Task Exposure Matrix Research Articles

Occupational exposure to disinfectants and asthma control in US nurses.

Disinfectant use has been associated with adverse respiratory effects among healthcare workers. However, the specific harmful agents have not been elucidated. We examined the association between occupational exposure to disinfectants and asthma control in the Nurses' Health Study II, a large cohort of female nurses.Nurses with asthma were invited in 2014 to complete two questionnaires on their current occupation and asthma (response rate 80%). Asthma control was defined by the Asthma Control Test (ACT). Exposure to major disinfectants was evaluated by a job-task-exposure matrix (JTEM).Analyses included 4102 nurses with asthma (mean age 58 years). Asthma control was poor (ACT score 16-19) in 12% of nurses and very poor (ACT score ≤15) in 6% of nurses. Use of disinfectants to clean medical instruments (19% exposed) was associated with poorly (OR 1.37; 95% CI 1.05-1.79) and very poorly (OR 1.88, 95% CI 1.38-2.56) controlled asthma (ptrend=0.004, after adjustment for potential confounders). Using JTEM estimates, exposure to formaldehyde, glutaraldehyde, hypochlorite bleach, hydrogen peroxide and enzymatic cleaners was associated with poor asthma control (all ptrend<0.05); exposure to quaternary ammonium compounds and alcohol was not.Use of several disinfectants was associated with poor asthma control. Our findings suggest targets for future efforts to prevent worsening of asthma control in healthcare workers.

Maternal occupational pesticide exposure and risk of congenital heart defects in the National Birth Defects Prevention Study.

Congenital heart defects (CHDs) are common birth defects, affecting approximately 1% of live births. Pesticide exposure has been suggested as an etiologic factor for CHDs, but previous results were inconsistent. We examined maternal occupational exposure to fungicides, insecticides, and herbicides for 3328 infants with CHDs and 2988 unaffected control infants of employed mothers using data for 1997 through 2002 births from the National Birth Defects Prevention Study, a population-based multisite case-control study. Potential pesticide exposure from 1 month before conception through the first trimester of pregnancy was assigned by an expert-guided task-exposure matrix and job history details self-reported by mothers. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression. Maternal occupational exposure to pesticides was not associated with CHDs overall. In examining specific CHD subtypes compared with controls, some novel associations were observed with higher estimated pesticide exposure: insecticides only and secundum atrial septal defect (OR = 1.8; 95% CI, 1.3-2.7, 40 exposed cases); both insecticides and herbicides and hypoplastic left heart syndrome (OR = 5.1; 95% CI, 1.7-15.3, 4 exposed cases), as well as pulmonary valve stenosis (OR = 3.6; 95% CI, 1.3-10.1, 5 exposed cases); and insecticides, herbicides, and fungicides and tetralogy of Fallot (TOF) (OR = 2.2; 95% CI, 1.2-4.0, 13 exposed cases). Broad pesticide exposure categories were not associated with CHDs overall, but examining specific CHD subtypes revealed some increased odds ratios. These results highlight the importance of examining specific CHDs separately. Because of multiple comparisons, additional work is needed to verify these associations.

0150 Respiratory effects of an exposure to wheat dust among grain workers and farmers: a longitudinal study

ObjectivesAgriculture is considered one of the occupations most at risk of acute or chronic respiratory problems. The aim of our study was to determine from which level of exposure to...

Occupational Trichloroethylene Exposure and Cervical Pathology: A Case–Control Study

Trichloroethylene (TCE) is suspected of association with elevated risk of cervical cancer. A case-control study was performed in a geographical area in which occupational TCE exposure is high. The study objective was to analyze the correlation between occupational TCE exposure and cervical cancer (including precancerous conditions). Case and control subjects were recruited by gynecologists. General and occupational data were collected by telephonic interviews. An industrial hygienist assessed occupational TCE exposure on a task-exposure matrix. Analysis focused on occupational TCE exposure at various levels and on cumulative dose. Multivariate analysis was performed to take account of the various risk factors. In total, 67 case and 67 age-matched control subjects were included. Mean age was 36 years in both groups. Five of the possible general risk factors correlated significantly with cervical dysplasia or cancer: number of partners, history of genital or anal wart, interval between first period and first sexual relation, parity, and body mass index, the last three showing inverse correlation. Elevated risk was found in women who had had jobs as manual workers according to the PCS French classification (professions and socioprofessional categories), and production and related workers according to ISCO classification (International Standard Classification of Occupations), with odds ratios (ORs), adjusted on general and medical risk factors, of 7.68 [95% confidence interval (CI): 1.39-42.54] and 7.48 (1.30-43.24), respectively, among skilled service sector workers; the adjusted OR was close to significance, at 4.67 (95% CI: 0.92-23.67). No occupational sectors were significantly associated with elevated risk. In all, 17 (25.4%) case and 15 (22.4%) control subjects were exposed to TCE: raw OR = 1.17 (95% CI: 0.54-2.52), adjusted OR = 1.51 (95% CI: 0.42-5.41). There was no significant correlation between cumulative dose and exposure time. The study found no significantly increased risk of cervical dysplasia or cancer associated with occupational TCE exposure.

Biomechanical risk factors for knee disorders in Carpenters

Years of occupational health research in construction indicated that more information was needed to help bring proper attention to specific suffering by certain construction trades. In this study, knee disorders in Carpenter specialties were examined by observation and expert opinion in order to rank specific factors of exposure. Ergonomic profiles for an exhaustive taxonomy of their work were found. A comparison of validated methods of exposure assessment was useful in identifying key factors of exposure, and to strengthen the epidemiologic link between the task-exposure matrix and outcomes of knee disorder.

Is potroom asthma due more to sulphur dioxide than fluoride? An inception cohort study in the Australian aluminium industry

ObjectivesAlthough an asthma-like syndrome has been recognised in aluminium smelter workers for over 70 years, the causal agent has been difficult to identify.MethodsAn inception cohort study was conducted at two...

Development of a Task-Exposure Matrix (TEM) for Pesticide Use (TEMPEST)

Pesticides have been associated with increased risks for a range of conditions including Parkinson's disease, but identifying the agents responsible has proven challenging. Improved pesticide exposure estimates would increase the power of epidemiological studies to detect such an association if one exists. Categories of pesticide use were identified from the tasks reported in a previous community-based case-control study in Scotland. Typical pesticides used in each task in each decade were identified from published scientific and grey literature and from expert interviews, with the number of potential agents collapsed into 10 groups of pesticides. A pesticide usage database was then created, using the task list and the typical pesticide groups employed in those tasks across seven decades spanning the period 1945-2005. Information about the method of application and concentration of pesticides used in these tasks was then incorporated into the database. A list was generated of 81 tasks involving pesticide exposure in Scotland covering seven decades producing a total of 846 task per pesticide per decade combinations. A Task-Exposure Matrix for PESTicides (TEMPEST) was produced by two occupational hygienists who quantified the likely probability and intensity of inhalation and dermal exposures for each pesticide group for a given use during each decade. TEMPEST provides a basis for assessing exposures to specific pesticide groups in Scotland covering the period 1945-2005. The methods used to develop TEMPEST could be used in a retrospective assessment of occupational exposure to pesticides for Scottish epidemiological studies or adapted for use in other countries.

Occupational exposure to asbestos in New South Wales, Australia (1970–1989): development of an asbestos task exposure matrix

ObjectivesTo design and construct a standardised tool to provide exposure information associated with commonly used asbestos products and their related tasks in New South Wales (NSW), Australia.MethodsAsbestos dust exposure measurements...

Case–Control Study on Renal Cell Cancer and Occupational Exposure to Trichloroethylene. Part I: Exposure Assessment

A method for a semi-quantitative retrospective assessment of exposure to trichloroethylene (TCE) was implemented for a case-control study conducted in the Arve valley (France), an area with a widely developed screw-cutting industry, where teams of occupational physicians have collected a large quantity of well-documented measurements. A task-exposure matrix was developed to link the main working circumstances in a screw-cutting workshop to corresponding TCE-exposure levels: a 'basic level' was assigned to each task, standing for usual working procedures; exposure circumstances, such as duration or distance from the TCE source, were introduced as corrective factors. In parallel, a detailed occupational questionnaire was designed, setting subjects' descriptions of their successive jobs and working circumstances against levels assessed in the matrix. Possible exposure to TCE, plus some other occupational compounds (other solvents, oils, some metals, asbestos, welding fumes and ionizing radiations), were assessed for any job in all job histories. An average level of exposure to TCE, related to an 8 h usual working day, was attributed to each job period in turn, which was then categorized into six classes: 0; 1-35; 35-50; 50-75; 75-100; and >100 p.p.m. A total of 402 study subjects described their occupational life (average 3.7 jobs/subject, from 1924 to 2003). About 19% of the 1486 job periods described were assessed as being exposed to TCE; of these, 72.2% involved levels<35 p.p.m., 13.2% involved levels>50 p.p.m. and 5.4% above the French occupational exposure limit of 75 p.p.m. (TWA 8 h). A total of 41 job periods included exposure with peaks. Compared with levels encountered in other studies, the more severely exposed part of our study population seemed more exposed than most other populations previously studied, owing to vapor degreasing practices.

Beryllium Exposure Data: Rosenman et al. Respond

We thank Kolanz for his careful reading of our article (Rosenman et al. 2005). An erratum correcting the problem he noted appears on page A214. How do these corrected numbers change our results? More chronic beryllium disease (CBD) and sensitization occurred with exposure below the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 2 μg/m3 (OSHA 2005) than we previously reported, but no CBD or sensitization was found below the Department of Energy (DOE) guidelines of 0.2 μg/m3 (DOE 1999) or the even more protective level proposed by the American Conference of Governmental Industrial Hygienists (ACGIH 2005) of 0.02 μg/m3. There was an insufficient number of individuals—only three, and they were all normal—to assess the safety of the DOE guidelines or proposed ACGIH level. Our previously reported findings regarding chemical and physical form—that sensitized individuals compared with individuals with CBD had higher exposure to beryllium in a soluble form and to fumes of beryllium (Rosenman et al. 2005)—remain unchanged. However, the mean peak exposure for the sensitized group in our Table 8, the mean nonsoluble exposure for the sensitized group in Table 9, and the mean dust exposure for the sensitized group and mean fume exposure for the CBD group in Table 10 were no longer significantly different, whereas the peak fume exposure for the CBD group was now significantly different in Table 10. Having acknowledged and corrected the error pointed out by Kolanz, we take strong exception to his statement that “the study cannot sustain conclusions about the degree of risk associated with lower levels of exposure,” by which he means less than the OSHA PEL of 2 μg/m3 (OSHA 2005). One of Kolanz’s criticisms of our article (Rosenman et al. 2005) is that the daily weighted average (DWA) represented the daily exposure based on data averaged over 3 months. Breslin and Harris (1958) conducted a time study, which was updated as activities and location changed for each job title. During a 3-month period, three or more samples were collected and standardized to represent the general area where each person worked, and in some cases the breathing zone during work activities. The arithmetic average of the samples for each location/type was then calculated and weighted by time (Breslin and Harris 1958). Use of these summed weighted values, divided by the shift duration, is consistent with the American Industrial Hygiene Association (AIHA) exposure assessment guidance (Mulhausen and Damiano 1998) cited by Kolanz. We agree with Kolanz’s comment about the use of the flame spectroscopy method of chemical analysis and its general limit of detection of 0.1 μg/m3. In the job exposure matrix and task exposure matrix developed to support this project (Chen 2001), no exposure estimate was < 0.1 μg/m3, so this issue would have no effect on our results. Kolanz also takes exception with our estimates of mean exposures, stating that these values were derived by triple averaging. We derived the mean exposures as follows: for a given worker in a given job in a given year, we multiplied the number of days worked in that year for that worker by our best estimated DWA for that job in that year. We then summed those values over all jobs for that worker to derive that worker’s cumulative exposure. Next we divided that worker’s cumulative exposure by the total number of days worked in his/her job history to derive that worker’s mean exposure. Thus, there is only one averaging on each worker and a subsequent averaging for the population. We used multiple metrics (cumulative, average, peak job, and peak task for total exposure; exposure by chemical form; and exposure by physical form) to characterize not only the central tendencies of the exposures but also their extreme excursions. We stand by our statement that The inclusion of genetic data combined with exposure data may better define which individuals in this cohort are at a particularly high risk of development of CBD and/or sensitization and may account for the absence of typical exposure–response seen with other environmental or occupational toxins. It is also important to note that both peak exposure and the different chemical and physical forms may be important factors in the risk of development of CBD but are not part of the current OSHA standard (OSHA 2005). Finally, Kolanz states that “Rosenman et al. (2005) made no recommendations regarding how to protect beryllium workers.” Clearly, however, our call to lower the allowable standard is a recommendation we put forth to protect beryllium workers. Despite the limitations of deriving historical exposure estimates, our corrected data continue to point to the inadequacy of the current OSHA standard to protect workers from developing chronic beryllium disease.

Respiratory symptoms and lung-function changes with exposure to five substances in aluminium smelters.

To determine whether exposure to five different occupational substances contributes to respiratory symptoms in aluminium smelter workers. A cross-sectional survey of 1,615 male employees of two Australian aluminium smelters was conducted in 1995. Subjects underwent spirometry and were asked about respiratory symptoms and the relationship of those symptoms to work. Their job histories were combined with a task exposure matrix to produce individual quantitative measures of cumulative exposure to fluoride, sulphur dioxide, inspirable dust, the benzene-soluble fraction of coal tar pitch volatiles (BSF), and oil mist. After adjusting for smoking and age, we found that subjects with the highest cumulative exposure to fluoride (>0.16 mg/m(3) years) and inspirable dust (>2.9 mg/m(3) years) were two to four times more likely to report work-related wheeze and chest tightness than were unexposed subjects. Lower prevalence ratios for the same symptoms were seen with sulphur dioxide and BSF. Levels of lung function decreased slightly with exposure to oil mist, but not with cumulative exposure to other substances. This study suggests that the relevant causative agents for respiratory symptoms in aluminium smelters are fluoride and inspirable dust.

Reproducibility of Survey Results from a Study of Occupation-Related Respiratory Health in the Aluminum Industry

Confidence in dose-response relationships arising from occupational studies is dependent upon the reliability and validity of relevant exposure and morbidity estimates. Often self-reported occupational histories are a surrogate for direct exposure measures, and self-report of symptoms serves a similar purpose in place of more objective measures of morbidity. Unfortunately, there are few methods for validating either of these sources of information. This study attempts to evaluate the reproducibility of a survey instrument, and resulting cumulative exposure estimates, utilized in a study of work-related respiratory morbidity in the aluminum industry. The survey instrument comprised measures of pulmonary function, atopic status, smoking, occupational history, and respiratory symptoms. A Task Exposure Matrix was used to estimate exposure categories and cumulative exposure scores. Two groups of employees were administered the survey instrument on two separate occasions. Group A (n = 74) completed their two surveys more than ten weeks apart and Group B (n = 43) completed their surveys less than two weeks apart. Reproducibility was assessed using Cohen's Kappa for categorically measured outcome measures and intraclass correlation coefficients for continuously measured outcomes. Agreement across most variables, for both groups, was generally high. Repeatability of self-reported respiratory symptoms ranged from 70 to 98 percent (Group A) and 88 to 100 percent (Group B). Cumulative exposure scores were highly reproducible, despite some discrepancies in the self-reported occupational histories across interviews, with most of the calculated intraclass r scores exceeding 0.8. These results give strength to studies reporting dose-response relationships derived from similarly collected data. Reproducibility of the survey data was enhanced by use of standardized questionnaire material, consistent interview structure, and calibrated equipment for objective observation. In particular the authors recommend use of a company job dictionary to optimize reproducibility of self-reported occupational information.

Task profile and risk of occupational hepatitis A infection in sewerage workers.

The aim of the study was to assess to what extent parameters of task-related occupational exposure influence anti-hepatitis A virus (anti-HAV) seroprevalence in sewerage workers, using a new instrument for classification of exposure. A new instrument for the assessment of work-related infection hazards was developed based on expert interviews, evaluation of literature and theoretical considerations. It was included in a questionnaire for collecting detailed information on occupational exposure, safety awareness, safety behaviour and socio-demography. Anti-HAV status was assessed for all (n = 343) (non-vaccinated) study participants. Marked differences in task profile and task-related exposure within the group of sewerage workers were found, underlining the necessity of a detailed exposure analysis. In a multivariate model three risk factors that were related significantly to anti-HAV positivity were identified: age, country of origin and task-related exposure. Since task profiles and occupational exposure differ strongly within the job category of sewerage workers. evaluation of endangerment has to reflect individual task-related exposure. The task-exposure matrix developed and presented in this study is a practicable and valid instrument for exposure assessment and may be used for the exposure analysis of further biological agents in this working environment. Besides the known risk parameters age and origin, our study demonstrates a dose-response relationship between the degree of occupational exposure and the anti-HAV seroprevalence. Therefore, an effective worksite HAV-prevention programme should consider all technical, structural and educational measures that help to reduce individual exposure.

Respiratory symptoms and lung function in bauxite miners.

To determine whether cumulative bauxite exposure is associated with respiratory symptoms or changes in lung function in a group of bauxite miners. Current employees at three bauxite mines in Australia were invited to participate in a survey comprising: questionnaire on demographic details, respiratory symptoms, and work history; skin prick tests for four common aeroallergens; and spirometry. A task exposure matrix was constructed for bauxite exposure in all tasks in all jobs based on monitoring data. Data were examined for associations between cumulative bauxite exposure, and respiratory symptoms and lung function, by regression analyses. The participation rate was 86%. Self-reported work-related respiratory symptoms were reported by relatively few subjects (1.5%-11.8%). After adjustment for age and smoking no significant differences in the prevalence of respiratory symptoms were identified between subjects, in the quartiles of cumulative bauxite exposure distribution. The forced expiratory volume in I s (FEV1) of the exposed group was found to be significantly lower than that for the unexposed group. After adjustment for age, height, and smoking there were no statistically significant differences between quartiles in FEVI, forced vital capacity (FVC) and FEVl/FVC ratio. These data provide little evidence of a serious adverse effect on respiratory health associated with exposure to bauxite in an open-cut bauxite mine in present day conditions.

Respiratory Morbidity and Exposure to Bauxite, Alumina and Caustic Mist in Alumina Refineries

Respiratory Morbidity and Exposure to Bauxite, Alumina and Caustic Mist in Alumina Refineries: Lin Fritschi, et al. Department of Epidemiology and Preventive Medicine, Monash University—A cross‐sectional survey of 2404 employees in three alumina refineries was performed in 1996. The aims of this study were to investigate associations between respiratory symptoms and lung function and cumulative quantitative workplace exposure to alumina and bauxite dust, as well as recent workplace exposure to caustic mist. All participants answered questions about respiratory symptoms and the relationship of those symptoms to work, as well as having spirometry and providing a complete job history. The job histories were combined with a task exposure matrix for bauxite and alumina dust. The current job was also assigned a semi quantitative exposure to caustic mist. Prevalence ratios (PR) and 95% confidence intervals (Cl) for symptoms were calculated for each exposure. Subjects in the highest group of current caustic exposure reported increased prevalence of work related wheeze (PR=1.8 95% Cl 1.0‐3.1) and rhinitis (PR=1.6 95% Cl 1.1‐2.4) but did not have measurable changes in lung function. Alumina exposure was associated with minor increases in reporting of work related wheeze and rhinitis but no changes in lung function. Bauxite exposure at the levels experienced in these alumina refineries was not associated with either symptoms or lung function changes.

A task exposure database for use in the alumina and primary aluminium industry.

A task exposure database (TED) was developed to facilitate data collation for construction of a task exposure matrix (TEM) for Healthwise, a series of studies on cancer and respiratory morbidity in the alumina and primary aluminium industry. Following the construction of job classifications for the eight study sites, the site hygienists identified all historical air monitoring time-weighted average (TWA) data, from their respective sites. The earliest data were sampled in the late 1970s, and over 17,000 personal samples were recorded over the eight sites over a twenty-year period. TED, a Microsoft Access database, was developed for use by site occupational hygienists to collate these exposure data across the mines, refineries and smelters. All data conforming to strict criteria for use were recorded using TED and provided to the study group. Following the individual data point entry, a calculator program in TED systematically calculated the geometric means, arithmetic means, and maximum and minimum results at the task level. Other features of TED included fields for flagging "significant changes" and "stepwise changes" in exposure. TED established a standardised means of data collation that later formed the basis for the construction of a TEM for the study. A TEM is similar to a job exposure matrix (JEM) except that the basic unit of categorization is at the task level instead of at the job level. Both a TEM and JEM have been constructed independently for Healthwise. The possible reduction of exposure misclassification and improvement in validity of exposure characterization with the use of the TEM, is currently under investigation. The Healthwise TEM consists of annual TWA and peak data results for each site for various airborne contaminants, including fluorides, coal tar pitch volatiles, sulfur dioxide, inspirable dust, alumina dust, bauxite dust, and oil mist. Construction of the TEM for the Healthwise study was completed in late 1998 and consists of over 33,700 TWA years of task exposure data.

Occupational risk factors for renal cell carcinoma: agent-specific results from a case-control study in Germany

This case-control study was conducted to estimate the renal cell cancer (RCC) risk for exposure to occupation-related agents, besides other suspected risk factors. In a population-based multicentre study, 935 incident RCC cases and 4298 controls matched for region, sex, and age were interviewed between 1991 and 1995 for their occupational history and lifestyle habits. Agent-specific exposure was expert-rated with two job-exposure matrices and a job task-exposure matrix. Conditional logistic regression was used to calculate smoking adjusted odds ratios (OR). Very long exposures in the chemical, rubber, and printing industries were associated with risk for RCC. Males considered as 'substantially exposed to organic solvents' showed a significant excess risk (OR = 1.6, 95% CI : 1.1-2.3). In females substantial exposure to solvents was also a significant risk factor (OR = 2.1, 95% CI : 1.0-4.4). Excess risks were shown for high exposure to cadmium (OR = 1.4, 95% CI : 1.1-1.8, in men, OR = 2.5, 95% CI : 1.2-5.3 in women), for substantial exposure to lead (OR = 1.5, 95% CI : 1.0-2.3, in men, OR = 2.6, 95% CI : 1.2-5.5, in women) and to solder fumes (OR = 1.5, 95% CI : 1.0-2.4, in men). In females, an excess risk for the task 'soldering, welding, milling' was found (OR = 3.0, 95% CI : 1.1-7.8). Exposure to paints, mineral oils, cutting fluids, benzene, polycyclic aromatic hydrocarbons, and asbestos showed an association with RCC development. Our results indicate that substantial exposure to metals and solvents may be nephrocarcinogenic. There is evidence for a gender-specific susceptibility of the kidneys.

Beyond the job exposure matrix (JEM): the task exposure matrix (TEM)

The job exposure matrix (JEM) has been employed to assign cumulative exposure to workers in many epidemiological studies. In these studies, where quantitative data are available, all workers with the same job title and duration are usually assigned similar cumulative exposures, expressed in mgm−3×years. However, if the job is composed of multiple tasks, each with its own specific exposure profile, then assigning all workers within a job the same mean exposure can lead to misclassification of exposure. This variability of exposure within job titles is one of the major weaknesses of JEMs. A method is presented for reducing the variability in the JEM methodology, which has been called the task exposure matrix (TEM). By summing the cumulative exposures of a worker over all the tasks worked within a job title, it is possible to address the variability of exposure within the job title, and reduce possible exposure misclassification. The construction of a TEM is outlined and its application in the context of a study in the primary aluminium industry is described. The TEM was found to assign significantly different cumulative exposures to the majority of workers in the study, compared with the JEM and the degree of difference in cumulative exposure between the JEM and the TEM varied greatly between contaminants.

Beyond the Job Exposure Matrix (JEM): the Task Exposure Matrix (TEM)

The job exposure matrix (JEM) has been employed to assign cumulative exposure to workers in many epidemiological studies. In these studies, where quantitative data are available, all workers with the same job title and duration are usually assigned similar cumulative exposures, expressed in mgm(-3)xyears. However, if the job is composed of multiple tasks, each with its own specific exposure profile, then assigning all workers within a job the same mean exposure can lead to misclassification of exposure. This variability of exposure within job titles is one of the major weaknesses of JEMs. A method is presented for reducing the variability in the JEM methodology, which has been called the task exposure matrix (TEM). By summing the cumulative exposures of a worker over all the tasks worked within a job title, it is possible to address the variability of exposure within the job title, and reduce possible exposure misclassification. The construction of a TEM is outlined and its application in the context of a study in the primary aluminium industry is described. The TEM was found to assign significantly different cumulative exposures to the majority of workers in the study, compared with the JEM and the degree of difference in cumulative exposure between the JEM and the TEM varied greatly between contaminants.

Occupational risk factors for urothelial carcinoma: agent-specific results from a case-control study in Germany

This multicentre population-based case-control study was conducted to estimate the urothelial cancer risk for occupational exposure to aromatic amines, polycyclic aromatic hydrocarbons (PAH), and chlorinated hydrocarbons besides other suspected risk factors. In a population-based multicentre study, 1035 incident urothelial cancer cases and 4298 controls matched for region, sex, and age were interviewed between 1991 and 1995 for their occupational history and lifestyle habits. Exposure to the agents under study was self-assessed as well as expert-rated with two job-exposure matrices and a job task-exposure matrix. Conditional logistic regression was used to calculate smoking adjusted odds ratios (OR) and to control for study centre and age. Urothelial cancer risk following exposure to aromatic amines was only slightly elevated. Among males, substantial exposures to PAH as well as to chlorinated solvents and their corresponding occupational settings were associated with significantly elevated risks after adjustment for smoking (PAH exposure, assessed with a job-exposure matrix: OR = 1.6, 95% CI: 1.1-2.3, exposure to chlorinated solvents, assessed with a job task-exposure matrix: OR = 1.8, 95% CI: 1.2-2.6). Metal degreasing showed an elevated urothelial cancer risk among males (OR = 2.3, 95% CI: 1.4-3.8). In females also, exposure to chlorinated solvents indicated a urothelial cancer risk. Because of small numbers the risk evaluation for females should be treated with caution. Occupational exposure to aromatic amines could not be shown to be as strong a risk factor for urothelial carcinomas as in the past. A possible explanation for this finding is the reduction in exposure over the last 50 years. Our results strengthen the evidence that PAH may have a carcinogenic potential for the urothelium. Furthermore, our results indicate a urothelial cancer risk for the use of chlorinated solvents.