Using occupational studies to assess exposure-response relations in the low exposure region
该研究开发了两种方法，利用职业研究和生物标志物数据，改进低暴露区域的暴露-反应关系分析，并应用于苯与白血病研究，验证了方法的有效性。
<h3>Objectives</h3> The assessment of the effect of low level exposures on human health is a considerable challenge for risk assessment. This is mainly due to large uncertainty regarding the human dose-response relationship at low exposures. High quality occupational studies and biomarker data can play an important role in exposure-response analysis for the low-exposure region. <h3>Methods</h3> We developed approaches to improve the contribution of occupational studies to exposure-response analysis for the low-exposure region by a) developing a method for the assessment of the shape of the exposure response curve with a flexible meta-regression, and b) exploring the effect on exposure-response relations of integrating predictive models of relevant biomarkers of exposure into the epidemiological analysis of occupational studies. <h3>Results</h3> Application of the developed approaches on studies of benzene and leukaemia demonstrated that the flexible meta-regression allowed us to comprehensively evaluate the shape of the benzene-leukaemia exposure response relation in the low exposure region. Furthermore, substitution of biomarker levels for external estimates of benzene exposure reduced the heterogeneity between studies that provided risk estimates to the exposure-response analysis. <h3>Conclusions</h3> Application of the developed approaches in risk assessment would likely improve the overall quality of risk assessment for occupational and environmental exposures. However, a strong focus on high quality quantitative exposure assessment in the design of occupational epidemiological studies, and availability of relevant biomarkers is essential for the successful implementation of our approaches.