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Chlorinated aliphatic hydrocarbons (CAHs) were evaluated as potential risk factors for astrocytic brain tumors. Job-exposure matrices for six individual CAHs and for the general class of organic solvents were applied to data from a case-control study of brain cancer among white men. The matrices indicated whether the CAHs were likely to have been used in each industry and occupation by decade (1920-1980), and provided estimates of probability and intensity of exposure for "exposed" industries and occupations. Cumulative exposure indices were calculated for each subject. Associations of astrocytic brain cancer were observed with likely exposure to carbon tetrachloride, methylene chloride, tetrachloroethylene, and trichloroethylene, but were strongest for methylene chloride. Exposure to chloroform or methyl chloroform showed little indication of an association with brain cancer. Risk of astrocytic brain tumors increased with probability and average intensity of exposure, and with duration of employment in jobs considered exposed to methylene chloride, but not with a cumulative exposure score. These trends could not be explained by exposures to the other solvents.

A survey of published epidemiologic studies from eight journals during 1971 to 1990 was conducted to assess the proportion and characteristics of occupational cancer studies that have included women and minorities. A total of 1233 reports included 562 (46%) with subjects limited to white men. The remaining 671 (54%) had subjects from other race-gender groups. Thirty-five percent included white women, but only 14% presented any analyses of white women specifically and only 7% presented more than five risk estimates. The proportions with analyses of nonwhite women (any = 2%; detailed = 1%) or men (any = 7%; detailed = 3%) were also small. Studies with detailed analyses of women and minorities tended to use weaker methodologies (ie, proportionate mortality or cross-sectional design) than the studies of white men and were less able to provide convincing data on the occupational cancer risks of women and minorities.

A cohort mortality study was conducted among 9028 (3042 women, 5986 men) workers potentially exposed to chlorinated naphthalenes (chloracnegens structurally similar to dioxins) and asbestos in the manufacture of Navy cable during World War II. Based on mortality through December 31, 1985, standardized mortality ratios (SMRs) for all cancers was 1.03 in women (95% confidence interval [CI] = 0.9 to 1.17) and 1.18 in men (95% CI = 1.10 to 1.26). There were no significant elevations in causes of death hypothesized a prior to be associated with chlorinated naphthalene exposure (malignant neoplasms [MN] of connective tissue, liver, and lymphatic and hematopoietic organs). An excess of MN of the connective tissue was suggested for workers with over 1 year of exposure and 25 years of latency (SMR = 3.54; 95% CI = 0.97 to 9.07). Among cancer sites not hypothesized to be related a priori, three showed concordant excesses among both genders (MN of stomach; rectum; and trachea, bronchus, and lung). No significant elevations occurred in hormonally related cancers among women. Cancer mortality among 460 individuals with chloracne (431 men, 29 women) was similar to that of the entire cohort, although the chloracne subcohort showed significant excesses in two rare causes of death (MN of esophagus, SMR = 3.26; "benign and unspecified neoplasms," SMR = 4.93). Use of county referent rates decreased SMRs for stomach, rectal, and buccal cavity cancer, suggesting a role for nonoccupational risk factors. It is difficult to draw conclusions about carcinogenicity of chlorinated naphthalenes because of study limitations, most importantly, concomitant asbestos exposure and the relatively short duration of exposure to chlorinated naphthalenes among most of the cohort.

There are an estimated three million hired migrant and seasonal farmworkers in the United States. Adults and children may be exposed to mutagenic and potentially carcinogenic pesticides during planting, weeding, thinning, and harvesting crops. Field conditions that provide little opportunity to wash skin or clothing to minimize pesticide absorption may intensify exposure. Little is known, however, about the occurrence of cancer in migrant or seasonal farmworkers. Most cancer epidemiologic research on agricultural populations has focussed on farm owner/operators. The few studies that have evaluated cancer in farmworkers suggest that, like farm owner/operators, they may be experiencing excesses of multiple myeloma and cancers of the stomach, prostate, and testis. A few studies suggest that the farmworkers may differ from farmers by experiencing excesses of cancers of the buccal cavity and pharynx, lung, and liver. Cervical cancer was elevated in female farmworkers in one study. Descriptive data and etiologic research on cancer among farmworkers and family members are urgently needed. Feasibility evaluations, however, should precede etiologic investigations because of possible difficulties in studying this population of workers. Issues that need to be evaluated include assessing where and when farmworkers and family members are diagnosed and/or treated for malignancies, the ability of farmworkers to provide histories of crops, locations, and years worked and living conditions, the ability of agricultural experts to determine likely pesticide exposures based on such farmworkers' histories, the ability to obtain information on potential confounding factors, the ability to recontact or determine vital status of specific farmworkers over time, the suitability of conducting studies in home-base vs. upstream counties, and the ability to study agriculturally related malignancies in persons who have left farm work before the disease occurs.

Non-Hodgkin's lymphoma has been found to be associated with agricultural pesticide use in men, but little is known about the risk in women. In a recent population-based, case-control study conducted in eastern Nebraska, no increased risk of non-Hodgkin's lymphoma was found in women who had ever lived or worked on a farm (odds ratio [OR] = 1.0). Neither the use of insecticides (OR = 0.8) nor herbicides (OR = 0.7) on the farm was associated with non-Hodgkin's lymphoma; however, the number of women who mixed or applied pesticides was small, particularly in comparison to men on farms. Small nonsignificant associations were observed among the women who personally handled insecticides (OR = 1.3) or herbicides (OR = 1.2). Women who personally handled organophosphate insecticides had a significant 4.5-fold increased risk of non-Hodgkin's lymphoma. Use of chlorinated hydrocarbon insecticides was associated with an OR of 1.6; however, the use on dairy cattle was associated with a 3-fold increased risk. Pesticide-related risks were greater among women with a family history of cancer, particularly a history of lymphatic or hematopoietic cancer among first-degree relatives.

Atrazine is the most commonly used herbicide in the United States and is a wide-spread groundwater contaminant in the Midwest. The role of atrazine in the development of human non-Hodgkin's lymphoma (NHL) was investigated in three case-referent studies conducted in four midwestern states in the United States. A total of 993 white men with NHL and 2918 population-based referents were interviewed concerning their agricultural practices. When the results of the three studies were combined, atrazine use was associated with an odds ratio of 1.4 [95% confidence interval (95% CI) 1.1-1.8, 130 cases, 249 referents) for NHL. However, adjustments for the use of 2,4-dichlorophenoxyacetic acid and organophosphate insecticides reduced the apparent association between NHL and atrazine in all but one state and reduced the associations for the long-term and frequent users in Nebraska. Detailed analyses suggested that there was little or no increase in the risk of NHL attributable to the agricultural use of atrazine.

Risk factors for superficial and invasive bladder cancer were examined in a case-control study of 470 cases identified in 1967-68 in the Brockton and Boston Standard Metropolitan Areas (MA, United States) and of 500 population-based controls. Histologic specimens were reviewed and classified as superficial or invasive, following a standardized protocol. The tobacco-associated risk for superficial bladder cancer was odds ratio (OR) = 2.6 (95 percent confidence interval [CI] = 1.7-4.1) and the risk for invasive bladder cancer was OR = 1.7 (CI = 1.1-2.5). For subjects less than 60 years of age, the risks were greater for invasive tumors (OR = 4.3, CI = 1.2-15) than for superficial tumors (OR = 2.0, CI = 0.9-4.2), but this pattern for tobacco use was not found in older subjects. A strong trend of increased risk with increased amount of cigarettes smoked was shown only for invasive bladder tumors. No clear pattern of excess risk for invasive bladder tumors was seen for age at first use and years since last use of tobacco. The risk associated with occupational exposure to aromatic amine bladder carcinogens was OR = 1.7 (CI = 0.8-3.3) for superficial and OR = 1.5 (CI = 0.8-3.0) for invasive bladder cancer. For subjects less than 60 years of age, the risks were greater for invasive (OR = 12.0, CI = 2.1-65) than for superficial tumors (OR = 4.3, CI = 0.8-24), but this pattern for occupational exposure was not found in older subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidemiologic studies of farmers have linked pesticides with certain cancers. Information on exposures from many of these studies was obtained by interview of farmers or their next-of-kin. The reliability and validity of data on pesticide use obtained by recall, often years after the event, have been questioned. Pesticide use, however, is an integral component in most agricultural operations, and the farmers' knowledge and recall of chemicals used may be better than for many other occupations. Contrary to general belief, many farmers typically use only a few pesticides during their lifetimes and make only a few applications per year. Data from U.S. Department of Agriculture surveys indicate that herbicides are applied to wheat, corn, soybeans, and cotton and that application of insecticides to corn averages two or fewer times per year. In epidemiologic studies at the National Cancer Institute, the proportion of farmers ever reporting lifetime use of five or more different chemicals was 7% for insecticides and 20% for herbicides. Surrogate respondents have often been used in epidemiologic studies of cancer; they are able to recall pesticide use with less detail than the farmers themselves. The pesticides reported by surrogates were the same as reported by subjects themselves, but with less frequency. Comparison of reporting by cases and controls provided no evidence of case-response (differential) bias; thus, inaccurate recall of pesticide use by subjects or surrogates would tend to diminish risk estimates and dilute exposure-response gradients.

The incidence of non-Hodgkin's lymphoma (NHL) has increased over 50% in the last 15 years. This paper reviews the possible role of pesticides in this increase. While small increases in risk of NHL among farmers have been observed in general occupational surveys, recent studies focusing on specific pesticides have observed much larger risks. Frequent use of phenoxyacetic acid herbicides, in particular, 2,4-dichlorophenoxyacetic acid, has been associated with 2- to 8-fold increases of NHL in studies conducted in Sweden, Kansas, Nebraska, Canada, and elsewhere. Canine malignant lymphoma has also been associated with dog owner use of 2,4-dichlorophenoxyacetic acid and commercial lawn pesticide treatments. There are much fewer data linking NHL to other types of pesticides, but triazine herbicides, organophosphate insecticides, fungicides, and fumigants have also been associated with increased risk of NHL. Pesticide exposures are not limited to agricultural populations but are widespread in the general population through use on lawns, golf courses, rights-of-way, and elsewhere. Since the use of pesticides, particularly phenoxy herbicides, has increased dramatically preceding and during the time period in which the incidence of NHL has increased, they could have contributed to the rising incidence of NHL.

Occupational cancer mortality was evaluated among approximately three million female pensioners from urban areas of the former USSR. In 1970, these women experienced 14,918 cancer deaths. Occupational data were obtained from death certificates and the 1970 USSR National Population Census. Thirty-five occupational groups, including nine predominantly professional or office-work groups and 26 groups involving physical labor, were evaluated. The expected mortality rates were based on the urban female population of the USSR in 1970. Data for all cancer sites combined, and cancers of the esophagus, stomach, colon, rectum, lung, breast, cervix, and hematopoietic system are presented. Among all female pensioners, there were significant increases of all cancers combined (rate ratio [RR] = 1.05), and cancers of the breast (RR = 1.3), cervix (RR = 1.3), and the hematopoietic system (RR = 1.2), and a significant deficit of cancer of the esophagus (RR = 0.8). Many well-established associations between cancer and occupation among men were observed among the study group of female pensioners, such as stomach and lung cancer among miners, and hematopoietic malignancies among scientists and physicians. Other associations, to be investigated further, also were observed, such as excess lung cancer among waitresses. The peak employment period for this cohort of women was during World War II and the postwar period, when Soviet women outnumbered men almost two-to-one. Consequently, many of the women held jobs that are typically held by men. Thus, this study provides valuable information on occupational risks to women that may be relevant in other countries where women increasingly are being employed in jobs traditionally held by men.

A report of an increased risk of soft tissue sarcoma (STS) among users of smokeless tobacco led us to evaluate this association and the role of other types of tobacco in a prospective cohort mortality-study of United States veterans. A total of 248,046 veterans provided tobacco-use histories on a mail questionnaire in 1954 or 1957. Data on subsequent tobacco use were not collected. By 1980, 119 deaths from STS had occurred among the cohort members. Veterans who had ever chewed tobacco or used snuff had a nonsignificant 40 percent excess of STS (95 percent confidence interval [CI] = 0.8-2.6; 21 deaths) in comparison with veterans who had never used any tobacco products. Risk was limited to former users (relative risk [RR] = 1.5) with no excess seen among current users (RR = 0.9). Frequent former users had higher risk (RR = 1.9) than infrequent users (RR = 1.3). Risk was slightly higher in persons who started using smokeless tobacco at younger ages, but did not increase with duration of use or with late age at cessation of use. Most veterans who used chewing tobacco or snuff also used some other form of tobacco. No STS deaths occurred among the 2,308 veterans who used smokeless tobacco only. An unexpected finding of the study was the significant excess of STS deaths among cigarette smokers (RR = 1.8, CI = 1.1-2.9). Risk was higher among ex-smokers (RR = 2.2) than among current smokers (RR = 1.5) and was not related to number of cigarettes per day, age started smoking, duration, or pack-years.(ABSTRACT TRUNCATED AT 250 WORDS)

The relationship between the use of cigarettes and other tobacco products and the risk of multiple myeloma was examined in a cohort of nearly 250,000 American veterans followed prospectively for 26 years. Compared with men who had never tobacco, the risk of death from myeloma was not increased among current (relative risk [RR] = 0.9, 95 percent confidence interval [CI] = 0.8-1.2) or former (RR = 1.0, CI = 0.8-1.3) cigarette smokers, nor among users of chewing tobacco or snuff (RR = 1.0, CI = 0.4-2.3). Risk was only slightly and nonsignificantly increased among pipe or cigar smokers (RR = 1.2, CI = 0.9-1.5). There was no indication of increasing risk with amount of tobacco used or earlier age at first use. With over 90 percent power to detect a 30 percent increased risk of this tumor occurring among current cigarette smokers, this study provides the strongest evidence to date against an association of cigarette smoking with multiple myeloma.

Epidemiologic studies of cancer and exposure to herbicides have shown puzzling inconsistencies. Exposure-response gradients have been reported for non-Hodgkin's lymphoma in Sweden and Kansas, but no significant associations were seen in New Zealand or Washington State. Subjects in these studies were categorized by exposure using information obtained primarily by interview. A number of questions can be raised regarding the reliability and validity of such an exposure assessment. We examined procedures used to assess pesticide exposures in case-control studies of cancer to evaluate their limitations and their probable effects on risk estimates. Except for case recall bias, problems of misclassification in these studies would tend to bias risk estimates toward the null and dilute exposure-response gradients. These problems are, therefore, unlikely explanations for the positive associations between cancer and herbicide use noted in some investigations. A tendency for false-negative findings, however, is not reassuring, and improvements in exposure assessment are needed if epidemiologic investigations are to continue to provide reliable information on the relationships of cancer and pesticide exposure.

A case-control study of lung cancer was conducted to evaluate the relationship between lung cancer histologic types and occupation, adjusted for smoking. A total of 4,431 white male cases and 11,326 cancer controls, diagnosed between 1980 and 1985, were identified through the Missouri Cancer Registry. For all histologic types combined, excess risk was observed among many a priori suspected high-risk occupations. Lung cancer was elevated among men employed as insulators (odds ratio [OR] = 6.0; 95% confidence interval [CI] = 0.7, 137.8), carpenters (OR = 1.3; 95% CI = 1.0, 1.7), painters, plasterers, and wallpaper hangers (OR = 2.0; 95% CI = 1.2,3.3), structural metal workers (OR = 1.9; 95% CI = 0.6,6.0), mechanics and repairers (OR = 1.3; 95% CI = 1.0,1.7), motor vehicle drivers (OR = 1.5; 95% CI = 1.2,1.8), police and firefighters (OR = 1.6; 95% CI = 1.1,2.3), and food service personnel (OR = 1.8; 95% CI = 1.0,3.5). A deficit of lung cancer was observed among farmers (OR = 0.9; 95% CI = 0.7,1.0). Adenocarcinoma of the lung was elevated among carpenters (OR = 1.6; 95% CI = 1.0,2.5) and cabinet and furniture makers (OR = 2.0; 95% CI = 0.4,8.1), which is interesting because of the previous reports of excess adenocarcinoma of the nasal cavity associated with wood dust exposure. Adenocarcinomas were also elevated among plumbers (OR = 2.0; 95% CI = 1.0,3.8) and printers (OR = 1.8; 95% CI = 0.7,4.2). Electricians were at slightly increased risk for adenocarcinoma (OR = 1.5; 95% CI = 0.7,2.8) and "other" or mixed cell types of lung cancer (OR = 1.5; 95% CI = 0.8,2.9) but at decreased risk for small cell (OR = 0.8; 95% CI = 0.3,2.0) and squamous cell (OR = 0.8; 95% CI = 0.4,1.6) tumors. Among welders, adenocarcinoma (OR = 1.7; 95% CI = 0.7,3.8) and squamous cell (OR = 1.7; 95% CI = 0.9,3.3) cancers were elevated, but small cell and "other" lung cancers were not. Despite the limitations of the Cancer Registry data, some interesting associations were observed that merit further study, particularly the association between lung adenocarcinoma and occupational exposure to wood and wood dust.

A population-based case-referent study in Kansas examined the relationship between exposure to insecticides and the development of soft-tissue sarcoma (STS) and Hodgkin's disease (HD). Data from telephone interviews for 133 STS cases, 121 HD cases, and 948 referents indicated that STS was associated with use of insecticides on animals, but not on crops. HD was not significantly associated with either use. STS risk was higher among the farmers who themselves mixed or applied insecticides to animals than among farmers who did not. Farmers who failed to use any protective equipment to reduce insecticide exposure were at a significantly elevated risk of STS. Risk rose with early calendar year of first use. The excess risk appeared to be primarily among fibrous and myomatous sarcomas with little association seen for lipomatous or other STS neoplasms. Myomatous sarcomas increased significantly with duration and time since first use of insecticides on animals. If the reported association between STS and insecticides is causal, the data suggest that exposure to the agent(s) responsible may have been reduced in the mid-1950s or the agent(s) have an average latency period for STS of at least 20 years.

Cause specific mortality was investigated among 36,622 members of a national furniture workers' union who were first employed in unionised shops between 1946 and 1962. Overall mortality for each race and sex group was less than expected when compared with United States death rates (white men SMR = 0.8, black men SMR = 0.7, white women SMR = 0.8, black women SMR = 0.5); however, raised risks were observed among white men employed in specific types of furniture industries and followed up for 20 or more years after first employment. Lymphatic and haematopoietic cancers were significantly raised (SMR = 1.8) among wood furniture workers followed up for at least 20 years due to excess deaths from leukaemia (SMR = 2.0) and non-Hodgkin's lymphoma (SMR = 2.0). Mortality from acute myeloid leukaemia was particularly high in this group (SMR = 4.7) based on six observed cases. Metal furniture workers followed up for at least 20 years experienced a significant excess of all cancers combined (SMR = 1.6), with non-significant increases in cancers of the lung, stomach, and colorectum. This group also had non-significant excesses of liver cirrhosis, arteriosclerotic heart disease, and cerebrovascular disease. Nasal cancer was not found to be significantly raised in this cohort, though the average follow up period may not have been sufficient to detect an excess risk for this uncommon tumour.

The relationship between bladder cancer employment in the chemical industry was assessed in a study of 2,982 incident cases and 5,782 population controls. There were 190 cases and 369 controls who had ever been employed in the chemical industry [odds ratio (OR) = 1.0; 95% confidence interval (CI) = 0.8, 1.2]. Employment in the production of organic chemicals was associated with a 1.3-fold increased risk among men (95% CI = 0.8, 2.1). Risk increased with duration of employment, reaching an OR of 2.4 for 20 or more years (chi for trend = 1.57; P = .06). Women who had worked in the plastics industry had a 3.3-fold increased bladder cancer risk. Within the plastics and rubber industry, increased risks for bladder cancer were found for men in mixing, filtering, grinding, and other dusty operations (OR = 4.6; 95% CI = 1.0, 20.4) and men in heat-associated operations (OR = 2.8; 95% CI = 0.5, 15.3). A 1.4-fold risk among men in agricultural chemicals was attributable to risks in the pesticides subdivision (OR = 2.3; 95% CI = 0.6, 8.2). Men performing dusty operations (i.e., mixing, filtering, sifting, grinding, and crushing) in any industry had an OR of 1.4 (95% CI = 0.8, 2.7). Despite the large number of study subjects, few statistically significant findings were observed and should be evaluated with consideration of the large number of comparisons made in the analysis. The statistical power of case-control studies to detect risks associated with particular occupational exposures is limited by the small proportion of the population employed in any specific occupation or industry.

Data were analyzed from a case-control interview study of malignant mesothelioma in Louisiana, which gathered information on usual diet and on lifetime occupational exposure to asbestos. Thirty-seven patients with malignant mesothelioma of the pleura (n = 32) or peritoneum (n = 5) were matched to controls according to age, sex, race, and factors related to case ascertainment (hospital and date of diagnosis, or parish and date of death). Twenty-one of the 37 cases were judged by masked occupational review to have been exposed to asbestos (57%), compared to seven of 37 controls (19%). Seven additional cases and 10 additional controls had occupational histories suggestive of asbestos exposure. With regard to usual diet before illness, cases reported less frequent consumption of homegrown produce (p = 0.005), cruciferous vegetables (p = 0.005), and all vegetables combined (p = 0.09) than did the controls. An estimate of usual carotene intake was also significantly lower in cases (p = 0.03). Dose-dependent reductions in risk were seen with increasing consumption of vegetables, especially cruciferous vegetables (p for trend = 0.013). These associations were not explained by differences in asbestos exposure as measured by the occupational review. The results indicate that consumption of vegetables or some vegetable-related constituent may have a protective effect on developing mesothelioma.