Objective:To explore the bioaccessibility of the main metal components in welding fume welding fume in simulated lung fluid, and to evaluate the exposure level of each metal component in combination with the EPA inhalation exposure risk assessment model.Methods:In November 2022, the microscopic morphology characteristics of welding fumes were analyzed by scanning electron microscopy, the bioaccessibility of each metal component in lung fluid simulated normal and lung inflammatory states was analyzed by in vitro simulation method, and the exposure level of each metal component was calculated in combination with the EPA inhalation exposure risk assessment model.Results:The main metal components in carbon dioxide gas shielded welding fumes were Fe, Mn, Zn, Ti, Al, Cu, Cr, Cd, Ni and As, and the bioaccessibility in simulated normal lung interstitial fluid was 0.82%-1.84%, 5.07%-9.41%, 4.52%-7.23%, 5.10%-8.67%, 20.48%-29.60%, 5.27%-9.83%, 4.80%-7.56%, 0.07%-1.08%, 6.48%-13.84% and 33.02%-42.81%. The bioaccessibility of the above metal components in the lung fluid under simulated lung inflammation was 14.79%-27.45%, 34.53%-46.11%, 35.31%-59.13%, 16.45%-22.51%, 60.78%-76.51%, 26.58%-34.12%, 15.32%-25.87%, 2.0%-5.7%, 34.77%-43.33% and 71.34%-88.36%, respectively. Compared with the simulated lurg interstitial fluid, the bioaccessibility of metal components in the lung fluid under the simulated inflammatory state was increased, and the difference was statistically significant ( P<0.05). The average daily exposure dose Mn in the two simulated lung fluids exceeded the inhalation reference limit (>50 times), and the average daily exposure dose Ti and Cr in the simulated lung inflammation exceeded the reference limit (>1.3 times) . Conclusion:Attention should be paid to the bioaccessibility characteristics of metal components in the exposure level and hazard assessment of welding fumes.

Objective:To explore the bioaccessibility of the main metal components in welding fume welding fume in simulated lung fluid, and to evaluate the exposure level of each metal component in combination with the EPA inhalation exposure risk assessment model.Methods:In November 2022, the microscopic morphology characteristics of welding fumes were analyzed by scanning electron microscopy, the bioaccessibility of each metal component in lung fluid simulated normal and lung inflammatory states was analyzed by in vitro simulation method, and the exposure level of each metal component was calculated in combination with the EPA inhalation exposure risk assessment model.Results:The main metal components in carbon dioxide gas shielded welding fumes were Fe, Mn, Zn, Ti, Al, Cu, Cr, Cd, Ni and As, and the bioaccessibility in simulated normal lung interstitial fluid was 0.82%-1.84%, 5.07%-9.41%, 4.52%-7.23%, 5.10%-8.67%, 20.48%-29.60%, 5.27%-9.83%, 4.80%-7.56%, 0.07%-1.08%, 6.48%-13.84% and 33.02%-42.81%. The bioaccessibility of the above metal components in the lung fluid under simulated lung inflammation was 14.79%-27.45%, 34.53%-46.11%, 35.31%-59.13%, 16.45%-22.51%, 60.78%-76.51%, 26.58%-34.12%, 15.32%-25.87%, 2.0%-5.7%, 34.77%-43.33% and 71.34%-88.36%, respectively. Compared with the simulated lurg interstitial fluid, the bioaccessibility of metal components in the lung fluid under the simulated inflammatory state was increased, and the difference was statistically significant ( P<0.05). The average daily exposure dose Mn in the two simulated lung fluids exceeded the inhalation reference limit (>50 times), and the average daily exposure dose Ti and Cr in the simulated lung inflammation exceeded the reference limit (>1.3 times) . Conclusion:Attention should be paid to the bioaccessibility characteristics of metal components in the exposure level and hazard assessment of welding fumes.

Background Workers in printing jobs are exposed to a variety of organic solvents at low levels for a long period of time. Previous studies have focused on the main components in Material Safety Data Sheet or high-risk occupational hazardous agents, but have not been able to comprehensively and accurately identify the volatile organic compounds (VOCs) in printing jobs. Objective To qualitatively analyze the VOCs in ink, detergent, varnish, fountain solution, and other raw and auxiliary materials by headspace gas chromatography-mass spectrometry, and to accurately identify the occupational hazardous agents in printing jobs. Methods Raw and auxiliary materials used in printing jobs in 6 printing enterprises in Shanghai were sampled by headspace sampling, analyzed by gas chromatography-mass spectrometry, identified by National Institute of Standards & Technology ( NIST) Standard Library and retention time, and quantified by peak area percentage. Results A total of 181 VOCs were reported in the headspace of 25 organic solvent samples, with a total detection frequency of 337 items and 13.2±12.3 VOCs per sample. The most frequently detected VOCs category was naphthene, with a total of 69 items detected (22.5%), dominated by cyclohexane. The characteristics of VOCs components in the headspace of different types of samples were different. The largest number of VOCs was detected in the headspace of detergent samples, with an average of 31.5 VOCs detected. The characteristic components in detergent were aromatic hydrocarbons and ester compounds; alcohols were the characteristic components in varnish; and ester compounds were the characteristic components in ink. The results of cluster analysis showed that ethanol, toluene, ethyl acetate, cyclohexane, and acetone were occupational hazardous agents with high levels of exposure in printing jobs. Conclusion Many kinds of organic solvents used in printing process are difficult to identify by traditional methods. Headspace gas chromatography-mass spectrometry can help to accurately identify VOCs in the workplace, so as to more accurately assess the occupational hazards, and to provide a technical basis for guiding occupational health monitoring and implementing corresponding occupational health risk management and control.