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OBJECTIVES: The study investigated the association between occupational biomechanical risk factors and the occurrence of thumb carpometacarpal joint osteoarthritis (CMC1 OA) in construction workers.

METHODS: Male construction workers (n=237 525), participating in a Swedish occupational surveillance programme between 1971 and 1993, were followed between 1997 and 2019. CMC1 OA diagnoses were identified through linkage with national medical registries. Job title, smoking status, height, weight and age were collected from the surveillance programme. A job exposure matrix (JEM) was developed with exposure estimates on biomechanical risk factors for each occupational group. Relative risk (RR) of CMC1 OA diagnosis was calculated using a Poisson regression model.

RESULTS: There was an increased risk of CMC1 OA for all biomechanical risk factors (RR range 1.3-1.5). Exposure-response patterns were seen for repetitive wrist flexion and extension (low: RR 1.30 (95% CI 1.07 to 1.59), moderate: 1.32 (95% CI 1.07 to 1.62), high: 1.45 (95% CI 1.19 to 1.75)), wrist extension (low: 1.31 (95% CI 1.09 to 1.59), moderate: 1.41 (95% CI 1.17 to 1.70) and heavy lifting (low: 1.13 (95% CI 0.92 to 1.38), moderate: 1.45 (95% CI 1.18 to 1.77), high: 1.50 (95% CI 1.24 to 1.82). Electricians (1.29 (95% CI 1.03 to 1.89)), concrete workers (1.31 (95% CI 1.02 to 1.67)), plumbers (1.37 (95% CI 1.07 to 1.76)), sheet-metal workers (1.58 (95% CI 1.18 to 2.10)), wood workers (1.66 (95% CI 1.36 to 2.03)), repairers (1.75 (95% CI 1.06 to 2.90)) and glass workers (2.21 (95% CI 1.42 to 3.44) had an increased risk of CMC1 OA compared with the reference group.

CONCLUSION: Wrist movements and hand loading were associated with CMC1 OA.

Workers who use handheld vibrating machines such as grinders, hammers and chainsaws expose themselves to hand-arm vibration (HAV). Exposure to HAV may cause injuries to both the neurological and the vascular system. The occupational health services (OHS) in Sweden use a formal guideline for secondary prevention focusing on early detection of vibration-related injuries. The guide includes several screening tools, such as a screening questionnaire, clinical examinations, and laboratory tests. There are no studies, to our knowledge, on the diagnostic value of the separate items on symptoms in the screening questionnaire in relation to the laboratory tests or the clinical examinations performed during a medical examination among patients exposed to HAV. Furthermore, the recently presented ISO standard for HAV measurements (ISO/TR 18,750) has only been tested for vascular injuries and not neurological injuries. This research roadmap aims to evaluate separate items in a screening questionnaire on neurological symptoms in relation to laboratory and clinical tests among HAV exposed workers in the Arctic region of Northern Sweden. It also covers a comparison of the dose-response of the current ISO 5349-1 measurement standard and the new suggested standard ISO/TR 18,750 with the neurosensory outcomes. This manuscript describes the study rationale, design, methods, and significance.

Det övergripande syftet med denna narrativa kunskapsöversikt var att beskriva hur hälsorisker förknippade med arbete i kyla påverkas av ålder och sjukdom. En systematisk litteratursökning genomfördes i Medline, Embase och World of Science för perioden 1980–2023 med tre huvudsakliga block: kall miljö, arbete och riskbedömning. Sökningen resulterade i 6965 artiklar varav 277 granskades i sin helhet och 13 av dessa inkluderades i översikten över riskbedömning och riskhantering av arbete i kyla. I tillägg till den systematiska litteratursökningen gjordes en fri sökning av vetenskaplig litteratur med fokus på åldrande och sjukdomar samt en genomgång av andra kunskapskällor.

Den systematiska litteratursökningen visade att det finns etablerade metoder för strukturerad riskbedömning av arbete i kyla även om arbetsmiljöerna kan se väldigt olika ut. De flesta rapporterar att både ålder och sjukdom kan påverka sårbarheten för kyla.

I den fria sökningen återfanns små experimentella studier som visar att sårbarheten för kyla ökar med åldern. Denna sårbarhet kan betingas av förändringar i värmeproduktion, isolerande förmåga, perifer vasoreglering samt temperaturdiskriminering.

Vad gäller hjärt-kärlsjukdom fanns vetenskapligt underlag för att exponering för kyla leder till högre blodtryck, både hos dem med och utan läkemedelsbehandling mot hypertoni. Personer med befintlig hjärt-kärlsjukdom uppvisar en lägre fysisk arbetsförmåga och en ökad sannolikhet att insjukna i akuta ischemiska hjärthändelser och arytmier vid exponering för kyla. Exponering för kyla förefaller även öka sannolikheten för stroke.

För obstruktiv lungsjukdom visade litteraturen att exponering för kyla kan öka symptombördan hos personer med astma eller kroniskt obstruktiv lungsjukdom. Särskilt exponering av ansiktet för kyla kan framkalla obstruktiva luftvägsbesvär. Det finns även vissa hållpunkter för att tidigare friska personer som exponeras för kyla kan insjukna i obstruktiva luftvägsbesvär.

Vad gäller diabetes fanns beskrivet att exponering för kyla kan leda till försämrad metabol kontroll, ökad risk för hypoglykemier, ökad benägenhet till hypotermi samt möjligen även ökad risk för lokala kylskador och onormal köldkänslighet.

För rörelseapparaten fanns studier som visade att arbete i kyla ökar sannolikheten att rapportera muskuloskeletala smärttillstånd. Arbete i kyla kan också öka sannolikheten att rapportera nervrelaterade besvär som ischias och karpaltunnelsyndrom.

Sammanfattningsvis finns vetenskapligt underlag för att arbete i kyla kan vara förknippat med ökade hälsorisker för personer i högre arbetsför ålder och med befintliga sjukdomar. Hur arbete i kyla påverkar arbetsförmågan och den fortsatta prognosen är mindre tydligt. I Sverige saknas enhetlig reglering av arbete i kyla utomhus. Det finns metoder för riskbedömning och riskhantering av arbete i kyla samt förslag på praktiska tillvägagångssätt för arbetare, arbetsgivare och företagshälsor. Bland identifierade kunskapsluckor kan nämnas hälsoeffekter av långvarig men låggradig yrkesexponering för kyla, könsskillnader, acklimatisering, exponerings-responssamband samt samverkande effekter av kyla tillsammans med andra exponeringar.

Hand-arm vibration is a common occupational exposure that causes neurological impairment, myalgia, and vibration-induced Raynaud’s phenomena or vibration white fingers (VWF). The pathological mechanism is largely unknown, though several mechanisms have been proposed, involving both immunological vascular damage and defective neural responses. The aim of this study was to test whether the substances interleukin-33 (IL-33), macrophage-derived chemokine (MDC), interleukin-10 (IL-10), endothelin-1 (ET-1), C-C motif chemokine ligand 20 (CCL20), calcitonin, and thromboxane (TXA2) changed before and after occupational hand-arm vibration exposure. 38 full-time shift workers exposed to hand-arm vibration were recruited. All the participants underwent medical examinations regarding symptoms of Raynaud’s phenomena. In 29 of the participants, the concentration of IL-33, MDC, IL-10, ET-1, CCL20, calcitonin, and TXA2 was measured before and after a workday. There was a significant increase in ET-1 and calcitonin concentration and a decrease in the CCL20 concentration after the work shift in all participants. In the group suffering from VWF, but not in the non-VWF group, MDC was statistically significantly lower before the work shift (p =.023). The VWF group also showed a significant increase in MDC after the work shift. Exposure to occupational hand-arm vibration is associated with changes in ET-1, calcitonin, and MDC concentration in subjects suffering from vibration white fingers, suggesting a role of these biomarkers in the pathophysiology of this condition.

Objectives: This study aimed to evaluate the influence of individual characteristics (sex, age, body mass index [BMI] and smoking habits) on the tolerance time, pain ratings and rewarming time of hand cold stress testing (CST).

Methods: We included 153 subjects (63% men) working in a Swedish open-pit mine (participation rate 41%). The right hand was immersed in 3 °C circulating water for up to 45 s. Pain ratings were registered every fifth second using a visual analog scale.

Results: The tolerance time (mean ± standard deviation) was 35 ± 12 s for men and 29 ± 14 s for women (p = 0.007). The youngest age group (18–29 years) had the longest tolerance time, while the oldest group (54–65 years) had the shortest (p = 0.005). Women had significantly higher pain ratings than men after 5, 10 and 25 s. The group with the highest BMI had the shortest rewarming time (p < 0.001).

Conclusions: Age and sex influenced the tolerance time of hand CST, while only sex affected the pain ratings and BMI the rewarming time. When performing CST in future studies, these parameters should be considered.

The primary aim of this study was to determine if occupational exposure to whole-body vibration (WBV) was associated with reporting neck pain. A cross-sectional study was conducted on a sample of the general population living in northern Sweden, aged 24-76 years. Data was retrieved through a digital survey that collected subjectively reported information on exposure to WBV and biomechanical exposures as well as neck pain. The study included 5,017 participants (response rate 44%). Neck pain was reported by 269 men (11.8%) and 536 women (20.2%). There was a statistically significant association between reporting occupational exposure to WBV half the time or more (adjusted OR 1.91; 95% CI 1.22-3.00) and reporting neck pain. In gender-stratified analyses, the same pattern was observed in men, while there were too few women to determine any association. We conclude that occupational exposure to whole-body vibration was associated with neck pain in men.

The literature on Raynaud’s phenomenon (RP) in the feet is scarce, especially in the occupational setting. The primary aim of our study was to investigate the occurrence of RP in the feet of miners. As part of the MineHealth project, written surveys and clinical examinations were completed by 260 Arctic open-pit miners working in northern Sweden and Norway (participation rate 53.6%). Data on RP were collected using standardised colour charts and questionnaire items. Clinical examination included assessing the perception of vibration and pain in both feet. There were eight women and three men who reported RP in the feet. Four also had RP in their hands but none acknowledged any first-degree relatives with the condition. Nine reported exposure to foot-transmitted vibration and one to hand-arm vibration. Seven showed signs of neurosensory injury in the feet. To conclude, the occurrence of RP in the feet of miners was 4.4%. Most cases with RP in the feet did not report the condition in the hands and were exposed to vibration transmitted directly to the feet. There were no reports of a hereditary component. Most cases with RP in the feet also had clinical findings suggestive of peripheral neuropathy in the feet.

Arctic miners face significant risks from diesel exhaust and dust exposure, potentially leading to adverse respiratory health. Employers must limit harmful exposures, using personal protective equipment (PPE) as a last line of defense. This study explored the association between reported respiratory exposure and symptoms, and PPE training and usage. Data from the MineHealth study (2012–2014) included a total of 453 Arctic open pit miners in Norway, Sweden, and Finland. Participants answered questions on exposure to dust and diesel exhaust, respiratory symptoms, and PPE use, in addition to age, gender, BMI, smoking, and self-rated health. Estimated exposure to dust was common, reported by 91%, 80%, and 82% and that of diesel exhaust by 84%, 43%, and 47% of workers in Sweden, Finland, and Norway, respectively. Reported dust exposure was significantly related to respiratory symptoms (OR 2.2, 95% CI 1.3–3.7), diesel exposure increased the occurrence of wheezing (OR 2.6, 95% CI 1.3–5.4). PPE use varied between the studied mines. Non-use was common and related to reduced visibility, wetness, skin irritation and fogging of the respiratory PPE. Future research should employ more precise exposure assessment, respiratory function as well as explore the reasons behind the non-compliance of PPE use.

Introduction: Colloidal silver ingestion as an alternative medicine treatment is becoming more common. This case report describes a patient with potential silver poisoning and severe anemia.

Case description: A woman in her late sixties was transported to the emergency department because of progressive fatigue and nausea. She had been drinking 150 µg of colloidal silver daily for two to three weeks. Blood sampling revealed severe anemia (red blood cell count 48 g/L) and a whole-blood silver concentration of 20 µg/L. Liver function tests were abnormal and there were signs of incipient heart failure with increased pro-brain natriuretic peptide, troponin T, as well as pleural effusion. She was stabilized with blood transfusion and symptomatic treatment, to be discharged from the hospital after ten days. The patient improved over the following six weeks and the whole-blood silver concentration decreased to 3.3 µg/L after about three months.

Conclusions: The case demonstrates the potential effects of silver intake on the hematopoietic, hepatic, and cardiovascular systems. This highlights the possible risks associated with emerging alternative medicine therapies.

Vibration exposure from handheld tools can affect the hands with neurological symptoms and vibration-induced Raynaud's phenomenon (VRP). The underlying pathophysiological mechanisms are not fully known, however, changes in the composition of blood parameters may contribute to VRP with an increase in blood viscosity and inflammatory response. The aim of this study was to examine the effect on blood parameters in capillary blood from fingers that had been exposed to a vibrating hand-held tool. This study involved nine healthy participants who had been exposed to vibration and an unexposed control group of six participants. Capillary blood samples were collected before and after vibration exposure for the exposed group, and repeated samples also from the control group. The exposed groups were exposed to vibration for a 15-min period or until they reached a 5.0 m/s² vibration dose. Analysis of blood status and differential counting of leucocytes was performed on the capillary blood samples. The results of the blood samples showed an increase in mean value for erythrocyte volume fraction (EVF), hemoglobin, red blood cell count, white blood cell count and neutrophils, as well as a decrease of mean cell volume, mean cell hemoglobin, and mean cell hemoglobin concentration. The increase of EVF and neutrophils was statistically significant for samples taken from the index finger but not the little finger. Even though the study was small it showed that an acute vibration exposure to the hands might increase EVF and neutrophilic granulocytes levels in the capillary blood taken from index fingers.