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A special issue of International Journal of Environmental Research and Public Health (ISSN 1660-4601). This special issue belongs to the section "Occupational Safety and Health".

Deadline for manuscript submissions: closed (31 October 2018) | Viewed by 48626

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Dr. Marit Skogstad

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Guest Editor

National Institute of Occupational Health (STAMI), Box 5330 Majorstuen, 0304 Oslo, Norway
Interests: epidemiology and occupational health; lung; cardiology; hyperbaric medicine
Special Issues, Collections and Topics in MDPI journals

Dr. Øivind Skare

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Department Occupational Medicine and Epidemiology, National Institute of Occupational Health, Box 8149 Dep., 0033 Oslo, Norway
Interests: epidemiology; biostatistics; longitudinal data analysis; exposure modelling

Special Issue Information

Dear Colleagues,

We are organizing a Special Issue on “Occupational Epidemiology” in the International Journal of Environmental Research and Public Health. The venue is a peer-reviewed scientific journal that publishes articles and communications in the interdisciplinary area of environmental health sciences and public health. For detailed information on the journal, we refer you to https://www.mdpi.com/journal/ijerph.

In times of globalization, movements of workforce, outsourcing of hazardous work from developed to developing countries, labor law differences between countries but also new technology put new challenges into the field of occupational epidemiology. Analyzing the impact of these changes is, therefore, a topic of high relevance to science, as well as to policy. Considerable advances in the availability of large data sets from epidemiological cohort studies and international working networks have been established. There are still many gaps of knowledge, e.g., concerning health outcomes due to hazardous exposure in the workplaces.

With this Special Issue, we invite you to submit high-quality original research articles or reviews that provide solid new findings extending the current state of knowledge. Preference will be given to contributions using longitudinal data. Studies with cross-sectional design will only be considered as exceptions if convincingly justified. All manuscripts will be peer-reviewed by experts in the field, and would be due no later than the end of October 2018.

Dr. Marit Skogstad
Dr. Øivind Skare
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Environmental Research and Public Health is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2500 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

Cohort studies
Occupational medicine
Studies, epidemiologic
Lung diseases
Skin diseases
Cardiovascular diseases
Central nervous system diseases
Hearing disorders
Occupational exposures (chemical, physical, biological)

Published Papers (11 papers)

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Research

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11 pages, 325 KiB

Open AccessArticle

Shift Work Including Night Work and Long Working Hours in Industrial Plants Increases the Risk of Atherosclerosis

by Marit Skogstad, Asgeir Mamen, Lars-Kristian Lunde, Bente Ulvestad, Dagfinn Matre, Hans Christian D. Aass, Reidun Øvstebø, Pia Nielsen, Kari N. Samuelsen, Øivind Skare and Per Anton Sirnes

Int. J. Environ. Res. Public Health 2019, 16(3), 521; https://doi.org/10.3390/ijerph16030521 - 12 Feb 2019

Cited by 40 | Viewed by 6068

Abstract

There is an abundance of literature reporting an association between shift work and cardiovascular disease (CVD). Few studies have examined early manifestation of CVD using advanced modern methodology. We established a group of 65 shift workers and 29 day workers (controls) in two industrial plants. For the shift workers, the shift schedule includes rotating shifts with day, evening and nightshifts, some day and nightshifts lasting for 12 h. The current paper describes cross-sectional data in a study running for three years. We collected background data by questionnaire and measured blood pressure, heart rate, lipids, glycosylated hemoglobin (HbA1c) and C-reactive protein (CRP). We examined arterial stiffness (central blood pressure, augmentation pressure and index, and pulse wave velocity) by the use of SphygmoCor^® (AtCor Medical Pty Ltd, Sydney, Australia) and the carotid arteries by ultrasound. We assessed VO_2max by bicycle ergometry. We applied linear and logistic regression to evaluate associations between total number of years in shift work and cardiovascular outcome measures. The day workers were older and had more pronounced arterial stiffness compared to the shift workers. Number of years as a shift worker was associated with increased carotid intima media thickness (max IMT) (B = 0.015, p = 0.009) and an elevated CRP (B = 0.06, p = 0.03). Within the normal range for this age group, VO_2max was 41 (9) ml/kg/min. Rotating shift work including day and night shifts lasting up to 12 h and evening shifts are associated with CVD-risk factors. This could imply an increased risk for coronary heart disease and stroke among these workers. Therefore, preventive measures should be considered for these groups of workers in order to prevent such diseases. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

13 pages, 2272 KiB

Open AccessArticle

Characteristics and Trends of Pneumoconiosis in the Jiangsu Province, China, 2006–2017

by Lei Han, Wenxi Yao, Zilong Bian, Yuan Zhao, Hengdong Zhang, Bangmei Ding, Han Shen, Ping Li, Baoli Zhu and Chunhui Ni

Int. J. Environ. Res. Public Health 2019, 16(3), 437; https://doi.org/10.3390/ijerph16030437 - 02 Feb 2019

Cited by 23 | Viewed by 4482

Abstract

This study aims to describe the characteristics and trends of pneumoconiosis in the Jiangsu Province, China, and provide information for the occupational diseases control. We collected and analyzed the data of pneumoconiosis cases reported annually from 2006 to 2017. The information of the cases mainly includes case distributions, clinical types and stages, enterprise types and scales, as well as diagnosis age and exposure duration. A total of 9243 pneumoconiosis cases were reported between 2006 and 2017, among which silicosis and coal workers’ pneumoconiosis accounted for the vast majority (87.5%). The incidence of pneumoconiosis was relatively higher in Wuxi, Yancheng, Suzhou and Xuzhou, compared to the other district. Most pneumoconiosis cases occurred in the state-owned (58.4%) and collective enterprises (23.8%). Most cases worked in industries related to geology and coal production. The median exposure duration and diagnosis age of the total pneumoconiosis cases was 13.2 and 61.0 years, respectively. Therefore, more measurements are needed to control pneumoconiosis in the Jiangsu Province. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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11 pages, 1375 KiB

Open AccessArticle

Pneumoproteins in Offshore Drill Floor Workers

by Niels E. Kirkhus, Bente Ulvestad, Lars Barregard, Øivind Skare, Raymond Olsen, Yngvar Thomassen and Dag G. Ellingsen

Int. J. Environ. Res. Public Health 2019, 16(3), 300; https://doi.org/10.3390/ijerph16030300 - 23 Jan 2019

Cited by 6 | Viewed by 2406

Abstract

The aim was to assess pneumoproteins and a certain biomarker of systemic inflammation in drill floor workers exposed to airborne contaminants generated during drilling offshore, taking into consideration serum biomarkers of smoking, such as nicotine (S-Nico) and cotinine. Blood samples of club cell protein 16 (CC-16), surfactant protein D (SP-D) and C-reactive protein (CRP) were collected before and after a 14-day work period from 65 drill floor workers and 65 referents. Air samples of oil mist, drilling mud components and elemental carbon were collected in person. The drill floor workers were exposed to a median air concentration of 0.18 mg/m³ of oil mist and 0.14 mg/m³ of airborne mud particles. There were no differences in the concentrations of CC-16 and SP-D across the 14-day work period and no difference between drill floor workers and referents at baseline after adjusting for differences in sampling time and smoking. CRP decreased across the work period. There was a strong association between the CC-16 concentrations and the time of sampling. Current smokers with S-Nico > detection limit (DL) had a statistically significantly lower CC-16 concentration, while smokers with S-Nico < DL had CC-16 concentrations similar to that of the non-smokers. Fourteen days of work offshore had no effect on serum pneumoprotein and CRP concentrations. However, the time of blood sampling was observed to have a strong effect on the measured concentrations of CC-16. The effect of current smoking on the CC-16 concentrations appears to be dependent on the S-Nico concentrations. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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23 pages, 5188 KiB

Open AccessArticle

Variation in Nordic Work-Related Cancer Risks after Adjustment for Alcohol and Tobacco

by Kristina Kjaerheim, Tor Haldorsen, Elsebeth Lynge, Jan Ivar Martinsen, Eero Pukkala, Elisabete Weiderpass and Tom K. Grimsrud

Int. J. Environ. Res. Public Health 2018, 15(12), 2760; https://doi.org/10.3390/ijerph15122760 - 06 Dec 2018

Cited by 8 | Viewed by 3615

Abstract

Background: Alcohol and tobacco strongly increases the risk of cancers of the tongue, mouth, pharynx, larynx, and oesophagus, and are also established risk factors for cancer of the liver, colon, and rectum. It is well documented that these habits are unequally distributed among occupational groups. Most occupational cohort studies lack information on these potentially important confounders, and may therefore be prone to bias. Aim: The aim of the study is to present Nordic standardized incidence ratios (SIRs) for alcohol and tobacco related cancer by occupation, after adjustment for alcohol and tobacco, and to compare to the unadjusted SIRs. Material and Methods: The study is based on the Nordic Occupational Cancer (NOCCA) database. We used confirmatory factor analysis models for simultaneous analysis of the cancer sites related to alcohol and tobacco, to obtain factors that allow for computation of adjusted expected numbers from the reference rates. We then calculated adjusted SIRs for the relevant cancer sites for each occupation. Results: For some occupations and cancers, the changes of risk estimates were striking, from significantly high to significantly low and vice versa. Among Nordic farmers, unadjusted SIRs for cancer of the mouth and oesophagus were 0.56 (95% confidence interval (CI) 0.51–0.61) and 0.67 (CI 0.63–0.70), respectively. After adjustment, estimates changed to 1.10 (CI 1.01–1.21) and 1.16 (CI 1.10–1.22). Unadjusted SIR for pharynx cancer among wood workers was 0.83 (CI 0.75–0.91), adjusted SIR was 1.14 (CI 1.03–1.25). For larynx cancer, results in the opposite direction were seen: unadjusted SIR for economically inactive was 1.38 (CI 1.31–1.46) while the adjusted SIR was 0.91 (CI 0.86–0.96). Conclusions: Adjustment for the latent indicators of alcohol and tobacco consumption changed risk estimates for several occupations, gave a less confounded description of risk, and may guide in the identification of true risk factors. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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10 pages, 1844 KiB

Open AccessArticle

Tuberculosis Mortality by Occupation in South Africa, 2011–2015

by Tahira Kootbodien, Kerry Wilson, Nonhlanhla Tlotleng, Vusi Ntlebi, Felix Made, David Rees and Nisha Naicker

Int. J. Environ. Res. Public Health 2018, 15(12), 2756; https://doi.org/10.3390/ijerph15122756 - 05 Dec 2018

Cited by 14 | Viewed by 3974

Abstract

Work-related tuberculosis (TB) remains a public health concern in low- and middle-income countries. The use of vital registration data for monitoring TB deaths by occupation has been unexplored in South Africa. Using underlying cause of death and occupation data for 2011 to 2015 from Statistics South Africa, age-standardised mortality rates (ASMRs) were calculated for all persons of working age (15 to 64 years) by the direct method using the World Health Organization (WHO) standard population. Multivariate logistic regression analysis was performed to calculate mortality odds ratios (MORs) for occupation groups, adjusting for age, sex, year of death, province of death, and smoking status. Of the 221,058 deaths recorded with occupation data, 13% were due to TB. ASMR for TB mortality decreased from 165.9 to 88.8 per 100,000 population from 2011 to 2015. An increased risk of death by TB was observed among elementary occupations: agricultural labourers (MOR_adj = 3.58, 95% Confidence Interval (CI) 2.96–4.32), cleaners (MOR_adj = 3.44, 95% CI 2.91–4.09), and refuse workers (MOR_adj = 3.41, 95% CI 2.88–4.03); among workers exposed to silica dust (MOR_adj = 3.37, 95% CI 2.83–4.02); and among skilled agricultural workers (MOR_adj = 3.31, 95% CI 2.65–4.19). High-risk TB occupations can be identified from mortality data. Therefore, TB prevention and treatment policies should be prioritised in these occupations. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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12 pages, 757 KiB

Open AccessArticle

Infections in Healthcare Workers in Germany—22-Year Time Trends

by Albert Nienhaus

Int. J. Environ. Res. Public Health 2018, 15(12), 2656; https://doi.org/10.3390/ijerph15122656 - 26 Nov 2018

Cited by 14 | Viewed by 4214

Abstract

Health workers (HWs) run an increased risk of infection. The standardised data set of an accident insurer was used to analyse the time trends of infection-related claims and confirmed occupational diseases (ODs) in HWs. The numbers of claims and confirmed claims for different infections were analysed for the years 1996 to 2017. The rate of claims and confirmed ODs were calculated per 100,000 full-time workers. The number of claims was relatively stable over time. However, the rate per 100,000 full-time workers decreased from 25.2 to 15.4. The decrease was most pronounced for hepatitis B and hepatitis C infections, which were the most frequent infections for which claims were made at the start of the period. In 2017, tuberculosis (TB)-related claims were more frequent than those related to blood-borne virus infections. However, the growing number of TB claims does not reflect an increased infection risk, but rather improved methods for the diagnosis of latent TB infection (LTBI). Measures to prevent blood-borne virus infections in HWs were successful in the last 22 years, but attention should be paid to newly emerging infections. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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9 pages, 536 KiB

Open AccessArticle

Use of Non-Steroidal Anti-Inflammatory Drugs and Associated Gastroprotection in a Cohort of Workers

by María Jesús Lallana, Cristina Feja, Isabel Aguilar-Palacio, Sara Malo and María José Rabanaque

Int. J. Environ. Res. Public Health 2018, 15(9), 1836; https://doi.org/10.3390/ijerph15091836 - 24 Aug 2018

Cited by 6 | Viewed by 3154

Abstract

Background: This study describes the prevalence of non-steroidal anti-inflammatory drug (NSAID) use, and analyses prescribing patterns of NSAIDs and associated gastroprotection. Methods: The study population consisted of 5650 workers at the General Motors automobile assembly plant in Zaragoza, Spain. NSAID prescription data for 2014 were obtained from the prescription database of Aragon (Spain). NSAID consumption was determined based on the number of defined daily doses purchased per year. Heavy NSAIDs users were identified using Lorenz curves. Results: NSAID use in the cohort was high (40.7% of workers, 95% CI 39.4–41.9). The prescription of proton pump inhibitors increased with age. Gastrointestinal protection was lacking in some participants who were being treated with drugs associated with a high risk of gastrointestinal bleeding. Heavy NSAID users (defined as those above the 95th percentile of consumption), accounted for 26% of total DDDs, and consumed a greater proportion of coxibs than non-heavy users. Conclusions: The rate of NSAID consumption in the cohort was high. To reduce the risk of gastrointestinal complications, monitoring and adequate gastroprotection are essential in patients who are prescribed NSAIDs for long periods of time or who are treated concomitantly with drugs that increase the risk of gastrointestinal bleeding. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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20 pages, 3682 KiB

Open AccessArticle

Dietary Differences in Male Workers among Smaller Occupational Groups within Large Occupational Categories: Findings from the Japan Environment and Children’s Study (JECS)

by Rie Tanaka, Mayumi Tsuji, Ayako Senju, Koichi Kusuhara, Toshihiro Kawamoto and Japan Environment and Children’s Study Group

Int. J. Environ. Res. Public Health 2018, 15(5), 961; https://doi.org/10.3390/ijerph15050961 - 11 May 2018

Cited by 5 | Viewed by 3352

Abstract

Studies examining workers’ diet according to smaller occupational groups within “large occupational categories” are sparse. The aim of this study was to examine the potential differences in workers’ diets based on the classification of workers into smaller occupational groups that comprise “large occupational categories”. The subjects of this study were working fathers who had participated in the Japan Environment and Children’s Study (N = 38,656). Energy and nutrient intake were calculated based on data collected from the Food Frequency Questionnaire. Occupations were classified according to the Japanese Standard Occupational Classification. Logistic regression analyses were performed to examine the adherence to current dietary recommendations within smaller occupational groups. In particular, significant differences were observed among the categorical groups of “professional and engineering workers”, “service workers”, and “agricultural, forestry, and fishery workers”. In “professional and engineering workers”, teachers showed higher odds of adherence to calcium intake recommendations compared with nurses (OR, 2.54; 95% CI, 2.02–3.14; p < 0.001). In “agricultural, forestry, and fishery workers”, agriculture workers showed higher odds of adherence to calcium (OR, 2.15; 95% CI, 1.46–3.15; p < 0.001) and vitamin C (OR 1.90, 95% CI 1.31–2.74, p = 0.001) intake recommendations compared with forestry and fishery workers. These findings may be beneficial from a research perspective as well as in the development of more effective techniques to improve workers’ diet and health. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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Review

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17 pages, 2352 KiB

Open AccessReview

Occupational Exposures and Neurodegenerative Diseases—A Systematic Literature Review and Meta-Analyses

by Lars-Gunnar Gunnarsson and Lennart Bodin

Int. J. Environ. Res. Public Health 2019, 16(3), 337; https://doi.org/10.3390/ijerph16030337 - 26 Jan 2019

Cited by 95 | Viewed by 8580

Abstract

Objectives: To carry out an integrated and stratified meta-analysis on occupational exposure to electromagnetic fields (EMFs), metals and pesticides and its effects on amyotrophic lateral sclerosis (ALS) and Parkinson’s and Alzheimer’s disease, and investigate the possibility of publication bias. Methods: In the current study, we updated our recently published meta-analyses on occupational exposures in relation to ALS, Alzheimer’s and Parkinson’s disease. Based on 66 original publications of good scientific epidemiological standard, according to the Meta-analysis of Observational Studies in Epidemiology (MOOSE) and the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) guidelines, we analysed subgroups by carrying out stratified meta-analyses on publication year, statistical precision of the relative risk (RR) estimates, inspection of the funnel plots and test of bias. Results: Based on 19 studies the weighted RR for occupational exposure to EMFs was 1.26 (95% confidence interval (CI) 1.07–1.50) for ALS, 1.33 (95% CI 1.07–1.64) for Alzheimer’s disease and 1.02 (95% CI 0.83–1.26) for Parkinson’s disease. Thirty-one studies concerned occupational exposure to pesticides and the weighted RR was 1.35 (95% CI 1.02–1.79) for ALS, 1.50 (95% CI 0.98–2.29) for Alzheimer’s disease and 1.66 (95% CI 1.42–1.94) for Parkinson’s disease. Finally, 14 studies concerned occupational exposure to metals and only exposure to lead (five studies) involved an elevated risk for ALS or Parkinson’s disease and the weighted RR was 1.57 (95% CI 1.11–2.20). The weighted RR for all the non-lead exposures was 0.97 (95% CI 0.88–1.06). Conclusions: Exposure to pesticides increased the risk of getting the mentioned neurodegenerative diseases by at least 50%. Exposure to lead was only studied for ALS and Parkinson’s disease and involved 50% increased risk. Occupational exposure to EMFs seemed to involve some 10% increase in risk for ALS and Alzheimer’s disease only. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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16 pages, 1393 KiB

Open AccessReview

Hip Osteoarthritis and Physical Workload: Influence of Study Quality on Risk Estimations—A Meta-Analysis of Epidemiological Findings

by Yi Sun, Annette Nold, Ulrich Glitsch and Frank Bochmann

Int. J. Environ. Res. Public Health 2019, 16(3), 322; https://doi.org/10.3390/ijerph16030322 - 24 Jan 2019

Cited by 3 | Viewed by 2834

Abstract

In this paper, we critically evaluate the quality of epidemiological evidence on hip osteoarthritis and workload published so far. The influence of study quality on risk estimations was analyzed in sensitivity meta-analyses and meta-regression analyses. Comprehensive searches for epidemiological studies of hip osteoarthritis and occupational workload were performed in literature databases and current reviews. All studies were assessed on the basis of study design, defined quality scores, and relevant confounders considered. In total, 34 suitable studies were identified for critical evaluation. Of these, 20 are prevalence studies and 14 incidence studies. Strong heterogeneity is observed in study design, quality level, and estimated exposure parameters. A consistent positive association between heavy physical workload and hip osteoarthritis was observed only among the male populations, not among the female populations. In general, cohort studies provided lower effect estimates than cross-sectional and population-based case-control studies. Studies with high quality scores also produced lower effect estimates than studies with low quality scores. Consideration of BMI as a confounder in published studies also yielded lower effect estimates than studies without consideration of BMI as a confounder. Our analyses indicate that high-quality studies of the association between occupational workload and hip osteoarthritis provide lower effect estimates than studies of lower quality. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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21 pages, 3140 KiB

Open AccessReview

Amyotrophic Lateral Sclerosis and Occupational Exposures: A Systematic Literature Review and Meta-Analyses

by Lars-Gunnar Gunnarsson and Lennart Bodin

Int. J. Environ. Res. Public Health 2018, 15(11), 2371; https://doi.org/10.3390/ijerph15112371 - 26 Oct 2018

Cited by 37 | Viewed by 4872

Abstract

Objectives: We conducted a systematic literature review to identify studies fulfilling good scientific epidemiological standards for use in meta-analyses of occupational risk factors for amyotrophic lateral sclerosis (ALS). Methods: We identified 79 original publications on associations between work and ALS. The MOOSE (Meta-analysis Of Observational Studies in Epidemiology) and GRADE (Grading of Recommendations, Assessment, Development and Evaluations) guidelines were used to ensure high scientific quality, and reliable protocols were applied to classify the articles. Thirty-seven articles fulfilled good scientific standards, while 42 were methodologically deficient and thus were excluded from our meta-analyses. Results: The weighted relative risks for the various occupational exposures were respectively; 1.29 (95% confidence interval (CI): 0.97–1.72; six articles) for heavy physical work, 3.98 (95% CI: 2.04–7.77; three articles) for professional sports, 1.45 (95% CI: 1.07–1.96; six articles) for metals, 1.19 (95% CI: 1.07–1.33; 10 articles) for chemicals, 1.18 (95% CI: 1.07–1.31; 16 articles) for electromagnetic fields or working with electricity, and 1.18 (95% CI: 1.05–1.34; four articles) for working as a nurse or physician. Conclusions: Meta-analyses based only on epidemiologic publications of good scientific quality show that the risk of ALS is statistically significantly elevated for occupational exposures to excessive physical work, chemicals (especially pesticides), metals (especially lead), and possibly also to electromagnetic fields and health care work. These results are not explained by publication bias. Full article

(This article belongs to the Special Issue Occupational Epidemiology)

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