Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China; Synergy Innovation Institute of GDUT, Shantou 515041, Guangdong, China.
Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China.
Sci Total Environ. 2023 Dec 15;904:166725. doi: 10.1016/j.scitotenv.2023.166725. Epub 2023 Aug 30.
Airborne particles can spread quickly and enter human respiratory system via inhalation, causing chronic diseases, even cancer. Although recent studies have informed of toxicity of various pollutants, understanding the transport and deposition characteristics of particles in lower respiratory tract is still challenging. The current study proposes a novel model to simulate flow field change from the entrance of lower respiratory tract to pulmonary acinus, while studying particle transport and deposition characteristics. This model for lower respiratory tract with several bronchial extensions containing virtual pulmonary acinus is calculated using computational fluid dynamics and dynamics mesh. The results showed that in the first 10 generations of the lower respiratory tract, vortices and gravity interfered with particles' trajectory, affecting particle deposition distribution. For the first to the tenth-generation respiratory tract, coarse particles were deposited throughout almost the whole respiratory tract model. In contrast, ultrafine particles did not deposit in the higher-generation respiratory tract. The particle enrichment ability of various lobes was uneven with three particle deposition fraction variation patterns. Virtual pulmonary acinus influenced particle deposition and distribution because of vortex ring's trapped ability during expansion and contraction. This new attempt to build a virtual pulmonary acinus model to simulate particle deposition effects in human respiratory system may provide a reference for studying the toxicities of inhalable particles in the exposed human body.
空气中的悬浮粒子可经吸入而快速传播并进入人体呼吸系统，导致慢性疾病甚至癌症。尽管最近的研究已经揭示了各种污染物的毒性，但了解粒子在下呼吸道中的传输和沉积特征仍然具有挑战性。本研究提出了一种新的模型，用于模拟从下呼吸道入口到肺泡的流场变化，同时研究粒子的传输和沉积特征。使用计算流体动力学和动力网格计算了包含几个支气管分支的虚拟肺泡的下呼吸道模型。结果表明，在 10 代下呼吸道中，涡流和重力干扰了粒子的轨迹，影响了粒子的沉积分布。对于第一代到第十代呼吸道，粗粒子沉积在几乎整个呼吸道模型中。相比之下，超细粒子在较高代呼吸道中不会沉积。各叶的颗粒富集能力不均匀，存在三种颗粒沉积分数变化模式。由于涡环在扩张和收缩过程中的捕获能力，虚拟肺泡影响了粒子的沉积和分布。这种构建虚拟肺泡模型以模拟人呼吸道中粒子沉积效应的新尝试，可能为研究暴露于人体中的可吸入颗粒的毒性提供参考。
