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Low temperatures pose a significant yet underrecognized occupational health risk, particularly for outdoor workers with climate-sensitive medical conditions such as diabetes, cardiovascular disease, and respiratory disorders. While cold exposure is often associated with Arctic and high-altitude regions, even temperate and warmer climates experience severe winter temperature drops, placing a broad spectrum of outdoor workers at risk. Despite extensive research highlighting the adverse health effects of cold stress and its contribution to global mortality rates, occupational health and safety (OHS) guidelines remain disproportionately focused on heat-related risks, neglecting the unique vulnerabilities of workers exposed to extreme cold. This paper critically examines the gaps in current OHS policies and regulations regarding cold exposure, emphasizing the urgent need for evidence-based guidelines that specifically address the needs of outdoor workers with preexisting health conditions. By integrating medical, environmental, and occupational safety perspectives, we propose a framework for comprehensive protective measures, including improved risk assessment protocols, workplace adaptations, and regulatory interventions. Addressing this oversight is essential not only for safeguarding workers’ health but also for promoting sustainable labor practices and enhancing resilience in industries where cold exposure is a persistent threat. Establishing clear, targeted guidelines will be a crucial step toward mitigating cold-related occupational hazards and fostering a healthier global workforce.

OBJECTIVE: To evaluate the association between exposure to occupational biomechanical factors and the incidence of surgically treated osteoarthritis (OA) treated with arthroplasty in the hip and knee among male construction workers.

DESIGN: Longitudinal register-based cohort study.

PARTICIPANTS AND SETTING: Male construction workers (n=291 062) who participated in a national Swedish occupational health examination programme between 1971 and 1993, delivered through multiple primary-level nationwide occupational health centres.

PRIMARY AND SECONDARY OUTCOME MEASURES: Hip and knee arthroplasties performed due to OA from 1987 to 2019 were identified through linkage with the Swedish National Patient Register. Data on age, smoking habits, body mass index, job title and self-reported biomechanical exposures were collected during the health examinations. Occupational biomechanical workload was assessed using eight factors from a job-exposure matrix. Poisson regression was applied to estimate adjusted incidence rate ratios (IRRs) associated with each type of occupational biomechanical exposure.

RESULTS: The study included 10 336 cases of hip arthroplasties and 8926 cases of knee arthroplasties. All studied biomechanical risk factors were associated with an increased risk of knee OA requiring arthroplasty, especially for individuals exposed to static work in non-neutral lumbar postures (IRR 1.38, 95% CI 1.16 to 1.65) and those with a high frequency of kneeling (IRR 1.27, 95% CI 1.12 to 1.45). In contrast, only a few biomechanical factors were associated with an increased risk of hip OA requiring arthroplasty. Similar results were observed when alternative exposure measures, such as occupational group and self-reported exposure assessments, were employed.

CONCLUSIONS: Occupational workload was associated with an increased risk of knee arthroplasty due to OA, whereas the association for hip arthroplasty remains unclear.

Objective: To measure and determine the occupational cardiovascular workload and cardiovascular fitness among older employees (50 +) in four physically demanding occupational groups.

Methods: Health investigations, including aerobic capacity, were performed on 120 construction and kitchen workers, cleaners, and assistant nurses. Cardiovascular load was assessed over three working days using heart rate (HR) measurements. Data was processed for average loads (HR and Relative HR reserve (%HRR)) and measures describing variations in loads, such as time spent in different heart rate intensities.

Results: Participants’ mean age was 57 (SD 4.1) years, and 63% of the participants were female. The mean %HRR over occupational groups was 24.9% (SD 6.8). Of the participants, 43% had an average cardiovascular load above 24.5%HRR and 11% over 33%HRR. Depending on the work sector, 22–37% of the worktime was spent in intensities over 30%HRR, and 2–4% was spent in cardiovascular intensities over 50%HRR. The average VO2max was 33.2 (SD 8.2) ml/kg/min for all, for men 39.0 (SD 7.0), and for women 29.8 (SD 6.9).

Conclusion: We found a high mean cardiovascular load at work among the senior workers in all four work sectors, but low proportions of the worktime were spent in high intensity levels. Despite a high mean cardiovascular load at work, a high proportion of the workers had low cardiovascular fitness. Given the possible negative effects of occupational physical activity and to meet future demographic challenges, future interventions should aim to reduce physical loads and increase physical fitness in the workforce.

The main aim of this study was to describe the degree of cold exposure and occupational physical activity within three different outdoor occupational groups in northern Sweden using both technical measurements and self-reported survey items. The cold exposure and physical activity of workers in preschool, park and maintenance and power grid sectors (N = 133) were examined using a digital survey, temperature loggers and thigh-worn accelerometers. In the survey, 33% of workers indicated that they often or always felt cold at work, and 39% reported that they had inadequate knowledge about cold weather protection. The median (interquartile range, IQR) duration of working at ambient temperatures below 10°C was 131 (157) minutes. The physical activity while working outdoors was composed of sitting (20%), standing (54%) and walking (26%). About one-third of the participants reported that they often or always felt cold at their workplace, with an average of more than two hours spent outside at temperatures below 10°C. Possible remedies include increasing physical activity and improving thermal insulation of the clothing.

Background: There is a need for efficient screening for hand-arm vibration injury.

Aims: To evaluate the diagnostic test performance of screening questions for neurosensory injury in relation to clinical testing among hand-arm vibration (HAV)-exposed workers.

Methods: HAV-exposed subjects responded to a screening survey on subjective perception of touch, warmth, cold, and vibration, as well as grip strength and manual dexterity. Perception of monofilament, two-point discrimination, temperature rollers, and tuning fork was tested on the index and little fingers of both hands, while grip strength was tested using a hydraulic dynamometer. Diagnostic test performance characteristics were calculated based on crosstabulation of survey responses and outcomes of clinical testing.

Results: Our study recruited 225 subjects with exposure durations between one and 43 years. The sensitivity and specificity for the question about impaired ability to feel touch compared with monofilament was 65% and 71%; impaired ability to feel heat compared with temperature rollers 50% and 75%; impaired ability to feel cold compared with temperature rollers 39% and 77%; impaired ability to feel vibration compared with tuning fork 49% and 84%; reduced grip strength compared with hydraulic dynamometer 83% and 58%; and difficulty fastening buttons compared with two-point discrimination 40% and 76%, respectively.

Conclusions: The diagnostic test performance of the currently used screening survey for neurosensory injury among HAV-exposed workers needs to be improved. Future development should focus on establishing more specific questions, balanced response alternatives, and a more sophisticated interpretation of the responses, possibly using an index made up of several screening questions.

Objective: Workers exposed to hand-arm vibration (HAV) commonly experience discomfort in their hands when cold. There is a lack of diagnostic tests for such abnormal cold sensitivity. The main aim of our study was to evaluate the results of cold stress testing in relation to self-reported cold sensitivity among HAV-exposed workers.

Methods: We recruited 225 workers exposed to HAV who responded to a written screening question about cold sensitivity. Cold stress testing was conducted, where the right hand was immersed in 3.0 °C circulating water for up to 60 seconds. The tolerance time for immersion as well as continuous pain ratings on a digital visual analog scale (ranging from 0 to 100 millimeters) were recorded.

Results: The study sample consisted of 208 males (92.4 %) and 17 females, with a mean (SD) age of 40.6 (13.7) years. Among the 190 workers that completed cold stress testing, the mean (SD) tolerance time was 43.7 (16.4) seconds, mean (SD) maximum pain rating 69.8 (27.6) millimeters, and mean (SD) time to maximum pain 38.7 (15.9) seconds. Cold sensitivity was reported by 54 workers (24.1 %). Cold sensitivity was not statistically significantly associated with tolerance time or maximum pain rating, but symptomatic workers had a shorter time to maximum pain (p = 0.018).

Conclusions: Workers who reported cold sensitivity experienced a more rapid increase in cold-related pain, had a tendency towards shorter tolerance time but did not differ in maximum pain ratings. Further studies are needed to determine how to effectively investigate cold sensitivity among HAV-exposed workers.

There is an association between local cold injuries and Raynaud’s phenomenon (RP) in the scientific literature, but the time relation and anatomical correlation have not been established. During military training in an Arctic setting, a previously healthy man in his early twenties sustained a freezing cold injury affecting mainly his right index finger. He subsequently developed Raynaud’s phenomenon limited to only the part of the index finger that was originally affected by the cold injury. Medical investigation also revealed findings suggestive of subclinical peripheral neuropathy. This case demonstrates that Raynaud’s phenomenon can develop secondary to local cold injury affecting the hand. It also suggests that cold exposure could be related to peripheral neuropathy.

Diisocyanates are a group of chemicals used in many different applications, such as plastics, foams, coatings, adhesives, and sealants. Prolonged occupational exposure can result in severe asthma. This case report presents a non-smoking male without any previous respiratory disease, where severe obstructive airway symptoms developed during a single event with high airborne exposure to polyurethane foam containing methylene diphenyl diisocyanate during the coating of a large vehicle. The subject was subsequently diagnosed with occupational asthma based on a significant variability in a two-week peak expiratory flow curve and a positive metacholine challenge. Despite aborted exposure and optimized asthma treatment, the subject continued to experience debilitating airway symptoms. This case report demonstrates that severe asthma can develop following a single exposure to polyurethane foam containing methylene diphenyl diisocyanate, underscoring the importance of preventive measures in workplaces where such chemicals are used.

Objectives: To prospectively determine the association between occupational biomechanical exposures and the incidence of surgically treated carpal tunnel syndrome (CTS) in Swedish male construction workers.

Methods: A cohort of 203 866 Swedish male construction workers who participated in a national occupational health surveillance programme between 1971 and 1993 were followed for CTS surgery between 2001 and 2019. Age, height, weight, smoking status and construction trade were obtained from programme records. CTS surgery cases were defined using the diagnostic code for CTS and surgical procedure code for peripheral median nerve decompression in the Swedish National Patient Register. Biomechanical exposure estimates were assigned by trade from a job-exposure matrix. The relative risk (RR) of CTS surgery for each biomechanical exposure was assessed with multivariable negative binomial regression modelling.

Results: The study included 3851 cases and the total incidence rate of CTS surgery was 137.6 cases per 100 000 person-years. Associations were found for upper extremity load (RR 2.6; 95% CI 2.2 to 3.0), repetitive wrist flexion and extension (RR 2.6; 95% CI 2.2 to 3.0), full wrist extension (RR 2.3; 95% CI 1.9 to 2.6), power grip (RR 2.5; 95% CI 2.2 to 2.9), pinch grip (RR 2.0; 95% CI 1.7 to 2.4), handheld tool use (RR 2.3; 95% CI 2.0 to 2.7) and hand-arm vibration exposure (RR 2.3; 95% CI 1.9 to 2.7).

Conclusions: Occupational upper extremity load and postural exposures were associated with increased risk for surgical treatment for CTS in this large construction worker cohort. Preventive actions and consideration of occupation on assessment are warranted.

Background: Contrary to leisure-time physical activity, high levels of occupational physical activity (OPA) have been linked to cardiovascular disease and mortality. Many occupations in the construction industry are known to have high levels of OPA.Aims This study investigated OPA and stroke mortality risk among 299 382 Swedish male construction workers.

Methods: OPA was derived from job titles and categorized as low, medium or high, and stroke mortality was ascertained via the Swedish National Cause of Death Register. The average follow-up was 24 years resulting in a total of 6.9 million person-years, during which 4606 participants died from stroke. Relative risks were estimated with robust Poisson regressions and adjusted for age, calendar year, body mass index and smoking.

Results: The relative risk for overall stroke mortality was higher in the medium and high OPA groups compared to the low OPA group [1.15 (1.04, 1.27) and 1.13 (1.04, 1.23), respectively], with no clear dose-response association. Age-stratified analyses showed that higher OPA increased stroke mortality risk in participants between 70 and 89 years. Participants with high versus low OPA had a higher risk of ischaemic stroke mortality [1.15 (1.01, 1.31)].

Conclusions: Construction workers with high OPA have a slight increase in overall stroke mortality, mainly after retirement. Contrary to leisure-time physical activity, high levels of occupational physical activity have been linked to an increased risk of cardiovascular disease and mortality. Construction workers in this study with medium and high occupational physical activity had higher stroke mortality than those with low occupational physical activity. However, there was no difference in stroke mortality between those with high and medium occupational physical activity.