Can single-use versus standard duodenoscope improve ergonomics in ERCP? A comparative, simulation-based pilot study.

Background and study aims Musculoskeletal disorders (MSDs) and injuries (MSIs) are frequent in gastrointestinal endoscopy. The aim of this study was to assess potential ergonomic advantages of a lighter single-use duodenoscope compared with a standard reusable one for endoscopists performing endoscopic retrograde cholangiopancreatography (ERCP). Methods Three experienced endoscopists performed an ergonomic, preclinical, comparative protocol-guided simulation study of a single-use and a standard reusable duodenoscope using an anatomic bench model. Surface EMG signals from left forearm and arm muscles were recorded. A commercial inertial sensor-based motion capture system was applied to record body posture as well. Results A significant lowering of root mean square amplitude and amplitude distribution of biceps brachii signal (ranging from 13% to 42%) was recorded in all the participants when using a single-use duodenoscope compared with a reusable one. An overall reduction of muscle activation amplitude and duration was also associated with the single-use duodenoscope for forearm muscles, with different behaviors among subjects. Participants spent most of the time in wrist extension (> 80%) and ulnar deviation (> 65%). A consistent pattern of functional range of motion employed for completing all procedures was observed. Conclusions Our study showed that a lighter scope has a promising effect in reducing upper arm muscle activity during ERCP with potential benefit on musculoskeletal health in the ERCP setting.

Quantitative Assessment of Asbestos Fibers in Abdominal Organs: A Scoping Review.

BACKGROUND: Quantification of asbestos fibers has been mainly performed in the lung but rarely in other organs. However, this may be relevant to understanding better translocation pathways and the oncogenic effects of asbestos on the human body. Electron microscopy is the best technology available to assess the type of fiber, dimensions, and distribution of asbestos fibers in different tissues and as a biomarker of cumulative dose. OBJECTIVES: This scoping review aims to summarize the findings of the studies in which asbestos fibers have been quantified by electron microscopy, occasionally associated with X-ray microanalysis, in normal and pathological tissue of ten abdominal organs. METHODS: A scoping review has been performed by searching articles that quantified asbestos fibers in abdominal organs by electron microscopy (Scanning- SEM or Transmission- TEM). RESULTS: The 12 selected studies included 204 cases, and 325 samples were analyzed. The colon and rectum, kidney, bladder, and abdominal lymph nodes were the organs with at least ten samples available with quantification of asbestos fibers. Asbestos fibers were detected in all the abdominal organs considered: the highest value (152,32 million fibers per gram of dry tissue) was found in the colon and was identified using STEM with EDS. CONCLUSION: The studies included were heterogeneous in terms of exposure and cases, type of samples, as well as analytical techniques, therefore we cannot confirm a specific pattern of distribution in any organ, based on the low homogeneity of the exposure status. The colon is the organ in which the number of fibers is the highest, probably because of exposure arising from both internal distribution of inhaled fibers and ingestion. Additional studies of the number of asbestos fibers in abdominal organs should be made to achieve better representativity.

Quantitative assessment of asbestos fibers in some normal and pathological extra-abdominal tissues-a scoping review.

BACKGROUND: Asbestos is a mineral present in nature and it has been used for years in numerous settings. Asbestos enters the bloodstream and lymphatic system mainly through breathing. OBJECTIVES: Studies with asbestos fiber's quantification in human tissues are scarce except for the lung. This article summarizes asbestos studies in some extra-abdominal tissues. METHODS: A scoping review of articles that quantified asbestos fibers in extra-abdominal tissues (lymph nodes, pharynx, larynx, trachea, heart) by electron microscopy (Scanning-SEM or Transmission-TEM) was performed. RESULTS: The 10 studies selected comprised 52 cases, out of whom 108 samples were analyzed. Mostly samples were lymph node tissues (102), followed by larynx (3) and myocardium (3). No studies were found that determined the presence of asbestos in the pharynx or trachea. The concentration of asbestos fibers detected in the lymph nodes was from 0.003 million fibers per gram of dry tissue (mfgdt) up to 7400 mfgdt, in the larynx the range was from 0.5 mfgdt up to 3.6 mfgdt, in myocardium no asbestos fibers were detected. DISCUSSION: The studies included were heterogeneous in terms of case and sample characteristics and analytical techniques. As subjects exposed to asbestos are often positive for fibers in thoracic lymph nodes, we suggest that whenever a human tissue sample is analyzed for asbestos presence, the relevant draining lymph node should be concomitantly studied.

[Occupational safety and health risks in seaport: an update of narrative review]. / I rischi per la salute e la sicurezza nel lavoro portuale: aggiornamento della revisione narrativa della letteratura.

SUMMARY: Seaports are complex systems in which workers can be exposed to a large variety of safety and health risks. Nevertheless, a little literature is available concerning this topic, if we exclude the specific area of shipbuilding industry. Objectives. The aim of this paper is to update the review of the scientific literature previously published as result of a project concerning the occupational risks in seaports. Methods. Literature on this theme, obtained consulting the main databases (PubMed, Scholar and CCOHS) from 2012 and up to April 2019, was reviewed. Results. 5 of 8 articles published after 2012 were related to risk of release or formation of volatile compounds in restricted and poorly ventilated areas or inhalation of particles from specific goods. Three papers specifically debated musculoskeletal disorders related to loading/unloading procedures, occupational diseases and injuries. Conclusions. The update of the literature highlighted intrinsically dangerous goods, toxic volatile compounds and emissions as critical aspects of seaport activities related to goods handling. Recently, the literature shows a growing interest in occupational health, especially work-related musculoskeletal diseases. Prevention measures and implementation of worker's training and information are identified by all authors as the more effective action to increase health and safety..

Knee osteoarthritis in a chestnut farmer - Case Report.

INTRODUCTION: Several studies have dealt with the issue of professional risk factors and onset of knee osteoarthritis (OA). In particular, occupational epidemiological studies have provided evidence that activities resulting in biomechanical overload may be linked with an increased risk of knee OA - also among farmers. To our knowledge, no cases of knee OA among chestnut farmers have been reported in the literature. CASE REPORT: We report the case of a 70-year-old Caucasian male who has worked for more than 50 years on a chestnut farm. In 2007, an X-ray and a MRI, performed after a workplace accident to his left knee, showed the presence of knee OA. His job required a range of repetitive tasks, such as squatting, kneeling, climbing, walking on sloping terrain, assuming uncomfortable postures, and lifting and carrying heavy loads for the great majority of the working day. All the aforementioned tasks are known occupational risk factors for knee OA. Regarding individual risk factors, at the time of the first diagnosis of knee OA, the worker was 64-years-old with a body mass index of 26.5 kg/m2. He reported no cases of arthritis among his relatives and no sports playing on his part. In addition, his medical history revealed the presence of two minor lumbar disc herniations and tendinitis of the long head of the biceps. CONCLUSION: Considering the lack of major individual risk factors for knee OA, it is reasonable to suppose that five decades of exposure to biomechanical overload as a chestnut farmer was a relevant risk factor for the onset of the disease.

Carpal tunnel syndrome and manual work: the OCTOPUS cohort, results of a ten-year longitudinal study.

OBJECTIVE: The American Conference of Governmental Industrial Hygienists (ACGIH) proposed a method to assess the hand, wrist and forearm biomechanical overload based on exertions frequency (hand-activity level) and force use (normalized peak force). We applied the ACGIH threshold limit value (TLV)® method to a large occupational cohort to assess its ability to predict carpal tunnel syndrome (CTS) onset. METHODS: A cohort of industrial and service workers was followed-up between 2000 and 2011. We investigated the incidence of CTS symptoms and CTS confirmed by nerve conduction studies (NCS). We then classified exposure with respect to action limit (AL) and TLV. Cox regression models including age, gender, body mass index, and presence of predisposing pathologies were conducted to estimate hazard ratios (HR) of CTS and population attributable fractions. RESULTS: We analyzed data from 3131 workers [females, N=2032 (65%); mean age at baseline 39.3, standard deviation (SD) 9.4 years]. We observed 431 incident cases of CTS symptoms in 8000 person-years and 126 cases of CTS confirmed by NCS in 8883 person-years. The ACGIH TLV® method predicted both CTS symptoms [HR between AL and TLV 2.18, 95% confidence interval (95% CI) 1.86-2.56; above TLV 2.07, 95% CI 1.52-2.81] and CTS confirmed by NCS (HR between AL and TLV 1.93, 95% CI 1.38-2.71; above TLV 1.95, 95% CI 1.27-3.00). About one third of CTS cases were attributable to exposure levels above the AL. CONCLUSIONS: The ACGIH TLV® method predicted the risk of CTS, but the dose-response was flat above the AL; a fine-tuning of the proposed thresholds should be considered.

[Occupational safety and health risks in dock work: a narrative literature review. ]. / I rischi per la salute e la sicurezza nel lavoro portuale: revisione narrativa della letteratura.

BACKGROUND: Seaports are complex systems where workers can be exposed to a large variety of safety and health risks. Nevertheless, the literature available on this topic is scarce, if we exclude the specific area of the shipbuilding industry. OBJECTIVES AND METHODS: The aim of this paper is to provide a review of the scientific evidence concerning the occupational risks in seaports. Literature on this theme, obtained consulting the main databases (PubMed, Scholar and CCOHS) up to 2012, was reviewed. RESULTS: Loading/unloading procedures, transport and storage of goods in docks are identified as the major causes of injuries (such as falls, crushing and entrapments) and accidents (release of chemicals, fires or explosions). Moreover, attention is drawn to the risks related to goods handled: in particular, authors described risks of asphyxia or intoxication in restricted and poorly ventilated areas such as containers or ship holds. CONCLUSIONS: The following main prevention measures were identified by all authors as those most effective: implementation of workers' training and information and intensification of controls on ships, particularly concerning loading/unloading procedures and documents accompanying the goods.

[Occupational risks in grocery stores]. / Rischi da lavoro nella grande distribuzione.

AIM: This work provides an overview of the spectrum of possible occupational risk factors in the retail grocery store/supermarket workplace. METHOD: Literature on this theme, obtained consulting PubMed database and Google Scholar, was checked. We also exjlore results from the National bInstitute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA). RESULTs: Contacts with objects, use of dangerous equipment (cutter, food slicer) and falls to the same level (slips, trips and falls) are the mainly described workplace hazards. Exposure to chemical (flour dust, components of detergents or disinfectants, volatile organic compounds and contact with nickel) and physical agents (cold exposure, nonionizing radiation and whole bpdy vibration) are reported by many authors. Relations between biomechanical and ergonomic risk factors and musculoskeletal disorders represent the main subjects of study. Few studies are found about biological agents (particularly among butchers). Data regarding psychosocial risks factors in this setting are still limited. CONCLUSIONS: Musculoskeletal disorders continue to be the most recurrent health problem between the grocery store workers (particularly low back pain and carpal tunnel syndrome among cashiers). Many technical documents and international Srecommendations are present to prevent these kinds of disorders. Psychosocial risk factors and risk of workplace violence should deserve further investigation.

[Risk assessment comparison of biomechanical overloading of the musculoskeletal system: 10 years' applied experience]. / Metodi di valutazione del rischio da sovraccarico biomeccanico all'apparato muscolo scheletrico a confronto: esperienza applicativa di dieci anni.

UNLABELLED: Risk assessment for upper extremity work related muscoloskeletal disorders by applying six methods of ergonomic: a ten years experience. The objective of this research was to verify and validate the multiple step method suggested by SIMLII guidelines and to compare results obtained by use of these methods: Washington State Standard, OCRA, HAL, RULA, OREGE and STRAIN INDEX. METHODS: 598 workstations for a total of 1800 analysis by different methods were considered, by adopting the following multiple step procedure: prelinminary evaluation by Washington State method and OCRA checklist in all the working stations, RULA or HAL as first level evaluation, OREGE or SI as second level evaluation. RESULTS: The preliminary evaluation resulted negative (risk absent) in the 75% of examined work stations and by using checklist OCRA optimal-acceptable condition was found in 58% by HAL in 92% of analysis, by RULA in 100%, by OREGE in 64%; by SI in 70% of examined working positions. We observed similar evaluation of strain among methods and main differences have been observed in posture and frequency assessment. DISCUSSION AND CONCLUSION: The preliminary evaluation by State of Washington method appears to be an adequate instrument for identify the working condition at risk. All the adopted methods were in a good agreement in two estreme situations: high risk or absent risk, expecially in absent risk conditions. Level of accordance varied on the basis of their rationale and of the role of their different components so SIML indications about the critical use of biouzechanical methods and about the possible use of more than one of them (considering working chlaracteristics) have been confirmed.

Effects of 90 min of manual repetitive work on skin temperature and median and ulnar nerve conduction parameters: a pilot study in normal subjects.

To test whether the influence of manual activity should be considered when interpreting the results of nerve conduction study (NCS) of the upper limbs performed during work shifts, we evaluated the short-term effect of 90-min repetitive manual work on NCS parameters. Twenty-eight healthy volunteers underwent NCS of the dominant limb at the end of an interview (T(0)), after a 30-min rest in sitting position (T(1)) and after performing a standardized 90-min manual task (T(2)). The task was designed to simulate typical assembly and packing activities. No significant differences were observed for skin temperature (Ts) and NCS parameters between T(0) and T(1). Significantly (p < 0.001) higher Ts mean values were found at T(2) as compared to the previous tests for both females and males. The regression analysis showed an association between temperature variation and nerve conduction velocity values for the median and ulnar nerve at T(2) as compared to T(1). In females, a reduction of the mean sensory nerve action potential (SNAP) amplitude at T(2) was recorded, whereas an opposite trend was observed among males. Manual work is able to influence hand Ts and to modify NCS parameters. SNAP amplitudes changes suggest gender differences in peripheral nerve characteristics that deserve further investigation.

Validation of the ACGIH TLV for hand activity level in the OCTOPUS cohort: a two-year longitudinal study of carpal tunnel syndrome.

OBJECTIVES: This study aimed to evaluate the risk of musculoskeletal disorders to the hand-wrist system. The American Conference of Governmental Industrial Hygienists (ACGIH) proposed threshold limit values (TLV©) based on hand activity level (HAL) and normalized peak force (PF). We validated ACGIH TLV© in OCTOPUS, a large cohort study on carpal tunnel syndrome (CTS). METHODS: Industrial and service workers were followed from 2000-2003. We classified subjects with respect to action limit (AL) and TLV. Case definitions were: (i) self-reported symptoms; and (ii) combination of symptoms and positive nerve conduction studies. Poisson regression models including age, gender, body mass index, and presence of predisposing pathologies were conducted to estimate incidence rate ratios (IRR) of CTS. RESULTS: There were 4097 eligible workers. Of these, 236 (5.8%) were non-responders, 2194 (53.6%) had a complete follow-up, 728 (17.8%) were lost after intermediate assessment, and 939 (22.9%) were lost after baseline. Among the 3860 subjects with complete information at baseline, 2599 (67.3%) were women [mean age 38.1 [standard deviation (SD) 9.5] years; mean body mass index (BMI) 23.8 (SD 3.9) kg/m2]. ACGIH TLV© classification predicted both CTS symptoms [IRR between AL and TLV 2.43 [95% confidence interval (95% CI) 1.77-3.33]; above TLV 3.32 (95% CI 2.34-4.72)] and CTS confirmed by nerve conduction studies [IRR between AL and TLV 1.95 (95% CI 1.21-3.16); above TLV 2.70 (95% CI 1.48-4.91)]. CONCLUSIONS: We found a dose-response relationship between ACGIH TLV© classification and risk of CTS. The increased risk observed for workers exposed between AL and TLV suggests that the current AL and TLV might not be sufficiently protective.

A case report of vibration-induced hand comorbidities in a postwoman.

BACKGROUND: Prolonged exposure to hand-transmitted vibration is associated with an increased occurrence of symptoms and signs of disorders in the vascular, neurological and osteoarticular systems of the upper limbs. However, the available epidemiological evidence is derived from studies on high vibration levels caused by vibratory tools, whereas little is known about possible upper limb disorders caused by chronic exposure to low vibration levels emitted by fixed sources. CASE PRESENTATION: We present the case of a postwoman who delivered mail for 15 years using a low-powered motorcycle. The woman was in good health until 2002, when she was diagnosed with bilateral Raynaud's phenomenon. In March 2003 a bilateral carpal tunnel syndrome was electromyographically diagnosed; surgical treatment was ineffective. Further examinations in 2005 highlighted the presence of chronic tendonitis (right middle finger flexor). RISK ASSESSMENT: From 1987, for 15 years, our patient rode her motorcycle for 4 h/day, carrying a load of 20-30 kg. For about a quarter of the time she drove over country roads. Using the information collected about the tasks carried out every day by the postwoman and some measurements performed on both handles of the motorcycle, as well as on both iron parts of the handlebars, we reconstructed the woman's previous exposure to hand-arm vibration. 8-hour energy-equivalent frequency weighted acceleration was about 2.4 m/s². The lifetime dose was 1.5 × 109(m²/s4)hd. CONCLUSIONS: The particular set of comorbidities presented by our patient suggests a common pathophysiological basis for all the diseases. Considering the level of exposure to vibrations and the lack of specific knowledge on the effects of vibration in women, we hypothesize an association between the work exposure and the onset of the diseases.

Exposure to low environmental levels of benzene: evaluation of micronucleus frequencies and S-phenylmercapturic acid excretion in relation to polymorphisms in genes encoding metabolic enzymes.

An integrated approach based on environmental and biological monitoring, including the analysis of biomarkers of exposure [excretion of S-phenylmercapturic acid (S-PMA)], early biological effects [micronucleus (MN) frequency] and susceptibility (genetic polymorphisms), was applied to characterize benzene exposure in a group of 70 traffic policemen and 40 employees of the city of Bologna, Italy. Median personal benzene exposure was 6.55-fold higher for traffic policemen than for controls (P<0.0001). This higher exposure was confirmed by a significant, 2.53-fold higher S-PMA excretion in traffic policemen compared with that observed for indoor workers (P<0.0001). Median MN frequency was also significantly higher in policemen compared with indoor workers (P=0.001), emphasizing the genotoxic effect potentially associated with benzene exposure. With regard to biomarkers of susceptibility, the analysis revealed that high epoxide hydrolase (mEH) (predicted) enzyme activity was significantly correlated with a lower median MN frequency (P=0.003). A gene-gender interaction was observed for the glutathione-S-transferase M1 (GSTM1) genotype. The GSTM1-null genotype was associated with a significantly higher median MN frequency in men, not in women. Statistical analysis did not reveal any association between the presence of the protective allele, pushing the pathway towards benzene detoxification, and MN frequency or S-PMA excretion. Even though there are some limitations in the study, our results indicate that policemen are exposed to higher levels of benzene than individuals spending most of the time indoors. This higher exposure may contribute to DNA damage, suggesting an increase health risk from traffic benzene emission. Finally, a more comprehensive study is warranted in order to better elucidate the involvement of EPHX1 genotypes combination in benzene genotoxicity.

Urinary biomarkers and low-level environmental benzene concentration: assessing occupational and general exposure.

The categories of urban workers undergoing prolonged exposure to gasoline due to vehicle emissions, evaporation and traffic fumes are considered occupationally exposed to benzene, even if at low concentrations. The aim of this study was to evaluate the specificity of unmetabolized benzene excreted in urine (UBz) and S-phenylmercapturic acid (SPMA) as biomarkers of exposure to very low levels of benzene, and to study the impact of putative individual confounders like smoking and alcohol habits, co-exposure to other toxicants and body mass index on the exposure assessment. Environmental and biological monitoring of exposure to benzene were performed in 114 Urban Policemen. The mean value of UBz in non-smokers was significantly lower than in either groups of light to moderate smokers and heavy smokers (0.24, 1.82 and 2.82 microg L(-1), respectively). On the contrary, SPMA values did not discriminate exposure resulting from smoking habits. Moreover, the concentration of UBz in non-smokers appears to be correlated with environmental benzene concentration (BenzA) (R(2)=0.13, beta=0.37, p=0.002). On the other hand, no significant correlation was found between SPMA concentration (corrected for creatinine excretion and log transformed, LogSPMA) and LogBenzA (R(2)=0.003, beta=0.05, p=0.6). Our findings reinforce previous research on the use of unmetabolized urinary benzene as a specific and sensitive biomarker of low-level exposure to benzene and confirm that smoking habits strongly influence the excretion of UBz.

Carpal tunnel syndrome and manual work: a longitudinal study.

OBJECTIVE: To assess risks associated with work-related biomechanical overloads in onset/course of carpal tunnel syndrome. METHODS: Work-groups with job tasks spanning different biomechanical exposures were evaluated at baseline in terms of American Conference of Governmental Industrial Hygienists hand-activity/peak force action limit and threshold limit values (TLV). Exposures of interest were "unacceptable" (hand-activity above TLV) and "borderline" (between action limit and TLV) overloads. Clinical/individual data were collected at baseline and 12 months. RESULTS: One-year incidence of "classic/possible" carpal tunnel syndrome symptoms as defined by consensus criteria was 7.3% (153 of 2092). "Unacceptable" overload was associated with a 3-fold increased risk of onset with respect to "acceptable" load. At ordered logistic regression analysis of symptom-status variations, increased risks were recorded for "unacceptable" and "borderline" overloads. CONCLUSIONS: Effectiveness of encouraging workplace adherence to the American Conference of Governmental Industrial Hygienists recommendations deserves investigation as a possible key to wide-scale prevention.

Relationship between repetitive work and the prevalence of carpal tunnel syndrome in part-time and full-time female supermarket cashiers: a quasi-experimental study.

OBJECTIVES: To investigate the prevalence of Carpal Tunnel Syndrome (CTS) in full-time and part-time supermarket cashiers exposed to a different weekly duration of biomechanical load. METHODS: All the 269 cashiers and 127 office workers were asked to participate. The protocol included ergonomic risk assessment, collection of personal and clinical data and bilateral electrodiagnostic study of the median nerve. CTS symptoms were defined as past and/or current nocturnal and/or diurnal numbness, tingling, burning or pain involving at least one of the first three fingers. Results were evaluated according to two case definitions based on current symptoms and on the combination of current symptoms and slowing of sensory conduction velocity from wrist to palm, respectively. Difference in proportions of CTS symptoms and cases was evaluated by the Pearson's chi-square (chi(2)) test, univariate and multivariate logistic regression analyses were performed to determine the impact of weekly exposure. RESULTS: The final female study population included 71 full-time cashiers, 155 part-time cashiers and 98 office workers. Ergonomic risk level was rated 5 for hand activity level and 4 for peak of force according to ACGIH. The intersection of the two values fell on the threshold limit value line, confirming the possible exposure to biomechanical risk factors for CTS. The prevalence of current CTS symptoms was higher among full-time (31.0%) than in part-time cashiers (19.3%) or controls (16.3%) (p = 0.055). A similar pattern was found for CTS past symptoms and cases. Univariate analysis showed that full-time cashiers had a 2.3 fold increased risk for CTS specific current symptoms than control subjects. A similar trend also emerged for CTS cases but was not significant (Odds ratios 1.23). Multivariate logistic regression analysis confirmed the increased risk for CTS current symptoms in full-time cashiers. CONCLUSIONS: Intensive manual work associated with inadequate recovery time might have generated an impairment of the median nerve at the wrist level proportionally increasing with duration of hand use. Our study can provide useful information both for ergonomic risk assessment and work organization.

Urban atmospheric pollution: personal exposure versus fixed monitoring station measurements.

We initiated the PETER (pedestrian environmental traffic pollutant exposure research) project to investigate pedestrians' exposure to traffic related atmospheric pollutants, based on data obtained with the collaboration of selected categories of pedestrian urban workers. We investigated relations between roadside personal exposure levels of volatile aromatic hydrocarbons (including benzene) and particulate matter <10 microm (PM10) among traffic police (n = 126) and parking wardens (n = 50) working in downtown Bologna, Italy. Data were collected from workshifts throughout four 1-week periods in different seasons of 2000-2001. For benzene and PM10, comparisons were made with measurements by fixed monitoring stations, and influence of localized traffic intensity and meteorological parameters was examined. Roadside personal exposure to benzene correlated more strongly with other volatile aromatic hydrocarbons (toluene, xylenes and ethylbenzene) than with PM10. Benzene and PM10 personal exposure levels were higher than fixed monitoring station values (both p<0.0001). At multivariate analysis, benzene and PM10 data from fixed monitoring stations both correlated with meteorological variables, and were also influenced by localized traffic intensity. Plausibly because of the downtown canyon-like streets, weather conditions (during a period of drought) only marginally affected benzene personal exposure, and moderately affected PM10 personal exposure. These findings reinforce the concept that urban atmospheric pollution data from fixed air monitoring stations cannot automatically be taken as indications of roadside exposures.

Efficacy of three face masks in preventing inhalation of airborne contaminants in dental practice.

BACKGROUND: Up-to-date studies are needed on the protection provided by face masks used by dentists. We assessed the relative filtering efficacy of two currently used surgical face masks (one a molded mask, the other a tie-on mask) and a certified personal particulate respirator, all made by a single manufacturer. METHODS: The authors sprayed bicarbonate particulate against a porcelain surface (representing the patient's mouth) and collected it via a mannequin head (representing the dentist's head) placed 40 centimeters away and a tube with two airflow rates (0.5 cubic meters per hour and 9 m3/hour). They calculated the dry residue weight. They performed three separate runs for each mask and three runs with no mask at the two airflow rates with and without aerosol. RESULTS: With no mask (control), the authors recorded significant weight gains at both airflow rates with and without vaporization. With vaporization, the three masks were associated with different dry residue weights (P < .03 with the Kruskal-Wallis test at both flow rates), the respirator propviding the lowest amount. The respirator provided an efficiency of 94 to 96 percent, compared with 90 to 92 percent and 85 to 86 percent for the molded and tie-on surgical masks, respectively. CONCLUSIONS: These data provide independent evidencependent evidence that a certified personalthat a certified personal respirator can be more effective than high quality surgical masks in dental settings. CLINICAL IMPLICATIONS: Dentists should be aware that a certified particulate respirator can provide them with superior filtering protection.

Relations between occupational, psychosocial and individual factors and three different categories of back disorder among supermarket workers.

OBJECTIVES: Up-to-date store-wide studies regarding low back pain (LBP) among supermarket/hypermarket workers are lacking. We investigated 12-month store-wide prevalence of different categories of LBP and possible associated biomechanical, individual/psychosocial risk factors across a large supermarket/hypermarket chain. METHODS: We performed a cross-sectional study of 3,702 subjects working in a group of small/medium-sized supermarkets (n=100) and large hypermarkets (n=7) belonging to a single chain in central-northern Italy applying established ergonomics/job-satisfaction policies. Data regarding the various departments were collected by a medical check-list, physical examination and questionnaire-all conducted by qualified physicians--and were analyzed in relation to a comprehensive biomechanical risk analysis. RESULTS: The overall 12-month prevalence of LBP in our sample (with a 82% response rate) was 34.5% (36.6% for females and 30.7% for males), with few differences being found between supermarkets and hypermarkets. Different types of LBP showed significant associations with stress-related psychosomatic symptoms, but not with job satisfaction (which was high). CONCLUSIONS: These encouraging data provide relevant information regarding workers operating in supermarkets/hypermarkets with an active commitment to ergonomic and job-satisfaction policies.

Occupational relevance of subclavian vein thrombosis in association with thoracic outlet syndrome.

OBJECTIVES: Primary subclavian vein thrombosis ("effort thrombosis") is not generally recognized as a work-related disorder, and more knowledge is required on the particular biomechanical risks. An extensive biomechanical risk analysis was performed for a possible work-related case. CASE REPORT: A hard-working 43-year-old race-course farrier received successful surgical treatment for subclavian vein thrombosis. No congenital abnormalities were apparent. At work, the farrier spent 75% of his time with his back bent (generally at > 70 degrees) with his right shoulder flexed and abducted, a position that thereby increased the pressure on the subclavian vein. High average (and peak) stress ratings for the neck and shoulder postures are accompanied by high levels of force and considerable repetitiveness. CONCLUSIONS: Taken together, these forms of biomechanical overload suggest that the leading cause of the subclavian thrombosis suffered by this farrier could have been occupational. Case-control studies on this neglected topic are needed to investigate possible associations between subclavian vein thrombosis and specific occupational activities.