Metal arc welding and the risk of skin cancer

Pathogenic mechanisms and etiologic aspects of Mycobacterium avium subspecies paratuberculosis as an infectious cause of cutaneous melanoma

Infectious etiologies have previously been proposed as causes of both melanoma and non-melanoma skin cancer. This exploratory overview explains and presents the evidence for the hypothesis that a microorganism excreted in infected ruminant animal feces, Mycobacterium avium subspecies paratuberculosis (MAP), is the cause of some cases of cutaneous melanoma (CM). Occupational, residential, and recreational contact with MAP-contaminated feces, soil, sand, and natural bodies of water may confer a higher rate of CM. Included in our hypothesis are possible reasons for the differing rates and locations of CM in persons with white versus nonwhite skin, why CM develops underneath nails and in vulvar skin, why canine melanoma is an excellent model for human melanoma, and why the Bacille Calmette-Guérin (BCG) vaccine has demonstrated efficacy in the prevention and treatment of CM. The pathogenic mechanisms and etiologic aspects of MAP, as a transmittable agent underlying CM risk, are carefully deliberated in this paper. Imbalances in gut and skin bacteria, genetic risk factors, and vaccine prevention/therapy are also discussed, while acknowledging that the evidence for a causal association between MAP exposure and CM remains circumstantial.

Occupational exposure to fine particulate matter in the reinforced concrete production and its association with respiratory symptoms and lung function

BACKGROUND

Reinforced concrete production is widespread, but little is known about the occupational exposure to fine particulate matter (PM) in such workplaces, including from metalworking and concrete processing. Therefore, the aim was to characterize exposure to fine PM in the typical workplaces of the whole production cycle and to quantify the risk of respiratory symptoms and lung function in a cohort of reinforced concrete parts production industry.

METHODS

At a reinforced concrete parts producing facility in Almaty, we collected 50 personal PM2.5 samples from the main exposure sites and the measured mass concentrations using gravimetric method. Workers also completed questionnaires on a detailed working history, respiratory symptoms (chronic obstructive pulmonary disease (COPD) Assessment Tool (CAT)), followed by spirometry. The association of cumulative dose with CAT score and forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) was tested with multiple regression.

RESULTS

The highest PM2.5 concentrations were found in the concrete-mixing unit (median 1180 µg/m3), followed by metalworking (510 µg/m3), armature workshop (375 µg/m3) and molding site (245 µg/m3), different from the concentrations in the office (29.5 µg/m3), Kruskall-Wallis p < 0.001. Cumulative PM2.5 dose, mg/m3-year (beta 0.10 (95% confidence interval (CI) 0.05; 0.15)) was strongly associated with CAT score, whereas production with FEV1/FVC (beta -4.96 (-8.31; -1.61)), independent of smoking and chronic bronchitis and sex.

CONCLUSIONS

Mixing concrete and metalworks pose the greatest risk for worker's health in the reinforced concrete production from the inhalational exposure to aerosol, adversely affecting respiratory health.

The sociological basis of the skin cancer epidemic

Given the precipitous rise in its incidence in recent decades, skin cancer has been recognized as a growing epidemic. We explore the sociological underpinnings of this epidemic, including: (1) aging of the demographic; (2) human ecologic factors (residing in areas with high ambient ultraviolet levels and a depleted ozone layer); (3) large-scale European migration to more equatorial latitudes; (4) social structures that for centuries minimized miscegenation and maximized segregation; (5) gender-based differences in sunbathing, tanning, sunscreen use, and clothing choice; (6) occupational ultraviolet exposure; (7) the complex interplay of socioeconomic status, race, and urbanization on skin cancer incidence and mortality; (8) the effects of war on skin cancer incidence; (9) cultural shifts in clothing, travel, outdoor sports, recreation, and attitudes towards being tan; and (10) the indirect effects of religion. We show that without these sociological factors, the most common type of cancer would not be nearly as common.

Photobiological hazards in shielded metal arc welding

PURPOSE

Photobiological hazards caused by artificial optical radiation are assessed for the most commonly used arc welding technique, the SMAW (Shielded Metal Arc Welding), which operates with a hand-held system and is widely used both at occupational and domestic environments, expanding our previous investigation of a robotic arc welding process.

METHODS

The complex exposure limits of the emitted blue and visible light, ultraviolet and infrared, are assessed through the European Directive 2006/25/EC, using three dedicated sensors set to measure irradiance from various typical welding procedures in the controlled environment (currents, electrodes, etc.) of a welding laboratory. In this sense, field measurements are employed, applying existing policies. Occupational limits are also applicable to the domestic welding.

RESULTS

Apart from sub-minute overexposures, which were detected in every spectral band, overexposures in the order of one second were also observed at very close distances, which are common at complex working environments. Investigation of the initial welding procedure, which is often performed without the use of Personal Protective Equipment, revealed exposure of the order of the corresponding limit.

CONCLUSIONS

Simulation of a 'bad' welding procedure revealed increased exposure, indicating the importance of training in the occupational environment. Concern for the exposure of near-by workers (working a few meters away from the welding point) is also crucial. Future work needs to incorporate more welding techniques and measurements from original workplaces, in order to set the basis for an integrated risk assessment and provide valuable information concerning occupational diseases.

Advances in Photodynamic Therapy for the Treatment of Actinic Keratosis and Nonmelanoma Skin Cancer: A Narrative Review

Photodynamic therapy (PDT) with photosensitization using 5-aminolevulinic acid (ALA) [including a nanoemulsion (BF-200 ALA)] is approved in the USA for the treatment of actinic keratoses (AKs); another derivative, methyl aminolevulinate, is not approved in the USA but is used in Europe. For AK treatment, the photosensitizer may be applied to individual AK lesions or, depending on treatment regimen, to broader areas of sun-damaged skin to manage field cancerization, although not all products are approved for field treatment. ALA-PDT and photosensitizers have also been used off-label for the treatment of nonmelanoma skin cancers, primarily basal cell carcinomas (BCCs) and cutaneous squamous cell carcinomas (cSCC). Advantages of PDT include potentially improved cosmesis and patient satisfaction; disadvantages include pain and duration of treatment. Alternative illumination approaches, including intense pulsed light as well as pulsed-dye lasers, have also been used successfully. Pretreating the affected tissue or warming during incubation can help to increase photosensitizer absorption and improve therapeutic efficacy. Combinations of multiple treatments are also under exploration. Reducing incubation time between photosensitizer application and illumination may significantly reduce pain scores without affecting treatment efficacy. Substituting daylight PDT for a conventional illumination source can also reduce pain without compromising efficacy. The objective of this narrative review is to describe current and ongoing research in the use of topical photosensitizers and modified light delivery regimens to achieve improved therapeutic outcomes with less toxicity in patients with AK, cSCC, BCC, and field cancerization.

Occupational electromagnetic spectrum hazards and the significance of artificial optical radiation: country report for Greece

BACKGROUND

The electromagnetic spectrum spans over an enormous range from 0 up to more than 1020 Hz in the deep ionizing region, significant exposures exist in specific occupational environments. Between the ionizing and the electromagnetic fields (EMF) part of the spectrum, the 'optical radiation' (OR) region has specific properties. Comparative and concise evaluation enables action prioritization.

METHODS

Following the transposition and implementation periods of the artificial optical radiation (AOR) and EMF European Directives, the Hellenic Ministry of Labour in collaboration with the Greek Atomic Energy Commission (EEAE) and the National Technical University of Athens, conducted thorough occupational exposure investigation in Greece. Using dedicated measuring equipment and procedures, the majority of EMF emitting installations in Greece and also AOR emitting installations including arc welding, lasers and PC monitors has been assessed.

RESULTS

Measurement results from occupational settings reveal that it is the non-coherent metal arc welding AOR that can pose even sub-second overexposures. Rare EMF overexposures are manageable and EMF concern is not justified. Maintenance procedures demand proper attention. Preliminary laser safety assessment reveals OHS gaps and potential eye and skin hazards. Blue light exposure from computer monitors is well below safety limits.

CONCLUSIONS

This electromagnetic spectrum risk assessment conducted in Greece enables the justification of the real occupational hazards, in this sense: i) EMF exposure assessment has to be concentrated to maintenance procedures; ii) AOR measuring setups are challenging and standardized measurement procedures are missing, and iii) AOR overexposures from arc welding pose significant eye and skin hazards.

Cytokinesis-block micronucleus cytome (CBMN-CYT) assay and its relationship with genetic polymorphisms in welders

Fumes generated in the welding process are composed of micrometric and nanometric particles that form when metal fumes condense. The International Agency for Research on Cancer established that many compounds derived from the welding process are carcinogenic to humans. Still, there are few studies related to the role of genetic polymorphisms. This work aimed to analyze the influence of OGG1 Ser326Cys, XRCC1 Arg280His, XRCC1 Arg194Thr, XRCC1 Arg399Gln, XRCC3 Thr241Met, GSTM1, and GSTT1 gene polymorphisms on DNA damage of 98 subjects occupationally exposed to welding fumes and 100 non exposed individuals. The results showed that individuals exposed to welding fumes with XRCC3 Thr241Thr, XRCC3 Thr241Met, and GSTM1 null genotypes demonstrated a significantly higher micronucleus frequency in lymphocytes. In contrast, individuals with XRCC1 Arg399Gln and XRCC1 Gln399Gln genotypes had significant levels of NPBs. OGG1 326 Ser/Cys, OGG1 326 Cys/Cys, XRCC1 194Arg/Thr, XRCC1 194Thr/Thr, and GSTT1 null genotypes exhibited significantly higher apoptotic values. Also, XRCC1 194Arg/Trp, XRCC1 194Thr/Thr, and GSTM1 null genotype carriers had higher necrotic levels compared to XRCC1 194Arg/Arg and GSTM1 nonnull carriers. Compositional analysis revealed the presence of iron, manganese, silicon as well as particles smaller than 2 μm that adhere to each other and form agglomerates. These results may be associated with a mixture of components, such as nitrogen dioxide, carbon monoxide, and metallic fumes, leading to significant DNA damage and cell death processes. These findings demonstrated the importance of the association between individual susceptibility and DNA damage levels due to occupational exposure to welding fumes; and constitute one of the first studies carried out in exposed workers from Colombia.

Relation between personality dimensions and symptomatology of depression in skin cancer patients

BACKGROUND

Environmental psychological factors such as mood states can modify and trigger an organic response; depressive disorder is considered a risk factor for oncological development, leading to alterations both in the genesis and in the progression of the disease. Some authors have identified that personality relates to mood since a high score in neuroticism is associated with intense and long-lasting emotions of stress and therefore with the development of depressive behaviors. The objective of this study was to analyze the relationship between personality and depression in skin cancer patients.

METHODS

A total of forty-seven clinically and histopathologically diagnosed patients were scheduled for an hour-long interview, during which they provided informed consent and sociodemographic information. The psychological questionnaires applied were the revised Eysenck Personality Questionnaire and the clinical questionnaire for the diagnosis of the depressive syndrome.

RESULTS

The patient's mean age was 66.5 years (SD ± 12.4) and the majority were diagnosed with basal cell carcinoma (70.2%). The frequency of anxious/depressive symptoms was 42.5%, with an increase in depression scores in the female gender (p < 0.001). Furthermore, a difference was found in the neuroticism dimension related to gender, with higher values in women (p = 0.002). Depressive symptomatologic portraits were correlated with the dimensions of neuroticism (p < 0.001, r = 0.705), psychoticism (p = 0.003, r = 0.422) and lying (p = 0.028, r = - 0.321).

CONCLUSIONS

Our results support the hypothesis that personality dimensions are related to the presence of anxiety/depressive symptomatology in patients with skin cancer, especially in the female gender. Highlighting the need for future research that delves into the implications at the psychological level, the quality of life, and the biological mechanisms that link personality and depressive symptoms in the development and evolution of skin cancer.

Ultraviolet Radiation and Basal Cell Carcinoma: An Environmental Perspective

Ultraviolet radiation (UVR) is a known carcinogen participated for the development of skin cancers. Solar UVR exposure, particularly ultraviolet B (UVB), is the mostly significant environmental risk factor for the occurrence and progress of basal cell carcinoma(BCC). Both cumulative and intermittent high-grade UVR exposure could promote the uncontrolled replication of skin cells. There are also exsiting other contributing environmental factors that combine with the UVR exposure to promote the development of BCC. DNA damage in formation of skin cancers is considered to be a result of UVR toxicity. It is UVR that could activate a series of oncogenes simultaneously inactivating tumor suppressor genes and aberrant proliferation and survival of keratinocytes that repair these damages. Furthermore, mounting evidence demonstrates that inflammatory responses of immune cells in the tumor microenvironment plays crucial role in the skin tumorigenesis as well. In this chapter, we will follow the function of UVR in the onset and development of BCC. We describe the factors that influence BCC induced by UVR, and also review the recent advances of pathogenesis of BCC induced by UVR from the genetic and inflammatory aspects.

Ignition of Welding Arc and UV Actinic Hazard Evaluation

Welding arcs emit strong ultraviolet (UV) radiation, which could pose serious health risks for skin and eyes. According to Directive 2006/25/EC, UV hazard evaluation has to be performed in the working environment. The measurement of welding arc ignition radiation is a difficult task. This article describes the effort made to determine actinic radiant exposure levels during welding arc ignition in the controlled environment of a welding laboratory. A new method of UV actinic hazard evaluation from welding arc ignition radiation using a CCD spectroradiometer combined with a photometer is presented. The hazard of UV emitted in pulsed metal active gas welding (MAG-P) of construction steel is described. The duration of ignition peak in the study was in the range of 9–15 ms. The actinic radiant exposure during arc ignition over aversion response time was in the range of 0.26–1.12 J/m2. The daily exposure time can easily exceed the permissible exposure time obtained in our study, i.e., 13–34 s, which means that UV radiation form MAG-P arc welding is hazardous for workers in the vicinity of the welding arc. The measurement method presented in the article enables determination of radiant exposure of arc ignition radiation.

Skin cancer and welding

Many workers in several different occupations can be exposed to ultraviolet radiation (UVR), which may increase their risk of developing skin cancer. Welding, an occupation employing an estimated 11 million people worldwide, is one such occupation. Welders are known to be exposed to the full spectrum of UVR from the welding arc and often experience burns and localized cutaneous erythema. In 2017, UVR from welding was classified as carcinogenic to humans based on sufficient evidence of ocular melanoma in humans. It has been hypothesized that exposure to UVR from the welding arc also may increase the risk of skin cancer among workers in this occupation. This review summarizes the current literature on skin cancer risk in welders.

UV exposure, preventive habits, risk perception, and occupation in NMSC patients: A case-control study in Trieste (NE Italy)

BACKGROUND

UV exposure is strongly associated with the incidence of non melanoma skin cancers (NMSCs), both basal and squamous cell carcinomas. The aim of our study was to analyze risk perception, UV exposure, preventive habits, and occupation in 126 subjects affected by NMSC and 187 controls.

METHODS

Consecutive cases with incident NMSC were recruited in Dermatologic Unit at University of Trieste; controls were recruited in Unit of Occupational Medicine. All had a medical examination to define Fitzpatrick skin type and skin lesions, and filled a standardized questionnaire on sun exposure habits, sun protection, occupational exposures, and sunburns in adulthood and childhood.

RESULTS

In multivariate regression analysis, NMSC resulted significantly associated with age (OR: 1.03; 95% CI 1.01-1.05), with a positive feeling for tan (OR: 1.10; 95% CI 1.01-1.20), and sunbath numbers per year (OR: 1.02; 95% CI: 1.001-1.03). A protective effect was demonstrated for Fitzpatrick phototypes III-IV compared to I and II (OR: 0.31; 95% CI: 0.18-0.55), sunscreen use (OR: 0.35; 95% CI: 0.22-0.58), and risk perception (OR: 0.98; 95% CI: 0.97-0.99). In univariate analysis, we demonstrated an increased risk for fishermen, sailors, and lifeguards (OR: 4.3; 95% CI: 1.1-16.4); foundry and metallurgy workers (OR: 5.58; 95% CI: 1.14-27.3); and mechanics, fixers, and welders (OR: 8.2; 95% CI: 1.76-37.9).

CONCLUSIONS

Our study demonstrated that protective behavior must be implemented in people living in Trieste. Workers must avoid direct UV exposure and must use protective equipment. More efforts are needed to increase knowledge on this risk and to raise awareness among at-risk people.