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Quecke E, Quemerais B, Hashisho Z. Review of welding fume emission factor development. Ann Work Expo Health 2023; 67:675-693. [PMID: 37191647 DOI: 10.1093/annweh/wxad024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 04/18/2023] [Indexed: 05/17/2023] Open
Abstract
The fumes created from welding activities present a unique occupational hazard. Due to the complex processes which govern fume formation, the characterization of welding fumes is difficult. Emission factors (EFs) are one method to characterize fume formation from different processes and scenarios. This paper reviews the development of EFs and similar metrics both historic research which contributed to the US EPAs AP-42 summary of welding emission factors released in 1995, and more recent research initiatives. Through a critical analysis of what research has been done in this area and the strength of the emission factors developed, this paper proposes a set of recommendations for future research. Research on emission factors for gas metal arc welding (GMAW) is the most complete amongst the different types of electric arc welding. Despite it being generally known that flux core arc welding (FCAW) creates significant fume emissions compared to some of the other processes few studies have looked at FCAW since the AP-42. Shielded metal arc welding is also under-researched particularly in terms of metal-specific emission factors. The influence of different welding activity parameters such as welding location, speed or current is well defined for GMAW but requires more attention for other welding processes. Further effort towards compiling and comparing available emission factor data of quality, evaluating the available data statistically and organizing this data in a practically useful way is required. The availability of reliable emission factors will allow the development or improvement of exposure modelling tools that would be very useful for exposure assessment when monitoring is not practical.s.
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Affiliation(s)
- Emily Quecke
- Faculty of Engineering, Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6R 2W2, Canada
| | - Bernadette Quemerais
- Faculty of Medicine and Dentistry, Department of Medicine, University of Alberta, Edmonton, AB, T6R 2R3, Canada
| | - Zaher Hashisho
- Faculty of Engineering, Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6R 2W2, Canada
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Ahmadi S, Guth M, Coste A, Bouaoun L, Danjou A, Lefevre M, Dananché B, Praud D, Van Tongeren M, Bujan L, Pérol O, Schüz J, Charbotel B, Fervers B, Olsson A. Paternal Occupational Exposure to Heavy Metals and Welding Fumes and Testicular Germ Cell Tumours in Sons in France. Cancers (Basel) 2022; 14:4962. [PMID: 36230885 PMCID: PMC9564333 DOI: 10.3390/cancers14194962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 09/28/2022] [Accepted: 10/05/2022] [Indexed: 11/16/2022] Open
Abstract
Testicular cancer is the most common cancer in young men. Its causes are largely unknown, although prenatal occupational and environmental exposures have been suggested. We investigated paternal occupational exposure to heavy metals and welding fumes and the risk of testicular germ cell tumors (TGCT) in their offspring. A total of 454 cases and 670 controls were included from a French nationwide case-control study. The INTEROCC job exposure matrix was used to assign occupational exposures (cadmium, chromium, iron, nickel, lead, and welding fumes) to the fathers' jobs. Odds ratios (ORs) for TGCT were estimated using conditional logistic regression models for frequency-matched sets. Three complementary analytical approaches were used: (1) single-agent analysis, (2) analysis by groups, and (3) principal component analysis (PCA). The proportion of paternal exposure to different heavy metals and welding fumes ranged from 0.7% (cadmium) to 11.3% (lead). Based on PCA, three principal components explained 93.5% of the cumulative variance. No associations were found between heavy metals or welding fumes and TGCT. In this study, paternal occupational exposure to heavy metals or welding fumes was not associated with TGCT development in their sons.
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Affiliation(s)
- Shukrullah Ahmadi
- Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer IARC/WHO, 150 cours Albert Thomas, CEDEX 08, 69372 Lyon, France
| | - Margot Guth
- UMRESTTE, UMR T 9405, IFSTTAR, Lyon 1 University, Eiffel University, 69008 Lyon, France
| | - Astrid Coste
- Département Prévention, Cancer et Environnement, Centre Léon Bérard, 69008 Lyon, France
- INSERM UMR1296 Radiation: Defense, Health, Environment, 69008 Lyon, France
| | - Liacine Bouaoun
- Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer IARC/WHO, 150 cours Albert Thomas, CEDEX 08, 69372 Lyon, France
| | - Aurélie Danjou
- Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer IARC/WHO, 150 cours Albert Thomas, CEDEX 08, 69372 Lyon, France
| | - Marie Lefevre
- UMRESTTE, UMR T 9405, IFSTTAR, Lyon 1 University, Eiffel University, 69008 Lyon, France
| | - Brigitte Dananché
- INSERM UMR1296 Radiation: Defense, Health, Environment, 69008 Lyon, France
| | - Delphine Praud
- Département Prévention, Cancer et Environnement, Centre Léon Bérard, 69008 Lyon, France
- INSERM UMR1296 Radiation: Defense, Health, Environment, 69008 Lyon, France
| | - Martie Van Tongeren
- Centre for Human Exposure Science, Institute of Occupational Medicine (IOM), Research Avenue North, Riccarton, Edinburgh EH14 4AP, UK
| | - Louis Bujan
- DEFE (Développement Embryonnaire, Fertilité, Environnement) INSERM 1203, Universités Montpellier et Toulouse 3, 31000 Toulouse, France
- CECOS Hôpital Paule de Viguier, CHU de Toulouse, 31059 Toulouse, France
- Fédération Française des CECOS, 75014 Paris, France
| | - Olivia Pérol
- Département Prévention, Cancer et Environnement, Centre Léon Bérard, 69008 Lyon, France
- INSERM UMR1296 Radiation: Defense, Health, Environment, 69008 Lyon, France
| | - Joachim Schüz
- Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer IARC/WHO, 150 cours Albert Thomas, CEDEX 08, 69372 Lyon, France
| | - Barbara Charbotel
- UMRESTTE, UMR T 9405, IFSTTAR, Lyon 1 University, Eiffel University, 69008 Lyon, France
| | - Béatrice Fervers
- Département Prévention, Cancer et Environnement, Centre Léon Bérard, 69008 Lyon, France
- INSERM UMR1296 Radiation: Defense, Health, Environment, 69008 Lyon, France
| | - Ann Olsson
- Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer IARC/WHO, 150 cours Albert Thomas, CEDEX 08, 69372 Lyon, France
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Lucas D, Guerrero F, Jouve E, Hery S, Capellmann P, Mansourati J. Effect of occupational exposure to welding fumes and noise on heart rate variability: An exposed-unexposed study on welders and airport workers' population. Front Public Health 2022; 10:937774. [PMID: 36249234 PMCID: PMC9554501 DOI: 10.3389/fpubh.2022.937774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 09/07/2022] [Indexed: 01/25/2023] Open
Abstract
Introduction Welding fumes (WF) are a complex mixture of gas and particles. Action of occupational exposure to WF on cardiovascular system has been recently studied as for noise. Research question The main objectives of our study are therefore to evaluate the impact of exposure to WF, noise, and combined WF and noise on autonomic nervous system as assessed by heart rate variability (HRV). Methods The study groups were 16 welders and eight airport workers (as a control group). All the participants underwent ambulatory electrocardiogram, personal WF, and noise exposure monitoring, respectively, with dust track and calibrated noise dosimeter during workday. Atmospheric environmental assessments at workplaces have been also performed. HRV parameters were summarized for all the workday and hourly. Correlation tests were used to examine relation between HRV parameters and levels of noise exposure in the two population. Analysis of covariance (ANCOVA) was used for mean of each HRV parameters. Results For HRV parameters, we found significant higher levels for mean range of high frequency (HF), standard deviation of normal-to-normal R-R interval (SDNN), and root mean square of successive heartbeat interval difference (RMSSD) in welders which suggested an imbalance between sympathetic and parasympathetic nervous system in this population. For relation between noise and HRV parameters, we noted that levels of low frequency (LF), HF, and SDNN were significantly correlated with mean noise levels for welders (respectively, r = 0.62, r = 0.357, r = 0.48), not in control group. Using ANCOVA, we found that working as a welder significantly increases mean of HF (p = 0.01) and RMSSD (p = 0.02) and decreases in LF/HF (p = 0.008). Indeed, the interaction between exposure to WF and mean noise levels for HF (p = 0.005), LF/HF (p = 0.01), and RMSSD (p = 0.007) was significant. Conclusion This study shows an impact of WF and noise on ANS balance. One hypothesis is WF exposure could increase sensibility to noise exposure on autonomic nervous system or there is a synergic effect.
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Affiliation(s)
- David Lucas
- Center of Environmental and Occupational Diseases, Department of Occupational Health, Brest Teaching Hospital, Brest, France,ORPHY Laboratory, Department of Sciences, Occidental Brittany University Brest, Brest, France,*Correspondence: David Lucas
| | - François Guerrero
- ORPHY Laboratory, Department of Sciences, Occidental Brittany University Brest, Brest, France
| | - Emmanuel Jouve
- Carsat Bretagne (Regional Agency of Occupational Health), Department of Occupational Prevention, Rennes, France
| | - Sophie Hery
- Occupational Health Service, Department of Occupational Prevention, Naval Group, Brest, France
| | - Pascale Capellmann
- Iroise Occupational Health Service, Department of Occupational Prevention 22 Rue de Kervezennec, Brest, France
| | - Jacques Mansourati
- ORPHY Laboratory, Department of Sciences, Occidental Brittany University Brest, Brest, France,Cardiology Unit, Department of Cardiovascular Diseases, Brest Teaching Hospital, Brest, France
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Li G, Jiang J, Liao Y, Wan S, Yao Y, Luo Y, Chen X, Qian H, Dai X, Yin W, Min Z, Yi G, Tan X. Risk for lung-related diseases associated with welding fumes in an occupational population: Evidence from a Cox model. Front Public Health 2022; 10:990547. [PMID: 36091502 PMCID: PMC9455702 DOI: 10.3389/fpubh.2022.990547] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Accepted: 08/09/2022] [Indexed: 01/26/2023] Open
Abstract
Background Welding fumes are a risk factor for welder pneumoconiosis. However, there is a lack of population information on the occurrence of welding fume-induced lung cancer, and little is known about the welding fume pathogenesis. Methods Welding fume and metal ion concentrations were assessed in a vehicle factory in Wuhan. A Cox regression model estimated lung-related disease risk in workers by independent and combined factors. Results Workers' exposures were divided into four grades; the highest exposure was among the welders in the maintenance workshop, the highest Mn and Fe exposure was 4 grades, and the highest Cr exposure was 3 grades. Subgroup analysis found that the risk of lung-related disease was 2.17 (95% CI: 1.31-3.57, p < 0.05) in welders compared with non-welders, and the risk of pulmonary disease in male welders was 2.24 (95% CI: 1.34-3.73, p < 0.05) compared to non-welders. Smoking welders had a 2.44 (95% CI: 1.32-4.51, p < 0.01) higher incidence of lung-related diseases than non-welders. Total years of work as an independent protective factor for lung-related disease risk was 0.72 (95% CI: 0.66-0.78, p < 0.01). As an independent risk factor, high-high and high-low exposure had a 5.39 (95% CI: 2.52-11.52, p < 0.001) and 2.17 (95% CI: 1.07-4.41, p < 0.05) higher risk for lung-related diseases, respectively. Conclusions High welding fume exposure is a significant risk factor for lung-related disease in workers.
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Affiliation(s)
- Guangming Li
- Department of Preventive Medicine, School of Public Health, Wuhan University, Wuhan, China
| | - Jinfeng Jiang
- Wuhan Prevention and Treatment Center for Occupational Diseases, Wuhan, China
| | - Yonggang Liao
- Wuhan Prevention and Treatment Center for Occupational Diseases, Wuhan, China
| | - Siyu Wan
- Wuhan Prevention and Treatment Center for Occupational Diseases, Wuhan, China
| | - Yong Yao
- Wuhan Prevention and Treatment Center for Occupational Diseases, Wuhan, China
| | - Yongbin Luo
- Wuhan Prevention and Treatment Center for Occupational Diseases, Wuhan, China
| | - Xuyu Chen
- Department of Preventive Medicine, School of Public Health, Wuhan University, Wuhan, China
| | - Huiling Qian
- Department of Preventive Medicine, School of Public Health, Wuhan University, Wuhan, China
| | - Xiayun Dai
- Wuhan Prevention and Treatment Center for Occupational Diseases, Wuhan, China
| | - Wenjun Yin
- Wuhan Prevention and Treatment Center for Occupational Diseases, Wuhan, China
| | - Zhiteng Min
- Wuhan Prevention and Treatment Center for Occupational Diseases, Wuhan, China
| | - Guilin Yi
- Wuhan Prevention and Treatment Center for Occupational Diseases, Wuhan, China,Guilin Yi
| | - Xiaodong Tan
- Department of Preventive Medicine, School of Public Health, Wuhan University, Wuhan, China,School of Health and Nurse, Wuchang University of Technology, Wuhan, China,*Correspondence: Xiaodong Tan
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Krabbe J, Kraus T, Krabbe H, Martin C, Ziegler P. Welding Fume Instillation in Isolated Perfused Mouse Lungs-Effects of Zinc- and Copper-Containing Welding Fumes. Int J Mol Sci 2022; 23:ijms23169052. [PMID: 36012318 PMCID: PMC9408907 DOI: 10.3390/ijms23169052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 11/16/2022] Open
Abstract
Zinc- and copper-containing welding fumes can cause systemic inflammation after exposure in humans. Recent ex vivo studies have shown that the observed inflammation originates from exposed immune cells. In vitro studies identified the soluble fraction of metal particles as the main effectors. Isolated perfused mouse lungs (IPLs) were perfused and ventilated for 270 min. Lungs were instilled with saline solution (control), welding fume particle suspension (WFs) or the soluble fraction of the welding fumes (SF-WFs). Bronchoalveolar lavage fluid (BALF) and perfusate samples were analyzed for cytokine levels and lung tissue mRNA expression levels were analyzed via RT-PCR. All lungs instilled with WFs did not complete the experiments due to a fatal reduction in tidal volume. Accordingly, IL-6 and MPO levels were significantly higher in BALF of WF lungs compared to the control. IL-6 and MPO mRNA expression levels were also increased for WFs. Lungs instilled with SF-WFs only showed mild reactions in tidal volume, with BALF and mRNA expression levels not significantly differing from the control. Zinc- and copper-containing welding fume particles adversely affect IPLs when instilled, as evidenced by the fatal loss in tidal volume and increased cytokine expression and secretion. The effects are mainly caused by the particles, not by the soluble fraction.
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Affiliation(s)
- Julia Krabbe
- Institute of Occupational, Social and Environmental Medicine, Medical Faculty, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
- Correspondence: ; Tel.: +49-241-8035028; Fax: +49-241-8082587
| | - Thomas Kraus
- Institute of Occupational, Social and Environmental Medicine, Medical Faculty, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Hanif Krabbe
- European Vascular Centre Aachen-Maastricht, Department of Vascular Surgery, Medical Faculty, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Christian Martin
- Institute of Pharmacology and Toxicology, Medical Faculty, RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
| | - Patrick Ziegler
- Institute of Occupational, Social and Environmental Medicine, Medical Faculty, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
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Olsson A, Kromhout H. Occupational cancer burden: the contribution of exposure to process-generated substances at the workplace. Mol Oncol 2021; 15:753-763. [PMID: 33544948 PMCID: PMC7931128 DOI: 10.1002/1878-0261.12925] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 01/29/2021] [Accepted: 02/03/2021] [Indexed: 11/25/2022] Open
Abstract
Respirable crystalline silica in mineral dust, wood dust, diesel engine exhaust emissions and welding fumes are among the most common process-generated substances to which millions of workers are exposed daily. The composition of process-generated substances can vary substantially, depending on the parameters of the underlying processes; for example, the composition and intensity of diesel motor emissions differs among the various generations of diesel engines and working environments (e.g. surface or underground mining). We illustrate how common these occupational exposures are and discuss challenges in estimating their global prevalence and their contribution to the burden of occupational cancer. Estimates of the number and proportion of workers exposed in most countries and on a global scale are generally scarce. A remarkable exception is based on the proactive bottom-up estimates generated within the European Network for Silica. Actions to reduce exposures and research to fill gaps in knowledge adapted to local settings are warranted to mitigate the occupational cancer burden, especially in under-researched settings including low- and middle-income countries.
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Affiliation(s)
- Ann Olsson
- International Agency for Research in Cancer (IARC)World Health Organization (WHO)LyonFrance
| | - Hans Kromhout
- Institute for Risk Assessment SciencesUtrecht UniversityThe Netherlands
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Newton A, Adams K, Serdar B, Dickinson LM, Koehler K. Personal and area exposure assessment at a stainless steel fabrication facility: an evaluation of inhalable, time-resolved PM 10, and bioavailable airborne metals. J Occup Environ Hyg 2021; 18:90-100. [PMID: 33555996 DOI: 10.1080/15459624.2020.1854460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This study describes a comprehensive exposure assessment in a stainless steel welding facility, measuring personal inhalable PM and metals, time-resolved PM10 area metals, and the bioavailable fraction of area inhalable metals. Eighteen participants wore personal inhalable samplers for two, nonconsecutive shifts. Area inhalable samplers and a time-resolved PM10 X-ray fluorescence spectrometer were used in different work areas each sampling day. Inhalable and bioavailable metals were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Median exposures to chromium, nickel, and manganese across all measured shifts were 66 (range: 13-300) μg/m3, 29 (5.7-132) μg/m3, and 22 (1.5-119) μg/m3, respectively. Most exposure variation was seen between workers ( 0.79 < ICC < 0.55 ) , although cobalt and inhalable PM showed most variation within workers. Manganese was the most bioavailable metal from the inhalable size fraction (16 ± 3%), and chromium and nickel were 1.2 ± 0.08% and 2.6 ± 1.2% bioavailable, respectively. This comprehensive approach to welding-fume exposure assessment can allow for targeted approaches to controlling exposures based not only on individual measurements, but also on metal-specific measures and assessments of bioavailability.
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Affiliation(s)
- Ashley Newton
- Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Karin Adams
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA
- Idaho National Laboratory, Idaho Falls, Idaho, USA
| | - Berrin Serdar
- Environmental Health Associates LLC, Englewood, Colorado, USA
| | - L Miriam Dickinson
- Family Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Kirsten Koehler
- Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
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Abstract
Welding, a fabrication process that joins metals or thermoplastics by causing coalescence, is indispensable in modern society and ubiquitous in industry. Welding generates fumes that contain several metals and gases that comprise fine and ultrafine particles with the potential for adverse effects. Although health risks of welders have been evaluated in different populations, occupational exposure to welding fumes is still considered to be an important health problem, especially in developing countries. The aim of this study was to investigate the effects of welding fume exposure on important oxidative stress parameters such as superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), total glutathione (GSH), glutathione peroxidase (GPx), malondialdehyde (MDA), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in Turkish welders (n = 48). The influence of confounding factors such as age, smoking habits, alcohol consumption, and duration of exposure on the studied parameters was also analyzed. In our study, significant decreases in the levels of GSH and activities of CAT, SOD, and GPx and significant increases of MDA, 8-OHdG levels and GR activity were found in the workers compared to the controls. There was a negative correlation between GSH levels and alcohol usage. Also, older workers (≥35 years) had significantly higher GR levels than younger workers. But smoking and alcohol usage, duration of exposure, and utilization of protective measures had no significant effect on the studied parameters in the workers. These results indicate that occupational exposure to welding fumes appears to induce oxidative stress and oxidative DNA damage.
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Affiliation(s)
- Dilek Tokaç
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
| | - Hatice Gül Anlar
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Zonguldak Bülent Ecevit University, Zonguldak, Turkey
| | - Merve Bacanlı
- Department of Pharmaceutical Toxicology, Gülhane Faculty of Pharmacy, University of Health Sciences Turkey, Ankara, Turkey
| | - Sevtap Aydın Dilsiz
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
| | - Servet İritaş
- The Council of Forensic Medicine, Branch Office of Ankara, Ankara, Turkey
| | - Nurşen Başaran
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
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Riccelli MG, Goldoni M, Poli D, Mozzoni P, Cavallo D, Corradi M. Welding Fumes, a Risk Factor for Lung Diseases. Int J Environ Res Public Health 2020; 17:E2552. [PMID: 32276440 DOI: 10.3390/ijerph17072552] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 04/03/2020] [Accepted: 04/04/2020] [Indexed: 12/13/2022]
Abstract
(1) Background: Welding fumes (WFs) are composed of fine and ultrafine particles, which may reach the distal airways and represent a risk factor for respiratory diseases. (2) Methods: In vitro and in vivo studies to understand WFs pathogenesis were selected. Epidemiological studies, original articles, review, and meta-analysis to examine solely respiratory disease in welders were included. A systematic literature search, using PubMed, National Institute for Occupational Safety and Health Technical Information Center (NIOSHTIC), and Web of Science databases, was performed. (3) Results: Dose, time of exposure, and composition of WFs affect lung injury. Inflammation, lung defense suppression, oxidative stress, DNA damage, and genotoxic effects were observed after exposure both to mild and stainless steel WFs. (4) Conclusions: The detection of lung diseases associated with specific occupational exposure is crucial as complete avoidance or reduction of the exposure is difficult to achieve. Further studies in the area of particle research may aid the understanding of mechanisms involved in welding-related lung disease and to expand knowledge in welding-related cardiovascular diseases.
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Su TY, Pan CH, Hsu YT, Lai CH. Effects of Heavy Metal Exposure on Shipyard Welders: A Cautionary Note for 8-Hydroxy-2'-Deoxyguanosine. Int J Environ Res Public Health 2019; 16:E4813. [PMID: 31795521 DOI: 10.3390/ijerph16234813] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 11/22/2019] [Accepted: 11/26/2019] [Indexed: 12/17/2022]
Abstract
Oxidative stress plays a crucial role in the development of diseases induced by welding fumes. To our knowledge, little information is available on the relationship between multiple heavy metal exposure and oxidative stress in welders. We assessed the relationship between multiple heavy metal exposure and oxidative damage by analyzing 174 nonsmoking male welders in a shipyard. Urinary metals were used as the internal dose of exposure to metals in welding fumes, and urinary 8-hydroxy-2’-deoxyguanosine (8-OHdG) was used as an oxidative DNA damage marker. The relationship between workers’ metal levels and 8-OHdG was estimated using a multiple linear regression model. The geometric mean levels of urinary chromium (Cr), nickel (Ni), cadmium (Cd), and lead (Pb) were considerably higher in welders than in controls. Urinary Cr and Ni were determined as effective predictors of urinary 8-OHdG levels after adjusting for covariates. Oxidative DNA damage was associated with both Cr and Ni of welding fume exposure in shipyard welders (Ln Cr: β = 0.33, 95%C.I. = 0.16–0.49; Ln Ni: β = 0.27, 95%C.I. = 0.12–0.43). In this study, we investigated the significantly positive relationship between urinary metals (especially Cr and Ni) and 8-OHdG in nonsmoking shipyard welders. Moreover, the use of particulate respirators did not reduce metal exposure and oxidative damage. Therefore, we infer that hazard identification for welders should be conducted.
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Honaryar MK, Lunn RM, Luce D, Ahrens W, 't Mannetje A, Hansen J, Bouaoun L, Loomis D, Byrnes G, Vilahur N, Stayner L, Guha N. Welding fumes and lung cancer: a meta-analysis of case-control and cohort studies. Occup Environ Med 2019; 76:422-431. [PMID: 30948521 DOI: 10.1136/oemed-2018-105447] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 12/14/2018] [Accepted: 02/13/2019] [Indexed: 12/29/2022]
Abstract
BACKGROUND An estimated 110 million workers are exposed to welding fumes worldwide. Welding fumes are classified by the International Agency for Research on Cancer as carcinogenic to humans (group 1), based on sufficient evidence of lung cancer from epidemiological studies. OBJECTIVE To conduct a meta-analysis of case-control and cohort studies on welding or exposure to welding fumes and risk of lung cancer, accounting for confounding by exposure to asbestos and tobacco smoking. METHODS The literature was searched comprehensively in PubMed, reference lists of relevant publications and additional databases. Overlapping populations were removed. Meta-relative risks (mRRs) were calculated using random effects models. Publication bias was assessed using funnel plot, Eggers's test and Begg's test. RESULTS Forty-five studies met the inclusion criteria (20 case-control, 25 cohort/nested case-control), which reduced to 37 when overlapping study populations were removed. For 'ever' compared with 'never' being a welder or exposed to welding fumes, mRRs and 95% CIs were 1.29 (1.20 to 1.39; I2=26.4%; 22 studies) for cohort studies, 1.87 (1.53 to 2.29; I2=44.1%; 15 studies) for case-control studies and 1.17 (1.04 to 1.38; I2=41.2%) for 8 case-control studies that adjusted for smoking and asbestos exposure. The mRRs were 1.32 (95% CI 1.20 to 1.45; I2=6.3%; 15 studies) among 'shipyard welders', 1.44 (95% CI 1.07 to 1.95; I2=35.8%; 3 studies) for 'mild steel welders' and 1.38 (95% CI 0.89 to 2.13; I2=68.1%; 5 studies) among 'stainless steel welders'. Increased risks persisted regardless of time period, geographic location, study design, occupational setting, exposure assessment method and histological subtype. CONCLUSIONS These results support the conclusion that exposure to welding fumes increases the risk of lung cancer, regardless of the type of steel welded, the welding method (arc vs gas welding) and independent of exposure to asbestos or tobacco smoking.
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Affiliation(s)
- Manoj Kumar Honaryar
- International Agency for Research on Cancer, Lyon, France
- Service de médcine et addictologie, Centre Hospitalier des Quatre Villes (CH4V), Saint-Cloud et Sèvres, France
- Ecole des hautes études en santé publique (EHESP), Paris, France
| | - Ruth M Lunn
- National Institute of Environmental Health Sciences, Durham, North Carolina, USA
| | - Danièle Luce
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Pointe-à-Pitre, France
| | - Wolfgang Ahrens
- Leibniz Institute for Prevention Research and Epidemiology - BIPS, Bremen, Germany
| | - Andrea 't Mannetje
- Centre for Public Health Research, Massey University, Wellington, New Zealand
| | - Johnni Hansen
- Danish Cancer Society Research Center, København, Denmark
| | | | - Dana Loomis
- International Agency for Research on Cancer, Lyon, France
- University of Nevada, Reno, Reno, Nevada, USA
| | - Graham Byrnes
- International Agency for Research on Cancer, Lyon, France
| | - Nadia Vilahur
- International Agency for Research on Cancer, Lyon, France
- European Commission, Italy
| | - Leslie Stayner
- Division of Epidemiology and Biostatistics, University of Illinois, School of Public Health, Chicago, Illinois, USA
| | - Neela Guha
- International Agency for Research on Cancer, Lyon, France
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, California, USA
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12
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Leso V, Vetrani I, Della Volpe I, Nocera C, Iavicoli I. Welding Fume Exposure and Epigenetic Alterations: A Systematic Review. Int J Environ Res Public Health 2019; 16:ijerph16101745. [PMID: 31108839 PMCID: PMC6571852 DOI: 10.3390/ijerph16101745] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 05/11/2019] [Accepted: 05/13/2019] [Indexed: 11/16/2022]
Abstract
Epigenetics are heritable changes in gene expression not coded in the DNA sequence, which stand at the interface between the genome, environmental exposure and development. From an occupational health perspective, epigenetic variants may link workplace exposures and health effects. Therefore, this review aimed to overview possible epigenetic effects induced by welding fumes on exposed workers and health implications. A systematic search was performed on Pubmed, Scopus, and ISI Web of Knowledge databases. DNA methylation changes have been reported in genes responsible for the cardiac autonomic function and coagulation, i.e., LINE-1, GPR133 and F2RL3, in mitochondrial-DNA-sequences involved in the regulation of energy-generation/redox-signaling, as well as in inflammatory activated genes, i.e., iNOS. However, the limited number of retrieved articles, their cross-sectional nature, the lack of a suitable qualitative-quantitative exposure assessment, and the heterogeneity of biological-outcomes investigated, prevent the extrapolation of a definite causal relationship between welding fumes and epigenetic phenomena. Future studies should clarify the function of such epigenetic alterations as possible markers of occupational exposure and early effect, dose-response relationships, and underlying molecular mechanisms. Overall, this may be helpful to guide suitable risk assessment and management strategies to protect the health of workers exposed to welding fumes.
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Affiliation(s)
- Veruscka Leso
- Section of Occupational Medicine, Department of Public Health, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
| | - Ilaria Vetrani
- Section of Occupational Medicine, Department of Public Health, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
| | - Ilaria Della Volpe
- Section of Occupational Medicine, Department of Public Health, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
| | - Caterina Nocera
- Section of Occupational Medicine, Department of Public Health, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
| | - Ivo Iavicoli
- Section of Occupational Medicine, Department of Public Health, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
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Gobba NAEK, Hussein Ali A, El Sharawy DE, Hussein MA. The potential hazardous effect of exposure to iron dust in Egyptian smoking and nonsmoking welders. Arch Environ Occup Health 2018; 73:189-202. [PMID: 28375782 DOI: 10.1080/19338244.2017.1314930] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 03/28/2017] [Indexed: 06/07/2023]
Abstract
Exposure to iron dust and welding fumes is widespread and may increase the risk of lung inflammation. The aim of this study was to identify associations between exposure to iron/welding fumes and the levels of inflammatory parameters and allergic mediators among 120 Egyptian men. Forty nonsmoking and 40 smoking Egyptian welders as well as 40 healthy volunteers who were never exposed to welding fumes and were nonsmoking were enrolled in the study. Peak expiratory flow rates (PEFR) assessed at the end of the shift of work on working days revealed an impairment in lung function, with the smoking workers showing the worse results, followed by nonsmoking workers, as compared to healthy volunteers. Moreover, the results of the present study showed a significant increase in serum iron and immunoglobulin E, as well as plasma thiobarbaturic acid reactive substances, C-reactive protein, tumor necrosis factor-alpha, haptoglobin, interleukin-2, interleukin-6 and interleukin-23 histamine, lactate dehydrogenase isoenzyme-3, and calcitonin. In addition, the results revealed significant decrease in plasma α-1-antitrypsin and serum transferrin, as well as blood activities of antioxidant enzymes: catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase (as compared with control group). However, there was a nonsignificant change in arginase and α-L-fucosidase in smoking and nonsmoking welders exposed to iron dust and welding fumes. In conclusion, occupational exposure to iron dust and welding fumes increases lung inflammation risk among Egyptian blacksmith workers, a condition that worsens with smoking.
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Affiliation(s)
- Naglaa Abd El Khalik Gobba
- a Department of Pharmacology and Toxicology, College of Pharmacy , Misr University for Science and Technology (MUST) , 6th of October City , Egypt
| | - Abdelmaksoud Hussein Ali
- b Department of Biochemistry, Faculty of Veterinary Medicine , Benha University , Qalioubeya , Egypt
| | - Dalia E El Sharawy
- c Department of Chest Diseases, Faculty of Medicine , Tanta University , Cairo , Egypt
| | - Mohammed Abdalla Hussein
- d Department of Biochemistry, Faculty of Applied Medical Sciences , October 6 University , 6th of October City , Egypt
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14
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Abstract
Welding fume exposure can increase the risk of chronic obstructive pulmonary disease (COPD). The aim of this study was to evaluate the optimal grouping schemes of welding fume exposure in shipyard welders for future accurate examination of the association between welding fume exposure and COPD. Industrial hygiene records, including welding fume measurements between 2002 and 2009 were collected from a shipyard. A total of 2,360 personal welding fume measurements was compiled with a geometric mean of 1.66 mg/m3 and a geometric standard deviation of 4.02. Welding jobs were categorized into 8 groups. There were 9 working areas. To obtain the optimal grouping scheme, various grouping schemes were created using job, area, and job*area combination. To compare various grouping schemes, contrast and precision were calculated for each grouping scheme. For all measurement data, group mean ranking method created by ranking geometric means of the job*area combination into 3 groups (group mean ranking method) showed the best contrast and precision values among various grouping schemes, followed by grouping based on the job. For a subset of the data excluding job*area combinations with less than 10 measurements, grouping based on the job showed greater contrast than group mean ranking method, while for other subsets, including only repeated measurement data or further excluding job*area combinations with less than 10 measurements from the repeated measurement subset, group mean ranking method showed greater contrast than grouping based on the job. Our results showed that group mean ranking or grouping based on the job could be a candidate for the optimal grouping schemes in this shipyard. Our efforts for optimal grouping scheme may aid future cohort study to elucidate the association between welding fume exposure and COPD.
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Affiliation(s)
- Dong-Hee Koh
- a Department of Occupational Environmental Medicine , International St. Mary's Hospital, Catholic Kwandong University , Incheon , Korea
| | - Sun-Woo Lee
- b Gaon Institute of Occupational Environment Research , Busan , Korea
| | - Byeong-Jin Ye
- c Gimhae Clinic, Occupational Health Center , Inje University , Busan , Korea
| | - Jung-Il Kim
- d Department of Occupational and Environmental Medicine , Dong-A University Hospital , Busan , Korea
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15
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Mino J, Quémerais B. Using a Particle Counter to Inform the Creation of Similar Exposure Groups and Sampling Protocols in a Structural Steel Fabrication Facility. Toxics 2017; 5:toxics5040034. [PMID: 29168761 PMCID: PMC5750562 DOI: 10.3390/toxics5040034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 11/14/2017] [Accepted: 11/17/2017] [Indexed: 11/16/2022]
Abstract
The objective of this project was to create similar exposure groups (SEGs) for occupational monitoring in a structural steel fabrication facility. Qualitative SEG formation involved worksite observation, interviews, and audits of materials and procedures. These were supplemented with preliminary task-based shop survey data collected using a condensation particle counter. A total of six SEGs were formed, with recommendations for occupational exposure sampling for five groups, as well as ambient sampling recommendations to address areas on the operational floor found to have higher particle concentrations. The combination of direct reading device data and qualitative SEG formation techniques is a valuable approach, as it contains both the monetary and temporal costs of worksite exposure monitoring. This approach also provides an empowering in-house analysis of potentially problematic areas, and results in the streamlining of occupational exposure assessment.
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Affiliation(s)
- James Mino
- Division of Preventive Medicine, University of Alberta, Edmonton, AB T6G 2S2, Canada.
| | - Bernadette Quémerais
- Division of Preventive Medicine, University of Alberta, Edmonton, AB T6G 2S2, Canada.
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16
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Abstract
OBJECTIVES To document if manganese from welding causes health effects including neurological symptoms associated with manganese exposure. MATERIAL AND METHODS An anonymous questionnaire survey for a total of 505 welders at 3 welding facilities in Qingdao City, China was administered and analyzed. RESULTS Numerous symptoms were reported by the welders including difficulty with eyes for 43% of them, sore throat for 30% of them, and tremors were reported by over 18% of them. Tremors were associated with longer periods of work as a welder and correlated with the relative cleanliness at the 3 different facilities. Tremors did not correlate with smoking. CONCLUSIONS Manganese-exposed welders reported a variety of symptoms related to work and showed neurological disturbances that correlated with amount of exposure. Int J Occup Med Environ Health 2017;30(2):241-247.
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Affiliation(s)
- Huaqiang Zhang
- Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China (Department of Occupational Health).
| | - Chunsheng Xu
- Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China (Department of Occupational Health)
| | - Honglin Wang
- Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China (Department of Occupational Health)
| | - Arthur L Frank
- Drexel University School of Public Health, Philadelphia, USA (Department of Environmental and Occupational Health).
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17
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Keane M, Siert A, Stone S, Chen BT. Profiling stainless steel welding processes to reduce fume emissions, hexavalent chromium emissions and operating costs in the workplace. J Occup Environ Hyg 2016; 13:1-8. [PMID: 26267301 PMCID: PMC4764053 DOI: 10.1080/15459624.2015.1072634] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Nine gas metal arc welding (GMAW) processes for stainless steel were assessed for fume generation rates, fume generation rates per g of electrode consumed, and emission rates for hexavalent chromium (Cr(6+)). Elemental manganese, nickel, chromium, iron emissions per unit length of weld, and labor plus consumables costs were similarly measured. Flux-cored arc welding and shielded metal arc (SMAW) processes were also studied. The objective was to identify the best welding processes for reducing workplace exposures, and estimate costs for all processes. Using a conical chamber, fumes were collected, weighed, recovered, and analyzed by inductively coupled atomic emission spectroscopy for metals, and by ion chromatography for Cr(6+). GMAW processes used were Surface Tension Transfer, Regulated Metal Deposition, Cold Metal Transfer, short-circuit, axial spray, and pulsed spray modes. Flux-cored welding used gas shielding; SMAW used E308 rods. Costs were estimated as dollars per m length of a ¼ in (6.3 mm) thick horizontal butt weld; equipment costs were estimated as ratios of new equipment costs to a 250 ampere capacity SMAW welding machine. Results indicate a broad range of fume emission factors for the processes studied. Fume emission rates per g of electrode were lowest for GMAW processes such as pulsed-spray mode (0.2 mg/g), and highest for SMAW (8 mg fume/g electrode). Emission rates of Cr(6+) ranged from 50-7800 µg/min, and Cr(6+) generation rates per g electrode ranged from 1-270 µg/g. Elemental Cr generation rates spanned 13-330 µg/g. Manganese emission rates ranged from 50-300 µg/g. Nickel emission rates ranged from 4-140 µg/g. Labor and consumables costs ranged from $3.15 (GMAW pulsed spray) to $7.40 (SMAW) per meter of finished weld, and were measured or estimated for all 11 processes tested. Equipment costs for some processes may be as much as five times the cost of a typical SMAW welding machine. The results show that all of the GMAW processes in this study can substantially reduce fume, Cr(6+), manganese and costs relative to SMAW, the most commonly used welding process, and several have exceptional capabilities for reducing emissions.
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Affiliation(s)
- Michael Keane
- National Institute for Occupational Safety and Health, Health Effects Laboratory Division, 1095 Willowdale Rd. Morgantown, WV 26505
| | | | - Samuel Stone
- National Institute for Occupational Safety and Health, Health Effects Laboratory Division, 1095 Willowdale Rd. Morgantown, WV 26505
| | - Bean T. Chen
- National Institute for Occupational Safety and Health, Health Effects Laboratory Division, 1095 Willowdale Rd. Morgantown, WV 26505
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18
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Graczyk H, Lewinski N, Zhao J, Concha-Lozano N, Riediker M. Characterization of Tungsten Inert Gas (TIG) Welding Fume Generated by Apprentice Welders. Ann Occup Hyg 2015; 60:205-19. [PMID: 26464505 PMCID: PMC4738234 DOI: 10.1093/annhyg/mev074] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 09/14/2015] [Indexed: 12/30/2022]
Abstract
Tungsten inert gas welding (TIG) represents one of the most widely used metal joining processes in industry. Its propensity to generate a greater portion of welding fume particles at the nanoscale poses a potential occupational health hazard for workers. However, current literature lacks comprehensive characterization of TIG welding fume particles. Even less is known about welding fumes generated by welding apprentices with little experience in welding. We characterized TIG welding fume generated by apprentice welders (N = 20) in a ventilated exposure cabin. Exposure assessment was conducted for each apprentice welder at the breathing zone (BZ) inside of the welding helmet and at a near-field (NF) location, 60cm away from the welding task. We characterized particulate matter (PM4), particle number concentration and particle size, particle morphology, chemical composition, reactive oxygen species (ROS) production potential, and gaseous components. The mean particle number concentration at the BZ was 1.69E+06 particles cm−3, with a mean geometric mean diameter of 45nm. On average across all subjects, 92% of the particle counts at the BZ were below 100nm. We observed elevated concentrations of tungsten, which was most likely due to electrode consumption. Mean ROS production potential of TIG welding fumes at the BZ exceeded average concentrations previously found in traffic-polluted air. Furthermore, ROS production potential was significantly higher for apprentices that burned their metal during their welding task. We recommend that future exposure assessments take into consideration welding performance as a potential exposure modifier for apprentice welders or welders with minimal training.
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Affiliation(s)
- Halshka Graczyk
- 1.Institute for Work and Health, University of Lausanne and Geneva, 1066 Epalinges-Lausanne, Switzerland
| | - Nastassja Lewinski
- 1.Institute for Work and Health, University of Lausanne and Geneva, 1066 Epalinges-Lausanne, Switzerland; 2.Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Jiayuan Zhao
- 1.Institute for Work and Health, University of Lausanne and Geneva, 1066 Epalinges-Lausanne, Switzerland
| | - Nicolas Concha-Lozano
- 1.Institute for Work and Health, University of Lausanne and Geneva, 1066 Epalinges-Lausanne, Switzerland
| | - Michael Riediker
- 1.Institute for Work and Health, University of Lausanne and Geneva, 1066 Epalinges-Lausanne, Switzerland; 3.SAFENANO, IOM Singapore, Singapore 048622
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19
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Li H, Hedmer M, Wojdacz T, Hossain MB, Lindh CH, Tinnerberg H, Albin M, Broberg K. Oxidative stress, telomere shortening, and DNA methylation in relation to low-to-moderate occupational exposure to welding fumes. Environ Mol Mutagen 2015; 56:684-93. [PMID: 26013103 PMCID: PMC4755249 DOI: 10.1002/em.21958] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 05/01/2015] [Indexed: 05/27/2023]
Abstract
Evidence suggests that exposure to welding fumes is a risk factor for lung cancer. We examined relationships between low-to-moderate occupational exposure to particles from welding fumes and cancer-related biomarkers for oxidative stress, changes in telomere length, and alterations in DNA methylation. We enrolled 101 welders and 127 controls (all currently nonsmoking men) from southern Sweden. We performed personal sampling of respirable dust and measured 8-oxodG concentrations in urine using a simplified liquid chromatography tandem mass spectrometry method. Telomere length in peripheral blood was measured by quantitative polymerase chain reaction. Methylation status of 10 tumor suppressor genes was determined by methylation-sensitive high-resolution melting analysis. All analyses were adjusted for age, body mass index, previous smoking, passive smoking, current residence, and wood burning stove/boiler at home. Welders were exposed to respirable dust at 1.2 mg/m(3) (standard deviation, 3.3 mg/m(3); range, 0.1-19.3), whereas control exposures did not exceed 0.1 mg/m(3) (P < 0.001). Welders and controls did not differ in 8-oxodG levels (β = 1.2, P = 0.17) or relative telomere length (β = -0.053, P = 0.083) in adjusted models. Welders showed higher probability of adenomatous polyposis coli (APC) methylation in the unadjusted model (odds ratio = 14, P = 0.014), but this was not significant in the fully adjusted model (P = 0.052). Every working year as a welder was associated with 0.0066 units shorter telomeres (95% confidence interval -0.013 to -0.00053, P = 0.033). Although there were no clear associations between concentrations of respirable dust and the biomarkers, there were modest signs of associations between oxidative stress, telomere alterations, DNA methylation, and occupational exposure to low-to-moderate levels of particles.
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Affiliation(s)
- Huiqi Li
- Department of Laboratory Medicine, Section of Occupational and Environmental MedicineLund UniversityLundSweden
| | - Maria Hedmer
- Department of Laboratory Medicine, Section of Occupational and Environmental MedicineLund UniversityLundSweden
| | - Tomasz Wojdacz
- Institute of Environmental Medicine, Karolinska InstitutetStockholmSweden
| | - Mohammad Bakhtiar Hossain
- Department of Laboratory Medicine, Section of Occupational and Environmental MedicineLund UniversityLundSweden
| | - Christian H. Lindh
- Department of Laboratory Medicine, Section of Occupational and Environmental MedicineLund UniversityLundSweden
| | - Håkan Tinnerberg
- Department of Laboratory Medicine, Section of Occupational and Environmental MedicineLund UniversityLundSweden
| | - Maria Albin
- Department of Laboratory Medicine, Section of Occupational and Environmental MedicineLund UniversityLundSweden
| | - Karin Broberg
- Department of Laboratory Medicine, Section of Occupational and Environmental MedicineLund UniversityLundSweden
- Institute of Environmental Medicine, Karolinska InstitutetStockholmSweden
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20
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Suri R, Periselneris J, Lanone S, Zeidler-Erdely PC, Melton G, Palmer KT, Andujar P, Antonini JM, Cohignac V, Erdely A, Jose RJ, Mudway I, Brown J, Grigg J. Exposure to welding fumes and lower airway infection with Streptococcus pneumoniae. J Allergy Clin Immunol 2015; 137:527-534.e7. [PMID: 26277596 DOI: 10.1016/j.jaci.2015.06.033] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 05/29/2015] [Accepted: 06/29/2015] [Indexed: 12/18/2022]
Abstract
BACKGROUND Welders are at increased risk of pneumococcal pneumonia. The mechanism for this association is not known. The capacity of pneumococci to adhere to and infect lower airway cells is mediated by host-expressed platelet-activating factor receptor (PAFR). OBJECTIVE We sought to assess the effect of mild steel welding fumes (MS-WF) on PAFR-dependent pneumococcal adhesion and infection to human airway cells in vitro and on pneumococcal airway infection in a mouse model. METHODS The oxidative potential of MS-WF was assessed by their capacity to reduce antioxidants in vitro. Pneumococcal adhesion and infection of A549, BEAS-2B, and primary human bronchial airway cells were assessed by means of quantitative bacterial culture and expressed as colony-forming units (CFU). After intranasal instillation of MS-WF, mice were infected with Streptococcus pneumoniae, and bronchoalveolar lavage fluid (BALF) and lung CFU values were determined. PAFR protein levels were assessed by using immunofluorescence and immunohistochemistry, and PAFR mRNA expression was assessed by using quantitative PCR. PAFR was blocked by CV-3988, and oxidative stress was attenuated by N-acetylcysteine. RESULTS MS-WF exhibited high oxidative potential. In A549 and BEAS-2B cells MS-WF increased pneumococcal adhesion and infection and PAFR protein expression. Both CV-3988 and N-acetylcysteine reduced MS-WF-stimulated pneumococcal adhesion and infection of airway cells. MS-WF increased mouse lung PAFR mRNA expression and increased BALF and lung pneumococcal CFU values. In MS-WF-exposed mice CV-3988 reduced BALF CFU values. CONCLUSIONS Hypersusceptibility of welders to pneumococcal pneumonia is in part mediated by the capacity of welding fumes to increase PAFR-dependent pneumococcal adhesion and infection of lower airway cells.
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Affiliation(s)
- Reetika Suri
- Blizard Institute, Queen Mary University of London, London, United Kingdom
| | - Jimstan Periselneris
- Centre for Inflammation and Tissue Repair, Department of Medicine, Royal Free and University College Medical School, Rayne Institute, London, United Kingdom
| | - Sophie Lanone
- Inserm U955 Équipe 4, Faculté de Médecine, Créteil, France
| | - Patti C Zeidler-Erdely
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV
| | | | - Keith T Palmer
- MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, United Kingdom
| | - Pascal Andujar
- Inserm U955 Équipe 4, Faculté de Médecine, Créteil, France
| | - James M Antonini
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV
| | | | - Aaron Erdely
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV
| | - Ricardo J Jose
- Centre for Inflammation and Tissue Repair, Department of Medicine, Royal Free and University College Medical School, Rayne Institute, London, United Kingdom
| | - Ian Mudway
- MRC-PHE Centre for Environment and Health, Analytical & Environmental Sciences Division, Faculty of Life Sciences & Medicine, King's College London, London, United Kingdom
| | - Jeremy Brown
- Centre for Inflammation and Tissue Repair, Department of Medicine, Royal Free and University College Medical School, Rayne Institute, London, United Kingdom
| | - Jonathan Grigg
- Blizard Institute, Queen Mary University of London, London, United Kingdom.
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21
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Abstract
Welding is used extensively in different industries. Welders are always at a risk of exposure to a number of gases and metal-containing fumes in their respective microenvironments in which they work. Welding fumes consist of a wide range of complex metal oxide particles which can deposit in different parts of their bodies causing serious health problems. In the present study, 35 welders (age: 33.80 ± 1.04 years) from two iron-based industries have been assessed for DNA damage in peripheral blood lymphocytes using single-cell gel electrophoresis. An equal number of subjects (N = 35; age: 30.40 ± 1.51 years) matched to exposed subjects with respect to sex, age, socioeconomic status, smoking, and alcoholic habits were taken as controls. The results revealed that the damaged cell frequency (DCF) and mean comet tail length (CTL) in welders were significantly higher as compared to the controls (DCF: 69.74 ± 1.68 vs. 31.14 ± 1.67 and CTL: 29.21 ± 1.48 vs. 1.47 ± 0.08; p < 0.05). The effect of confounding factors such as age, duration of exposure, smoking, and drinking habits was also studied. Blood lead levels also showed a positive correlation with duration of exposure and CTL, and the overall results indicated an increased genetic damage as an index of genotoxicity in workers occupationally engaged in welding microenvironments.
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Affiliation(s)
- Zorawar Singh
- Department of Zoology, Khalsa College, Amritsar, Punjab, India
| | - Pooja Chadha
- Department of Zoology, Guru Nanak Dev University, Amritsar, Punjab, India
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22
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Cena LG, Chisholm WP, Keane MJ, Chen BT. A Field Study on the Respiratory Deposition of the Nano-Sized Fraction of Mild and Stainless Steel Welding Fume Metals. J Occup Environ Hyg 2015; 12:721-728. [PMID: 25985454 PMCID: PMC4708286 DOI: 10.1080/15459624.2015.1043055] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A field study was conducted to estimate the amount of Cr, Mn, and Ni deposited in the respiratory system of 44 welders in two facilities. Each worker wore a nanoparticle respiratory deposition (NRD) sampler during gas metal arc welding (GMAW) of mild and stainless steel and flux-cored arc welding (FCAW) of mild steel. Several welders also wore side-by-side NRD samplers and closed-face filter cassettes for total particulate samples. The NRD sampler estimates the aerosol's nano-fraction deposited in the respiratory system. Mn concentrations for both welding processes ranged 2.8-199 μg/m3; Ni concentrations ranged 10-51 μg/m3; and Cr concentrations ranged 40-105 μg/m3. Cr(VI) concentrations ranged between 0.5-1.3 μg/m3. For the FCAW process the largest concentrations were reported for welders working in pairs. As a consequence this often resulted in workers being exposed to their own welding fumes and to those generated from the welding partner. Overall no correlation was found between air velocity and exposure (R2 = 0.002). The estimated percentage of the nano-fraction of Mn deposited in a mild-steel-welder's respiratory system ranged between 10 and 56%. For stainless steel welding, the NRD samplers collected 59% of the total Mn, 90% of the total Cr, and 64% of the total Ni. These results indicate that most of the Cr and more than half of the Ni and Mn in the fumes were in the fraction smaller than 300 nm.
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Affiliation(s)
- L G Cena
- a Health Effects Laboratory Division, National Institute for Occupational Safety and Health , Morgantown , West Virginia
| | - W P Chisholm
- a Health Effects Laboratory Division, National Institute for Occupational Safety and Health , Morgantown , West Virginia
| | - M J Keane
- a Health Effects Laboratory Division, National Institute for Occupational Safety and Health , Morgantown , West Virginia
| | - B T Chen
- a Health Effects Laboratory Division, National Institute for Occupational Safety and Health , Morgantown , West Virginia
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Bertram J, Brand P, Schettgen T, Lenz K, Purrio E, Reisgen U, Kraus T. Human biomonitoring of chromium and nickel from an experimental exposure to manual metal arc welding fumes of low and high alloyed steel. ACTA ACUST UNITED AC 2014; 59:467-80. [PMID: 25512666 DOI: 10.1093/annhyg/meu104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 10/29/2014] [Indexed: 11/13/2022]
Abstract
OBJECTIVES The uptake and elimination of metals from welding fumes is currently not fully understood. In the Aachen Workplace Simulation Laboratory (AWSL) it is possible to investigate the impact of welding fumes on human subjects under controlled exposure conditions. In this study, the uptake and elimination of chromium or chromium (VI) respectively as well as nickel was studied in subjects after exposure to the emissions of a manual metal arc welding process using low or high alloyed steel. METHODS In this present study 12 healthy male non-smokers, who never worked as welders before, were exposed for 6h to welding fumes of a manual metal arc welding process. In a three-fold crossover study design, subjects were exposed in randomized order to either clean air, emissions from welding low alloyed steel, and emissions from welding high alloyed steel. Particle mass concentration of the exposure aerosol was 2.5mg m(-3). The content of chromium and nickel in the air was determined by analysing air filter samples on a high emission scenario. Urine analysis for chromium and nickel was performed before and after exposure using methods of human biomonitoring. RESULTS There were significantly elevated chromium levels after exposure to welding fumes from high alloyed steel compared to urinary chromium levels before exposure to high alloyed welding fumes, as well as compared to the other exposure scenarios. The mean values increased from 0.27 µg l(-1) to 18.62 µg l(-1). The results were in good agreement with already existing correlations between external and internal exposure (German exposure equivalent for carcinogenic working materials EKA). The variability of urinary chromium levels was high. For urinary nickel no significant changes could be detected at all. CONCLUSIONS Six-hour exposure to 2.5mg m(-3) high alloyed manual metal arc welding fumes lead to elevated urinary chromium levels far higher (7.11-34.16 µg l(-1)) than the German biological exposure reference value (BAR) of 0.6 µg l(-1) directly after exposure. On the other hand mean urinary nickel concentrations slightly increased, but did not exceed background levels due to lower bioavailability. We could underline with our single exposure experiment that a welding work related chromium exposure can be measured immediately after the work shift, while the same is not possible for nickel exposure due to lower nickel bioavailability. The data provide useful information for real occupational welding work places.
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Affiliation(s)
- Jens Bertram
- 1.Institute for Occupational Medicine and Social Medicine, RWTH Aachen University, Pauwelsstr. 30 D-52074, Aachen, Germany
| | - Peter Brand
- 1.Institute for Occupational Medicine and Social Medicine, RWTH Aachen University, Pauwelsstr. 30 D-52074, Aachen, Germany
| | - Thomas Schettgen
- 1.Institute for Occupational Medicine and Social Medicine, RWTH Aachen University, Pauwelsstr. 30 D-52074, Aachen, Germany
| | - Klaus Lenz
- 2.ISF-Welding and Joining Institute, Aachen University of Technology, Pontstr. 49 D-52062, Aachen, Germany
| | - Ellwyn Purrio
- 2.ISF-Welding and Joining Institute, Aachen University of Technology, Pontstr. 49 D-52062, Aachen, Germany
| | - Uwe Reisgen
- 2.ISF-Welding and Joining Institute, Aachen University of Technology, Pontstr. 49 D-52062, Aachen, Germany
| | - Thomas Kraus
- 1.Institute for Occupational Medicine and Social Medicine, RWTH Aachen University, Pauwelsstr. 30 D-52074, Aachen, Germany
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Abstract
To provide quantitative information to choose the best welding processes for minimizing workplace emissions, nine gas metal arc welding (GMAW) processes for mild steel were assessed for fume generation rates, normalized fume generation rates (milligram fume per gram of electrode consumed), and normalized generation rates for elemental manganese, nickel, and iron. Shielded metal arc welding (SMAW) and flux-cored arc-welding (FCAW) processes were also profiled. The fumes were collected quantitatively in an American Welding Society-type fume chamber and weighed, recovered, homogenized, and analyzed by inductively coupled atomic emission spectroscopy for total metals. The processes included GMAW with short circuit, globular transfer, axial spray, pulsed spray, Surface Tension Transfer™, Regulated Metal Deposition™, and Cold Metal Transfer™ (CMT) modes. Flux-cored welding was gas shielded, and SMAW was a single rod type. Results indicate a wide range of fume emission factors for the process variations studied. Fume emission rates per gram of electrode consumed were highest for SMAW (~13 mg fume g(-1) electrode) and lowest for GMAW processes such as pulsed spray (~1.5mg g(-1)) and CMT (~1mg g(-1)). Manganese emission rates per gram of electrode consumed ranged from 0.45 mg g(-1) (SMAW) to 0.08 mg g(-1) (CMT). Nickel emission rates were generally low and ranged from ~0.09 (GMAW short circuit) to 0.004 mg g(-1) (CMT). Iron emission rates ranged from 3.7 (spray-mode GMAW) to 0.49 mg g(-1) (CMT). The processes studied have significantly different costs, and cost factors are presented based on a case study to allow comparisons between processes in specific cost categories. Costs per linear meter of weld were $31.07 (SMAW), $12.37 (GMAW short circuit), and $10.89 (FCAW). Although no single process is the best for minimizing fume emissions and costs while satisfying the weld requirements, there are several processes that can minimize emissions. This study provides information to aid in those choices. Suggestions for overcoming barriers to utilizing new and less hazardous welding processes are also discussed.
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Affiliation(s)
- Michael J Keane
- 1. Health Effects Laboratory Division, National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV 26505, USA
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RYU JY, LEE SY, KIM DH. Obstructive pulmonary function impairment among Korean male workers exposed to organic solvents, iron oxide dust, and welding fumes. Ind Health 2013; 51:596-602. [PMID: 24131874 PMCID: PMC4202746 DOI: 10.2486/indhealth.2012-0213] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 09/24/2013] [Indexed: 05/26/2023]
Abstract
We evaluated spirometric obstructive pulmonary function impairment among workers who were occupationally exposed to organic solvents, iron oxide dust, or welding fumes. Data were collected from records of periodic health examinations of workers. In total, 448 Korean male workers were enrolled and classified into three exposure groups: exposure to organic solvents, iron oxide dust, or welding fumes. Logistic regression analysis was performed to evaluate the association between occupational exposure and pulmonary function. Compared to exposure to organic solvents, exposure to iron oxide dust was significantly associated with obstructive pulmonary function impairment (odds ratio [OR], 9.61; 95% confidence interval [CI], 2.20-41.97). The group exposed to welding fumes did not show a significantly higher OR compare to those exposed to organic solvents (OR, 2.83; 95% CI, 0.74-10.8). These results suggest that exposure to iron oxide dust has a greater association with obstructive pulmonary function impairment than exposure to organic solvents or welding fumes.
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Affiliation(s)
- Ji Young RYU
- Department of Occupational and Environmental Medicine, Inje
University Haeundae Paik Hospital, Republic of Korea
| | - Sang-Yoon LEE
- Department of Occupational and Environmental Medicine, Inje
University Haeundae Paik Hospital, Republic of Korea
| | - Dae Hwan KIM
- Department of Occupational and Environmental Medicine, Inje
University Haeundae Paik Hospital, Republic of Korea
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Vallières E, Pintos J, Lavoué J, Parent MÉ, Rachet B, Siemiatycki J. Exposure to welding fumes increases lung cancer risk among light smokers but not among heavy smokers: evidence from two case-control studies in Montreal. Cancer Med 2012; 1:47-58. [PMID: 23342253 PMCID: PMC3544431 DOI: 10.1002/cam4.6] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 05/01/2012] [Accepted: 05/02/2012] [Indexed: 11/09/2022] Open
Abstract
We investigated relationships between occupational exposure to gas and arc welding fumes and the risk of lung cancer among workers exposed to these agents throughout the spectrum of industries. Two population-based case-control studies were conducted in Montreal. Study I (1979-1986) included 857 cases and 1066 controls, and Study II (1996-2001) comprised 736 cases and 894 controls. Detailed job histories were obtained by interview and evaluated by an expert team of chemist-hygienists to estimate degree of exposure to approximately 300 substances for each job. Gas and arc welding fumes were among the agents evaluated. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) of lung cancer using logistic regression, adjusting for smoking history and other covariates. The two studies provided similar results, so a pooled analysis was conducted. Among all subjects, no significant association was found between lung cancer and gas welding fumes (OR = 1.1; 95% CI = 0.9-1.4) or arc welding fumes (OR = 1.0; 95% CI = 0.8-1.2). However, when restricting attention to light smokers, there was an increased risk of lung cancer in relation to gas welding fumes (OR = 2.9; 95% CI = 1.7-4.8) and arc welding fumes (OR = 2.3; 95% CI = 1.3-3.8), with even higher OR estimates among workers with the highest cumulative exposures. In conclusion, there was no detectable excess risk of lung cancer due to welding fumes among moderate to heavy smokers; but among light smokers we found an excess risk related to both types of welding fumes.
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Affiliation(s)
- Eric Vallières
- CHUM Research Center, University of Montreal, MontrealQuebec, Canada
| | - Javier Pintos
- CHUM Research Center, University of Montreal, MontrealQuebec, Canada
| | - Jérôme Lavoué
- CHUM Research Center, University of Montreal, MontrealQuebec, Canada
| | - Marie-Élise Parent
- INRS – Armand-Frappier Institute, University of QuebecLaval, Quebec, Canada
| | - Bernard Rachet
- London School of Hygiene and Tropical MedicineLondon, UK
| | - Jack Siemiatycki
- CHUM Research Center, University of Montreal, MontrealQuebec, Canada
- Department of Social and Preventive Medicine, University of MontrealMontreal, Quebec, Canada
- Guzzo-Cancer Research Society Chair in Environment and Cancer, School of Public Health, University of Montreal, MontrealQuebec, Canada
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Laohaudomchok W, Cavallari JM, Fang SC, Lin X, Herrick RF, Christiani DC, Weisskopf MG. Assessment of occupational exposure to manganese and other metals in welding fumes by portable X-ray fluorescence spectrometer. J Occup Environ Hyg 2010; 7:456-65. [PMID: 20526948 PMCID: PMC3072790 DOI: 10.1080/15459624.2010.485262] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Elemental analysis of welding fume samples can be done using several laboratory-based techniques. However, portable measurement techniques could offer several advantages. In this study, we sought to determine whether the portable X-ray fluorescence spectrometer (XRF) is suitable for analysis of five metals (manganese, iron, zinc, copper, and chromium) on 37-mm polytetrafluoroethylene filters. Using this filter fitted on a cyclone in line with a personal pump, gravimetric samples were collected from a group of boilermakers exposed to welding fumes. We assessed the assumption of uniform deposition of these metals on the filters, and the relationships between measurement results of each metal obtained from traditional laboratory-based XRF and the portable XRF. For all five metals of interest, repeated measurements with the portable XRF at the same filter area showed good consistency (reliability ratios are equal or close to 1.0 for almost all metals). The portable XRF readings taken from three different areas of each filter were not significantly different (p-values = 0.77 to 0.98). This suggested that the metal rich PM(2.5) deposits uniformly on the samples collected using this gravimetric method. For comparison of the two XRFs, the results from the portable XRF were well correlated and highly predictive of those from the laboratory XRF. The Spearman correlation coefficients were from 0.325 for chromium, to 0.995 for manganese and 0.998 for iron. The mean differences as a percent of the mean laboratory XRF readings were also small (<5%) for manganese, iron, and copper. The differences were greater for zinc and chromium, which were present at very low amounts in our samples and below the limits of detection of the portable XRF for many of the samples. These five metals were moderately to strongly correlated with the total fine particle fraction on filters (Spearman rho = 0.41 for zinc to 0.97 for iron). Such strong correlations and comparable results suggested that the portable XRF could be used as an effective and reliable tool for exposure assessment in many studies.
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Affiliation(s)
- Wisanti Laohaudomchok
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts 02215, USA.
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