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A comprehensive survey was conducted to Masson pine ( Pinus massoniana L.) needles widely distributed in Shanghai in order to investigate the levels and homologue group patterns of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs), to identify and quantitatively assess source contributions to the total CPs in pine needle samples. The concentration ranged from not detected (ND) to 13,600 ng g − 1 with a geometric mean (GM) value of 63.7 ng g − 1 for ΣSCCPs, from 12.4 to 33,500 ng g − 1 with a GM value of 677 ng g − 1 for ΣMCCPs, and from 14.0 to 45,700 ng g − 1 with a GM value of 768 ng g − 1 for total CPs. For different sampling units, the pollution levels both for SCCPs and MCCPs in pine needles were in the same orders: Pudong > suburbs > Puxi > Chongming. These significant differences in SCCPs and MCCPs among four sampling units could be associated with difference in industrial activities and to some extent also in population density. All pine needle samples ( n = 131) were divided into 2 groups by hierarchical cluster analysis (HCA) for SCCPs and MCCPs, the most abundant homologue groups in the bulk of pine needle samples were C 11 Cl 5 − 7 and C 13 Cl 5 − 7 for SCCPs, and C 14 Cl 7 − 8 and C 15 Cl 7 − 8 for MCCPs. Correlation analysis suggested that SCCPs and MCCPs in pine needles in the studied area may be derived from different sources. Four sources for pine needles were identified by the FA-MLR model; their relative contributions to the total CP burden in pine needles were 18.0% for F1 (attributed to commercial SCCP mixture), 42.2% for F2 (attributed to commercial MCCP mixture), 29.3% for F3 (attributed to LRAT), and 10.5% for F4 (unknown source). CP contamination of atmospheric air by point sources and long-range atmospheric transport in Shanghai should receive more attention by local government. [ABSTRACT FROM AUTHOR]

A comprehensive investigation was conducted to the urban (Pudong) and suburban soils in Shanghai. A total of 154 soil samples were analyzed for 26 PAHs including highly carcinogenic dibenzopyrenes (DBPs). The total concentrations ranged from 25.8 to 7380 μg kg −1 for Σ 26 PAHs and 18.8 to 6320 μg kg −1 for 16 USEPA priority PAHs (Σ 16 PAHs), respectively. The BaP toxic equivalent (BaP eq ) concentrations were between 6.41 and 2880 μg kg −1 for Σ 24 PAHs, 1.11 and 620 μg kg −1 for Σ 16 PAHs and 2.72 and 2250 μg kg −1 for Σ 4 DBPs. The high PAH contamination in green land soils might originate mainly from local road traffic and industrial activities, and sewage sludge application or waste water irrigation for soil. Seven sources of soil PAHs in Shanghai were identified by positive matrix factorization (PMF) model. The mean risk quotient (m-RQ) values indicated that there were medium to high ecological risks in 9.10% of soil samples, pyrene (Pyr), benzo[b]fluoranthene (BbF) and benz[a]anthracene (BaA) were the major ecological risk drivers under agricultural use. The cancer risk (CR) values were within the acceptable range at 35.7%, 35.1% and 31.2% of sampling sites for children, youths and adults, respectively. The total lifetime carcinogenic risk (TLCR) values at 57.8% of sampling sites were within the acceptable range. Overall, cancer risks of soil PAHs in all sampling sites in the studied area were below the highest acceptable risk, suggesting that soil PAHs are unlikely to pose a significant cancer risk for population based on ingestion, dermal contact and inhalation exposure pathways. [ABSTRACT FROM AUTHOR]