University of Bordeaux, Inserm UMR 1219 EPICENE Team, Bordeaux Population Health Research Center, Bordeaux, France.
Environmental Epidemiology Division, Institute for Risk Assessment Sciences, Utrecht University, Nieuw Gildestein Yalelaan, Utrecht, The Netherlands.
Ann Work Expo Health. 2019 Nov 13;63(9):1013-1028. doi: 10.1093/annweh/wxz067.
The aim of this work was to build a job-exposure matrix (JEM) using an international coding system and covering the non-thermal intermediate frequency (IF) (3-100 kHz, named IFELF), thermal IF (100 kHz-10 MHz, named IFRF), and radiofrequency (RF) (>10 MHz) bands.
Detailed occupational data were collected in a large population-based case-control study, INTEROCC, with occupations coded into the International Standard Classification of Occupations system 1988 (ISCO88). The subjects' occupational source-based ancillary information was combined with an existing source-exposure matrix and the reference levels of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) for occupational exposure to calculate estimates of level (L) of exposure to electric (E) and magnetic (H) fields by ISCO88 code and frequency band as ICNIRP ratios (IFELF) or squared ratios (IFRF and RF). Estimates of exposure probability (P) were obtained by dividing the number of exposed subjects by the total number of subjects available per job title.
With 36 011 job histories collected, 468 ISCO88 (four-digit) codes were included in the JEM, of which 62.4% are exposed to RF, IFRF, and/or IFELF. As a reference, P values for RF E-fields ranged from 0.3 to 65.0% with a median of 5.1%. L values for RF E-fields (ICNIRP squared ratio) ranged from 6.94 × 10-11 to 33.97 with a median of 0.61.
The methodology used allowed the development of a JEM for high-frequency electromagnetic fields containing exposure estimates for the largest number of occupations to date. Although the validity of this JEM is limited by the small number of available observations for some codes, this JEM may be useful for epidemiological studies and occupational health management programs assessing high-frequency electromagnetic field exposure in occupational settings.
本研究旨在建立一个职业暴露矩阵（JEM），该矩阵使用国际编码系统，涵盖非热中频（3-100 kHz，命名为 IFELF）、热中频（100 kHz-10 MHz，命名为 IFRF）和射频（RF）（>10 MHz）频段。
详细的职业数据是在一项大型基于人群的病例对照研究 INTEROCC 中收集的，该研究将职业编码为国际标准职业分类系统 1988 年版（ISCO88）。研究对象基于职业来源的辅助信息与现有的源-暴露矩阵和国际非电离辐射防护委员会（ICNIRP）针对职业暴露的参考水平相结合，以计算按 ISCO88 代码和频段计算的电场（E）和磁场（H）水平的暴露估计值（L），其比值命名为 ICNIRP 比值（IFELF）或平方比值（IFRF 和 RF）。暴露概率（P）的估计值通过将暴露组的数量除以每个职业头衔的总人数来获得。
共收集了 36011 份职业史，该 JEM 中包含 468 个 ISCO88（四位数）代码，其中 62.4% 的代码暴露于 RF、IFRF 和/或 IFELF。作为参考，RF 电场的 P 值范围为 0.3-65.0%，中位数为 5.1%。RF 电场的 L 值（ICNIRP 平方比）范围为 6.94×10-11 至 33.97，中位数为 0.61。
该研究采用的方法允许建立一个包含迄今为止最多职业的高频电磁场暴露估计值的 JEM。尽管由于某些代码的可用观测值数量较少，该 JEM 的有效性受到限制，但该 JEM 可能对评估职业环境中高频电磁场暴露的流行病学研究和职业健康管理计划有用。
