雾霾超细颗粒物的健康效应

Recently, the heavy haze weather frequently attacked the majority of Chinese cities throughout the country. Research results have shown clear associations between short-term or long-term exposure to ambient fine particles (FPs, PM_2.5) and the increased incidence and mortality of cardiovascular or respiratory diseases. However, the ambient ultrafine particles (UFPs, PM_0.1) are dominant contributors to particle number in haze weather. Compared with FPs, UFPs could be inhaled and deposited more deeply into the lung, and may carry more toxicants and poses larger interface with biological systems. So, it has been proposed that UFPs are more harmful to human health than bigger ones, and their health effects warrant further comprehensive assessment. In the last decade, nanotoxicology has been developed quickly. By taking advantage of new conception, new knowledge and methodology from nanotoxicology studies, we here discuss comprehensively the UFPs’ health effects on respiratory and cardiovascular systems. We also try to identify the further research priorities and provide suggestions when studying health effects of ambient UFP in China: (1) systematic study of associations between physicochemical characteristics of ambient UFPs (such as resources, components, structures, sizes, surface, interface, et al.) and health effects, especially associations among chemical conversion, biological behavior, toxicological response and underlying mechanisms; (2) systematic appreciation of small-size-effects, surface effects, interface effects, multi- component synergistic effects and effects of multiple weak interactions for ambient UFPs; (3) systematic assessment of health effects of ambient UFPs on potential susceptible populations (for example, children, the elderly and patients with cardiovascular and pulmonary diseases) and relevant triggering mechanisms; (4) systematic establishment of analytical methods and technologies for health effects studies, especially development of integrated source apportionment methods and on-line analytical methods and technologies for health effects analysis; (5) Nanotoxicology has evolved comparatively systematic and complicated research methodologies, experimental techniques and basic knowledge, which will be of great enlightenment for ambient UFP health effects studies, although ambient UFPs and their structures, components and surface characteristics are easily affected by factors such as resources, seasons and meteorology; (6) Large-scale cohort studies of ambient UFPs (PM_0.1) health effects should be conducted at the same time when the cohort studies of ambient FPs (PM_2.5) health effects are performed. Fast action will benefit the knowledge pool of ambient UFPs health effects with our specific pollution background, and appropriate measures can be taken to alleviate harms. For that end, the close collaborations among atmospheric researchers, environmental protection department staff working on atmospheric monitoring and health science researchers are of most importance.