METHODS: This cross-sectional study (SafeChrom) recruited non-smoking men and women from 14 companies with potential Cr(VI) exposure (n = 113) and controls from 6 companies without Cr(VI) exposure (n = 72). Inhalable Cr(VI) was measured by personal air sampling (outside of respiratory protection) in exposed workers. Total Cr was measured in urine (pre- and post-shift, density-adjusted) and red blood cells (RBC) (reflecting Cr(VI)) in exposed workers and controls. The Bayesian tool Expostats was used to assess risk and evaluate occupational exposure limit (OEL) compliance.
RESULTS: The exposed workers performed processing of metal products, steel production, welding, plating, and various chemical processes. The geometric mean concentration of inhalable Cr(VI) in exposed workers was 0.15 μg/m3 (95% confidence interval: 0.11-0.21). Eight of the 113 exposed workers (7%) exceeded the Swedish OEL of 5 μg/m3, and the Bayesian analysis estimated the share of OEL exceedances up to 19.6% for stainless steel welders. Median post-shift urinary (0.60 μg/L, 5th-95th percentile 0.10-3.20) and RBC concentrations (0.73 μg/L, 0.51-2.33) of Cr were significantly higher in the exposed group compared with the controls (urinary 0.10 μg/L, 0.06-0.56 and RBC 0.53 μg/L, 0.42-0.72). Inhalable Cr(VI) correlated with urinary Cr (rS = 0.64) and RBC-Cr (rS = 0.53). Workers within steel production showed the highest concentrations of inhalable, urinary and RBC Cr. Workers with inferred non-acceptable local exhaustion ventilation showed significantly higher inhalable Cr(VI), urinary and RBC Cr concentrations compared with those with inferred acceptable ventilation. Furthermore, workers with inferred correct use of respiratory protection were exposed to significantly higher concentrations of Cr(VI) in air and had higher levels of Cr in urine and RBC than those assessed with incorrect or no use. Based on the Swedish job-exposure-matrix, approximately 17 900 workers were estimated to be occupationally exposed to Cr(VI) today.
CONCLUSIONS: Our study demonstrates that some workers in Sweden are exposed to high levels of the non-threshold carcinogen Cr(VI). Employers and workers seem aware of Cr(VI) exposure, but more efficient exposure control strategies are required. National strategies aligned with the European strategies are needed in order to eliminate this cause of occupational cancer.
方法:这项横断面研究(SafeChrom)招募了来自14家具有潜在Cr(VI)暴露的公司的非吸烟男性和女性(n=113)和来自6家没有Cr(VI)暴露的公司的对照组(n=72)。通过暴露工人的个人空气采样(在呼吸保护之外)测量可吸入的Cr(VI)。测量尿液中的总Cr(移位前和移位后,在暴露的工人和对照组中进行密度调整)和红细胞(RBC)(反映Cr(VI))。使用贝叶斯工具Expostats评估风险并评估职业接触限值(OEL)的依从性。
结果:暴露的工人对金属制品进行加工,钢铁生产,焊接,电镀,和各种化学过程。暴露工人可吸入Cr(VI)的几何平均浓度为0.15μg/m3(95%置信区间:0.11-0.21)。113名暴露工人中有8名(7%)超过了5μg/m3的瑞典OEL,贝叶斯分析估计不锈钢焊工的OEL超标比例高达19.6%。班后尿中位数(0.60μg/L,第5-95百分位数0.10-3.20)和红细胞浓度(0.73μg/L,暴露组Cr的0.51-2.33)显着高于对照组(尿0.10μg/L,0.06-0.56和红细胞0.53μg/L,0.42-0.72)。可吸入Cr(VI)与尿Cr(rS=0.64)和RBC-Cr(rS=0.53)相关。钢铁生产中的工人显示出最高的可吸入浓度,尿和红细胞Cr。推断为不可接受的局部排气通气的工人显示出明显较高的可吸入Cr(VI),与推断可接受通气的尿液和红细胞Cr浓度相比。此外,推断正确使用呼吸保护的工人暴露于空气中的Cr(VI)浓度明显高于不正确或不使用呼吸保护的工人,并且尿液和红细胞中的Cr水平高于评估的工人.根据瑞典的工作暴露矩阵,估计今天约有17.900名工人在职业上接触Cr(VI)。
结论:我们的研究表明,瑞典的一些工人暴露于高水平的非阈值致癌物Cr(VI)。雇主和工人似乎意识到Cr(VI)暴露,但需要更有效的曝光控制策略。为了消除这种职业性癌症的原因,需要与欧洲战略保持一致的国家战略。