DeVaughn Alissa, Go Leonard H T, Cohen Robert A, Shao Yuan
Division of Environmental and Occupational Health Sciences, School of Public Health, University of Illinois Chicago, Chicago, Illinois.
J Occup Environ Hyg. 2025 Feb;22(2):101-109. doi: 10.1080/15459624.2024.2421488. Epub 2024 Nov 25.
Engineered stone countertops, popularly known as quartz or artificial stone countertops, have gained significant attraction due to their durability and aesthetic appeal. However, due to their high crystalline silica content, the fabrication of these countertops poses severe health risks to workers, as evidenced by numerous global cases of silicosis. The study aimed to assess occupational exposure to respirable crystalline silica (RCS) among fabricators in Chicago and characterize the elemental composition and physical properties of engineered stone dust. Eight professional fabricators from two local stone workshops were recruited for the study. The exposure levels to RCS were assessed using the NIOSH 7500 method. Bulk dust samples were collected on-site, and the elemental composition of the dust was analyzed using X-ray fluorescence (XRF) and reported in stoichiometric oxide units. A set of real-time air monitors was used to measure particle size distribution, particulate matter (PM) concentrations, and ambient conditions in the workplace. A questionnaire was administered, and worker activities were recorded during the visits. Workers were found to be overexposed to respirable quartz in their workplaces, with time-weighted averaged (TWA) concentrations ranging from 11 to 203 µg/m, with a median concentration of 90 µg/m³. Seven samples (78%) exceeded the 50 µg/m TWA-8 hr occupational exposure limit for RCS. Engineered stone dust samples contain much higher silica content compared to natural stone dust (30%), with silica percentages ranging from 56% to 95%. Over 90% of the particles (90.3-98.7%) emitted from activities involving small hand tools were of size less than 2.5 µm. The use of respiratory protection was not observed during the visits. The study offers firsthand insights into the engineered stone fabrication industry. The findings reveal a combination of risk factors: elevated RCS concentrations, very high silica content in engineered stone, and a high prevalence of fine particles. These factors collectively pose significant health risks to workers that are unequaled in comparison to most other industries. The findings underscore the urgent need for regulatory measures to better protect workers' health in the engineered stone fabrication sector.
人造石台面，通常被称为石英或人造石台面，因其耐用性和美观性而备受关注。然而，由于其高结晶二氧化硅含量，这些台面的制造对工人构成了严重的健康风险，全球众多矽肺病案例就是证明。该研究旨在评估芝加哥制造商中可吸入结晶二氧化硅（RCS）的职业暴露情况，并表征人造石粉尘的元素组成和物理特性。从当地两家石材加工厂招募了八名专业制造商参与该研究。使用美国国家职业安全与健康研究所（NIOSH）7500方法评估RCS的暴露水平。现场采集大量粉尘样本，并使用X射线荧光（XRF）分析粉尘的元素组成，并以化学计量氧化物单位报告。使用一组实时空气监测器测量工作场所的粒径分布、颗粒物（PM）浓度和环境条件。进行了问卷调查，并在访问期间记录了工人的活动。研究发现，工人在工作场所中可吸入石英的暴露超标，时间加权平均（TWA）浓度范围为11至203微克/立方米，中位数浓度为90微克/立方米。七个样本（78%）超过了RCS的50微克/立方米TWA-8小时职业暴露限值。与人造石粉尘（30%）相比，人造石粉尘样本的二氧化硅含量要高得多，二氧化硅百分比范围为56%至95%。涉及小型手动工具的活动排放的颗粒中，超过90%（90.3-98.7%）的粒径小于2.5微米。访问期间未观察到工人使用呼吸防护设备。该研究为人造石制造行业提供了第一手见解。研究结果揭示了一系列风险因素：RCS浓度升高、人造石中二氧化硅含量极高以及细颗粒的高流行率。与大多数其他行业相比，这些因素共同给工人带来了巨大的健康风险。研究结果强调迫切需要采取监管措施，以更好地保护人造石制造部门工人的健康。
