Women in the formaldehyde industry: their exposures and their jobs

Several studies have examined disease risks for women separately from risks for men, but few have examined exposure differences. This report used data from an epidemiological study of formaldehyde workers to compare formaldehyde exposures between men and women. Exposures were estimated from historical monitoring results, walk-through workplace surveys, interviews with long-term workers, and reviews of historical records. The mean of the exposures in the first job, the last job, and the highest exposed job were calculated by gender. Differences were found when all subjects were included in the analysis (men having higher exposures, on average, than women), but when nonexposed subjects were removed (40% of women, 6% of men), differences were minor. There was a substantial difference in the estimated peak exposure between men and women that decreased, but remained, when only exposed subjects were included. Evaluation of exposures in 1940 to 1945, 1965, and 1979 found that women had a higher average exposure than men in 1940 to 1945, but this pattern was reversed in 1965. By 1979, the average difference between the two genders had disappeared. A comparison of cumulative exposure found that exposed women had half the total exposure of exposed men. More men than women were exposed to other chemicals. Women tended to predominate in clerical, laboratory, assembly, finishing, inspecting, packing, and shipping jobs.

Cohort mortality and nested case-control study of lung cancer among structural pest control workers in Florida (United States)

A previous report on the mortality of this cohort of Florida (United States) pest control workers found the risk of lung cancer was positively associated with the number of years licensed. An additional follow-up (1977-82) of this male cohort confirmed the excess (SMR = 1.4) and the rising risk with increasing number of years licensed (SMR = 2.2 among workers employed more than 20 years). A nested case-control study was undertaken to determine the effects of smoking and the type of pesticide exposure on lung cancer risk. Occupational histories and other data were obtained on 65 deceased lung cancer cases, 122 deceased controls, and 172 living controls. Interviews were conducted with next-of-kin regardless of the vital status of the subject. Odds ratios (OR) were adjusted by age and smoking. Adjustments for diet and other occupations had no effect on risk estimates and were not included in the final model. Using information from licensing records, ORs for lung cancer were greater for workers first licensed before age 40 (OR = 2.4, 95 percent confidence interval [CI] = 1.0-5.9 with deceased controls) and increased from 1.4 (CI = 0.7-3.0) for subjects licensed 10-19 years to 2.1 (CI = 0.8-5.5) for subjects licensed 20 or more years. Using living controls, an association with duration of employment was observed when years of licensure were lagged five years, but was not observed in unlagged analyses. Using information from the questionnaire, the risk of lung cancer was greater among those who worked as pest control operators than non-pest control workers.(ABSTRACT TRUNCATED AT 250 WORDS)

Extended mortality follow-up among men and women in a U.S. furniture workers union

The addition of 5 years of follow-up and over 411,000 person-years of observation to a cohort of 34,081 men and women employed in U.S. furniture and other related industries allowed the investigation of mortality patterns among women and minority races in addition to white men. A significant excess of pleural mesotheliomas occurred among white men (standardized mortality ratio [SMR] = 3.7, 95% confidence interval [CI] = 1.2-8.7) but could not be linked to a particular type of furniture manufacturing. SMRs for myeloid leukemia and chronic nephritis were elevated among white men employed in the wood furniture industry but were not statistically significant. Males in the black/other race categories in wood furniture plants showed nonsignificant mortality excesses for infectious diseases and cancers of the prostate and colon and rectum. Among white women employed in wood furniture plants, mortality was elevated for cancers of the pancreas and lung during the most recent follow-up period. In metal furniture plants, mortality was raised among men in both race groups for kidney cancer (black/other SMR = 8.0, 95% CI = 1.6-23.2; white SMR = 2.1, 95% CI = 0.4-6.2) and diabetes mellitus (black/other SMR = 2.2, 95% CI = 0.6-5.6; white SMR = 1.8, 95% CI = 0.7-3.9). Stomach cancer mortality was significantly elevated (SMR = 3.3, 95% CI = 1.3-6.8) among white men in metal furniture plants and was of the same magnitude over both the previous and the most recent follow-up periods. Among those working with textiles, SMRs were significantly elevated for leukemia (SMR = 6.1, 95% CI = 1.2-7.8) and cancers of the colon and rectum (SMR = 3.2, 95% CI = 1.3-4.5) for white women. Lung cancer mortality was increased for white men and women in textile operations, but SMRs were not statistically significant. SMRs for a number of other causes of death that were elevated at the end of the earlier follow-up period were not increased during the new follow-up period.

[A retrospective evaluation of exposure to dichloromethane by using a job-exposure matrix]

The impact of three features of a job-exposure matrix has been tested in a case-control study that evaluated the association of occupational exposure to dichloromethane and astrocytic brain cancer. These features were probability of exposure, an exposure assessment by decades, and the use of a more specific coding system of industries and occupations. The introduction of each feature had a striking effect on the estimate of relative risk. The odds ratio increased from 1.47 with none of these features, to 2.47 with high probability of exposure, to 4.15 with high probability of exposure and the specific coding system, to 6.08 with all features combined. These results indicate that job-exposure matrices efficacy in reducing the degree of exposure misclassification may be greatly improved by the introduction of these features.

Cancer mortality among jewelry workers

Mortality was investigated for the years 1950-1980 for 1,009 male members of a New York jewelry workers union, and for the years 1984-1989 among 919 men and 605 women identified as jewelry workers on death certificates from 24 states. Malignant neoplasms were excessive for male union members (proportional mortality ratio [PMR] = 1.17; 95% confidence interval [CI]: 1.02-1.33) and female jeweler deaths from the 24 states (PMR = 1.24; 95% CI: 1.07-1.42). Deaths due to nonmalignant causes were not unusual, except for excesses, in union males, of the circulatory system (PMR = 1.10; 95% CI: 1.02-1.19), including arteriosclerotic heart disease (PMR = 1.25; 95% CI: 1.14-1.37) and rheumatic heart disease (PMR = 3.02; 95% CI: 1.94-4.50). Cancers of the digestive tract were proportionally elevated among union males (proportional cancer mortality rate [PMR] = 1.13; 95% CI: 0.89-1.41) and among deaths from the 24 states (PCMR = 1.22; 95% CI: 1.01-1.47). For the 24 states, excesses for digestive cancer were found for both males (PCMR = 1.19; 95% CI: 0.90-1.54) and females (PCMR = 1.26; 95% CI: 0.96-1.62). Regarding specific sites in the digestive tract, colon cancer excesses were found in union males (PCMR = 1.53: 95% CI: 1.05-2.15), and for men (PCMR = 1.27; 95% CI: 0.82-1.88) and women (PCMR = 1.36; 95% CI: 0.92-3.27) in 24 states.(ABSTRACT TRUNCATED AT 250 WORDS)

Cancer among migrant and seasonal farmworkers: an epidemiologic review and research agenda

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.

The role of agricultural pesticide use in the development of non-Hodgkin's lymphoma in women

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.

Occupational physical activity, socioeconomic status, and risks of 15 cancer sites in Turkey

A multiple-site case-control study of 15 cancers (stomach; colon; rectum; larynx; lung; melanoma; skin; female breast; male breast; cervix; ovary; uterus; prostate; testis; and bladder) was conducted to evaluate their association with occupational physical activity and socioeconomic status (SES). A hospital-based study population (3,486 male cases and 379 female cases, and 2,127 male and 244 female controls) was established in an oncological treatment center in Istanbul, Turkey, from 1979-84. Assessment of physical activity and SES was based on job titles held by the study subjects. Two measures of physical activity were developed based on energy expenditure and 'sitting time' during working hours. Observed risks were adjusted for age, smoking, and SES. Elevated risks were observed among workers who held sedentary jobs for cancers of the colon (odds ratio [OR] = 1.6), rectum (OR = 1.3), melanoma (OR = 1.9), male breast (OR = 1.4), prostate (OR = 5.0), and ovary (OR = 2.0). Cancers of the cervix and uterus showed significantly decreasing risks with decreased activity. Risks of cancers of the colon, rectum, larynx, ovary, and melanoma were enhanced after risks for physical activity indices were adjusted for SES, while the associations between physical activity and cancers of the prostate, cervix, and uterus were weakened after SES adjustment. Risks of melanoma rose significantly with both activity indices after SES adjustment.(ABSTRACT TRUNCATED AT 250 WORDS)

Bridging the gap between research and clinical practice: a collaborative approach

In nursing, a gap sometimes exists between research and practice. This paper discusses how a group of 11 nurses successfully bridged this gap. The group was composed of nurses from a large teaching hospital, a regional outpatient cancer center, and a university. The result of the group's work over a two-year period was an externally funded research proposal. This paper discusses the strategies that led to the group's success and provides specific recommendations for nurses who want to form similar groups.

Cancer and other causes of death among male and female farmers from twenty-three states

Occupation and industry codes on death certificates from 23 states for 1984-1988 were used to evaluate mortality risks among white and nonwhite, male and female farmers. Proportionate mortality and proportionate cancer mortality ratios were calculated using deaths among nonfarmers from the same states to generate expected numbers. Among farmers there were 119,648 deaths among white men, 2,400 among white women, 11,446 among nonwhite men, and 2,066 among nonwhite women. Deficits occurred in all race-sex groups for infective and parasitic diseases, all cancer combined, lung cancer, liver cancer, diseases of the nervous system, multiple sclerosis, hypertension, and emphysema. As reported in other studies, white male farmers had excesses of cancer of the lymphatic and hematopoietic system, lip, eye, brain, and prostate. Excesses of cancers of the pancreas, kidney, bone, and thyroid were new findings. Regional patterns were evident, particularly among white men. Significant excesses for accidents, vascular lesions of the central nervous system (CNS), and cancers of the prostate tended to occur in most geographic regions, while excesses for mechanical suffocation, non-Hodgkin's lymphoma, and cancers of the lip, brain, and the lymphatic and hematopoietic system were limited to the Central states. Increases among nonwhite men were similar to those in white men for some causes of death (vascular lesions of the CNS and cancers of the pancreas and prostate), but were absent for others (lymphatic and hematopoietic system, lip, eye, kidney, and brain). Women (white and nonwhite) had excesses for vascular lesions of the CNS, disease of the genitourinary system (white women only), and cancers of the stomach and cervix (nonwhite women only). Cancer of the buccal cavity and pharynx was slightly elevated among women, and white women had nonsignificant excesses of multiple myeloma and leukemia. Excesses for leukemia and non-Hodgkin's lymphoma occurred among white men and women, but not among nonwhites. Excesses for several types of accidental deaths were seen among all race-sex groups.

Validity of exposure in one job as a surrogate for exposure in a cohort study

Frequently, information pertaining to only one job is available or used to evaluate risk estimates of disease in occupational epidemiologic research. The amount of misclassification that such a practice could create has not, however, been examined. We used data from a mortality study of workers employed in 10 formaldehyde-producing or -using plants to address how closely several parameters of exposure based on the first, longest, or last job held in a company compared with those based on the worker's entire employment history at the plant. The best predictor for cumulative formaldehyde exposure at the plant was the longest job at that plant, with a correlation coefficient (r) of 0.70. The correlation with average exposure over the worker's employment was 0.77 for the first job and 0.74 for the longest and last jobs. Peak exposures and highest exposure levels experienced in the plant were more closely related to the first job (r = 0.72 and r = 0.74). The highest correlation with any of the measures was never with the last job. Variation between plants for each of these comparisons, however, was wide. These findings indicate that the use of a single job as a surrogate for exposure received at a particular worksite can result in different degrees of misclassification for different exposure measures. Even though the correlations were generally high, the associated misclassification of exposure could lead to a substantial underestimation of the relative risks in some situations. In this report two hypothetical examples show what effect the misclassification rates could have on estimates of disease risks.

Role of the herbicide atrazine in the development of non-Hodgkin's lymphoma

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.

Imagery effects on the performance of skilled and novice soccer players

The purpose of this study was to investigate the effect of an imagery training programme on the performance of a soccer task by skilled and novice players. An initial assessment of performance on the soccer task was undertaken, and then 22 skilled and 22 novice players were equally and randomly assigned to either a control or an experimental group. The experimental group was given an imagery training programme consisting of both visual and kinaesthetic imagery, and in which both internal and external imagery perspectives were included. The programme lasted 6 weeks, with the subjects attending bi-weekly sessions of approximately 15 min each. The control group developed a competitive strategy that was totally unrelated to the performance task. Similar to the experimental group, the controls did this over a 6-week period, attending bi-weekly sessions of 15 min duration. Two performance measures were recorded--response time (i.e. the time to complete the soccer task) and performance accuracy (i.e. errors in performing the soccer task recorded in the form of time penalties). Performance on the post-test as measured by response time revealed a significant improvement for both the skilled and novice players in the imagery group. The control group failed to show any such improvement. No effects were found for performance accuracy.

Agricultural exposures and cancer trends in developed countries

Recent increases have been reported in industrial countries for several sites of cancer. The causes of these increases remain unknown. Efforts should proceed to identify those occupational groups with increases in the same sites, as these may indicate relevant exposures. Two analyses were undertaken: trends in cancer mortality in industrial countries were reviewed to identify recently increasing sites and summaries were compiled of studies on farmers which have shown increased risks for these same sites of cancer. Using data provided by the World Health Organization, age-specific rates were developed for a number of sites of cancer from 1968 to 1986. Trends in the ratio of male to female cancer mortality were also assessed for several of these countries. Based on a literature review by the National Cancer Institute, patterns of cancer in farmers reported in 20 studies from 8 countries are summarized, weighting each study by its size to create combined relative risks. In industrial countries, rates of cancer mortality increased for a number of sites, including melanoma, prostate, non-Hodgkin's lymphoma, multiple myeloma, breast, brain, and kidney cancer. The ratio of male to female cancer mortality (for all sites of cancer excluding lung) has generally increased in several countries during this same time period. Many of the same sites that have increased in the general population have also been found to be increasing in farmers. Significant excesses occurred for Hodgkin's disease, multiple myeloma, leukemia, skin melanomas, and cancers of the lip, stomach, and prostate. Nonsignificant increases in risk were also noted for non-Hodgkin's lymphoma and cancers of connective tissue and brain in many surveys.(ABSTRACT TRUNCATED AT 250 WORDS)

Pesticide exposures and multiple myeloma in Iowa men

A population-based case-control study of 173 White men with multiple myeloma (MM) and 650 controls was conducted in Iowa (United States), an area with a large farming population, to evaluate the association between MM, agricultural risk factors, and exposure to individual pesticides. A slight nonsignificantly elevated risk for MM was seen among farmers (odds ratio [OR] = 1.2, 95 percent confidence interval [CI] = 0.8-1.7). Although slight excesses were observed, there were no significant associations between MM and handling either classes of pesticides or specific pesticides. Thus, this study found little evidence to suggest an association between risk of MM and farming or pesticides.

Evaluation of risks for non-Hodgkin's lymphoma by occupation and industry exposures from a case-control study

The etiology of non-Hodgkin's lymphoma (NHL) is not well understood. To develop hypotheses on causes of this tumor, data from a population-based case-control interview study of 1,867 white men (622 cases and 1,245 controls) in Iowa and Minnesota conducted during 1980-1983 were examined. Subjects, or their next of kin, were interviewed to obtain information on agricultural exposures, work history, medical conditions, and family history. This analysis focuses on risks of NHL by occupation, by industry, and by selected exposures. Although many comparisons were made, few significant associations were observed. Small numbers and limitations in exposure assessment, however, would tend to reduce opportunities to detect associations. The strongest finding was with various occupations that work in metals and metal products. The analysis by exposure estimates also uncovered a significant association with metals, but risks did not increase with estimated intensity of exposure. Slightly elevated risks were also noted among persons employed as painters and construction workers, agricultural and forestry workers, printers and typesetters, funeral directors and embalmers, and dry cleaners. Although the overall risks for benzene and other solvents were small, they increased slightly with level of assigned exposure. Although some associations may be due to chance, several of these occupations and industries have been linked to lymphoma in other investigations and deserve further attention.

Patterns of pesticide use among farmers: implications for epidemiologic research

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.

Hair dye use and multiple myeloma in white men

In recent reports, multiple myeloma has been linked to use of hair coloring products containing mutagenic and carcinogenic chemicals. A population-based case-control study in Iowa of 173 White men with multiple myeloma and 650 controls obtained information on hair dye use. Risk of multiple myeloma was significantly elevated (OR = 1.9) among hair dye users and was greatest among those using hair dyes at least once a month for a year or more (OR = 4.3). These data, along with results from other studies, suggest that use of hair dyes contributes to the development of multiple myeloma.

Occupational physical activity and colon cancer risk in Turkey

A case-control study of 107 colon cancer cases and 486 controls from an oncological clinic in Istanbul was conducted to examine the association between occupational physical activity and colon cancer in Turkey, where incidence of this disease is low. Only two of the four activity measures showed evidence of an increased colon cancer risk for sedentary jobs (time spent sitting OR = 1.5 and occupational energy expenditure OR = 1.6); neither was statistically significant. Subjects below age 55 showed higher risk associated with sedentary jobs than did the older age group, probably due to their adoption of a more western lifestyle, including dietary habits, less activity, and other factors that may interact to increase the risk of colon cancer.

Occupational risk factors for multiple myeloma among Danish men

A large population-based case-control study evaluated occupational exposures in 1,098 Danish males diagnosed with multiple myeloma from 1970 to 1984 and in 4,169 age- and gender-matched controls alive at the time of case-diagnosis. Industrial histories were obtained from the Supplementary Pension Fund which, since 1964, has recorded employments of adult Danes; occupation came from subjects' most recent tax records. Four industrial hygienists created a job-exposure matrix for 47 substances based on 15,000 unique industry/occupation combinations in subjects' histories. Risk of myeloma was significantly elevated among road and railroad workers, precision metalworkers, and workers in the transportation and communication industries. Risk increased significantly with duration of employment in: production of synthetic yarns, plastic packaging, and miscellaneous chemical compounds; fabricating structural metal and stationary tanks; body factories; electrical plants; and retail sale of paint and wallpaper. Risks of myeloma were elevated, though statistically nonsignificantly, in all categories of exposure to gasoline and engine exhausts. Risks rose with likelihood and duration of exposure to phthalates, and were statistically significant and nearly fivefold with probable exposure to vinyl chloride for five or more years. After adjusting for multiple exposures and disregarding exposures within 10 years of diagnosis (or selection as a control), probable exposure to vinyl chloride was associated with increased risk of myeloma, which rose to fivefold with longer exposure. Associations with gasoline, engine exhausts, and phthalates persisted, but were inconsistent with duration and probability of exposure. Previously reported associations with agriculture were not confirmed by these data.

Regulation of even-skipped stripe 2 in the Drosophila embryo

In an effort to determine how crude gradients of transcriptional activators and repressors specify sharp stripes of gene expression in the early embryo, we have conducted a detailed study of even-skipped (eve) stripe 2. A combination of promoter fusions and P-transformation assays were used to show that a 480 bp region of the eve promoter is both necessary and sufficient to direct a stripe of LacZ expression within the limits of the endogenous eve stripe 2. The maternal morphogen bicoid (bcd) and the gap proteins hunchback (hb), Kruppel (Kr) and giant (gt) all bind with high affinity to closely linked sites within this small promoter element. Activation appears to depend on cooperative interactions among bcd and hb proteins, since disrupting single binding sites cause catastrophic reductions in expression. gt is directly involved in the formation of the anterior border, although additional repressors may participate in this process. Forming the posterior border of the stripe involves a delicate balance between limiting amounts of the bcd activator and the Kr repressor. We propose that the clustering of activator and repressor binding sites in the stripe 2 element is required to bring these weakly interacting regulatory factors into close apposition so that they can function both cooperatively and synergistically to control transcription.

Comments on occupational and environmental factors in the origin of non-Hodgkin's lymphoma

The review of the literature regarding non-Hodgkin's lymphoma and occupational and environmental factors presented at this workshop suggested associations with viruses, solvents, and hair dyes. A population-based case-control study among men from Iowa and Minnesota notes similar associations. Workers engaged in metal working, hair care, painting, and dry cleaning experienced nonsignificant excesses. Risks from specific exposures showed some variation by histological type. Both follicular and diffuse non-Hodgkin's lymphoma were associated with benzene. The diffuse type was linked to solvents other than benzene and formaldehyde, while the follicular was excessive among workers exposed to oils and greases.