Characterization of size resolved atmospheric particles in the vicinity of iron and steelmaking industries in China

(Graphical abstract)

China currently faces environmental challenges of lower air quality, partly as a result of industrial activities. The aim of this study was to investigate the role of iron and steelmaking facilities to regional air quality in four selected industry dominated urban centres in China. Nine different particle size ranges present in atmospheric particles collected from four sites in Kunming (KM), Wuhan (WH), Nanjing (NJ) and Ningbo (NB) were analysed and compared with particles collected at one background site at the Ningbo Nottingham University (UN) with very little industrial influence in China. Similar mass concentration levels of particulate matter PM_2.1 and PM_1.1 were found at the three sites near older iron and steelmaking plants (KM, WH and NJ). Significantly lower levels of PM_2.1 and PM_1.1 were collected at the fourth site (NB), which is near to a modern and coastal iron and steelmaking plant. The particles collected had the highest mass concentration in the aerodynamic diameter range of 3.3–9.0 μm for all sites, except for the background site (UN). Scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, and inductively coupled plasma were used to determine the surface morphology and particle chemistry. Al, Ca, Fe, K, Mg, Na and Zn were found as the most abundant elements in all samples. The enrichment factors show that elements As, Cd, Cr, Cu, Pb and Zn were significantly enriched in particles, especially in fine particles, posing an adverse impact on human health. This study can be used to assist the development of particle monitoring programmes in the vicinity of industrial areas and also help to establish an elemental modality dataset on the exposure and risk assessments of atmospheric particles.