Characterization of PM10 and PM2.5 and Their Metals Content in Different Typologies of Sites in South-Eastern Italy

Atmosphere

Daniele Contini¹  Daniela Cesari¹  Antonio Donateo¹  Daniela Chirizzi¹ 

[1] Istituto di Scienze dell’Atmosfera e del Clima (ISAC), CNR, Str. Prv. Lecce-Monteroni km 1.2, 73100 Lecce, Italy; E-Mails:

关键词: PM_2.5;    PM₁₀;    metals concentrations;    enrichment factors;    Saharan dust events;   

DOI  :  10.3390/atmos5020435

来源: mdpi

【 摘 要 】

Samples of PM₁₀ and PM_2.5 were collected discontinuously between 2003 and 2010 at fifteen monitoring sites (urban, background, industrial) in the south-eastern part of Italy using a mobile laboratory. In total, 483 PM₁₀ and 154 PM_2.5 samples were collected and chemically analyzed for the determination of metal content. Data were used to investigate concentration differences among the typologies of sites, the seasonal patterns, and the influence of advection of Saharan dust (SD). PM₁₀ and PM_2.5 average concentrations increase from background to industrial and urban sites but the ratio PM_2.5/PM₁₀ is significantly lower (0.61 ± 0.10) in background sites. The average metals concentrations in PM₁₀ and in PM_2.5 do not show a clear dependence on site typology apart an increase in crustal elements in background sites and an increase in the enrichment factors of Ni and of Cr in PM₁₀ in industrial sites. Urban sites show a statistically significant increase of PM₁₀ average concentration during the cold seasons (autumn and winter), likely associated with the anthropogenic urban emissions, instead, the background sites show a decrease in concentrations during the cold seasons. This could be due to more frequent cases of SD observed in spring and summer periods that mainly influence background sites. The seasonal difference on the average concentration for industrial sites is not statistically significant. The SD cases influence both PM₁₀ and PM_2.5 concentrations but their effect is significantly larger on PM₁₀. Over the studied area, the effect is relatively limited on long-term average PM₁₀ (estimated increase of 3.2%) and PM_2.5 (estimated increase of 1.5%) concentrations but it is significant on daily concentrations. It is estimated an increase of 22% of the probability to overcome the air quality standard daily threshold for PM₁₀.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.