Personal protective equipment for preventing asbestos exposure in workers.

BACKGROUND: Asbestos exposure can lead to asbestos-related diseases. The European Union (EU) has adopted regulations for workplaces where asbestos is present. The EU occupational exposure limit (OEL) for asbestos is 0.1 fibres per cubic centimetre of air (f/cm3) as an eight-hour average. Different types of personal protective equipment (PPE) are available to provide protection and minimise exposure; however, their effectiveness is unclear. OBJECTIVES: To assess the effects of personal protective equipment (PPE), including donning and doffing procedures and individual hygienic behaviour, compared to no availability and use of such equipment or alternative equipment, on asbestos exposure in workers in asbestos demolition and repair work. SEARCH METHODS: We searched MEDLINE, Embase, CENTRAL, and Scopus (September 2022), and we checked the reference lists of included studies. SELECTION CRITERIA: We included studies that measured asbestos concentration outside and inside PPE (considering outside concentration a surrogate for no PPE), exposure to asbestos after doffing PPE, donning and doffing errors, nonadherence to regulations, and adverse effects of PPE. DATA COLLECTION AND ANALYSIS: Two review authors selected studies, extracted data, and assessed risk of bias using ROBINS-I. We categorised PPE as full-face filtering masks, supplied air respirators (SARs), and powered air-purifying respirators (PAPRs). Values for asbestos outside and inside PPE were transformed to logarithmic values for random-effects meta-analysis. Pooled logarithmic mean differences (MDs) were exponentiated to obtain the ratio of means (RoM) and 95% confidence interval (95% CI). The RoM shows the degree of protection provided by the respirators (workplace protection factor). Since the RoM is likely to be much higher at higher outside concentrations, we presented separate results according to the outside asbestos concentration, as follows. • Below 0.01 f/cm3 (band 1) • 0.01 f/cm3 to below 0.1 f/cm3 (band 2) • 0.1 f/cm3 to below 1 f/cm3 (band 3) • 1 f/cm3 to below 10 f/cm3 (band 4) • 10 f/cm3 to below 100 f/cm3 (band 5) • 100 f/cm3 to below 1000 f/cm3 (band 6) Additionally, we determined whether the inside concentrations per respirator and concentration band complied with the current EU OEL (0.1 f/cm3) and proposed EU OEL (0.01 f/cm3). MAIN RESULTS: We identified six studies that measured asbestos concentrations outside and inside respiratory protective equipment (RPE) and one cross-over study that compared the effect of two different coveralls on body temperature. No studies evaluated the remaining predefined outcomes. Most studies were at overall moderate risk of bias due to insufficient reporting. The cross-over study was at high risk of bias. Full-face filtering masks Two studies evaluated full-face filtering masks. They provided insufficient data for band 1 and band 6. The results for the remaining bands were as follows. • Band 2: RoM 19 (95% CI 17.6 to 20.1; 1 study, 3 measurements; moderate certainty) • Band 3: RoM 69 (95% CI 26.6 to 175.9; 2 studies, 17 measurements; very low certainty) • Band 4: RoM 455 (95% CI 270.4 to 765.1; 1 study, 16 measurements; low certainty) • Band 5: RoM 2752 (95% CI 1236.5 to 6063.2;1 study, 3 measurements; low certainty) The inside measurements in band 5 did not comply with the EU OEL of 0.1 f/cm3, and no inside measurements complied with the proposed EU OEL of 0.01 f/cm3. Supplied air respirators Two studies evaluated supplied air respirators. They provided no data for band 6. The results for the remaining bands were as follows. • Band 1: RoM 11 (95% CI 7.6 to 14.9; 1 study, 134 measurements; moderate certainty) • Band 2: RoM 63 (95% CI 43.8 to 90.9; 1 study, 17 measurements; moderate certainty) • Band 3: RoM 528 (95% CI 368.7 to 757.5; 1 study, 38 measurements; moderate certainty) • Band 4: RoM 4638 (95% CI 3071.7 to 7044.5; 1 study, 49 measurements; moderate certainty) • Band 5: RoM 26,134 (16,647.2 to 41,357.1; 1 study, 22 measurements; moderate certainty) All inside measurements complied with the current OEL of 0.1 f/cm3 and the proposed OEL of 0.01 f/cm3. Powered air-purifying respirators Three studies evaluated PAPRs. The results per band were as follows. • Band 1: RoM 8 (95% CI 3.7 to 19.1; 1 study, 23 measurements; moderate certainty) • Band 2: RoM 90 (95% CI 64.7 to 126.5; 1 study, 17 measurements; moderate certainty) • Band 3: RoM 104 (95% CI 23.1 to 464.1; 3 studies, 14 measurements; very low certainty) • Band 4: RoM 706 (95% CI 219.2 to 2253.0; 2 studies, 43 measurements; very low certainty) • Band 5: RoM 1366 (544.6 to 3428.9; 2 studies, 8 measurements; low certainty) • Band 6: RoM 18,958 (95% CI 4023.9 to 90,219.4; 2 studies, 13 measurements; very low certainty) All inside measurements complied with the 0.1 f/cm3 OEL when the outside concentration was below 10 f/cm3 (band 1 to band 4). From band 3, no measurements complied with the proposed OEL of 0.01 f/cm3. Different types of coveralls One study reported the adverse effects of coveralls. A polyethylene suit may increase the body temperature more than a ventilated impermeable polyvinyl (PVC) coverall, but the evidence is very uncertain (MD 0.17 °C, 95% CI -0.08 to 0.42; 1 study, 11 participants; very low certainty). AUTHORS' CONCLUSIONS: Where the outside asbestos concentration is below 0.1 f/cm3, SARS and PAPRs likely reduce exposure to below the proposed OEL of 0.01 f/cm3. For outside concentrations up to 10 f/cm3, all respirators may reduce exposure below the current OEL, but only SAR also below the proposed OEL. In band 5 (10 to < 100 f/cm3), full-face filtering masks may not reduce asbestos exposure below either OEL, SARs likely reduce exposure below both OELs, and there were no data for PAPRs. In band 6 (100 f/cm3 to < 1000 f/cm3), PAPRs may not reduce exposure below either OEL, and there were no data for full-face filtering masks or SARs. Some coveralls may increase body temperature more than others. Randomised studies are needed to directly compare PAPRs and SARs at higher asbestos concentrations and to assess adverse effects. Future studies should assess the effects of doffing procedures.

Cholangiocarcinoma and Occupational Exposure to Asbestos: Insights From the Italian Pooled Cohort Study.

BACKGROUND: Recent studies supported the association between occupational exposure to asbestos and risk of cholangiocarcinoma (CC). Aim of the present study is to investigate this association using an update of mortality data from the Italian pooled asbestos cohort study and to test record linkage to Cancer Registries to distinguish between hepatocellular carcinoma (HCC) and intrahepatic/extrahepatic forms of CC. METHODS: The update of a large cohort study pooling 52 Italian industrial cohorts of workers formerly exposed to asbestos was carried out. Causes of death were coded according to ICD. Linkage was carried out for those subjects who died for liver or bile duct cancer with data on histological subtype provided by Cancer Registries. RESULTS: 47 cohorts took part in the study (57,227 subjects). We identified 639 causes of death for liver and bile duct cancer in the 44 cohorts covered by Cancer Registry. Of these 639, 240 cases were linked to Cancer Registry, namely 14 CC, 83 HCC, 117 cases with unspecified histology, 25 other carcinomas, and one case of cirrhosis (likely precancerous condition). Of the 14 CC, 12 occurred in 2010-2019, two in 2000-2009, and none before 2000. CONCLUSION: Further studies are needed to explore the association between occupational exposure to asbestos and CC. Record linkage was hampered due to incomplete coverage of the study areas and periods by Cancer Registries. The identification of CC among unspecific histology cases is fundamental to establish more effective and targeted liver cancer screening strategies.

Cause specific mortality in an Italian pool of asbestos workers cohorts.

BACKGROUND: Asbestos is a known human carcinogen and is causally associated with malignant mesothelioma, lung, larynx and ovarian cancers. METHODS: Cancer risk was studied among a pool of formerly asbestos-exposed workers in Italy. Fifty-two Italian asbestos cohorts (asbestos-cement, rolling-stock, shipbuilding, and other) were pooled and their mortality follow-up was updated to 2018. Standardized mortality ratios (SMRs) were computed for major causes of death considering duration of exposure and time since first exposure (TSFE), using reference rates by region, age and calendar period. RESULTS: The study included 63,502 subjects (57,156 men and 6346 women): 40% who were alive, 58% who died (cause known for 92%), and 2% lost to follow-up. Mortality was increased for all causes (SMR: men = 1.04, 95% confidence interval [CI] 1.03-1.05; women = 1.15, 95% CI 1.11-1.18), all malignancies (SMR: men = 1.21, 95% CI 1.18-1.23; women = 1.29, 95% CI 1.22-1.37), pleural and peritoneal malignancies (men: SMR = 10.46, 95% CI 9.86-11.09 and 4.29, 95% CI 3.66-5.00; women: SMR = 27.13, 95% CI 23.29-31.42 and 7.51, 95% CI 5.52-9.98), lung (SMR: men = 1.28, 95% CI 1.24-1.32; women = 1.26, 95% CI 1.02-1.53), and ovarian cancer (SMR = 1.42, 95% CI 1.08-1.84). Pleural cancer mortality increased during the first 40 years of TSFE (latency), reaching a plateau thereafter. CONCLUSIONS: Analyses by time-dependent variables showed that the risk for pleural neoplasms increased with latency and no longer increases at long TSFE, consistent with with asbestos clearance from the lungs. Peritoneal neoplasm risk increased over all observation time.

Exploring occupational toxicant exposures in patients with metabolic dysfunction-associated steatotic liver disease: A prospective pilot study.

BACKGROUND: Metabolic dysfunction-associated steatotic liver disease (MASLD) has been traditionally associated with insulin resistance and obesity. Recently, pollutants have been shown to contribute to the development of MASLD. Given the global burden of MASLD, understanding whether pollutants are merely associated with steatosis or contribute to its progression to advanced chronic liver disease (ACLD) and hepatocellular carcinoma (HCC) is critical. Workers exposed to occupational toxicants represent an ideal population for assessing the potentially hazardous consequences of professional exposure. Confirming a link between occupational exposure and ACLD/HCC may not only provide further elements in understanding MASLD, but also contribute to preventive strategies for exposed workers. OBJECTIVE: This study aimed to assess the prevalence of self-reported occupational exposure to toxicants in patients with MASLD. METHODS: This hospital-based prospective pilot study included 201 patients with MASLD. Data on workplace toxicant exposure were collected systematically using a structured questionnaire. Subsequently, patients with ACLD and/or HCC (n = 55) were compared to controls (n = 146). Logistic regression analysis and propensity score models were used to investigate the associations between self-reported occupational exposure and ACLD and/or HCC. RESULTS: Patients with ACLD/HCC reported exposure to metals, halogenated refrigerants, pain/resins, and fuel emissions more often than the controls. After controlling for confounders, durations of 21-30 years and >30 years of occupational exposure to toxicants showed odds ratios (ORs) of 2.31 (95 % confidence interval [CI]: 1.09-4.88, p = 0.029) and 4.47 (95 % CI: 2.57-7.78, p<0.001), respectively. CONCLUSIONS: In this pilot study, patients with MASLD complications were more likely to report workplace toxicant exposure. Our results warrant future multicentre confirmatory studies, as implementing prevention policies may reduce the risk of life-threatening diseases among exposed populations.

Pleural mesothelioma risk in the construction industry: a case-control study in Italy, 2000-2018.

OBJECTIVES: Workers in the construction industry have been exposed to asbestos in various occupations. In Italy, a National Mesothelioma Registry has been implemented more than 20 years ago. Using cases selected from this registry and exploiting existing control data sets, we estimated relative risks for pleural mesothelioma (PM) among construction workers. DESIGN: Case-control study. SETTING: Cases from the National Mesothelioma Registry (2000-2018), controls from three previous case-control studies. METHODS: We selected male PM incident cases diagnosed in 2000-2018. Population controls were taken from three studies performed in six Italian regions within two periods (2002-2004 and 2012-2016). Age-adjusted and period-adjusted unconditional logistic regression models were fitted to estimate odds ratios (OR) for occupations in the construction industry. We followed two approaches, one (primary) excluding and the other (secondary) including subjects employed in other non-construction blue collar occupations for >5 years. For both approaches, we performed an overall analysis including all cases and, given the incomplete temporal and geographic overlap of cases and controls, three time or/and space restricted sensitivity analyses. RESULTS: The whole data set included 15 592 cases and 2210 controls. With the primary approach (4797 cases and 1085 controls), OR was 3.64 (2181 cases) for subjects ever employed in construction. We found elevated risks for blue-collar occupations (1993 cases, OR 4.52), including bricklayers (988 cases, OR 7.05), general construction workers (320 cases, OR 4.66), plumbers and pipe fitters (305 cases, OR 9.13), painters (104 cases, OR 2.17) and several others. Sensitivity analyses yielded very similar findings. Using the secondary approach, we observed similar patterns, but ORs were remarkably lower. CONCLUSIONS: We found markedly increased PM risks for most occupations in the construction industry. These findings are relevant for compensation of subjects affected with mesothelioma in the construction industry.

Asbestos exposure as an additional risk factor for small duct intrahepatic cholangiocarcinoma: a pilot study.

Intrahepatic cholangiocarcinoma (iCCA) is a rare malignancy, recently classified in small duct and large duct morphological subtypes. Growing evidence suggests asbestos as a putative risk factor for iCCA, albeit no correlation between asbestos and iCCA morphology has been investigated so far. The aim of the present study was to assess the relationship between asbestos exposure and iCCA morphological subtype. Forty patients with surgically removed iCCA were prospectively enrolled: asbestos exposure was assessed according to the Italian National Mesothelioma Register questionnaire. From the surgical iCCA specimens the main histopathological variables were collected, including the small duct (sd-iCCA, 32 patients) and large duct subtypes (ld-iCCA, 8 patients). Five sd-iCCA cases had a definite/probable occupational exposure to asbestos, while no cases of ld-iCCA were classified as being occupationally exposed (definite/probable). Other kind of asbestos exposure (i.e. possible occupational, familial, environmental) were recorded in 16 sd-iCCA and 3 ld-iCCA. Cases with unlikely exposure to asbestos were 11 sd-iCCA (35.5%) and 5 ld-iCCA (62.5%). In conclusion, these findings seem to indicate that sd-iCCA might be more frequently associated to asbestos exposure rather than ld-iCCA, suggesting that asbestos fibres might represent a parenchymal, rather than a ductal risk factor for iCCA. This pilot study must be confirmed by further case-control studies or large independent cohorts.

Is Smoking Associated with Carpal Tunnel Syndrome? A Meta-Analysis.

To date, the role of smoking in carpal tunnel syndrome (CTS) is unclear. The aim of this systematic review and meta-analysis was to assess the association between smoking and CTS. The literature searches were conducted in PubMed, Embase, and Scopus, from inception until October 2021. Three reviewers screened the titles, abstracts, and full-text articles and evaluated the methodological quality of the included studies. A random-effects meta-analysis was used, and heterogeneity across studies was examined using I2 statistic. A total of 31 (13 cross-sectional, 10 case-control, and 8 cohort) studies were qualified for meta-analysis. In a meta-analysis of cohort studies, the risk of CTS did not differ between current and never smokers (pooled hazard ratio (HR) 1.09, 95% CI 0.84-1.43), current and past/never smokers (HR 1.07, 95% CI 0.94-1.23), and past and never smokers (HR 1.12, 95% CI 0.83-1.49). Furthermore, a meta-analysis of case control studies found no difference in the risk of CTS between current and never smokers (pooled odds ratio (OR) 0.92, 95% CI 0.56-1.53), current and past/never smokers (OR 1.10, 95% CI 0.51-2.36), and past and never smokers (OR 0.91, 95% CI 0.59-1.39). However, a meta-analysis of cross-sectional studies showed the associations of ever (OR 1.36, 95% CI 1.08-1.72) and current smoking (OR 1.52, 95% CI 1.11-2.09) with CTS. However, the association between ever smoking and CTS disappeared after limiting the meta-analysis to higher quality studies or after adjusting for publication bias. The association between current smoking and CTS also attenuated after limiting the meta-analysis to studies that confirmed CTS by a nerve conduction study or studies with low attrition bias. This meta-analysis does not support an association between smoking and CTS. The association between smoking and CTS observed in cross-sectional studies could be due to biases and/or confounding factors.

Exposure to Asbestos and Increased Intrahepatic Cholangiocarcinoma Risk: Growing Evidences of a Putative Causal Link.

To date the true global incidence of intrahepatic cholangiocarcinoma (iCCA) and the underlying risk factors remain to be fully defined, in particular, the role of occupational and environmental factors. Currently, the putative role of asbestos exposure as a risk factor for iCCA is gaining increased attention in the international scientific community and agencies. In this commentary we review and integrate available epidemiological and mechanistic evidences that support a potential role of asbestos exposure in iCCA etiology.

Authors' response: Mezei et al's "Comments on a recent case-control study of malignant mesothelioma of the pericardium and the tunica vaginalis testis".

Mezei et al's letter (1) is an opportunity to provide more details about our study on pericardial and tunica vaginalis testis (TVT) mesothelioma (2), which is based on the Italian national mesothelioma registry (ReNaM): a surveillance system on mesothelioma, with individual asbestos exposure assessment. Incidence of pericardial mesothelioma has been estimated around 0.5 and 0.2 cases per 10 million person-years in men and women, respectively, and around 1 case for TVT mesothelioma. ReNaM collected 138 cases thanks to its long period of observation (1993-2015) and national coverage. Conducting a population-based case-control study with incidence-density sampling of controls across Italy and over a 23 year time-span should have been planned in 1993 and would have been beyond feasibility and ReNaM scope. We rather exploited two existing series of controls (3). The resulting incomplete time- and spatial matching of cases and controls is a limitation of our study and has been acknowledged in our article. The analysis of case-control studies can nevertheless be accomplished in logistic models accounting for the variables of interest, in both individually and frequency matched studies (4). Furthermore, analyses restricted to (i) regions with enrolled controls, (ii) cases with definite diagnosis, (iii) incidence period 2000-2015, and (iv) subjects born before 1950 have been provided in the manuscript, confirming the strength of the association with asbestos exposure (supplemental material tables S4-7). Following Mezei et al's suggestion, we performed further sensitivity analyses by restriction to regions with controls and fitting conditional regression models using risk-sets made of combinations of age and year of birth categories (5-year classes for both). We confirmed positive associations with occupational exposure to asbestos of pericardial mesothelioma, with odds ratios (OR) (adjusted for region) of 9.16 among women [95% confidence interval (CI) 0.56-150] and 5.63 (95% CI 1.02-31.0) among men; for TVT mesothelioma the OR was 7.70 (95% CI 2.89-20.5). Using risk sets of age categories and introducing year of birth (5-year categories) as a covariate (dummy variables) the OR were similar: OR (adjusted for region) of 9.17 among women (95% CI 0.56-150) and 5.76 (95% CI 1.07-31.0) among men; for TVT the OR was 9.86 (95% CI 3.46-28.1). Possible bias from incomplete geographical overlap between cases and controls has been addressed in the paper (table S4) and above. In spatially restricted analyses, OR were larger than in those including cases from the whole country, indicating that bias was towards the null. Mezei et al further noted that "the regional distribution of controls is different from that of person-time observed". This objection is not relevant because the above analyses were adjusted by region. Our controls were provided by a population-based study on pleural mesothelioma (called MISEM) and a hospital-based study on cholangiocarcinoma (called CARA). In MISEM, the response rate was 48.4%, a low but not unexpected rate as participation among population controls is usually lower and has been declining over time (5). It is important to underline that ReNaM applied the same questionnaire that was used for interviews and carried out the same exposure assessment as both MISEM and CARA. As repeatedly stated in ReNaM papers (6-7), each regional operating center assesses asbestos exposure based on the individual questionnaire, other available information, and knowledge of local industries. Occupational exposure to asbestos is classified as definite, probable or possible. Occupational exposure is (i) definite when the subject`s work was reported or otherwise known to have involved the use of asbestos or asbestos-containing materials (MCA); (ii) probable when subjects worked in factories where asbestos or MCA were used, but their personal exposure could not be documented; and (iii) possible when they were employed in industrial activities known to entail the use of asbestos or MCA. Hence, the definite and probable categories are closer to one another and were combined in our analyses. In any case, restricting analyses to subjects with definite occupational exposure and using each set of controls separately, as suggested by Mezei et al, yielded elevated OR for TVT and pericardial mesothelioma among men using both the above described modelling strategies; the OR could not be calculated for women. There were 70 (25 pericardial and 45 TVT) occupationally exposed mesothelioma cases. In population-based studies, analyses by occupation are limited by the low prevalence of most specific jobs. As briefly reported in our paper, for purely descriptive purposes, the industrial activity of exposure (cases may have multiple exposures), were construction (22 exposures, 7 and 15 for pericardial and TVT mesotheliomas, respectively), steel mills and other metal working industries (4 and 11), textile industries (2 and 3), and agriculture (2 and 5); other sectors had lower exposure frequencies. The absence of industries like asbestos-cement production, shipbuilding and railway carriages production/repair should not be surprising and had already been observed (7). In the Italian multicenter cohort study of asbestos workers (8), given the person-years of observation accrued by workers employed in these industries and gender- and site-specific crude incidence rates, approximately 0.1 case of pericardial and 0.2 of TVT mesothelioma would have been expected from 1970 to 2010. Even increasing ten-fold such figures to account for higher occupational risks among these workers would not change much. Asbestos exposure in agriculture has been repeatedly discussed in ReNaM reports (9: pages 70, 73, 128, 164 and 205). Exposure opportunities included the presence of asbestos in wine production, reuse of hessian bags previously containing asbestos, or construction and maintenance of rural buildings. Similarly, mesothelioma cases and agricultural workers exposed to asbestos have been noted in France (10). In conclusion, the additional analyses we performed according to Mezei et al's suggestions confirm the association between asbestos exposure and pericardial and TVT mesothelioma, supporting the causal role of asbestos for all mesotheliomas. ReNaM`s continuing surveillance system with national coverage is a precious platform for launching analytical studies on pleural and extra pleural mesothelioma. References 1. Mezei G, Chang ET, Mowat FS, Moolgavkar SH. Comments on a recent case-control study of malignant mesothelioma of the pericardium and the tunica vaginalis testis Scand J Work Environ Health. 2021;47(1):85-86. https://doi.org/10.5271/3909 2. Marinaccio A, Consonni D, Mensi C, Mirabelli D, Migliore E, Magnani C et al.; ReNaM Working Group. Association between asbestos exposure and pericardial and tunica vaginalis testis malignant mesothelioma: a case-control study and epidemiological remarks. Scand J Work Environ Health. 2020;46(6):609-617. https://doi.org/10.5271/sjweh.3895. 3. Greenland S. Control-initiated case-control studies. Int J Epidemiol 1985 Mar;14(1):130-4. https://doi.org/10.1093/ije/14.1.130. 4. Pearce N. Analysis of matched case-control studies. BMJ 2016 Feb;352:i969. https://doi.org/10.1136/bmj.i969. 5. Bigert C, Gustavsson P, Straif K, Pesch B, Brüning T, Kendzia B et al. Lung cancer risk among cooks when accounting for tobacco smoking: a pooled analysis of case-control studies from Europe, Canada, New Zealand, and China. J Occup Environ Med 2015 Feb;57(2):202-9. https://doi.org/10.1097/JOM.0000000000000337. 6. Marinaccio A, Binazzi A, Marzio DD, Scarselli A, Verardo M, Mirabelli D et al.; ReNaM Working Group. Pleural malignant mesothelioma epidemic: incidence, modalities of asbestos exposure and occupations involved from the Italian National Register. Int J Cancer 2012 May;130(9):2146-54. https://doi.org/10.1002/ijc.26229. 7. Marinaccio A, Binazzi A, Di Marzio D, Scarselli A, Verardo M, Mirabelli D et al. Incidence of extrapleural malignant mesothelioma and asbestos exposure, from the Italian national register. Occup Environ Med 2010 Nov;67(11):760-5. https://doi.org/10.1136/oem.2009.051466. 8. Ferrante D, Chellini E, Merler E, Pavone V, Silvestri S, Miligi L et al.; the working group. Italian pool of asbestos workers cohorts: mortality trends of asbestos-related neoplasms after long time since first exposure. Occup Environ Med 2017 Dec;74(12):887-98. https://doi.org/10.1136/oemed-2016-104100. 9. ReNaM VI Report. Available from: https://www.inail.it/cs/internet/docs/alg-pubbl-registro-nazionale-mesoteliomi-6-rapporto.pdf. Italian 10. Marant Micallef C, Shield KD, Vignat J, Baldi I, Charbotel B, Fervers B et al. Cancers in France in 2015 attributable to occupational exposures. Int J Hyg Environ Health 2019 Jan;222(1):22-9. https://doi.org/10.1016/j.ijheh.2018.07.015.

The effectiveness of removal from exposure and reduction of exposure for managing occupational asthma: Summary of an updated Cochrane systematic review.

BACKGROUND: The objective was to update the 2011 Cochrane systematic review on the effectiveness of workplace interventions for the treatment of occupational asthma. METHODS: A systematic review was conducted with the selection of articles and reports through 2019. The quality of extracted data was evaluated, and meta-analyses were conducted using techniques recommended by the Cochrane Handbook for Systematic Reviews of Interventions. RESULTS: Data were extracted from 26 nonrandomized controlled before-and-after studies. The mean number of participants per study was 62 and the mean follow-up time was 4.5 years. Compared with continued exposure, removal from exposure had an increased likelihood of improved symptoms and change in spirometry. Reduction of exposure also had more favorable results for symptom improvement than continued exposure, but no difference for change in spirometry. Comparing exposure removal to reduction revealed an advantage for removal with both symptom improvement and change in spirometry for the larger group of patients exposed to low-molecular-weight agents. Also, the risk of unemployment was greater for exposure removal versus reduction. CONCLUSIONS: Exposure removal and reduction had better outcomes than continued exposure. Removal from exposure was more likely to improve symptoms and spirometry than reduction among patients exposed to low-molecular-weight agents. The potential benefits associated with exposure removal versus reduction need to be weighed against the potential for unemployment that is more likely with removal from exposure. The findings are based on data graded as very low quality, and additional studies are needed to generate higher quality data.

Comorbidities, anthropometric, demographic, and lifestyle risk factors for ulnar neuropathy at the elbow: A case control study.

We performed a prospective multicenter case-control study to explore the association between ulnar neuropathy at elbow (UNE) and body and elbow anthropometric measures, demographic and lifestyle factors, and comorbidities. Cases and controls were consecutively enrolled among subjects admitted to four electromyography labs. UNE diagnosis was made on clinical and neurographic findings. The control group included all other subjects without signs/symptoms of ulnar neuropathy and with normal ulnar nerve neurography. Anthropometric measurements included weight, height, waist, hip circumferences, and external measures of elbow using a caliper. The participants filled in a self-administered questionnaire on personal characteristics, lifestyle factors, and medical history. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) by fitting unconditional logistic regression models adjusted by center and education level. We enrolled 220 cases (males 61.8%; mean age 51.7 years) and 460 controls (47.4% males; mean age 47.8 years). At multivariable analysis, UNE was associated to male gender (OR = 2.4, 95%CI = 1.6-3.7), smoking habits (>25 pack-years (OR = 2.3, 95%CI = 1.3-4.1), body mass index (OR = 1.05, 95%CI 1.01-1.10), polyneuropathies (OR = 4.1, 95%CI 1.5-11.5), and leaning with flexed elbow on a table/desk (OR = 1.5, 95%CI 1.0-2.2). Cubital groove width (CGW) turned out to be negatively associated with UNE (OR = 0.80, 95%CI = 0.74-0.85). Our study suggests that some personal factors especially anthropometric measures of the elbow may play a role in UNE pathogenesis as the measures of wrist in CTS. We demonstrated that for each millimeter of smaller CGW the risk of idiopathic UNE increases of 25%.

Association between asbestos exposure and pericardial and tunica vaginalis testis malignant mesothelioma: a case-control study and epidemiological remarks.

Objectives The purposes of this study are to describe the epidemiology of pericardial and tunica vaginalis testis mesothelioma and assess the role of asbestos exposure for these rare diseases. Methods Based on incident pericardial and tunica vaginalis testis mesothelioma cases collected from the Italian national mesothelioma registry (ReNaM) in the period 1993-2015, incidence rates, survival median period and prognostic factors have been evaluated. A case-control study has been performed to analyze the association with asbestos exposure (occupational and non-occupational) for these diseases. Results Between 1993 and 2015, 58 pericardial (20 women and 38 men) and 80 tunica vaginalis testis mesothelioma cases have been registered with a mean annual standardized (world standard population as reference) incidence rates of 0.049 (per million) in men and 0.023 in women for the pericardial site, and 0.095 for tunica vaginalis testis mesothelioma. Occupational exposure to asbestos was significantly associated with the risk of the diseases [odds ratio (OR) 3.68, 95% confidence interval (CI) 1.85-7.31 and OR 3.42, 95% CI 1.93-6.04 in pericardial and tunica vaginalis testis mesothelioma, respectively]. The median survival was 2.5 months for pericardial and 33.0 months for tunica vaginalis testis mesotheliomas. Age was the main predictive factor for survival for both anatomical sites. Conclusions For the first time in an analytical study, asbestos exposure was associated with pericardial and tunica vaginalis testis mesothelioma risk, supporting the causal role of asbestos for all anatomical sites. The extreme rarity of the diseases, the poor survival and the prognostic role of age have been confirmed based on population and nationwide mesothelioma registry data.

Carpal tunnel syndrome in cardiac amyloidosis: implications for early diagnosis and prognostic role across the spectrum of aetiologies.

AIMS: We aimed to assess carpal tunnel syndrome (CTS) prevalence in transthyretin (TTR)-related and light-chain amyloidosis (AL), comparing it to the general population, adjusted for age and gender. In TTR-related amyloidosis (ATTR) we investigated (i) CTS prevalence in relation to genotype, cardiac amyloidosis (CA), age and gender; (ii) CTS role as an incremental risk factor for CA; (iii) temporal relationship between CTS and CA; and (iv) CTS prognostic role. METHODS AND RESULTS: Data from 538 subjects (166 hereditary ATTR, 107 wild-type ATTR, 196 AL amyloidosis, and 69 TTR mutation carriers; 64% male, median age 62.4 years), evaluated at our centre (Bologna, Italy), were analysed and compared to a published cohort of 14.9 million people, in which incidence rates of CTS had been estimated. CTS prevalence was highest in ATTR patients with CA (20.3% vs. 4.1% in the general population), while it was comparable to the general population when CA was absent and in AL patients. CTS standardized incidence rates were markedly elevated in ATTR males in the eighth decade of life (13.08 in hereditary ATTR, 15.5 in wild-type ATTR). The risk of developing CA was greater in ATTR patients with CTS; the probability of having CTS was highest 5-9 years prior to CA diagnosis. CTS was an independent mortality risk factor in ATTR. CONCLUSIONS: Compared to general population the adjusted prevalence of CTS is higher among elderly men with ATTR; CTS is a prognostic marker in ATTR, independently of cardiac involvement, and precedes CA diagnosis by 5-9 years. The awareness of this association and time delay offers the possibility of an early pre-clinical ATTR-CA diagnosis.

Systematic Reviews in Occupational Health and Safety: where are we and where should we go?

Systematic Reviews have been introduced to improve the synthesis of available evidence and to reduce bias in the conclusions about a body of evidence. Nowadays, Systematic Review is an established method also in the Occupational Safety and Health (OSH) field. It is the Cochrane Work Review Group that facilitates authors to produce Cochrane reviews of intervention topics in this area. A variety of guidelines used Cochrane Work reviews for underpinning their recommendations. Due to the comprehensive search and reproducibility of the methods of a systematic review, it turned out that systematic reviews can be powerful in changing beliefs. For example, studies published in the eighties advocated the use of back schools. Nowadays, we know that the total body of evidence has changed the traditional view that training in lifting techniques could prevent back pain. 'Sitting is the new smoking' is an eye catching nicely alliterating motto, but it is of course highly overstated. The findings of a Cochrane review of the effects of interventions to decrease sitting at work showed that sitting time can be reduced by a bit less than two hours per day by providing sit-stand desks plus education. However, it is unclear if this is sufficient to counter the effects of sitting. A wealth of evidence on OSH interventions has been collected by international collaboration in the Cochrane Work Review Group. This can be extended to systematic reviews of the effects of exposure of workers to assess to which risks of adverse health effects they are exposed.

Formaldehyde Exposure and Acute Myeloid Leukemia: A Review of the Literature.

Background and objective: The aim of the present study was to evaluate associations between cumulative and peak formaldehyde exposure and occurrence of acute myeloid leukemia. Material and Methods: A comprehensive search was performed using the PubMed and Embase databases. We included studies presenting information about the role of formaldehyde in leukemic occurrence and mortality risk. Then, full texts of the selected references were assessed, and references of included studies were checked to identify additional articles. Result: The information was then summarized and organized in the present review. A total of 81 articles were obtained from the search. Conclusion: Findings from the review of the literature do not support the hypothesis that formaldehyde is a cause of acute myeloid leukemia.

Role of asbestos clearance in explaining long-term risk of pleural and peritoneal cancer: a pooled analysis of cohort studies.

OBJECTIVES: Models based on the multistage theory of cancer predict that rates of malignant mesothelioma continuously increase with time since first exposure (TSFE) to asbestos, even after the end of external exposure. However, recent epidemiological studies suggest that mesothelioma rates level off many years after first exposure to asbestos. A gradual clearance of asbestos from the lungs has been suggested as a possible explanation for this phenomenon. We analysed long-term trends of pleural and peritoneal cancer mortality in subjects exposed to asbestos to evaluate whether such trends were consistent with the clearance hypothesis. METHODS: We used data from a pool of 43 Italian asbestos cohorts (51 801 subjects). The role of asbestos clearance was explored using the traditional mesothelioma multistage model, generalised to include a term representing elimination of fibres over time. RESULTS: Rates of pleural cancer increased until 40 years of TSFE, but remained stable thereafter. On the other hand, we observed a monotonic increase of peritoneal cancer with TSFE. The model taking into account asbestos clearance fitted the data better than the traditional one for pleural (p=0.004) but not for peritoneal (p=0.09) cancer. CONCLUSIONS: Rates of pleural cancer do not increase indefinitely after the exposure to asbestos, but eventually reach a plateau. This trend is well described by a model accounting for a gradual elimination of the asbestos fibres. These results are relevant for the prediction of future rates of mesothelioma and in asbestos litigations.

Observed Differences between Males and Females in Surgically Treated Carpal Tunnel Syndrome Among Non-manual Workers: A Sensitivity Analysis of Findings from a Large Population Study.

Objectives: We aimed at assessing whether differences among males and females in carpal tunnel syndrome (CTS) epidemiology might be attributable to segregation with respect to occupational biomechanical exposures or differential access to care by sex. Methods: We analysed surgically treated cases of CTS occurring among non-manual workers in Tuscany between 1997 and 2000. We conducted a Monte Carlo simulation to estimate the difference in occupational biomechanical exposures between males and females necessary to explain the observed incidence rate ratios. We also accounted for the sex-specific probability of receiving surgery after the diagnosis of CTS, as women were reported to be more likely to undergo surgery in a subset of our study population. We quantified the hypothetical biomechanical overload through the hand activity level (HAL) metric proposed by the American Conference of Governmental Industrial Hygienists. To quantify the effect of HAL on CTS risk, we assumed a prior distribution based on findings from two large cohort studies of industrial workers. Results: After adjustment for the probability of receiving surgery, women showed a 4-fold incidence of CTS as compared with men. To explain this association among non-manual workers, women should have an average value of HAL at least 5 points higher. Conclusions: Our analysis does not support the hypothesis that the difference in CTS incidence between males and females is entirely attributable to occupational risk factors or to differential access to surgery. The causal pathway between sex and CTS might include more determinants such as hormonal factors, anthropometric characteristics, and non-occupational exposure to biomechanical overload (e.g. household tasks).

Occupational exposure to asbestos and risk of cholangiocarcinoma: a population-based case-control study in four Nordic countries.

OBJECTIVES: To assess the association between occupational exposure to asbestos and the risk of cholangiocarcinoma (CC). METHODS: We conducted a case-control study nested in the Nordic Occupational Cancer (NOCCA) cohort. We studied 1458 intrahepatic CC (ICC) and 3972 extrahepatic CC (ECC) cases occurring among subjects born in 1920 or later in Finland, Iceland, Norway and Sweden. Each case was individually matched by birth year, gender and country to five population controls. The cumulative exposure to asbestos (measured in fibres (f)/ml × years) was assessed by applying the NOCCA job-exposure matrix to data on occupations collected during national population censuses (conducted in 1960, 1970, 1980/81 and 1990). Odds ratios (OR) and 95% CI were estimated using conditional logistic regression models adjusted by printing industry work. RESULTS: We observed an increasing risk of ICC with cumulative exposure to asbestos: never exposed, OR 1.0 (reference category); 0.1-4.9 f/mL × years, OR 1.1 (95% CI 0.9 to 1.3); 5.0-9.9 f/mL × years, OR 1.3 (95% CI 0.9 to 2.1); 10.0-14.9 f/mL × years, OR 1.6 (95% CI 1.0 to 2.5); ≥15.0 f/mL × years, OR 1.7 (95% CI 1.1 to 2.6). We did not observe an association between cumulative asbestos exposure and ECC. CONCLUSIONS: Our study provides evidence that exposure to asbestos might be a risk factor for ICC. Our findings also suggest that the association between ECC and asbestos is null or weaker than that observed for ICC. Further studies based on large industrial cohorts of asbestos workers and possibly accounting for personal characteristics and clinical history are needed.