Maternal occupational noise exposure during pregnancy and children's early language acquisition.

INTRODUCTION: Noise exposure during pregnancy may affect a child's auditory system, which may disturb fetal learning and language development. We examined the impact of occupational noise exposure during pregnancy on children's language acquisition at the age of one. METHODS: A cohort study was conducted among women working in the food industry, as kindergarten teachers, musicians, dental nurses, or pharmacists who had a child aged <1 year. The analyses covered 408 mother-child pairs. Language acquisition was measured using the Infant-Toddler Checklist. An occupational hygienist assessed noise exposure individually as no (N = 180), low (70-78 dB; N = 108) or moderate/high exposure (>79 dB; N = 120). RESULTS: Among the boys, the adjusted mean differences in language acquisition scores were -0.4 (95% CI -2.5, 1.8) for low, and -0.7 (95% CI -2.9, 1.4) for moderate/high exposure compared to no exposure. Among the girls the respective scores were +0.1 (95% CI -2.2, 2.5) and -0.1 (95% CI -2.3, 2.2). Among the children of kindergarten teachers, who were mainly exposed to human noise, low or moderate exposure was associated with lower language acquisition scores. The adjusted mean differences were -3.8 (95% CI -7.2, -0.4) for low and -4.9 (95% CI -8.6, -1.2) for moderate exposure. CONCLUSIONS: In general, we did not detect an association between maternal noise exposure and children's language acquisition among one-year-old children. However, the children of kindergarten teachers exposed to human noise had lower language acquisition scores than the children of the non-exposed participants. These suggestive findings merit further investigation by level and type of exposure.

Work-Related Outcomes in Self-Employed Cancer Survivors: A European Multi-country Study.

Purpose To describe: (i) patterns of self-employment and social welfare provisions for self-employed and salaried workers in several European countries; (ii) work-related outcomes after cancer in self-employed people and to compare these with the work-related outcomes of salaried survivors within each sample; and (iii) work-related outcomes for self-employed cancer survivors across countries. Methods Data from 11 samples from seven European countries were included. All samples had cross-sectional survey data on work outcomes in self-employed and salaried cancer survivors who were working at time of diagnosis (n = 22-261 self-employed/101-1871 salaried). The samples included different cancers and assessed different outcomes at different times post-diagnosis. Results Fewer self-employed cancer survivors took time off work due to cancer compared to salaried survivors. More self-employed than salaried survivors worked post-diagnosis in almost all countries. Among those working at the time of survey, self-employed survivors had made a larger reduction in working hours compared to pre-diagnosis, but they still worked more hours per week post-diagnosis than salaried survivors. The self-employed had received less financial compensation when absent from work post-cancer, and more self-employed, than salaried, survivors reported a negative financial change due to the cancer. There were differences between self-employed and salaried survivors in physical job demands, work ability and quality-of-life but the direction and magnitude of the differences differed across countries. Conclusion Despite sample differences, self-employed survivors more often continued working during treatment and had, in general, worse financial outcomes than salaried cancer survivors. Other work-related outcomes differed in different directions across countries.

Paternal occupational lead exposure and offspring risks for schizophrenia.

This register-based cohort study investigated whether paternal occupational exposure to inorganic lead was related to offspring risk for schizophrenia spectrum disorder (SSD). Exposed men (n=11,863) were identified from blood lead measurements taken at the Finnish Institute of Occupational Health in 1973-1983. Data on mothers and their offspring born from 1972-1984 were obtained from the national Population Information System. Two population comparison offspring for each exposed offspring were matched on date of birth, sex and area (n=23,720). SSD cases were identified from The Finnish Hospital Discharge Register. Hazard ratios of SSD between exposed groups were analyzed using conditional proportional hazards regression, adjusted for parental history of psychoses, parental ages, language of offspring, father's employment, and father's self-employment. After 26-38years of follow up, there were no significant differences in the incidence of schizophrenia, either between the offspring of exposed (188/11,863; 1.6%) and unexposed fathers (347/23,720; 1.5%) or based on blood lead levels (adjusted hazard ratios (aHR): 0.97, CI 0.52-1.83, 1.25, CI 0.85-1.82, 0.90, CI 0.54-1.49, and 1.38, CI 0.65-2.92 for lead categories <0.5, 0.5-0.9, 1.0-1.4, and ≥1.5µmol/L, respectively, as compared to population comparison). Parental psychosis, paternal age and offspring language were associated with offspring risk. The findings suggest that paternal exposure to lead is not a risk factor for schizophrenia in offspring. However, the majority of exposed fathers had low-level exposure, and we cannot exclude the possibility of an effect for higher exposures to lead.

Psychosocial factors at work and obesity among young finnish adults: a cohort study.

OBJECTIVE: To examine the associations between occupational psychosocial factors and obesity among 31-year-olds, adjusting for adolescent body mass index, physical strenuousness of work, and adverse health behaviors (ie, stress-related eating/drinking, leisure-time physical inactivity, smoking, and high alcohol consumption). METHODS: The study population comprised 2083 men and 1770 women from the Northern Finland Birth Cohort 1966. Obesity was defined as a body mass index of 30.0 kg/m or more. Psychosocial exposures were defined in terms of demands, control, and social support at work. RESULTS: Among men, high job demands and low worksite social support were independently associated with obesity. Among women, stress-related eating/drinking and physical inactivity seemed to promote obesity. Body mass index at age 14 was an important predictor of obesity for both sexes. CONCLUSIONS: In workplace obesity prevention programs, it might be beneficial to improve the psychosocial work environment and promote healthy behaviors simultaneously.

Employment participation and work experience of male cancer survivors: a NOCWO study.

OBJECTIVE: To investigate whether employment status and work experiences, assessed in terms of job resources (organizational culture and superiors' and co-workers' support), commitment to organization, work motives, and experiences of discrimination, differ between survivors of prostate or testicular cancer or lymphoma and cancer-free reference subjects. METHODS: Questionnaires were sent to 1349 male cancer survivors and 2666 referents in Denmark, Finland, Iceland, and Norway. Valid responses were 59% and 45%, respectively. Odds ratios (OR) and 95% confidence intervals (CI) were estimated with logistic regression models. RESULTS: Compared to the referents, survivors of lymphoma and prostate cancer were less likely to be employed (OR=0.53; CI: 0.30-0.95 and OR=0.50; CI: 0.35-0.73, respectively), but decreased employment was not evident among testicular cancer survivors. Testicular cancer survivors experienced less discrimination at work than did the referents, for example, testicular cancer survivors were less likely to report that their colleagues doubted their ability to carry out their work tasks (OR=0.38; CI: 0.17-0.83). Lymphoma survivors were less likely than the referents to praise their workplace as an enjoyable place to work (OR=0.48; CI: 0.26-0.88). The prostate cancer survivors were more likely than the referents to find the organizational climate competitive, distrustful, and suspicious. CONCLUSIONS: Employment participation and work experiences of male cancer survivors varied substantially according to type of cancer. Occupational therapists and other health care personnel should keep this in mind when assisting cancer survivors in identifying their strengths and limitations at work.

Night-shift work and breast cancer--a systematic review and meta-analysis.

OBJECTIVE: The aim of this review was to synthesize the evidence on the potential relationship between nightshift work and breast cancer. METHODS: We searched multiple databases for studies comparing women in shift work to those with no-shift work reporting incidence of breast cancer. We calculated incremental risk ratios (RR) per five years of night-shift work and per 300 night shift increases in exposure and combined these in a random effects dose-response meta-analysis. We assessed study quality in ten domains of bias. RESULTS: We identified 16 studies: 12 case-control and 4 cohort studies. There was a 9% risk increase per five years of night-shift work exposure in case-control studies [RR 1.09, 95% confidence interval (95% CI) 1.02-1.20; I (2) = 37%, 9 studies], but not in cohort studies (RR 1.01, 95% CI 0.97-1.05; I (2) = 53%, 3 studies). Heterogeneity was significant overall (I (2) = 55%, 12 studies). Results for 300 night shifts were similar (RR 1.04, 95% CI 1.00-1.10; I (2) = 58%, 8 studies). Sensitivity analysis using exposure transformations such as cubic splines, a fixed-effect model, or including only better quality studies did not change the results. None of the 16 studies had a low risk of bias, and 6 studies had a moderate risk. CONCLUSIONS: Based on the low quality of exposure data and the difference in effect by study design, our findings indicate insufficient evidence for a link between night-shift work and breast cancer. Objective prospective exposure measurement is needed in future studies.

Exposure assessment for a nested case-control study of lung cancer among European asphalt workers.

OBJECTIVE: Development of a method for retrospective assessment of exposure to bitumen fume, bitumen condensate, organic vapour, polycyclic aromatic hydrocarbons, and co-exposures to known or suspected lung carcinogens for a nested case-control study of lung cancer mortality among European asphalt workers. METHODS: Company questionnaires and structured questionnaires used in interviews and industry-specific job-exposure matrices (JEMs) were elaborated and applied. Three sources of information were eventually used for exposure assessment and assignment: (i) data obtained in cohort phase, (ii) data from living subjects, next-of-kin, and fellow-workers questionnaires, and (iii) JEMs for bitumen exposure by inhalation and via skin and co-exposures to known or suspected lung carcinogens within and outside cohort companies. Inhalation and dermal exposure estimates for bitumen were adjusted for time trends, time spent in a job, and other determinants of exposure (e.g. oil gravel paving). Clothing patterns, personal protective devices, and personal hygiene were taken into consideration while estimating dermal exposure. RESULTS: Occupational exposures could be assessed for 433 cases and 1253 controls for relevant time periods. Only 43% of work histories were spent inside original asphalt and construction companies. A total of 95.8% of job periods in cohort companies could be coded at a more detailed level. Imputation of work time and 'hygienic behaviour' multipliers was needed for <10% of work history years. Overall, downward trends in exposure were present and differences existed between countries and companies. As expected, correlations were strongest (r > 0.7) among bitumen-related agents, while correlations between coal tar, bitumen-related agents, and established lung carcinogens were weaker (r < 0.4). CONCLUSIONS: A systematic and detailed approach was developed to estimate inhalation and dermal exposure for a nested case-control study among asphalt workers.

A case-control study of lung cancer nested in a cohort of European asphalt workers.

BACKGROUND: We conducted a nested case-control study in a cohort of European asphalt workers in which an increase in lung cancer risk has been reported among workers exposed to airborne bitumen fume, although potential bias and confounding were not fully addressed. OBJECTIVE: We investigated the contribution of exposure to bitumen, other occupational agents, and tobacco smoking to the risk of lung cancer among asphalt workers. METHODS: Cases were cohort members in Denmark, Finland, France, Germany, the Netherlands, Norway, and Israel who had died of lung cancer between 1980 and the end of follow-up (2002-2005). Controls were individually matched in a 3:1 ratio to cases on year of birth and country. We derived exposure estimates for bitumen fume and condensate, organic vapor, and polycyclic aromatic hydrocarbons, as well as for asbestos, crystalline silica, diesel motor exhaust, and coal tar. Odds ratios (ORs) were calculated for ever-exposure, duration, average exposure, and cumulative exposure after adjusting for tobacco smoking and exposure to coal tar. RESULTS: A total of 433 cases and 1,253 controls were included in the analysis. The OR was 1.12 [95% confidence interval (CI), 0.84-1.49] for inhalation exposure to bitumen fume and 1.17 (95% CI, 0.88-1.56) for dermal exposure to bitumen condensate. No significant trend was observed between lung cancer risk and duration, average exposure, or cumulative exposure to bitumen fume or condensate. CONCLUSIONS: We found no consistent evidence of an association between indicators of either inhalation or dermal exposure to bitumen and lung cancer risk. A sizable proportion of the excess mortality from lung cancer relative to the general population observed in the earlier cohort phase is likely attributable to high tobacco consumption and possibly to coal tar exposure, whereas other occupational agents do not appear to play an important role.

Risk of liver cancer and exposure to organic solvents and gasoline vapors among Finnish workers.

We investigated the association between exposure to various groups of solvents and gasoline vapors and liver cancer. A cohort of economically active Finns born between 1906 and 1945 was followed up during the period 1971-1995. The incident cases of primary liver cancer (n = 2474) were identified in a record linkage with the Finnish Cancer Registry. Occupations from the 1970 census were converted to exposures using a job-exposure matrix. Cumulative exposure was calculated as the product of estimated prevalence, level and duration of exposure, and we used Poisson regression to calculate the relative risks (RR). Among the occupations entailing exposure to organic solvents, an elevated liver cancer incidence was observed in male printers, and varnishers and lacquerers. Among men, the risk was increased in the highest exposure category of aromatic hydrocarbons [RR 1.77, 95% confidence interval (CI) 1.30-2.40], aliphatic/alicyclic hydrocarbons (RR 1.47, 95% CI 0.99-2.18), chlorinated hydrocarbons (RR 2.65, 95% CI 1.38-5.11) and "other solvents" (RR 2.14, 95% CI 1.23-3.71). Among women, the risk was increased for the group "other solvents" that includes mainly alcohols, ketones, esters and glycol ethers (RR 2.73, 95% CI 1.21-6.16). Our finding of an increased risk among workers exposed to chlorinated hydrocarbons is in line with several earlier studies on trichloroethylene. The results also suggest a link between exposure to other types of solvents and the risk of liver cancer. The possibility that alcohol consumption contributes to the observed risks cannot be totally excluded.

Received and needed social support at the workplace in Norwegian and Finnish stage 1 breast cancer survivors: a study from the Nordic Study Group of Cancer and Work (NOCWO).

BACKGROUND: Cross-cultural studies of comparable patients can identify differences of health care services and point to issues of possible improvement. In this cross-sectional study we compared self-reported received and needed social support at the workplace of disease-free breast cancer survivors (BCSs) stage I from Norway and Finland. METHODS: Age-matched samples of 135 BCSs from Norway and 148 from Finland were examined using a questionnaire including socio-demographic factors, employment data, measurements of social support at work from supervisors, colleagues and the occupational health service (OHS), and several other measurements. RESULTS: Finnish BCSs had significantly higher education and a higher rate of full-time employment than Norwegian ones. With adjustment for education and work time, Finnish compared to Norwegian BCSs reported significantly less received social support from supervisors, while they received significantly more social support from OHS. No differences were observed in received support from colleagues between Finnish and Norwegian BCSs. Somatic health was most strongly associated with received and needed support from supervisors, colleagues and OHS. CONCLUSIONS: The differences in received and needed social support at work observed between Norwegian and Finnish BCSs treated for stage I disease challenge strengthening of OHS for Norwegian BCSs and increased attention by supervisors in Finnish BCSs.

Work engagement among breast cancer survivors and the referents: the importance of optimism and social resources at work.

INTRODUCTION: Despite a growing number of cancer survivors returning to work, little is known about their well-being at work and the work and personal characteristics related to it. The aim of the present study was to investigate personal resources (optimism and pessimism) and job-related resources (organizational climate, social support and avoidance behaviour) as antecedents of work engagement among female breast cancer survivors and their referents. METHODS: A community-based postal survey was conducted among female breast cancer survivors and their referents. The final study population consisted of 398 employed survivors (86% response rate) and 560 of their referents (71% response rate). RESULTS: The level of work engagement was high in both study groups, although it was slightly higher among the referents than among the cancer survivors (p < .05). Various social job resources were equally related to work engagement in both groups. However, optimism and pessimism were more strongly associated with work engagement among cancer survivors compared to the referents. In addition, in cancer survivors high optimism buffered against the negative impact of avoidance behaviour by supervisors on work engagement. CONCLUSIONS: Personal resources, such as optimism, may be especially important for cancer survivors' work-related well-being. On the other hand, social resources at work seem to be of similar salience to work engagement in cancer survivors and others. IMPLICATION FOR CANCER SURVIVORS: Understanding the role of job resources and personal resources appears to be important in efforts to increase a cancer survivors' commitment to work life even more so than in those working with a out breast cancer history.

Comparative study of work ability between cancer survivors and their referents.

Even though cancer survivors are often able to continue working after they have been diagnosed, they may have health impairments resulting in reduced work ability. We studied the current work ability of 591 employed people with an early-stage of breast cancer, lymphoma, testicular or prostate cancer, and 757 referents. We also investigated whether the survivors perceived that cancer had impaired their work ability, and which disease-related, socio-demographic and social factors at work had an impact on their work ability. The work ability of the cancer survivors did not differ from that of their referents. Among the survivors, 26% reported that their physical work ability, and 19% that their mental work ability had deteriorated due to cancer. The survivors who had other diseases or had had chemotherapy, most often reported impaired work ability, whereas survivors with a strong commitment to their work organisation, or a good social climate at work, reported impairment less frequently.

Occupational exposure in dentistry and miscarriage.

BACKGROUND: Information on the reproductive effects of chemical exposures in dental work is sparse or inconsistent. AIM: To investigate whether dental workers exposed to acrylate compounds, mercury amalgam, solvents or disinfectants are at an increased risk of miscarriage. METHODS: The study was conducted among women dental workers and a comparison group of workers occupationally unexposed to dental restorative materials. Information on pregnancies was obtained from national registers and outpatient units of hospitals. Data on occupational exposure were obtained using postal questionnaires. The final study population included 222 cases of miscarriage and 498 controls (births). An occupational hygienist assessed exposure to acrylate compounds, disinfectants and solvents. Exposure to other agents was assessed on the basis of the questionnaire data. Odds ratios (ORs) and confidence intervals (CIs) were estimated using conditional logistic regression. RESULTS: The ORs adjusted for confounding factors were increased for moderate-exposure and high-exposure categories of mercury amalgam (OR 2.0, 95% CI 1.0 to 4.1 and OR 1.3, 95% CI 0.6 to 2.5, respectively). The risk was slightly increased for the highest-exposure category of 2-hydroxyethylmethacrylate (OR 1.4, 95% CI 0.7 to 2.6) and polymethylmethacrylate dust (OR 1.4, 95% CI 0.8 to 2.4). A slightly increased risk was also detected for likely exposure to organic solvents (OR 1.4, 95% CI 0.8 to 2.3) and disinfectants (OR 1.5, 95% CI 0.9 to 2.7). CONCLUSIONS: No strong association or consistent dose-response relationship was observed between exposure to chemical agents in dental work and the risk of miscarriage. A slightly increased risk was found for exposure to mercury amalgam, some acrylate compounds, solvents and disinfectants. These findings indicate that the possibility of a weak association between exposure to these agents and an increased risk of miscarriage cannot be excluded.

Cancer in persons working in dry cleaning in the Nordic countries.

U.S. studies have reported an increased risk of esophageal and some other cancers in dry cleaners exposed to tetrachloroethylene. We investigated whether the U.S. findings could be reproduced in the Nordic countries using a series of case-control studies nested in cohorts of laundry and dry-cleaning workers identified from the 1970 censuses in Denmark, Norway, Sweden, and Finland. Dry-cleaning work in the Nordic countries during the period when tetrachloroethylene was the dominant solvent was not associated with an increased risk of esophageal cancer [rate ratio (RR) = 0.76; 95% confidence interval (CI), 0.34-1.69], but our study was hampered by some unclassifiable cases. The risks of cancer of the gastric cardia, liver, pancreas, and kidney and non-Hodgkin lymphoma were not significantly increased. Assistants in dry-cleaning shops had a borderline significant excess risk of cervical cancer not found in women directly involved in dry cleaning. We found an excess risk of bladder cancer (RR = 1.44; 95% CI, 1.07-1.93) not associated with length of employment. The finding of no excess risk of esophageal cancer in Nordic dry cleaners differs from U.S. findings. Chance, differences in level of exposure to tetrachloroethylene, and confounding may explain the findings. The overall evidence on bladder cancer in dry cleaners is equivocal.

Cancer survivors' received and needed social support from their work place and the occupational health services.

GOALS OF WORK: Even though a lot of studies have been conducted concerning cancer patients' social support, the importance of social support from the work life is unclear. We examined the amount of emotional and practical support that cancer survivors needed and had actually received from their coworkers, supervisors, and the occupational health personnel. We also examined whether disease-related or sociodemographic background variables were associated with needed or received support. Finally, we investigated whether there were differences between various sources in received or needed support. PATIENTS AND METHODS: The data consisted of a total of 640 cancer survivors with breast cancer, lymphoma, testicular or prostate cancer, aged 25-57 years at the time of diagnosis. Information on social support was collected with a mailed questionnaire using an adapted version of the Structural-Functional Social Support Scale (SFSS). MAIN RESULTS: The cancer survivors had received most support from their coworkers and they hoped for more support especially from the occupational health care personnel (39% of women and 29% of men). The men who had lymphoma, had received chemotherapy, or had low education level needed more support. The need for practical support from the occupational health personnel was fivefold between the chemotherapy-treated and those not treated. The women both received and needed more support than the men did. CONCLUSIONS: There is a clear need for additional social support from work life among the cancer survivors especially from the occupational health personnel.

Testicular cancer, occupation and exposure to chemical agents among Finnish men in 1971-1995.

OBJECTIVE: To find associations between testicular cancer, occupation and chemical exposure. METHODS: A cohort of all economically active Finnish men born between 1906 and 1945 was followed-up for 19.7 million person-years during 1971-1995. Incident cases of testicular cancer (n=387) were identified in a record linkage with the Finnish Cancer Registry. The Census occupations in 1970 were converted to chemical exposures with a job-exposure matrix (FINJEM). Cumulative exposure (CE) was calculated as the product of prevalence, level, and duration of the exposure. Standardised incidence ratio (SIR) was calculated for each of the 393 occupations, and for CE categories of the 43 chemical agents, using average male population as reference. Relative risks (RR) comparing various CE-categories with unexposed ones were defined for selected agents by Poisson regression analysis. RESULTS: Elevated SIRs were observed among railway traffic supervisors (5.8, 95% CI 1.6-14.7), programmers (4.3, 1.4-9.9), university teachers (4.1, 1.3-9.5) and electrical engineers (3.9, 1.1-10.1). A significant exposure-response trend (mainly contributed by seminoma) was observed for pesticides, textile dust, aliphatic and alicyclic hydrocarbons, and some other organic solvents. CONCLUSIONS: Risk of testicular cancer increased only in four occupations. Pesticides, textile dust, and some organic solvents may be related to an excess risk of seminoma.

National job-exposure matrix in analyses of census-based estimates of occupational cancer risk.

OBJECTIVES: The aim of this study was to increase the understanding of the alternative exposure metrics and analysis methods in studies applying job-exposure matrices in analyses of health outcomes, the association between crystalline silica and cancer being used as an example. METHODS: Observed and expected numbers of cancer cases during 1971-1995 among Finns born in 1906-1945 were calculated for 393 occupational categories, as defined in the 1970 population census. According to the Finnish Cancer Registry, there were 43 433 lung and 21 444 prostate cancer cases. The Finnish job-exposure matrix (FINJEM) provided estimates of the proportion of exposed persons and the mean level of exposure among the exposed in each occupation. RESULTS: The most comprehensive exposure metric included period- and age-specific estimates of exposure and an estimate of occupational stability, but also remarkably simpler metrics gave significantly elevated estimates of the risk ratio (RR) between 1.36 and 1.50 for lung cancer for occupations with the highest estimated cumulative silica exposure (> or = 10 mg/m3-years), allowing a lag time of 20 years. It proved important to adjust the risk ratios at least for the socioeconomic status and occupational exposure to asbestos. The risk ratios for prostate cancer were close to 1.0 in every model. CONCLUSIONS: The results showed that the FINJEM-based analysis was able to replicate the well-known association between exposure to crystalline silica and lung cancer. The FINJEM-based method gives valid results, and it can be used to analyze large sets of register-based data on health outcomes.

The impact of education and occupation on the employment status of cancer survivors.

We explored the effect of a diagnosis of cancer on employment according to cancer type, education, occupation, age, gender, mother tongue (Swedish or Finnish), calendar time and hospital district. All 12,542 new cancer cases diagnosed in 1987-1988 and 1992-1993, aged 15-60 years at the time of the diagnosis were identified from the Finnish Cancer Registry. The employment rate of the cancer survivors 2-3 years after the diagnosis was only 9% lower than their gender- and age-matched referents. However, we found that education and occupation modified the effect of cancer on the employment; the difference between cancer survivors and their referents in the probability of being employed was greater in the lower than in the higher educational groups. A modifying effect of education on the probability of employment was found among people with cancer of the lung, stomach, rectum and cervix uteri and those with cancers of the nervous system.