A probabilistic approach for economic evaluation of occupational health and safety interventions: a case study of silica exposure reduction interventions in the construction sector

Knowledge, attitudes and practices regarding respirable silica exposure and personal protective equipment use among brick kiln workers in Nepal

OBJECTIVES

Brick kiln workers in Nepal are a neglected population who are exposed to high respirable silica concentrations, and few use interventions to reduce exposure. We aimed to characterise the prevalence of respiratory personal protective equipment (PPE) use, understand knowledge and attitudes towards kiln dust and respiratory PPE and identify factors associated with respiratory PPE use.

METHODS

We conducted a cross-sectional study in Bhaktapur, Nepal. We used simple random selection to identify 10 out of 64 total kilns and stratified random sampling of 30 households to enrol workers aged ≥14 years within selected kilns. Field workers surveyed participants using structured questionnaires. Our primary outcome was to characterise the prevalence of current respiratory PPE use and secondary outcomes were summaries of knowledge, attitudes and practice of PPE use.

RESULTS

We surveyed 83 workers (mean age 30.8 years, 77.1% male). Of these, 28.9% reported current respiratory PPE use at work, 3.6% heard of silicosis prior to the survey and 24.1% correctly identified the best respiratory PPE (N95, compared with surgical masks and barrier face coverings) for reducing dust exposure. Respiratory PPE users had higher income (mean monthly household income US$206 vs US$145; p=0.04) and education levels (25% vs 5.1% completed more than primary school; p=0.02) compared with non-users.

CONCLUSIONS

Respiratory PPE use was low. Workers had poor knowledge of kiln dust health effects and proper respiratory PPE. We highlight important barriers to PPE use, particularly knowledge gaps, which can guide future investigations to reduce the silicosis burden among brick kiln workers.

Evaluation of workplace exposure to respirable crystalline silica in road construction industries in Alberta

Occupational exposure to respirable crystalline silica (RCS) is common for several occupations in construction, not only because of its presence in many handling materials but also in processes such as grinding and sawing. This study investigated workplace exposure to RCS as quartz in industries and occupations within road construction in Alberta through the RCS monitoring database provided by the Alberta Roadbuilders and Heavy Construction Association (ARHCA) between 2007 and 2016. Descriptive statistics were calculated for exposure-related variables, and mixed model analysis was performed to determine factors affecting the exposure levels. Results showed that the highest exposed workers were in the sand and gravel industry (GM = 45 μg/m³). For worker occupations, geometric means ranged from 78 μg/m³ for crusher operators to 10 μg/m³ for concrete truck operators. The maximum exposure severity was 33.3 times the occupational exposure limit (OEL) for the sand and gravel and 31 times the OEL for tower operators. The results also showed the effect of seasonal variability on RCS exposure levels. The heterogeneous exposure results indicated significant room for improvement and that controls should focus more on the activity performed than the occupation to lower exposure to RCS levels in industries.

An occupational health survey on health utility and occupational diseases in Chinese university staff to inform cost-utility analysis

Background

The occupational health of university staff bears great social and economic value for which health utility is an indivisible aspect. Utility is also the primary data for the cost-utility analysis of occupational health programs. Health utility and occupational diseases have not been reported for the university staff in China. In the light of "Healthy China," we conducted this study aiming to (1) estimate the health utility of university staff to inform cost-utility analysis and (2) screen and identify potential occupational diseases for this occupation and examine their impacts on health.

Methods

An occupational health survey was conducted in a sample of working-age university staff. Participants were interviewed face-to-face using the WHO Health and Work Performance Questionnaire and the European Quality of Life 5 Dimensions (EQ-5D) instrument to measure health conditions and health utility, respectively. The univariate analysis included the t-test, chi-square test, and correlation techniques. Multivariate generalized linear models were applied to evaluate the significance of each health condition when controlling for other factors.

Results

The sample (n = 154) had a mean age of 40.65 years and consisted of slightly more women (51.30%). Participants attained a mean (standard deviation) health utility of 0.945 (0.073). The most affected domain was anxiety/depression with 62 (40.26%) participants reporting problems, followed by pain/discomfort which captured 60 (37.66%) staff with problems. Thus, pain and psychologically related conditions were prevalent. Multivariate models identified two conditions that can significantly reduce the health utility. The psychological/emotional conditions were associated with a utility loss of -0.067 (95%CI: -0.089, -0.045). The pain in body parts other than the head, neck, and back reduced the utility by -0.034 (95%CI: -0.055, -0.014).

Conclusion

Working-age staff in Chinese universities may have a lower health utility than the general population. Psychological conditions and musculoskeletal pain appear like occupational diseases. With the health utility data available, economic evaluation of cost-utility should follow up to facilitate the implementation of cost-effective programs.

MicroRNA-5100 Modulates Lung Cancer Cell Proliferation and Apoptosis via Inhibiting X-Linked Inhibitor of Apoptosis Protein (XIAP) Expression

This study assesses the miR-5100 expression and its function in human lung cancer. The expression of miR-5100 was analyzed by miScript miRNA method. Cancer cells were transfected with miR-5100 mimics (miR-5100), miR-5100 inhibitors (ASO-miR-5100), XIAP inhibitors (si-XIAP), negative controls (NC) followed by analysis of cell proliferation by MTT and apoptosis by flow cytometry, the expression of XIAP related proteins by Western blot. miR-5100’ target was predicted by bioinformatics website and verified by dual luciferase assay. Finally, a xenogeneic tumor inhibition model was established to detect tumor progression after treatments. Lung cancer cells and tissues exhibited significantly reduced miR-5100 level. Dual luciferase assay showed that miR-5100 bound XIAP 3′-UTR and reduced XIAP mRNA and protein level. Further, miR-5100 inhibited cell proliferation, increased apoptosis and the expression of cleaved-capsase-3 and cleaved-capsase-9, the XIAP downstream factor. Finally, miR-5100 inhibited tumor growth, decreased cellular proliferation and promoted apoptosis, accompanied by reduced XIAP expression in vivo. miR-5100 inhibits lung cancer cell proliferation and enhances apoptosis through inhibiting XIAP expression in vitro and in vivo.