Work-Related Risk Factors for Rotator Cuff Syndrome in a Prospective Study of Manufacturing and Healthcare Workers.

OBJECTIVE: This prospective study assessed the risk of developing rotator cuff syndrome (RCS) with separate or specific combinations of biomechanical exposures measures, controlling for individual confounders. BACKGROUND: Compared with other musculoskeletal disorders, rates of work-related shoulder musculoskeletal disorders have been declining more slowly. METHOD: We conducted up to 2 years of individual, annual assessments of covariates, exposures, and health outcomes for 393 U.S. manufacturing and healthcare workers without RCS at baseline. Task-level biomechanical exposures assessed exposure to forceful exertions (level, exertion rates, duty cycles), vibration, and upper arm postures (flexion, abduction). Hazard ratios (HRs) were calculated with Cox proportional hazard models. RESULTS: We observed 39 incident RCS cases in 694 person-years (incidence rate = 5.62 per 100 person-years). Adjusting for confounders, we found increased risk of incident RCS associated with forceful hand exertions per minute for three upper arm posture tertiles: flexion ≥45° (≥28.2% time, HR = 1.11, CI [1.01, 1.22]), abduction ≥30° (11.9-21.2%-time, HR = 1.18, CI [1.04, 1.34]), and abduction >60° (≥4.8% time, HR = 1.16, CI [1.04, 1.29]). We failed to observe statistically significant effects for other interactions or any separate measures of biomechanical exposure. CONCLUSION: This study highlights the importance of assessing combinations of exposure to forceful repetition and upper arm elevation when developing interventions for preventing RCS. APPLICATION: Based on these results, interventions that reduce exposure to forceful repetition (i.e., lower force levels and/or slower exertion rates) may reduce the risk of RCS, especially when upper arm elevation cannot be avoided.

Synthetic Cannabinoid and Mitragynine Exposure of Law Enforcement Agents During the Raid of an Illegal Laboratory - Nevada, 2014.

Synthetic cannabinoids (SCs), commonly known by the street name "Spice," are designer drugs of abuse that mimic the psychoactive effects of marijuana. Intentional SC use has resulted in multiple toxicities (1,2), but little is known about occupational SC exposure. After a federal agency's law enforcement personnel in Nevada reported irritability and feeling "high" after raiding illegal SC laboratories and processing seized SCs, a request for a health hazard evaluation was made by the agency to CDC's National Institute for Occupational Safety and Health (NIOSH) in 2014 to evaluate agents' occupational SC exposures. After making the request for a health hazard evaluation, federal agents conducted a raid of an illegal SC laboratory, with assistance from local law enforcement and Drug Enforcement Administration (DEA) personnel and with NIOSH investigators observing from a distance. After the raid, agents collected and processed material evidence. NIOSH investigators tested agents' urine for SC levels before and after the raid and measured SCs in the air and on surfaces after the raid. DEA determined that AB-PINACA (an SC compound) and mitragynine (a plant material with opium-like effects, also known as "kratom") were present in the illegal laboratory. AB-PINACA, its metabolites, and mitragynine were not detected in agents' urine before the raid; however, one or more of these substances was found in the urine of six of nine agents after the raid and processing of the SC evidence. AB-PINACA was detected in one surface wipe sample from the SC laboratory; none was detected in the air in the laboratory or in the offices of the law enforcement agency where the materials were processed after the raid. No policies were in place regarding work practices and use of personal protective equipment (PPE) during raids and evidence processing. To protect agents from SC exposures, NIOSH recommended that the agency require agents to wear a minimum level of PPE (e.g., protective gloves and disposable clothing) and undergo training in PPE and in handling and storing of contaminated evidence from SC laboratory raids. Showers and locker rooms also need to be provided so that agents can reduce contamination and prevent take-home exposure.

Recommendations to Improve Employee Thermal Comfort When Working in 40°F Refrigerated Cold Rooms.

Cold rooms are commonly used for food storage and preparation, and are usually kept around 40°F following food safety guidelines. Some food preparation employees may spend 8 or more hours inside cold rooms. These employees may not be aware of the risks associated with mildly cold temperatures, dampness, and limited ventilation. We performed an evaluation of cold rooms at an airline catering facility because of concerns with exposure to cold temperatures. We spoke with and observed employees in two cold rooms, reviewed daily temperature logs, evaluated employee's physical activity, work/rest schedule, and protective clothing. We measured temperature, percent relative humidity, and air velocities at different work stations inside the cold rooms. We concluded that thermal comfort concerns perceived by cold room employees may have been the result of air drafts at their workstations, insufficient use of personal protective equipment due to dexterity concerns, work practices, and lack of knowledge about good health and safety practices in cold rooms. These moderately cold work conditions with low air velocities are not well covered in current occupational health and safety guidelines, and wind chill calculations do not apply. We provide practical recommendations to improve thermal comfort of cold room employees. Engineering control recommendations include the redesigning of air deflectors and installing of suspended baffles. Administrative controls include the changing out of wet clothing, providing hand warmers outside of cold rooms, and educating employees on cold stress. We also recommended providing more options on personal protective equipment. However, there is a need for guidelines and educational materials tailored to employees in moderately cold environments to improve thermal comfort and minimize health and safety problems.

A prospective study of carpal tunnel syndrome: workplace and individual risk factors.

OBJECTIVES: To quantify the risk for carpal tunnel syndrome (CTS) from workplace physical factors, particularly hand activity level and forceful exertion, while taking into account individual factors including age, gender, body mass index (BMI), and pre-existing medical conditions. METHODS: Three healthcare and manufacturing workplaces were selected for inclusion on the basis of range of exposure to hand activity level and forceful exertion represented by their jobs. Each study participant's job tasks were observed and evaluated onsite and videotaped for further analysis, including frequency and duration of exertion and postural deviation. Individual health assessment entailed electrodiagnostic testing of median and ulnar nerves, physical examination and questionnaires at baseline with annual follow-up for 2 years. RESULTS: The incidence of dominant hand CTS during the study was 5.11 per 100 person-years (29 cases). Adjusted HRs for dominant hand CTS were as follows: working with forceful exertion ≥ 20% but <60% of the time: 2.83 (1.18, 6.79) and ≥ 60% of the time vs <20%: 19.57 (5.96, 64.24), BMI ≥ 30 kg/m(2) (obesity): 3.19 (1.28, 7.98). The American Conference for Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) for hand activity level also predicted CTS, HR=1.40 (1.11, 1.78) for each unit increase in the TLV ratio, controlling for obesity and job strain. CONCLUSIONS: Workplace and individual risk factors both contribute to the risk for CTS. Time spent in forceful exertion can be a greater risk for CTS than obesity if the job exposure is high. Preventive workplace efforts should target forceful exertions.

Workplace and individual risk factors for carpal tunnel syndrome.

OBJECTIVES: To quantify the relationship between workplace physical factors, particularly hand activity level (HAL) and forceful exertion and carpal tunnel syndrome (CTS), while taking into account individual factors. To compare quantitative exposure assessment measures with more practical ratings-based measures. METHODS: In a group of healthcare and manufacturing workers, each study participant's job tasks were evaluated for HAL, forceful exertion and other physical stressors and videotaped for further analysis, including frequency and duration of exertion and postural deviation. Electrodiagnostic testing of median and ulnar nerves and questionnaires were administered to all participants. A CTS case required median mononeuropathy and symptoms on hand diagrams in fingers 1-3. Multiple logistic regression models were used to analyse associations between job and individual factors and CTS. RESULTS: Of 477 workers studied, 57 (11.9%) were dominant hand CTS cases. Peak force ≥70% maximum voluntary contraction versus <20% maximum voluntary contraction resulted in an OR of 2.74 (1.32-5.68) for CTS. Among those with a body mass index ≥30, the OR for ≥15 exertions per minute was 3.35 (1.14-9.87). Peak worker ratings of perceived exertion increased the odds for CTS by 1.14 (1.01-1.29) for each unit increase on the 10-point scale. The odds for CTS increased by 1.38 (1.05-1.81) for each unit increase on the HAL 10-point scale among men, but not women. Combined force and HAL values above the ACGIH TLV for HAL resulted in an OR of 2.96 (1.51-5.80) for CTS. DISCUSSION/CONCLUSIONS: Quantitative and ratings-based job exposure measures were each associated with CTS. Obesity increased the association between frequency of exertion and CTS.

A comparison of assessment methods of hand activity and force for use in calculating the ACGIH(R) hand activity level (HAL) TLV(R).

This article compares several methods that were used for determining hand activity level and force in a large prospective ergonomics study. The first goal of this analysis was to determine the degree of correlation between hand activity/ force ratings using different assessment methods. The second goal was to determine if the hand activity/force methods were functionally equivalent for the purpose of calculating the ACGIH(R) hand activity level (HAL) threshold limit value (TLV(R)). A final goal was to investigate reasons for potential differences between methods. More than 700 task analyses were conducted on 484 workers at three study locations. Hand activity was assessed by two methods, including a trained observer on site using a 10-point visual analog scale for hand activity level and by offsite video analysis of the same task to calculate the frequency of exertions and the work/recovery ratio. Hand force was assessed by two on-site methods: ratings of perceived exertion (RPE) using a modified Borg CR-10 scale by a trained observer and RPE by the worker performing the task. The two methods for assessing hand activity level were correlated (Spearman rank = 0.49) and produced main TLV result categories (below Action Limit, Action Limit, TLV) with percent of exact agreement ranging from 71 to 91% and weighted Kappa ranging from 0.61 to 0.75. The two RPE methods for assessing hand force were correlated (Spearman rank ranging from 0.47 to 0.69) and produced TLVs with percent of exact agreement ranging from 64 to 83% and weighted Kappa ranging from 0.52 to 0.62. Differences between methods may be explained by a number of task and subject variables that were significantly associated with higher levels of hand activity and force. In summary, this study found substantial agreement between two methods for assessing hand activity level and moderate agreement between two methods for assessing hand force.

Comprehensive Analysis of Aspergillus nidulans PKA Phosphorylome Identifies a Novel Mode of CreA Regulation.

In filamentous fungi, an important kinase responsible for adaptation to changes in available nutrients is cyclic AMP (cAMP)-dependent protein kinase (protein kinase A [PKA]). This kinase has been well characterized at a molecular level, but its systemic action and direct/indirect targets are generally not well understood in filamentous fungi. In this work, we used a pkaA deletion strain (ΔpkaA) to identify Aspergillus nidulans proteins for which phosphorylation is dependent (either directly or indirectly) on PKA. A combination of phosphoproteomic and transcriptomic analyses revealed both direct and indirect targets of PKA and provided a global perspective on its function. One of these targets was the transcription factor CreA, the main repressor responsible for carbon catabolite repression (CCR). In the ΔpkaA strain, we identified a previously unreported phosphosite in CreA, S319, which (based on motif analysis) appears to be a direct target of Stk22 kinase (AN5728). Upon replacement of CreA S319 with an alanine (i.e., phosphonull mutant), the dynamics of CreA import to the nucleus are affected. Collectively, this work provides a global overview of PKA function while also providing novel insight regarding significance of a specific PKA-mediated phosphorylation event.IMPORTANCE The cyclic AMP (cAMP)-dependent protein kinase A (PKA) signaling pathway is well conserved across eukaryotes, and previous work has shown that it plays an important role in regulating development, growth, and virulence in a number of fungi. PKA is activated in response to extracellular nutrients and acts to regulate metabolism and growth. While a number of components in the PKA pathway have been defined in filamentous fungi, current understanding does not provide a global perspective on PKA function. Thus, this work is significant in that it comprehensively identifies proteins and functional pathways regulated by PKA in a model filamentous fungus. This information enhances our understanding of PKA action and may provide information on how to manipulate it for specific purposes.

Carpal tunnel syndrome prevalence: an evaluation of workers at a raw poultry processing plant.

OBJECTIVES: Evaluate the prevalence of carpal tunnel syndrome (CTS) among workers at a raw poultry processing plant and categorize jobs on the basis of hand activity and force. METHODS: A cross-sectional survey among 191 workers assessed CTS defined by self-reported CTS symptoms, a hand symptom diagram, and measurements of nerve conduction parameters. We categorized jobs based on American Conference of Governmental Industrial Hygienists' (ACGIH®) limits for hand activity and force, and examined the relationships with CTS occurrence. RESULTS: A total of 64 workers (34%) had CTS after adjusting for non-occupational factors. Overall, 81% of jobs were above the ACGIH action limit; 59% were above the ACGIH threshold limit value®. CTS prevalence did not differ significantly between exposure groups (PR = 0.82, p = 0.35). CONCLUSIONS: These findings suggest that poultry processing jobs continue to be hazardous with workers at risk for CTS. Recommendations for the study population were provided to reduce exposure and CTS risk among workers.

Prevalence of carpal tunnel syndrome among employees at a poultry processing plant.

OBJECTIVE: To determine prevalence of carpal tunnel syndrome (CTS) among poultry processing employees while taking into account non-occupational factors and assess any association between CTS prevalence and exposure groups. METHODS: Performed a cross-sectional survey to assess CTS (n = 318). A CTS case was defined as an employee with self-reported CTS symptoms, an abnormal hand symptom diagram, and an abnormal nerve conduction study (NCS). Log-binomial regression was used to estimate prevalence ratios. RESULTS: Three hundred and one participants had sufficient symptom information or NCS data to be classified. 126 (42%) of 301 participants had evidence of CTS. In the adjusted analysis, the highest exposure group had CTS prevalence that was significantly higher than that for the lower exposure group [PR: 1.61; 95% CI = (1.20, 2.17)]. CONCLUSIONS: Increasing levels of hand activity and force were associated with increased CTS prevalence among participants. Recommendations were provided to reduce exposure to these risk factors.