Center for Public Health and Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency, Durham, NC, USA.
Oak Ridge Associated Universities, Oak Ridge, TN, USA.
Inhal Toxicol. 2020 Jan;32(1):1-13. doi: 10.1080/08958378.2020.1725187. Epub 2020 Feb 26.
Diesel exhaust is a complex mixture comprised of gases and particulate matter and is a contributor to ambient air pollution. To reduce health risks, recent changes in diesel engine technology have significantly altered the composition of diesel exhaust, primarily by lowering emissions of particulate matter. However, animal toxicological studies continue to report health effects following exposure to diesel exhaust from engines employing particulate filters. The cause of these effects remains unclear. To gain an understanding of the role of both particle-filtered and whole diesel exhaust on specific health outcomes, we conducted a systematic review in which we examined animal toxicological and controlled human exposure studies that included a comparison between inhalation of particle-filtered and whole diesel exhaust on any health endpoint. We identified 26 studies that met both the inclusion and study evaluation criteria. For most health outcomes, the particle filtration methods employed in the included studies did not appreciably attenuate the health effects associated with exposure to whole diesel exhaust. There were also several health endpoints for which significant effects were associated with exposure to either particle-filtered or whole diesel exhaust, but not to both. Overall, the results from this systematic review demonstrate that exposure to different components in diesel exhaust can have distinct and independent health effects. Thus, to better inform human health risk assessments, future studies aimed at elucidating the health effects from diesel exhaust should include exposure to both particle-filtered and whole diesel exhaust.
柴油机废气是一种由气体和颗粒物组成的复杂混合物，是造成环境空气污染的原因之一。为了降低健康风险，柴油机技术的最新变化显著改变了柴油机废气的组成，主要是通过降低颗粒物的排放。然而，动物毒理学研究继续报告在使用颗粒物过滤器的发动机排放的柴油机废气暴露后出现健康影响。这些影响的原因仍不清楚。为了了解带和不带颗粒过滤器的柴油机废气对特定健康结果的影响，我们进行了一项系统评价，其中我们检查了动物毒理学和受控人体暴露研究，这些研究包括在任何健康终点比较吸入带和不带颗粒过滤器的柴油机废气。我们确定了 26 项符合纳入和研究评估标准的研究。对于大多数健康结果，纳入研究中使用的颗粒过滤方法并没有明显减轻暴露于全柴油机废气相关的健康影响。还有一些健康终点与暴露于带或不带颗粒过滤器的柴油机废气都有关，而不是两者都有关。总体而言，这项系统评价的结果表明，柴油机废气中不同成分的暴露会产生不同且独立的健康影响。因此，为了更好地为人类健康风险评估提供信息，未来旨在阐明柴油机废气健康影响的研究应包括暴露于带和不带颗粒过滤器的柴油机废气。
