Spatiotemporal distribution and isomer profiles of perfluoroalkyl acids in airborne particulate matter in Chengdu City, China.
Sci Total Environ
; 689: 1235-1243, 2019 Nov 01.
Article
em En
| MEDLINE
| ID: mdl-31466162
ABSTRACT
Airborne particulate matter (APM) was collected in four seasons at five different areas of the city of Chengdu, China to study the spatial and seasonal contamination pattern of perfluoroalkyl acids (PFAAs). The results showed that ∑PFAA concentrations in Downtown Chengdu (mean value 297⯱â¯238â¯pg/m3) were higher than concentrations in suburban areas. The highest concentrations of PFAAs occurred during spring (97.5-709â¯pg/L; arithmetic mean concentration 297⯱â¯191â¯pg/L) while the lowest concentration occurred during autumn (9.27-105â¯pg/L; arithmetic mean concentration 41.1⯱â¯24.8â¯pg/L). Perfluorooctanoic acid (PFOA) was the main PFAA quantified during winter, summer and autumn, and perfluorononanoic acid (PFNA) was the predominant PFAA in spring. Relative humidity (RH) and average daily precipitation (PRE) showed significant negative correlations with PFAA concentrations in winter and summer, suggesting that they played an important role in controlling PFAA concentrations in APM. The linear structural isomer of PFOA (n-PFOA) was the most abundant isomer in APM in Chengdu, with the average proportion of 85.6%⯱â¯6.13%, higher than the proportion in ECF PFOA commercial products (74.3-77.6%). However, the consistent fingerprint of branched PFOA in the APM implies that ECF PFOA makes a significant contribution to the PFOA in APM. PFOS in the APM collected throughout the year had a mean proportion of 54.0⯱â¯8.81% of n-PFOS. This proportion of n-PFOS is lower than commercial ECF products (62.9-78.2%), suggesting an additional proportion of branched PFOS isomers in APM in Chengdu.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Sci Total Environ
Ano de publicação:
2019
Tipo de documento:
Article