Nethercott J, Paustenbach D, Adams R, Fowler J, Marks J, Morton C, Taylor J, Horowitz S, Finley B
Johns Hopkins University, Baltimore, MD.
Occup Environ Med. 1994 Jun;51(6):371-80. doi: 10.1136/oem.51.6.371.
Over the past 60 years, dose-response patch test studies by various methods have been conducted in an attempt to identify the minimum elicitation threshold (MET) concentration of hexavalent chromium (Cr(VI)) that produces an allergic response in Cr(VI) sensitive subjects. These data are not adequate, however, to provide an accurate estimate of the MET because of the variability in the patch testing techniques and the variability in diagnostic criteria used. Furthermore, the data were not reported in terms of mass of allergen per surface area of skin (mg Cr/cm2-skin), which is necessary for conducting occupational or environmental health risk assessments. Thus the purpose of this study was to determine the MET (mg allergen/cm2) for Cr(VI) and trivalent chromium (Cr(III)) by patch testing techniques. A patch test method that delivers a controlled amount of allergen per surface area of skin was used. A group of 54 Cr(VI) sensitised volunteers were patch tested with serial dilutions of Cr(VI) and Cr(III) to determine the cumulative response rate at several concentrations. The results indicate that the 10% MET for Cr(VI) based on the cumulative response was 0.089 micrograms Cr(VI)/cm2-skin. Only one of the 54 volunteers may have responded to 33 micrograms Cr(III)/cm2-skin, otherwise Cr(III) was unable to produce allergic contact dermatitis in these highly sensitive volunteers. Two supplemental studies were also conducted to assess whether the surface area of the patch and the concentration of Cr(VI) in the patch (related to patch thickness) were likely to influence the results. The data from these studies were used to assess the risk of developing allergic contact dermatitis due to contact with Cr(VI) and Cr(III) in soil. The findings indicated that soil concentrations at least as high as 450 ppm Cr(VI) and 165,000 ppm Cr(III) should not pose an allergic contact dermatitis hazard for at least 99.99% of the people in the community who might be exposed.
在过去60年里，已通过各种方法开展了剂量反应斑贴试验研究，试图确定六价铬（Cr(VI)）在对Cr(VI)敏感的受试者中引发过敏反应的最低激发阈值（MET）浓度。然而，由于斑贴试验技术的变异性以及所使用诊断标准的变异性，这些数据不足以准确估计MET。此外，这些数据未按照每皮肤表面积的变应原质量（mg Cr/cm² - 皮肤）来报告，而这对于进行职业或环境卫生风险评估是必要的。因此，本研究的目的是通过斑贴试验技术确定Cr(VI)和三价铬（Cr(III)）的MET（mg变应原/cm²）。使用了一种能在每皮肤表面积递送可控量变应原的斑贴试验方法。一组54名对Cr(VI)致敏的志愿者用Cr(VI)和Cr(III)的系列稀释液进行斑贴试验，以确定几个浓度下的累积反应率。结果表明，基于累积反应的Cr(VI)的10% MET为0.089微克Cr(VI)/cm² - 皮肤。54名志愿者中只有一人可能对33微克Cr(III)/cm² - 皮肤有反应，否则Cr(III)无法在这些高度敏感的志愿者中引发过敏性接触性皮炎。还进行了两项补充研究，以评估斑贴的表面积和斑贴中Cr(VI)的浓度（与斑贴厚度有关）是否可能影响结果。这些研究的数据用于评估因接触土壤中的Cr(VI)和Cr(III)而发生过敏性接触性皮炎的风险。研究结果表明，对于社区中至少99.99%可能接触的人群，土壤中Cr(VI)浓度至少高达450 ppm和Cr(III)浓度至少高达十六万五千ppm时，不应构成过敏性接触性皮炎危害。
