Abstract:
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.