Metal arc welding and the risk of skin cancer

Abstract

ObjectivesArc welding produces the full spectrum of ultraviolet radiation and may be a contributory cause of skin cancer; however, there has been little research into this occupational hazard. The aim of this study is to explore if metal arc welding increases the risk of malignant melanoma and/or basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) on skin areas which may possibly be exposed (neck, head, and upper extremities).MethodA Danish national company-based historic cohort of 4333 male metal arc welders was followed from 1987 through 2012 to identify the risk of skin cancer. An external reference group was established including all Danish skilled and unskilled male workers with similar age distribution. Occupational histories were gathered by questionnaires in 1986 and information about skin cancer diagnoses [BCC, SCC, cutaneous malignant melanoma (CMM), and precancerous conditions, actinic keratosis (AK)] were gathered from the Danish Cancer Registry supplemented by the data from the Danish Pathology Register. Hazard ratios (HRs) were calculated in the follow-up period from 1987 until 2012 using Cox regression analysis and adjusted for baseline data regarding age and social group.ResultsThe adjusted HR and 95% confidence interval (CI) for skin cancer (all types) were 0.99 (CI 0.94–1.04) for welders. The adjusted HR for AK and BCC located only at neck was 2.49 (CI 1.03–5.99) for welders exposed >20 years (n = 5) and 2.46 (CI 1.02–5.94), respectively, for welders exposed >30 years (n = 5). No statistically significant difference was observed for SCC. The risk of CMM at the neck was also significantly elevated after 30 years of welding, but this is based upon only one exposed case.ConclusionThis study indicates that long-term exposure to metal arc welding may be related to increased risk of BCC and AK located exclusively at the neck. The study provides no support for the hypothesis that welding exposure increases the risk for skin cancer at other locations.

Skin cancer and welding

“…1,7 However, humans can be exposed to UVC from artificial and occupational sources such as welding. 8,9 It is estimated that more than 110 million workers across the world are subject to some form of weldingrelated exposure, whether they are full-time welders or employed in other industries such as construction, farming, ship-building or vehicle servicing. 3,10 Welders are exposed to a number of direct hazards including high heat and radiation, as well as respiratory, cardiovascular and reproductive hazards through inhalation of carcinogenic welding fumes.…”

“…3 It is known that welders are exposed to the full UV spectrum, including UVA, UVB and UVC radiation, artificially from the welding arc. 8,9 Notably, the UVR from the welding arc can result in erythema of unprotected areas of the welder's skin, particularly in the head and neck region, 10 and many welders also experience burns from radiation or flying sparks and hot metal. 11 The severity of such erythema or burns depends on factors such as distance from the source, susceptibility of the host, use of protective clothing, exposure time and wavelength.…”

“…[15][16][17][18] In addition, five case-control studies have been published concerning the potential link between welding and skin cancer ( Table 2). 9,[19][20][21][22] Four of the five studies did not find an increased prevalence of skin cancer in welders. The most recent case-control study was by Heltoft et al, 9 and is the largest and longest casecontrol study investigating the risk of skin cancer in welders.…”

“…9,[19][20][21][22] Four of the five studies did not find an increased prevalence of skin cancer in welders. The most recent case-control study was by Heltoft et al, 9 and is the largest and longest casecontrol study investigating the risk of skin cancer in welders. Unlike in earlier studies, Heltoft et al 9 found a significantly increased risk of BCC in the head and neck region of welders compared with controls [hazard ratio (HR) = 2.49 (95% CI 1.03-5.99) for welders exposed for > 20 years; HR = 2.46 (95% CI 1.02-5.94) for welders exposed for > 30 years].…”

“…The most recent case-control study was by Heltoft et al, 9 and is the largest and longest casecontrol study investigating the risk of skin cancer in welders. Unlike in earlier studies, Heltoft et al 9 found a significantly increased risk of BCC in the head and neck region of welders compared with controls [hazard ratio (HR) = 2.49 (95% CI 1.03-5.99) for welders exposed for > 20 years; HR = 2.46 (95% CI 1.02-5.94) for welders exposed for > 30 years]. However, they found no support for the hypothesis that welding increases skin cancers at other sites (HR = 0.99; 95% CI 0.94-1.04)].…”