Key Laboratory of Environmental Medicine Engineering of Ministry of Education, Southeast University, Nanjing 210009, China.
Key Laboratory of Environmental Medicine Engineering of Ministry of Education, Southeast University, Nanjing 210009, China; Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210000, Jiangsu, China; Jiangsu Preventive Medical Association, Nanjing 210000, Jiangsu, China.
Sci Total Environ. 2024 May 20;926:171719. doi: 10.1016/j.scitotenv.2024.171719. Epub 2024 Mar 13.
In the majority of occupational settings within China, the concentrations of benzene are observed to fall markedly below the demarcated detection thresholds. Employing traditional risk assessment models, the presence of exceptionally low airborne benzene exposure concentrations may infuse heightened degrees of uncertainty. Consequently, the necessity arises to investigate risk assessment methodologies more apt for the prevalent exposure environment among employees. In the present study, a pharmacokinetic model premised on urinary benzene metabolites (S-PMA and t, t-MA) was employed to ascertain a more precise daily airborne benzene exposure concentration per individual. This value was integrated into the linear multistage model as the 'internal exposure concentration'. In conjunction with the U.S National Environmental Protection Agency's (EPA) inhalation risk assessment model predicated on the external exposure concentration, the Singapore Ministry of Manpower's (MOM) model, and the linear multistage (LMS) model, the carcinogenic and non-carcinogenic effects of benzene were evaluated for 1781 benzene-exposed employees across 76 enterprises in Jiangsu Province. Findings suggest that in the linear multilevel model assessment, the cancer risk levels based on t, t-MA and S-PMA were higher in the printing and recording media reproduction industry, automobile manufacturing industry, general equipment manufacturing industry and the furniture manufacturing industry (median 2.842 × 10, 2.819 × 10, 2.809 × 10, and 2.678 × 10), which align more consistently with the actual benzene exposure circumstances of each industry's study participants, with overall risk levels calculated by the linear multistage model exceeding those of the EPA inhalation risk assessment model and the MOM model. This implies that the linear multistage model of internal exposure, based on the reciprocal of benzene biomarkers S-PMA and t, t-MA for airborne benzene exposure, presents enhanced sensitivity and suitability for the current occupational health risk assessment of workers. Without doubt, biomarker-based benzene exposure risk assessment emerges as the optimal choice.
在中国大多数职业环境中，空气中的苯浓度明显低于划定的检测阈值。采用传统的风险评估模型，极低浓度的空气中苯暴露可能会增加高度不确定性。因此，需要研究更适合员工普遍暴露环境的风险评估方法。在本研究中，采用基于尿中苯代谢物（S-PMA 和 t，t-MA）的药代动力学模型来确定每个个体更准确的每日空气中苯暴露浓度。该值作为“内部暴露浓度”被整合到线性多阶段模型中。结合美国国家环境保护局（EPA）基于外部暴露浓度的吸入风险评估模型、新加坡人力部（MOM）模型和线性多阶段（LMS）模型，对江苏省 76 家企业的 1781 名苯暴露员工进行了苯的致癌和非致癌作用评估。结果表明，在线性多水平模型评估中，基于 t，t-MA 和 S-PMA 的癌症风险水平在印刷和记录媒体复制业、汽车制造业、通用设备制造业和家具制造业中更高（中位数分别为 2.842×10、2.819×10、2.809×10 和 2.678×10），这更符合各行业研究参与者的实际苯暴露情况，整体风险水平由线性多阶段模型计算的风险水平超过 EPA 吸入风险评估模型和 MOM 模型。这意味着基于空气中苯暴露的苯生物标志物 S-PMA 和 t，t-MA 的倒数的线性多阶段内部暴露模型对当前工人职业健康风险评估具有更高的敏感性和适用性。毫无疑问，基于生物标志物的苯暴露风险评估是最佳选择。
