequate or insufficient information to determine whether an association existed between exposure to herbicides used in Vietnam or the contaminant dioxin and female reproductive cancers. Additional information available to the committees responsible for Update 1996 and Update 1998 did not change this finding.
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From page 322... ...
The latest update also indicates 2 cases of uterine cancer in zone B where 3.8 were expected, for a relative risk of 0.5 (0.1-2.1~.
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From page 323... ...
Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides (2,4-D, 2,4,5T and its contaminant TCDD, cacodylic acid, and picloram) and uterine, ovarian, or cervical cancers.
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From page 324... ...
veterans of the Vietnam era may shed further light on this issue. TABLE 7-18 Selected Epidemiologic Studies Cancers of the Cervix Reference Study Population Exposed Casesa Estimated Risk (95% CI)
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From page 325... ...
TABLE 7-20 Selected Epidemiologic Studies Ovarian Cancer Estimated Exposed Risk Reference Study Population Casesa (95% CI) a OCCUPATIONAL Studies Reviewed in Update 1998 Kogevinas et al., 1997 IARC cohort Studies Reviewed in Update 1996 Kogevinas et al., 1993 IARC cohort Lynge, 1993 Danish female production workers 7 Studies Reviewed in VAO Ronco et al., 1992 Donna et al., 1984 o 1 0.7 3.2 Danish farmers Self-employed farmers Family workers Employees Female residents near Alessandria, Italy 12 104 5 18 0.9 0.8 0.5 4.4 (1.9-16.1)
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From page 326... ...
Answer to question: Since your first day of service in Vietnam, have you been told by a doctor that you have ovarian cancer? PROSTATE CANCER Background According to American Cancer Society estimates, 180,400 new cases of prostate cancer (ICD 9 185)
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From page 327... ...
Update of the Scientific Literature Since Update 1998, a few new published papers have reported data on prostate cancer mortality or incidence in populations with possible or documented exposures to TCDD. Several of these involved occupational exposures (Dich and Wiklund, 1998; Fleming et al., l999a,b; Steenland et al., 1999; Sharma-Wagner et al., 2000)
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From page 328... ...
The authors also note a current theory that postulates vitamin D exposure to be protective for prostate cancer; if true, those working outdoors might be at lower risk than the general population, which spends a considerable portion of time indoors, even in Florida. A second study focused on pesticide appliers, but examined prostate cancer incidence.
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From page 329... ...
The Air Force Health Study 1997 follow-up of Ranch Hand personnel did not reveal any excess of prostate cancer cases (AFHS, 2000~. Ranch Hand personnel did not have higher risks than the comparison cohort, nor was the risk of prostate cancer seen to rise with increasing blood dioxin levels.
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From page 330... ...
The true association would then be stronger than that observed. The excess prostate cancer incidence in the study from Sweden, the strong association in the study of Florida's pesticide appliers, and the reference of Fleming et al.
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From page 331... ...
Conclusions Strength of Evidence in Epidemiologic Studies There is limited/suggestive evidence of an association between exposure to herbicides (2,4-D, 2,4,5-T and its contaminant TCDD, cacodylic acid, and picloram) and prostate cancer.
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From page 332... ...
Continued follow-up of the Ranch Hand cohort for both biologic monitoring of PSA levels and verification of prostate cancer incidence will be important for determining prostate cancer risk. The statistically significant elevated prostate cancer SMRs for Australian male Vietnam veterans is suggestive that U.S.
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From page 333... ...
farmers in 23 states Whites Nonwhites Dutch production workers 3 Monsanto 2,4-D production workers 9 Canadian farmers, age 45-69 years, no employees, or custom workers, sprayed 2250 acres Danish self-employed farm workers Dutch herbicide appliers NIOSH cohort 20-year latency, 1-year exposure German production workers IARC cohort BASF production workers USDA forest conservationists Soil conservationists Paper and pulp workers Paper and pulp workers 5 0.8 (0.3-1.8)
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From page 334... ...
Bertazzi et al., 1989a Seveso residents 10-year follow-up Zones A, B R males 19 1.6 (1.0-2.7 Bertazzi et al., 1989b Seveso residents 10-year follow-up Zone B males 3 2.2 (0.7-6.9 VIETNAM VETERANS New Studies AFHS, 2000 AIHW, 1999 Air Force Ranch Hand veterans 26 0.7 (0.4-1.3)
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From page 335... ...
Answer to question: Since your first day of service in Vietnam, have you been told by a doctor that you have prostate cancer? TESTICULAR CANCER Background The American Cancer Society estimates that 6,900 men will be diagnosed with testicular cancer (ICD 9 186.0-186.9)
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From page 336... ...
Table 7-22 provides summaries of the results of the studies underlying these findings and a list of reports that contain details of the research. Update of the Scientific Literature Occupational Studies A case-control study of occupational risk factors for testicular cancer was conducted by Hardell et al.
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From page 337... ...
Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides (2,4-D, 2,4,5T and its contaminant TCDD, cacodylic acid, and picloram) and testicular cancer.
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From page 338... ...
a OCCUPATIONAL New Studies Fleming et al., 1999 Florida pesticide appliers Hardell et al., 1998 Workers exposed to herbicides Studies Reviewed in Update 1998 Hertzman et al., 1997 British Columbia sawmill workers Mortality Incidence [ARC cohort Pentachlorophenol production workers Kogevinas et al., 1997 Ramlow et al., 1996 Studies Reviewed in Update 1996 Blair et al., 1993 U.S. farmers in 23 states White males Nonwhite males Studies Reviewed in VAO Ronco et al., 1992 Saracci et al., 1991 Bond et al., 1988 Coggon et al., 1986 Wiklund, 1983 ENVIRONMENTAL New Studies Bertazzi et al., 2001 Bertazzi et al., 1998 Danish self-employed farm workers IARC cohort Dow 2,4-D production workers British MCPA production workers Swedish agricultural workers Seveso residents 20-year follow-up Zone A males Zone B males Seveso residents 15-year follow-up Zone B males Zone R males Studies Reviewed in Update 1998 Zhong and Rafnsson, 1996 Icelandic pesticide users Studies Reviewed in Update 1996 Bertazzi et al., 1993 Seveso residents 10-year follow-up, morbidity Zone B males Zone R males Studies Reviewed in VAO Pesatori et al., 1992 4 23 2.5 (1.6-3.7)
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From page 339... ...
is the most common of the genitourinary tract cancers. According to American Cancer Society estimates, 38,300 men and 14,900 women will be diagnosed with this cancer in the United States in 2000, and 8,100 men and 4,100 women will die from the disease (ACS, 2000a)
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From page 340... ...
(1998) conducted a retrospective cohort study of 549 exposed and 482 unexposed male Dutch production and contract workers exposed to
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From page 341... ...
examination of cancer mortality over the years 1980-1989 in four northern wheat-producing states combined the analysis of bladder cancer with other cancers of the urinary organs (ICD 9 189.3~. This analysis, which used wheat acreage per county as a surrogate for exposure to chlorophenoxy herbicides (including 2,4-D)
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From page 342... ...
The committee encourages further follow-up on the AFHS and occupational cohorts and urges researchers to separate kidney and bladder cancers in their analyses and to fully control for exposure to other potential or known bladder carcinogens in the occupational setting. Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides (2,4-D, 2,4,5T and its contaminant TCDD, cacodylic acid, and picloram)
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From page 343... ...
Increased Risk of Disease Among Vietnam Veterans Although limited data available on Vietnam veterans do suggest they may be at an elevated risk for urinary bladder cancer, the estimated risk ratios are very unstable. Further studies of Ranch Hand Air Force veterans may clarify whether exposures incurred in Vietnam, or dioxin in particular, are associated with altered risks for bladder cancer.
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From page 344... ...
11 0.8 3 1.6 274 0.9 (NS) Henneberger et al., 1989 Alavanja et al., 1988 Bond et al., 1988 Coggon et al., 1986 Robinson et al., 1986 Lynge, 1985 Blair et al., 1983 Burmeister, 1981 ENVIRONMENTAL New Studies Bertazzi et al., 2001 Schreinemachers, 2000 Bertazzi et al., 1998 Seveso residents 20-year follow-up Zone A males Zone B males Rural or farm residents of Minnesota, Montana, North Dakota, and South Dakota Males counties with wheat acreage 23,000-110,999 Males counties with wheat acreage >111,000 Females counties with wheat acreage 23,000-110,999 Females counties with wheat acreage >111,000 Seveso residents 15-year follow-up Zone A males Zone B males Zone R males Zone R females Studies Reviewed in Update 1998 Gambini et al., 1997 Italian rice growers Ott and Zober, 1996 - ~ Svensson et al., 1995 Swedish fishermen, mortality East coast West coast BASE cleanup workers Swedish fishermen, incidence East coast West coast Studies Reviewed in VAO Pesatori et al., 1992 Seveso residents Zones A, B males Zones A, B females Finnish community exposed to chlorophenols Lampi et al., 1992 1.7 (0.2-12.0)
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From page 345... ...
Although the diseases of these organs have different characteristics and may have different risk factors, there is logic to this aggregation because these structures are all exposed to filterable compounds, such as polycyclic aromatic hydrocarbons, that appear in urine. The American Cancer Society estimates that 18,800 men and 12,400 women will be diagnosed with renal cancers (ICD 9 189.0, 189.1)
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From page 346... ...
(1998) conducted a retrospective cohort study of 549 exposed and 482 unexposed male Dutch production and contract workers exposed to phenoxy herbicides, chlorophenols, and contaminants between 1950 and 1976.
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From page 347... ...
Cigarette smoking also covaried with the indicators of herbicide exposure used by AFHS researchers, confounding their analyses. The elevated incidence observed in the AFHS cohort was seen in Ranch Hands in the low-dioxin category but not the high-dioxin category, which would not be expected if an association existed between exposure and the outcome.
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From page 348... ...
chemical production workers 13 1.6 (0.8-2.7) Hooiveld et al., 1998 Male Dutch production and contract workers Total cohort kidney cancer Total cohort "urinary organs" Accidentally exposed subcohort Studies Reviewed in Update 1998 Kogevinas et al., 1997 IARC cohort Workers exposed to TCDD (or higher-chlorinated dioxins)
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From page 349... ...
farmers in 23 states White males Nonwhite males White females Nonwhite females 522 1.1 (1.0-1.2) 30 6 6 Danish male self-employed farm workers 141 NIOSH cohort 8 German production workers 3 IARC cohort 11 USDA forest conservationists Soil conservationists Paper and pulp workers USDA agricultural extension agents Dow 2,4-D production workers Paper and pulp workers British MCPA production workers Danish male production workers Swedish agricultural workers Florida pesticide appliers Farmers in Iowa Seveso residents 20-year follow-up Zone B males Zone B females Rural or farm residents of Minnesota, Montana, North Dakota, and South Dakota Males counties with wheat acreage 23,000-110,999 Males counties with wheat acreage >111,000 Females counties with wheat acreage 23,000-110,999 Females counties with wheat acreage >111,000 Studies Reviewed in Update 1996 Bertazzi et al., 1993 Seveso residents 10-year follow-up, morbidity Zone R males Zone R females Studies Reviewed in VAO Pesatori et al., 1992 6 5 3 775 1 178 0.6 (p < .05)
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From page 350... ...
Several other potential factors have been examined, but the American Cancer Society notes that the majority of brain cancers are not associated with any known risk factors.
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From page 351... ...
retrospective cohort study of Dutch production and contract workers exposed to phenoxy herbicides, chlorophenols, and contaminants found no deaths due to brain cancer between 1950 and 1976 in the cohort of 1,031 males. In the update of the industrial cohort exposed to dioxins known as the NIOSH cohort, Steenland et al.
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From page 352... ...
Synthesis rl~he studies reviewed for the first time in this report, like those reviewed in earlier Veterans and Agent Orange reports, found small numbers of cases of brain tumors and risk estimates fairly evenly distributed around 1.0. Conclusions Strength of Evidence in Epidemiologic Studies Based on its evaluation of the epidemiologic evidence reviewed in this and previous Veterans and Agent Orange reports, the committee finds there is limited/suggestive evidence of no association between exposure to herbicides (2,4D, 2,4,5-T and its contaminant TCDD, cacodylic acid, and picloram)
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From page 353... ...
a OCCUPATIONAL New Studies Steenland et al., 1999 U.S. chemical production workers 8 Studies Reviewed in Update 1998 Gambini et al., 1997 Italian rice growers Kogevinas et al., 1997 IARC cohort Becher et al., 1996 Ramlow et al., 1996 Studies Reviewed in Update 1996 Asp et al., 1994 Finnish herbicide appliers Dean, 1994 Irish farmers and farm workers Workers exposed to TCDD (or higher-chlorinated dioxins)
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From page 354... ...
4 0.7 5 2.0 111 1.1 (NS) Men and women in the Milan, Italy, area British MCPA production workers Paper and pulp workers Danish male production workers Florida pesticide appliers Farmers in Iowa ENVIRONMENTAL New Studies Bertazzi et al., 2001 Schreinemachers, 2000 Bertazzi et al., 1998 Seveso residents 20-year follow-up Zone B males Zone B females Rural or farm residents of Minnesota, Montana, North Dakota, and South Dakota Males counties with wheat acreage 23,000-110,999 Males counties with wheat acreage >111,000 Females counties with wheat acreage 23,000-110,999 Females counties with wheat acreage >111,000 Seveso residents 15-year follow-up Zone B males Zone B females Zone R males Zone R females Studies Reviewed in Update 1998 Bertazzi et al., 1997 Seveso residents 15-year follow-up Zone B males Zone B females Zone R males Svensson et al., 1995 Zone R females Swedish fishermen, mortality East coast West coast Swedish fishermen, incidence East coast West coast Studies Reviewed in Update 1996 Bertazzi et al., 1993 Seveso residents 10-year follow-up, morbidity Zone R males Zone R females Studies Reviewed in VAO Pesatori et al., 1992 Seveso residents Zones A, B females 0.5 (0.1-3.5)
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From page 355... ...
R males Zones A, B R females Air Force Ranch Hand veterans 1 Australian military Vietnam veterans Australian national service Vietnam veterans Dalager and Kang, 1997 Army Chemical Corps veterans Studies Reviewed in Update 1996 Dalager et al., 1995 Women Vietnam veterans Visintainer et al., 1995 Michigan Vietnam veterans Boyle et al., 1987 Vietnam Experience Study Studies Reviewed in VAO Thomas and Kang, 1990 Army Chemical Corps Vietnam veterans Breslin et al., 1988 Army Vietnam veterans Marine Vietnam veterans Anderson et al., 1986a Anderson et al., 1986b Lawrence et al., 1985 NOTE: MCPA = methyl-4-chlorophenoxyacetic acid; NS = not significant; USDA = United States Department of Agriculture.
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From page 356... ...
(1998) conducted a retrospective cohort study of 549 exposed and 482 unexposed male Dutch production and contract workers exposed to phenoxy herbicides, chlorophenols, and contaminants between 1950 and 1976.
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From page 357... ...
Schreinemachers (2000) examined cancer mortality in white males and females over the years 1980-1989 in four northern wheat-producing states, using wheat acreage per county as a surrogate for exposure to chlorophenoxy herbicides (including 2,4-D)
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From page 358... ...
The evidence regarding association is drawn from occupational and other studies in which subjects were exposed to a variety of herbicides and herbicide components. Biologic Plausibility No animal studies have found an increased incidence of non-Hodgkin's lymphoma.
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From page 359... ...
a Reference Study Population Exposed Casesa OCCUPATIONAL New Studies Steenland et al., 1999 Hooiveld et al., 1998 workers Studies Reviewed in Update 1998 Gambini et al., 1997 Italian rice growers Keller-Byrne et al., 1997 Kogevinas et al., 1997 IARC cohort U.S. chemical production workers 12 Male Dutch production and contract Becher et al., 1996 Nanni et al., 1996 Ramlow et al., 1996 Amadori et al., 1995 Studies Reviewed in Update 1996 Kogevinas et al., 1995 IARC cohort diagnosed with NHL Exposed to 2,4,5-T Exposed to TCDD Asp et al., 1994 Finnish herbicide appliers Dean, 1994 Irish farmers and farm workers Males Females Male residents of northern Sweden Exposure to phenoxy herbicides Exposure to chlorophenols Hardell et al., 1994 1.1 (0.6-1.9)
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From page 360... ...
Danish male production workers 10 1.7 (0.5-4~5) Swedish NHL patients Exposure to phenoxy herbicides Occupation as a lumberjack Females in eastern Nebraska farms IARC cohort Workers exposed to any phenoxy herbicide or chlorophenol 2.3 (0.7-7.2)
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From page 361... ...
Pearce et al., 1985 Male residents of New Zealand Agricultural occupations, ages 20-64 1.4 (0.9-2.0) Burmeister et al., 1983 Iowa residents Farmers 1.3 Farmers in 33 counties with highest herbicide use Born before 1890 3.4 Born 1890-1900 2.2 Born after 1900 1.3 Riihimiki et al., 1982 Finnish herbicide appliers 0 Wiklund, 1983 Swedish agricultural workers 1.1 (()
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From page 362... ...
VIETNAM VETERANS New Studies AFHS, 2000 Air Force Ranch Hand veterans 1 0.2 (0.0-2.6) AIHW, 1999 Australian Vietnam veterans 62 48 expected (34-62)
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From page 363... ...
Michalek et al., 1990 Air Force Ranch Hand veteran mortality O Wolfe et al., 1990 Air Force Ranch Hand veteran morbidity 1 Breslin et al., 1988 Army Vietnam veterans 108 0.8 (0.6-1.0) Marine Vietnam veterans 35 2.1 (1.2-3.8)
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From page 364... ...
is distinct from NHL in its cell of origin, demographics, and genetics. According to American Cancer Society estimates, 4,200 men and 3,200 women will be diagnosed with the disease in the United States in 2000, and 700 men and an equal number of women will die from it (ACS, 2000a)
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From page 365... ...
Occupational Studies Update of the Scientific Literature Hooiveld and colleagues' (1998) retrospective cohort study of 549 exposed and 482 unexposed male Dutch production and contract workers exposed to phenoxy herbicides, chlorophenols, and contaminants between 1950 and 1976 reported 1 death from HD in the cohorts under examination (SMR = 3.2, 0.117.6)
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From page 366... ...
Schreinemachers (2000) examined cancer mortality in white males and females over the years 1980-1989 in four northern wheat-producing states, using wheat acreage per county as a surrogate for exposure to chlorophenoxy herbicides (including 2,4-D)
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From page 367... ...
Conclusions Strength of Evidence in Epidemiologic Studies Based on its evaluation of the epidemiologic evidence reviewed in this and previous Veterans and Agent Orange reports, the committee finds there is sufficient evidence to conclude that an association exists between exposure to herbicides (2,4-D, 2,4,5-T and its contaminant TCDD, cacodylic acid, and picloram) and Hodgkin's disease.
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From page 368... ...
farmers from 23 states white males 56 IARC cohort females Swedish NHL patients Exposure to phenoxy herbicides 5 IARC cohort 3 Swedish Cancer Registry patients Male sawmill workers Male farmers Male forestry workers Male horticulture workers Danish and Italian farm workers 1 10 2.2 97 1.2 35 1.2 11 1.2 1.7 (0.2-6.0)
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From page 369... ...
Exposed to low-grade chlorophenols 5 2.4 (0.9-6.5) Riihimaki et al., 1982 Finnish herbicide appliers 0 Wiklund, 1983 Swedish agricultural workers 226 1.0 (0.9-1.2)
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From page 370... ...
7 1.1 (0.4-2.6) Michalek et al., l99C Wolfe et al., 1990 Air Force Ranch Hand veteran mortality O Breslin et al., 1988 Army Vietnam veterans compared to Vietnam era Army veterans 92 1.2 (0.7-1.9)
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From page 371... ...
The American Cancer Society estimates that 7,300 men and 6,300 women in the U.S. will be diagnosed with this disease in 2000 and that 5,800 men and 5,400 women will die from it (ACS, 2000a)
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From page 372... ...
retrospective cohort study of 549 exposed and 482 unexposed male Dutch production and contract workers exposed to phenoxy herbicides, chlorophenols, and contaminants between 1950 and 1976 did not identify any deaths from MM in the cohorts under examination. In an update and expansion of cohorts involved in the NIOSH study, Steenland et al.
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From page 373... ...
examined cancer mortality over the years 19801989 in four northern wheat-producing states, using wheat acreage per county as a surrogate for exposure to chlorophenoxy herbicides (including 2,4-D)
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From page 374... ...
chemical production workers 10 2.1 (1.0-3.8) Hooiveld et al., 1998 Dutch chemical production workers 0 Studies Reviewed in Update 1998 Gambini et al., 1997 Italian rice growers Kogevinas et al., 1997 IARC cohort o Workers exposed to TCDD (or higher-chlorinated dioxins)
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From page 375... ...
Born 1890-1900 Born after 1900 Finnish herbicide appliers Seveso residents 20-year follow-up Zone B males Zone B females Rural or farm residents of Minnesota, Montana, North Dakota, and South Dakota Males counties with wheat acreage 23,000-110,999 Males counties with wheat acreage >111,000 1.2 (0.8-1.7)
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From page 376... ...
2 0.5 (0.0-17.1) NOTE: USDA = United States Department of Agriculture.
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From page 377... ...
Risk factors associated with an increased risk of AML include high doses of ionizing radiation, occupational exposure to benzene, and some medications used in cancer chemotherapy (melphalan, for example)
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From page 378... ...
, plasma cell, monocytic, and acute and chronic erythremia and erythroleukemia. Summary of VAO, Update 1996, and Update 1998 The committee responsible for VAO found there to be inadequate or insufficient information to determine whether an association existed between exposure to herbicides used in Vietnam or the contaminant dioxin and leukemia.
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From page 379... ...
retrospective cohort study of 549 exposed and 482 unexposed male Dutch production and contract workers exposed to phenoxy herbicides, chlorophenols, and contaminants between 1950 and 1976 reported 1 death attributed to leukemia (SMR = 1.0, 0.0-5.7~. A study of cancer incidence among workers in three paper production plants in Denmark by Rix et al.
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From page 380... ...
Synthesis Studies of leukemia reviewed for the first time in this report continue the pattern of those examined in previous Veterans and Agent Orange reports, with risks fairly evenly distributed around the null. Conclusions Strength of Evidence in Epidemiologic Studies There is no information contained in the research reviewed for this report to change the conclusion that there is inadequate or insufficient evidence to determine whether an association exists between exposure to herbicides (2,4-D,2,4,5T and its contaminant TCDD, cacodylic acid, and picloram)
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From page 381... ...
Kogevinas et al., 1993 Female herbicide-spraying and production workers 1 Studies Reviewed in VAO Bueno de Mesquita et al., Dutch production workers 1993 Workers exposed to phenoxy herbicides 2 2.2 (0.3-7.9) Hansen et al., 1992 Danish gardeners All gardeners CLL 6 2.5 (0.9-5.5)
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From page 382... ...
Wigle et al., 1990 Saskatchewan farmers 138 0.9 (0.7-1.01 Zober et al., 1990 BASE production workers Second additional cohort 1 5.2 (0.4-63.1) Alavanja et al., 1988 USDA agricultural extension agents 1.9 (1.0-3.5)
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From page 383... ...
1 2.5 (0.2-27.0) VIETNAM VETERANS New Studies AFHS, 2000 Air Force Ranch Hand veterans 2 0.7 (0.1-5.0)
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From page 384... ...
Typically, at least one high-quality study indicates a positive association, though most frequently several studies provide positive results, but the results of other studies may be inconsistent. Health Outcomes with Inadequate/Insufficient Evidence to Determine Whether an Association Exists The scientific data for many of the cancers reviewed by the committee were inadequate or insufficient to determine whether an association exists.
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From page 385... ...
, nasal and nasopharyngeal cancer, bone cancer, skin cancers (including basal cell carcinoma, squamous cell carcinoma, and nonmelanocytic skin cancers) , breast cancer, cancers of the female reproductive system (including cervix, endometrium, and ovaries)
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From page 386... ...
386 VETERANS AND AGENT ORANGE: UPDATE2000 notably the thyroid gland, skin, and lungs. Studies have demonstrated an increased incidence of liver cancer following TCDD exposure, but only after other adverse changes in the liver were observed.
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From page 387... ...
Information is emerging that there might be animal data supporting a carcinogenic effect of cacodylic acid, but these data alone are not sufficient to draw conclusions on the carcinogenicity of this compound in humans. Considerable uncertainty remains about how to apply this information to the evaluation of potential health effects of herbicides or dioxin exposure in Vietnam veterans.
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From page 388... ...
American Journal of Industrial Medicine 26:243-253.
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From page 389... ...
1996. Cancer mortality in German male workers exposed to phenoxy herbicides and dioxins [see comments]
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From page 390... ...
1993. Occupational exposure to phenoxy herbicides and chlorophenols and cancer mortality in the Netherlands.
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From page 391... ...
American Journal of Industrial Medicine 31:719-726. Dalager NA, Kang HK, Burt VL, Weatherbee L
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From page 392... ...
1997. Interpreting recent trends in prostate cancer incidence and mortality.
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From page 393... ...
1997. Mortality and cancer incidence among sawmill workers exposed to chlorophenate wood preservatives.
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From page 394... ...
1992. Cancer mortality from soft-tissue sarcoma and malignant lymphomas in an international cohort of workers exposed to chlorophenoxy herbicides and chlorophenols.
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From page 395... ...
1993. Farming and prostate cancer mortality.
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From page 396... ...
1991. Cancer mortality in workers exposed to chlorophenoxy herbicides and chlorophenols.
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From page 397... ...
American Journal of Industrial Medicine 3:179-189. Thomas TL.
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From page 398... ...
. British Journal of Industrial Medicine 49:815-816.
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Key Terms
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