Abstract

Ultrafine particles (UFPs) with an aerodynamic diameter of <0.1 µm are emerging as the most dominant and abundant particulate matter. Human exposure to these particles has increased dramatically, especially in the indoor environment as most of the population spend 80 to 90% time in the indoor environment. Due to the small size, it is believed that these particles will impose more dangerous and aggressive health impacts. However, knowledge of UFPs is still lacking as most of the previous studies focused on PM₁₀ and PM_2.5. The current article aims to provide a critical overview of UFPs sources, composition, physicochemical properties, potential exposure route, toxicity mechanisms, and health impacts to identify the research gaps and future research directions and perspectives. It is commonly observed that inhalation is the dominant route of exposure. Inhaled ultra-fine particles can penetrate deep into the respiratory track, resulting in adverse health impacts, ranging from normal transient of respiratory problems to cardiovascular and respiratory mortality and morbidity, lung cancer, brain disease, mutagenic and carcinogenic impacts. Due to the large surface area, these particles can transport a variety of toxins causing tissue and cell injury, leading to enhanced oxidative stress and inflammation. In order to overcome the environmental burden and health consequences attributed to ultrafine particles, proper air quality guidelines should be introduced and it is suggested that future research should focus on the relationship between health symptoms and UFPs physicochemical properties, especially the mechanics of chemical transformation in human body, their biological behavior, and toxicological effect.

摘要

空气动力学直径 <0.1 µm 的超细颗粒 (UFP) 正在成为最主要和最丰富的颗粒物。人类对这些颗粒的暴露急剧增加，尤其是在室内环境中，因为大多数人在室内环境中度过 80% 到 90% 的时间。由于尺寸小，据信这些颗粒会对健康造成更危险和更具侵略性的影响。然而，由于之前的大多数研究都集中在 PM ₁₀和 PM _2.5，因此仍然缺乏对 UFP 的了解. 本文旨在对 UFP 的来源、成分、理化特性、潜在接触途径、毒性机制和健康影响进行批判性概述，以确定研究差距和未来的研究方向和前景。通常观察到，吸入是主要的暴露途径。吸入的超细颗粒物可以深入呼吸道，对健康造成不利影响，从正常短暂的呼吸系统问题到心血管和呼吸系统的死亡率和发病率、肺癌、脑部疾病、诱变和致癌影响。由于表面积大，这些颗粒可以运输各种毒素，导致组织和细胞损伤，导致氧化应激和炎症增强。