1、i. T Key Words - Welding cancer, disease, exposure, fumes, gases, health, literature review, noise, radiation, toxicology Effects of Welding on Health - V Research performed by SRI International, Menlo Park, California, under contract with the American Welding Society and supported by industry contr
2、ibutions. Anupdated (July 1982-June 1984) literature survey and evaluation of the data recorded since the publication of the first report (1979). Some references to papers at an international conference held in February 1985 are alsoincluded. This series of reports is intended to aid in the understa
3、nding of the health effects of welding. Performed by: Samual D. Kaplan January, 1986 Abstract This literature review with 105 citations has been prepared for the Safety and Health Committee of the American Welding Society to provide an accessment of current knowledge of the effects of welding on hea
4、lth, as well as to aid in the formation of research projects in this area, as part of an ongoing program sponsored by the Society. Previous work has included studies of the fumes, gases, radiation, and noise generated during various arc welding processes. Referenced materials are available from SRI
5、International. Prepared for SAFETY AND HEALTH COMMITTEE AMERICAN WELDING SOCIETY 550 N.W. LeJeune Road, P. O. Box 351040 Miami, Florida 33135 International Standard Book Number: 0-87 17 1-275-X American Welding Society, 550 N.W. LeJeune Road, P. O. Box 351040, Miami, Florida 33135 1987 by American W
6、elding Society. All rights reserved Printed in the United States of America This report is published as a service and convenience to the welding industry and is the product of an independent contractor (SRI International) which is solely responsible for its contents. The materials in this report hav
7、e not been independently reviewed or verified and are only offered as information. AWS assumes no responsibility for any claims that may arise from the use of this information. Users must make independent investigations to determine the applicability of this information for their purposes. I . Perso
8、nnel AWS Safety and Health Research Committee Dr. A. N. Ward, Chairman K. L. Brown, Vice Chairman M. E. Kennebeck, Jr., Secretary W. T. Delong* G. Hancock* W. S. Howes E. Mastromatteo * R. A. Parent * R. J. Simonton *Advisory Members Caterpillar Tractor Company Lincoln Electric Company American Weld
9、ing Society Teled yne-McKay Bethlehem Steel Corporation NEMA Consultant Consultox, Limited INCO Alloys International . 111 AWS EWH-5 7 07842b5 0005134 2 m Foreword (This Foreword is not is part of the Eflects on Welding on Health - V but is included for information purposes only.) The health of work
10、ers in the welding environment is a major concern of the American Welding Society. To stay abreast of this subject, the health literature is periodically reviewed and published in reports titled Effects of Welding on Health. Four volumes have been published to date, The first covered data published
11、prior to 1978, while the next two covered the periods 1978 to May 1979 and June 1979 to December 1980, respectively. The last of the four included information that was published between December 1980 and June 1982. Ail should be read in conjuction with the current volume for a comprehensive treatmen
12、t of the literature on the effects of welding on health. Included in this volume are studies of the characteristics of welding emissions that may have impact on the control technologies necessary to protect the welding worker (the Exposure). Much recent research has focused on ckomium and nickel, si
13、nce exposure to certain chemical forms of these metals may cause serious chronic health problems. In keeping with previous volumes, the health studies are organized according to the organ system affected (Investiga- tions in Humans). The respiratory tract, the primary route of entry of welding fumes
14、 and gases into the body, also is a major target organ of anumber of components of these emissions. Acute (e.g., metal fume fever, cadmium poisoning) as well as potential chronic respiratory effects (e.g., emphysema, cancer) of welding emissions are of concern. The latter are far less well understoo
15、d and whether or not there is an excess risk of cancer from these exposures has not been established, Continued research in the form of epidemiologic studies, investigations with laboratory animals, and in vitro genotoxicity studies will help to resolve this question (Experimental Investigations). A
16、cknowledgments Funds for this project were provided by American Welding Society. The American Welding Society gratefully acknowledges the financial support of the program by industry contributions. Supporting Organizations Air Products and Chemicals, Incorporated Airco Welding Products Allis-Chalmer
17、s Alloy Rods Division, The Chemetron Corporation AWS Detroit Section AWS New Orleans Section Arcos Corporation The Binkiey Company Caterpillar Tractor Company Chicago Bridge and Iron Company Grove Manufacturing Company, Division of Kidde, Incorporated General Electric Company The Heil Company Hobart
18、 Brothers Company INCO Alloys International Lincoln Electric Company Miller Electric Manufacturing Company National-Standard Company A. O. Smith Corporation Teledyne-McKay, Incorporated Trinity Industries, Incorporated Truck Trailer Manufacturers Association Walker Stainless Equipment Company Weld T
19、ooling Corporation Many other organizations have made contributions to support the ongoing program from May 1979 to the present. AWS EWH-5 87 W 0784265 0005336 b W Comparative Listing - Welding Processes Explanatory Note: Terms used in the technical literature do not correspond to those recommended
20、by AWS in its publication AWS A3.0, Standard Welding Terms and Definitions. Accordingly, the following list will aid the reader in identifying the process in use. EWH - VI Preferred AWS ,Gas or Flame Cutting (OC) Oxygen Cutting Gas Welding (OFW) Oxyfuel Gas Welding MAG (GMAW) - (with specified shiel
21、ding gas) MIG, GMA (GMAW) Gas Metal Arc Welding MMA, SMA (SMAW) Shielded Metal Arc Welding TIG (GTAW) Gas Tungsten Arc Welding Wire Electrode or (OFC) Oxyfuel Gas Cutting or (OAW) Oxyacetylene Welding vi / . I Table of Contents page no . . Personnel . 111 Foreword . iv Acknowledgments . v Comparativ
22、e Listing - Welding Processes . vi Technical Summary 1 1 . The Exposure . 5 1.1 Fumes . 5 1.2 Gases . 9 1.3 Electromagnetic Radiation 10 1.4 Noise 10 1.5 References . 10 2 . Investigations in Humans -11 2.1 Diseases of the Respiratory System . 11 2.2 Metal Fume Fever . 20 2.3 Effects on the Cardiova
23、scular System . 20 2.4 Effects on Kidney Function . 20 2.5 Biological Monitoring 21 2.6 General Morbidity. 23 2.7 Cancer of the Nasopharynx . 24 2.8 Nasal Cancer . 24 2.9 Cancer of the Larynx 25 2.10 Lung Cancer . 27 2.11 Mesothelioma 30 2.12 Bladder Cancer . 31 2.13 Kidney Cancer 31 2.14 Brain Canc
24、er . 31 2.15 Neuroblastoma . 33 2.16 Hodgkins Disease . 33 2.17 References . 34 3 . Experimental Investigations . 37 3.1 Animal Studies 37 3.2 In Vitro Studies 40 3.3 References 42 Technical Summary The Exposure Fumes. A substantial amount of work has been reported on the factors influencing fume fo
25、rmation, including voltage, current, shielding gas, and electrode composition. In a series of reports, Gray et al., have presented data on both total fume formation, fraction- ated (elemental fractions) fume formation rates, and factors that influence thoserates. Other authors (Tandon et al., 1983,1
26、984; and Kobayashiet al., 1981,1983) have also presented substantial bodies of data, The effects of current and voltage appear not to be linear- maxima and minima appear as the voltage and current are increased from minimum acceptable levels through the working range. Tandon also confirmed the empir
27、ical observation that inexperienced welders produce sub- stantially more fume than experienced workers do. Work has continued on the evaluation of methods for chromium analysis. Moreton et al. (1983) presented the results of a major interlaboratory/intermethod round- robin exercise in which several
28、methods for Cr(V1) and Cr(II1) analysis were compared. This topic has also been discussed by others, notably Gray et al. (I983), Stern et al. (1984), and McIlwain and Nuemeier (1983). The reasons for preferential formation of Cr(V1) in fumes and the sampling/ analytical artifacts introduced by some
29、commonly used methods are beginning to be more thoroughly understood, although significant differences of opinion among the active workers in the field are still apparent. Gases. Although gases have not received the recent attention that the fumes have, a fair amount of valuable work has been report
30、ed. Press and Florian (1982), Ditschun (1983); Downey et al. (1983), and Faggetter et al. (1983) have reported on mechanisms of gas forma- I) tion, engineering methods or exposure control, and sampling and analytical methods. Both oxides of nitrogen and ozone have been addressed; the control measure
31、s found to reduce ozone have been addressed; the control measures found to reduce ozone levels have sometimes increased the levels of nitrogen oxides, although promising results in terms of reducing both compounds have been obtained by increasing turbulence in the outer layers of the shield envelope
32、. Electromagnetic Radiation. An interesting finding on the time-course of UV exposure was presented by Eriksen (1985). He found that the initial period of arc ignition may be characterized by an overshoot (as much as ten times the steady-state value) of UV irradiance, leading to eye risks for welder
33、s even though the steady- statevalues werenot excessive. The implications for tack welders and their assistants were pointed out. Noise. Eichbauer and Schmidt (1982) have studied the effects of various welding parameters on noise levels. There are substantial differences between manual metal arc (MM
34、A), GMAW, and gas welding in the effects of such variables as workpiece thickness and form of the weld. Effects of Welding on Human Health Cancer Incidence. Despite the advances made in recent years in studies of the relationship between welding environment and health, gaps in knowledge remain, pos-
35、 sibly because there are few unique or specific diseases caused by the chemical agents associated with welding. Many of the diseases can be related to factors other than chemical in the welding environment; this can confound /- Y AWS EWH-5 7 W 07842b5 0005339 I W 2 the relationship between exposure
36、and the disease that develops. For example, in this review, one important confounding factor for respiratory tract diseases, the smoking history of welders, has not been consistently available to researchers evaluating welding effects. This difficulty can be overcome if the magnitude of the observed
37、 risk is very great or if a dose-response is observed, either as a function of years of welding or as a function of the intensity of the welding tasks. Unfor- tunately, as discussed below, some of the associations observed are very weak, leading some investigators to conclude that some other underly
38、ing factor has been responsible for the increased incidence of cancer observed. Studies that clearly define working conditions, exposure levels, welding materials, and general health of workers, including medical and smoking history, and history of their exposure to asbestos are necessary in order t
39、o separate the possible synergistic effects. An examination of the occupational exposure of weld- ers to chromium and nickel is under way (Waddington et al., 1984). If this study redresses the limitations of pre- vious studies, it may be possible to determine the extent of the health hazard posed by
40、 welding fumes. Cancer of the Nasal Passage. Hernberg et al. (1983a and 1983 b) observed that patients with nasal cancer were more than twice as likely to have an occupational history of welding as patients with cancer of the colon or rectum. Whether this represents a decreased risk of colon/ rectal
41、 cancers or a greatly increased risk of nasal cancer could not be determined from these studies. Cancer of the Larynx. A weak association of welding and all cancers of the larynx was found both by Olsen et al. (1984) and Sjgren and Carstensen (1985). Olsen et al., also found that the risk of cancer
42、of the larynx increased with the number of years of employment as a welder, particularly with the number of hours per week spent welding. Olsen et al., also found a strong associa- tion of welding exposure and the rare subglottic laryn- geal cancer; the increased risk with exposure to welding dust w
43、as seen only in smokers. Lung Cancer. A number of studies have reported either no increase risk of lung cancer or a slight to moderate increase in welders. In a case-control study in Tidewater, Virginia, where shipbuilding had been a major source of employment, Blot et al. (1980), found that a small
44、 excess of cases had worked in a shipyard as a welder or burner. Similar findings of slightly elevated risks among welders were made by Sjgren and Carstensen (1985), Sjgren et al., (1985), and Gallagher and Threifall(l983). In contrast, McMillan and Pethybridge (1983) found no excess risk of lung ca
45、ncer among welders, and only a slight excess risk was observed by Newhouse et al. (1985). Results of some studies in progress may help clarify the relationship of welding and lung cancer and determine whether the increased risk is due to exposure to asbestos, which has previously been proposed as co
46、ntributing to lung cancer. Mesothelioma. Barnes (1983) and McMillan (1983) published case reports of five, and seven welders, respectively. McMillan and Pethybridge (1983) found an increased proportional mortality among welders in ship- yards compared with that in other shipyard workers who are know
47、n to be at increased risk of mesothelioma. However, in each case, asbestos exposure was shown to be responsible for the increased risk. Kidney Cancer. Sjgren and Carstensen (1985) found a weak association with kidney cancer among welders identified during the 1960 Swedish census and sub- sequently f
48、ollowed for cancer. Because the association is weak, it may be explained by a common underlying factor, such as smoking. Brain Cancer. Englund et al. (1982) found a 35 percent excess of observed to expected brain cancer in Swedish welders and gas cutters. In an apparent later follow-up by Sjgren and
49、 Carstensen (1985), this excess had decreased to 20 percent. Because this relatively weak association could be explained by a common underlying factor, further work needs to be done to confirm this finding. Hodgkins Disease. In a proportional mortality analysis of deaths in British Columbia between 1950 and 1978, the deaths among welders from Hodgkins disease were nearly 2.5 times the expected number (Gallagher and Threlfall, 1983). The authors recommended confir- mation of this finding through better designed studies. Diseases of the Respiratory System. McMillan and Pethybrid
