Impact of an occupational health promotion program on subsequent illness and mortality experience.

BACKGROUND: Integrating general health initiatives into established occupational health programs may be an effective way of contributing more broadly to employee health. Objective assessment of the success of such initiatives is needed, but is often difficult to carry out because of their voluntary nature. METHODS: A cohort of 24,586 wage employees, 35+ years of age and with 15+ years of prior employment, was established to assess morbidity and mortality outcomes relative to participation in an ongoing health initiative instituted in 1983. Outcomes were evaluated for employees who attended the seminar program (attendees), those who had clearance examinations, but did not take part in the program (withdrawals), and non-participants. RESULTS: At entry to follow-up, the prevalence of chronic illnesses including diabetes, obesity, and diseases of the circulatory system was lowest among non-participants and highest among withdrawals. During the follow-up period, the incidence of new disease conditions was similar between attendees and non-participants; however, overall mortality was significantly reduced among attendees after adjustment for explanatory factors including age, job grade, smoking history, alcohol intake, and body-mass-index (relative risk = 0.83; 95% confidence interval: 0.69-0.99) and was still marginally decreased when withdrawals were combined with attendees. CONCLUSIONS: Although self-selection cannot be ruled out as a contributing factor to the reduction in mortality risk among attendees, our findings indicate that offering health promotion activities in the context of an existing occupational health program may benefit overall employee health.

Medical program for shift workers--impacts on chronic disease and mortality outcomes.

OBJECTIVE: In 1983, global chemical company BASF SE implemented a supplemental health protection program to help its employees cope with the stressors associated with shift work. The program included comprehensive medical examinations and health promotion activities targeted at shift workers. METHODS: To assess the possible long-term health impacts of the program, cohorts of 14,128 male rotating shift and 17,218 male day wage employees were established via electronic job history searches. Health examination and mortality records were linked to job histories and studied over an 11-year period. RESULTS: Between 1996 and 2006, there were 414 and 463 deaths among rotating shift and day work employees, respectively. Mortality risks were marginally lower among shift working employees when taking age and job level into consideration, and remained so when cigarette smoking, alcohol intake, and existing chronic disease conditions were included as explanatory factors. The incidence of obesity, diabetes, and diseases of the circulatory and digestive system, as diagnosed or reported during health examinations, was higher among shift work employees, possibly as a consequence of enhanced medical surveillance or a direct effect of shift work. CONCLUSION: Incorporation of extensive occupational medical examinations, health seminars, and other intervention programs may help mitigate the long-term health consequences of shift work.

Pregnancy protection program in a large chemical company: design and initial survey results.

OBJECTIVES: To describe the BASF pregnancy protection program and provide initial results regarding selected pregnancy outcomes. METHODS: Pregnancies (n=1148) occurring between 1997 and 2002 were identified and outcomes were documented by questionnaires administered after the pregnancy announcement, end of pregnancy, and one year later. Potential maternal exposures were assessed via job histories, workplace inspections, and questionnaire. RESULTS: Participation was 90% overall and was consistently high across employee subgroups. Pregnancy losses (11.5%) did not differ significantly by type of work. Among pregnancy symptoms vaginal bleeding was weakly associated with two exposure measures. Preterm births (8.7%) were in agreement with general population norms and did not vary by maternal exposure category. CONCLUSIONS: High participation rates and a structured approach to employee education and documentation of reproductive outcomes may be of value in addressing reproductive health issues in the workplace.

Pregnancy protection program in a large chemical company: infant outcomes.

OBJECTIVES: The purpose of this study was to investigate reproductive outcomes in infants relative to maternal exposures in the chemical industry. METHODS: Via questionnaires administered after the pregnancy announcement, end of pregnancy, and 1 year later, infant outcomes were documented for 1147 live births. Maternal exposure factors were evaluated relative to birth height and weight, sex ratio, Apgar score at 5 minutes, and major malformations. RESULTS: Birth height and weight, sex ratio, and Apgar score did not differ by maternal work area or chemical hazard categories. Major malformations (3.1%) and organ-specific anomalies were consistent with the experience of a regional birth defects registry. Rates of malformation were marginally higher in infants born to women assigned to chemical versus office jobs. CONCLUSIONS: Infant outcomes to date have been consistent with comparable findings from population-based studies. Longer-term observation will be needed to assess trends for low-frequency outcomes and more specific maternal exposures.

Investigation of cancer occurrences associated with an herbicide manufacturing facility.

This study evaluated cancer incidence and mortality among 251 employees of a facility that synthesized a benzothiadiazin herbicide between 1979-1987. It was initiated in response to a perceived cancer cluster. Cancers were identified mainly by review of occupational medical records and personal interviews. Standardized incidence ratios (SIRs) were computed using comparison data provided by the Louisiana Tumor Registry. Overall mortality was less than expected and did not vary by job type or duration of assignment in the facility. Total cancer incidence was marginally elevated [SIR = 1.4; 95% Confidence Interval (CI): 0.9-1.9] and was highest among men assigned to the unit during 1979 [SIR = 2.1; 95% CI: 1.3-3.3]. Thirteen of 20 cancers among these men were either prostate (9) or digestive system (4) cancers. Increased medical examinations and cancer awareness may have contributed to the detection of cancers at earlier ages than would be seen in a general population. No specific workplace agents were identified to account for the findings although a workplace role cannot be ruled out.

Exposure assessment as a component of observational health studies and environmental risk assessment.

Assessing pesticide and nonpesticide exposures in agricultural settings is a daunting task. This is especially the case when such assessments are undertaken as a component of health studies to evaluate cancer risk. In this review, key exposure assessment issues are outlined and discussed in the context of pesticide-specific health risk assessments and three recent studies of large, geographically defined farmer and farm family populations. The specific topics addressed include the assessment of cumulative exposures to both older and more recently registered pesticides, the role of biomarker studies in exposure assessment, and uses of data on nonroutine high-exposure events.

Illness experience before and after an initiative to identify, treat, and prevent Helicobacter pylori-related diseases in the workplace.

Objective outcome measures are needed to confirm the merits of large-scale health initiatives in the workplace. We used aggregate medical claims data to evaluate the illness experience of 5160 employees during the 2 years after versus the 2 years before an intervention intended to identify, treat, and prevent Helicobacter pylori-related illnesses. Across all participants, a 2.1-fold reduction (95% confidence interval 1.4-3.1) in ulcer-related illness episodes and a marginal 1.1-fold reduction (95% confidence interval 0.9-1.4) in episodes due to other stomach and duodenal diseases were achieved. Improvement in claims experience was most notable among 250 employees with ulcer findings on the screening examination. This H. pylori health initiative appears to have contributed to a cost-effective reduction in subsequent illness episodes due to ulcer and possibly due to other stomach and duodenal disease.

[Dyspepsia and Helicobacter pylori infection in employees of a large industry. Results of a prospective BASF Helicobacter pylori prevention campaign]. / Dyspepsie und Helicobacter-pylori-Infektion bei Beschäftigten eines grossen Industrieunternehmens. Ergebnisse der prospektiven BASF-Helicobacter-pylori-Vorsorgeaktion.

BACKGROUND: The role of Helicobacter pylori (H. pylori) infection in dyspepsia is controversial. In the course of a health initiative within a large industrial corporation, we investigated the prevalence of both dyspepsia and positive H. pylori serology and the outcome of eradication therapy in symptomatic H. pylori positive employees. TEST PERSONS AND METHODS: H. pylori serology (IgG ELISA) was determined in 6,143 employees of BASF AG Ludwigshafen/Germany who were also asked to complete a standardized health history administered by a physician. Peptic ulcer disease (PUD) and dyspepsia subgroups were defined based on past medical history and symptom profiles using the criteria of Heading. Upper GI endoscopy, abdominal ultrasound and eradication therapy (Italian Triple Therapy) was recommended for symptomatic H. pylori positive individuals. The prognostic value of antibodies against CagA and VacA was evaluated in 37 and 39 employees with PUD and non-ulcer dyspepsia (NUD) confirmed by endoscopy, respectively. RESULTS: Of 6,143 employees, 1,255 (20.4%) were classified as dyspeptic, 492 (39.2%) of whom were H. pylori positive. The seroprevalence of H. pylori in asymptomatic employees was 35.8%. There were no significant differences in H. pylori seroprevalence among dyspepsia subgroups (reflux only, dysmotility only, reflux/dysmotility, ulcer-like and non-specific). However, individuals reporting severe dyspeptic symptoms were significantly more likely to be H. pylori positive (OR 2.09, CI 1.43-3.05). The seroprevalence of CagA and VacA was not significantly different among employees with NUD compared to referents or among employees with NUD compared to those with PUD. 330 (72%) of 458 employees with dyspepsia received eradication therapy, 128 persons refused therapy. Based on a 12-month follow-up of 402 individuals (300 of whom had received therapy), eradication success was 81.5% as judged by serology. Of the successfully treated employees, 33.2% reported a total absence and 42.8% reported a decrease in symptoms. Among the employees who refused therapy, the corresponding percentages were 37.3% and 16.7%, respectively. An increase in reflux complaints was not observed among treated employees. CONCLUSION: In a large active employee population, at most a very weak association was observed between the prevalence of H. pylori seropositivity and dyspepsia. Frequent and severe dyspeptic symptoms were associated with an increased rate of H. pylori seropositivity. The analysis of the virulence factors is not particularly helpful in discriminating PUD or NUD. Eradication of H. pylori infection leads to a decrease in dyspeptic symptoms after 12 months, but not more often to their complete absence compared to untreated individuals.

Health and safety protection for chemical industry employees in a rotating shift system: program design and acute injury and illness experience at work.

OBJECTIVES: To describe a comprehensive health protection program for rotating shift employees and evaluate the program effectiveness in injury and illness prevention. METHODS: For 14,128 shift and 17,218 day wage employees, occupational medical records were linked to job assignment records and studied over an 11-year period. RESULTS: Between 1995 and 2005, initiatives directed to shift employees contributed to their 59% and 100% greater participation in medical examinations and health seminar days, respectively, compared to day wage employees. Injury rates declined over time and with increasing employee age and were not elevated among rotating shift compared to day wage employees. Clinic visit rates for acute illnesses were generally higher for day than shift work employees. CONCLUSION: Coupling of active medical monitoring with additional health and safety initiatives appears to mitigate the expected adverse physiological and psychosocial stresses of shift work.

Screening for pre-diabetes and diabetes in the workplace.

BACKGROUND: Diabetes is an increasingly prevalent and burdensome disease in working populations. In settings with established occupational medical programmes, there may be opportunities to intervene in a positive way to reduce the burden of this disease. AIM: To integrate diabetes screening and prevention into an existing occupational medical programme. METHODS: Screening to detect potential cases of pre-diabetes and diabetes was conducted in a large working population using differing criteria to define risk groups over a 2-year period. Classification of new cases was based on fasting plasma glucose, random plasma glucose or oral glucose tolerance test (OGTT). RESULTS: Among 13,086 employees screened via fasting or random glucose, there were 96 diabetes and 650 pre-diabetes cases detected. Among high-risk employees, 20 new cases of pre-diabetes and 8 cases of diabetes were detected in 84 employees assessed by OGTT. The percentage of employees with new findings increased with increasing age (2.3%, under age 40 compared to 11.4% for age 50 years and above) and body mass index (2.6, 6.1 and 11.4% among normal weight, overweight and obese employees, respectively). CONCLUSIONS: Given the likely magnitude of unrecognized diabetes and pre-diabetes cases, further interventions are being implemented targeting all employees and not just those who require routine occupational medical examinations.

Issues in diisocyanate antibody testing.

Diisocyanates are used to produce a wide variety of polyurethane products; they are also recognized as an important cause of occupational asthma. Their chemical reactivity presents challenges to toxicologists and clinicians alike seeking to understand the mechanisms underlying diisocyanate asthma. In this article, we review the literature on immunoassay detection of IgE and IgG binding to diisocyanate-protein conjugates and assess the utility of such testing as a diagnostic tool and exposure indicator. Data from 29 studies of occupational exposure to diisocyanates revealed considerable variability in assay methodology and heterogeneity in the prevalence of positive antibody responses across laboratories. In studies that included both confirmed diisocyanate asthma subjects and exposed nonasthmatics, positive IgE responses identified cases with low sensitivity (18-27%), but high specificity (96-98%). Detection of IgG binding to diisocyanate conjugates is an indirect, qualitative indicator of disease status and past diisocyanate exposure. The utility of these assays is limited, however, due to a lack of (1) method standardization, (2) population norms to guide interpretation of results, and (3) demonstration that the assays improve either on disease prediction or on exposure confirmation beyond that of other indicators. Sources of assay heterogeneity are discussed and suggestions are offered for improving test performance and interpretability.

Evaluation of antibody binding to diisocyanate protein conjugates in a general population.

BACKGROUND: Specific IgG binding to diisocyanate-human serum albumin (HSA) has been proposed as an indicator of diisocyanate exposure. One residential study reported IgG binding to diisocyanate conjugates in 8% of residents living near a factory using toluene diisocyanate (TDI). Because comparable assays were not performed using individuals distant from such facilities, the significance of this finding is uncertain. OBJECTIVE: To determine the prevalence of diisocyanate specific antibodies in sera from individuals "not known to be exposed" to diisocyanates. METHODS: Serum samples from 139 anonymous donors without known diisocyanate exposure were assayed by means of enzyme-linked immunosorbent assay for IgG or IgE specific for TDI-HSA, diphenylmethane diisocyanate (MOI)-HSA, and hexamethylene diisocyanate (HDI)-HSA. Positive responses (optical density > or = 0.1 and > or = 3 SDs above the mean of 8 laboratory controls) were run 3 times. Competitive inhibition was performed for sera exhibiting binding of optical density of at least 0.2. RESULTS: We detected IgG reactive with HDI-HSA, diphenylmethane diisocyanate-HSA, and TDI-HSA in 18 (13%), 0, and 7 donors (5%), respectively. Inhibition (>50%) was demonstrated in 6 of 9 participants with elevated HDI-HSA levels and in 2 of 7 with elevated TDI-HSA levels. We detected IgE reactive with the same antigens in 3 donors (2%); however, none were confirmed to be positive using the biotin-streptavidin IgE assay. CONCLUSIONS: Specific and nonspecific IgG binding to HDI-HSA and TDI-HSA were detected in individuals without known exposure to isocyanates. These antibody measurements may not be reliable indicators of diisocyanate exposure in nonoccupational populations and should not be interpreted as surrogates of diisocyanate exposure in the absence of defined referent populations.

Occupational asthma, lung function decrement, and toluene diisocyanate (TDI) exposure: a critical review of exposure-response relationships.

An extensive amount of clinical/epidemiological literature exists regarding the effects of toluene diisocyanate (TDI) exposure on respiratory health. This review presents an evaluation and synthesis of that literature with an emphasis on assessing exposure-response relationships in the workplace. The key respiratory disorders examined are bronchial asthma and an accelerated decline in lung function. In the early years of the industry, annual incidence rates of TDI-induced occupational asthma (OA) were as high as 5-6 percent. In settings where mean TDI concentrations have been maintained below 5 ppb based on 8-hr personal samples, OA incidence rates have declined to < 1 percent annually. Recent data also suggest that overexposure incidents may play an important role in inducing OA, particularly in work environments engineered to minimize routine ambient air concentrations. Fourteen studies were reviewed that examined lung function decrement. Early studies from the 1960s and 1970s provided evidence of transient or fixed lung function loss (measured as a decline in forced expiratory volume in one second [FEV1]) during periods of ongoing exposure among employees experiencing high rates of work-related symptoms of OA. Such findings would not be unexpected in that modest FEV1 declines have been demonstrated in general population studies of persons with bronchial hyperresponsiveness or persistent non-occupational asthma. More recent workplace studies have provided no consistent evidence of accelerated FEV1 loss among employees exposed up to 5 ppb TDI (8-hr TWA) even with documented routine short-term TDI concentrations exceeding 20 ppb TDI.

Respiratory effects of toluene diisocyanate in the workplace: a discussion of exposure-response relationships.

Toluene diisocyanate (TDI) is an important industrial intermediate used in manufacturing flexible polyurethane (PUR) foams, surface coatings, cast elastomers, sealants, and adhesives. In this review long-term trends in workplace exposures to TDI are assessed in both the producing and using industries, and respiratory health effects of TDI are evaluated in relation to workplace TDI concentrations. The key respiratory health effects associated with repeated or long-term TDI exposure are bronchial asthma and an accelerated rate of decline in lung function. In the early years of the industry, annual incidence rates of occupational asthma (OA) due to TDI ranged from 1% to as high as 5 to 6%, depending on the extent of engineering and work practice controls in the various workplaces. Since the mid-1970s, annual OA incidence rates have been <1%, where 8 h TDI concentrations have been maintained below 5 ppb as determined by personal monitoring, even where short-termTDI concentrations above 20 ppb and less frequently above 40 ppb were routinely detected. In these latter settings, there is evidence that the majority of OA cases may be attributable to TDI concentrations well above 20 ppb associated with overexposure incidents. Further study is needed regarding the role of such incidents in inducing respiratory sensitization. Cross-sectional and longitudinal studies of lung function have indicated that continued exposure after development of work-related respiratory symptoms can lead to transient or accelerated fixed declines in forced expiratory volume in 1 sec (FEV1). These findings are congruent with the FEV1 declines demonstrated in general population studies of persons with persistent bronchial hyperresponsiveness or nonoccupational asthma. More recent longitudinal studies in settings with ongoing medical surveillance have provided no consistent evidence of accelerated FEV1 loss among employees exposed up to 5 ppb TDI on an 8 h time-weighted average basis.