Division of Environmental Health Sciences, University of Minnesota, Minneapolis, MN, USA.
Department of Environmental Health and Engineering, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
Ann Work Expo Health. 2020 Nov 16;64(9):993-1006. doi: 10.1093/annweh/wxaa074.
A variety of dimensions (lengths and widths) of elongate mineral particles (EMPs) have been proposed as being related to health effects. In this paper, we develop a mathematical approach for deriving numerical conversion factors (CFs) between these EMP exposure metrics and applied it to the Minnesota Taconite Health Worker study which contains 196 different job exposure groups (28 similar exposure groups times 7 taconite mines). This approach comprises four steps: for each group (i) obtain EMP dimension information using ISO-TEM 10312/13794 analysis; (ii) use bivariate lognormal distribution to characterize overall EMP size distribution; (iii) use a Bayesian approach to facilitate the formation of the bivariate lognormal distribution; (iv) derive conversion factors between any pair of EMP definitions. The final CFs allow the creation of job exposure matrices (JEMs) for alternative EMP metrics using existing EMP exposures already characterized according to the National Institute of Occupational Safety and Health (NIOSH)-defined EMP exposure metric (length >5 µm with an aspect ratio ≥3.0). The relationships between the NIOSH EMP and other EMP definitions provide the basis of classification of workers into JEMs based on alternate definitions of EMP for epidemiological studies of mesothelioma, lung cancer, and non-malignant respiratory disease.
已经提出了各种长度和宽度的细长矿物颗粒 (EMPs)，认为它们与健康影响有关。在本文中，我们开发了一种数学方法来推导这些 EMP 暴露度量之间的数值转换因子 (CFs)，并将其应用于明尼苏达州铁矿工人研究，该研究包含 196 个不同的职业暴露组（28 个相似的暴露组乘以 7 个铁矿）。该方法包括四个步骤：对于每个组 (i) 使用 ISO-TEM 10312/13794 分析获得 EMP 尺寸信息；(ii) 使用双变量对数正态分布来描述整体 EMP 大小分布；(iii) 使用贝叶斯方法促进双变量对数正态分布的形成；(iv) 推导任意两个 EMP 定义之间的转换因子。最终的 CFs 允许使用根据美国国家职业安全与健康研究所 (NIOSH) 定义的 EMP 暴露度量（长度>5 µm，纵横比≥3.0）已经描述的现有 EMP 暴露来创建替代 EMP 度量的职业暴露矩阵 (JEM)。NIOSH EMP 与其他 EMP 定义之间的关系为基于 EMP 的替代定义将工人分类到 JEM 提供了基础，用于间皮瘤、肺癌和非恶性呼吸道疾病的流行病学研究。
