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In the China Bohai bay area, a Single anchor leg yoke mooring system (SYS) was mainly used for FPSO's permanent mooring due to the shallow water. This paper investigates the SYS failure and focus on the excessive wear that occurred to underwater turret bearings. The wear mechanism of bearing is researched by using morphology analysis and energy spectrum analysis. Nonlinear finite element analysis is performed to study the contact status between turret table and axial bearings considering the operational and extreme load condition. The comparison wear-test is carried out to clarify the contributions of eccentric load on the wear performance of axial bearing. Wear-test results indicate that eccentric load has a significant impact on wear of turret bearings. Eccentric wear also produce more abrasive particles to accelerate wear rate. A step-like is formed on bearing plate surface due to excessive wear. The failed bolts are attributed to stress corrosion crack under long-term shear fore caused by vessel surge motion. [ABSTRACT FROM AUTHOR]

Dietary intake is one of the major exposure pathways of polycyclic aromatic hydrocarbons (PAHs), especially in Chinese people because foods are often prepared with grilling and/or frying that would produce high levels of PAHs. In this paper, we assessed daily dietary intakes (DDI) of PAHs, using a “duplicate plate method”, among 100 Chinese urban residents. The DDI of benzo(a)pyrene ranged from 0.06 µg per day to 13.5 µg per day with a median of 0.69 µg per day, varying largely across subjects. The median Incremental Lifetime Cancer Risk (ILCR) attributable to PAH dietary intake was 6.65 × 10 −5 (4.41 × 10 −5 to 1.02 × 10 −4 as inter-quartile range). The contribution of several high-PAH containing foods like barbecued, smoked or deep-fried meats to the overall DDIs was about 13%. The use of raw foods may underestimate dietary intake of PAHs and associated exposure risk considerably. Results from foods sampled in different seasons suggested that seasonal variability within an individual may contribute notably to overall variability measured in a population and more future studies with longer-term investigation on food ingestion and pollutant exposure are needed. The study indicates that measuring actually consumed foods is more appropriate for dietary intake exposure assessment, and intra-individual variance should be taken into account during study design and data analysis. [ABSTRACT FROM AUTHOR]

Abstract: The concern about emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) from steel industrial parks has increased in the past decades. In this study, polyurethane foam (PUF)-disk based passive air samples were collected in and around a big steel industrial park of Anshan, Northeast China from June 2008 to March 2009. The levels, seasonal variations and potential sources of PCDD/Fs, PCBs and PBDEs in the atmosphere around the steel industrial complex were investigated, and potential contribution of these three groups of persistent organic pollutants (POPs) from iron and steel production was also assessed. The air concentrations of ∑17PCDD/Fs (summer: 0.02–2.77pgm−3; winter: 0.20–9.79pgm−3), ∑19PCBs (summer: 23.5–155.8pgm−3; winter: 14.6–81.3pgm−3) and ∑13PBDEs (summer: 2.91–10.7pgm−3; winter: 1.10–3.89pgm−3) in this targeted industrial park were relatively low in comparison to other studies, which implied that the industrial activities of iron and steel had not resulted in serious contamination to the ambient air in this area. On the whole, the air concentrations of PCDD/Fs in winter were higher than those of summer, whereas the concentrations of PCBs and PBDEs showed opposite trends. The result from principal component analysis indicated that coal combustion might be the main contributor of PCDD/F sources in this area. [Copyright &y& Elsevier]

Abstract: Air monitoring of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) was carried out in June 2008 and January 2009 to investigate the concentrations, profiles and estimating potential inhalation risks to the local residents around a steel plant area in northeast China. The air concentrations and WHO-TEQs of PCDD/Fs ranged 94–4944fgm−3 (average 1352fgm−3) and 3–247fgm−3 (average 81fgm−3), respectively. The WHO-TEQ concentrations of dioxin-like PCBs ranged 1–18fgm−3 (average 5fgm−3), contributing to 3.6–26% of the total TEQ. Higher PCDD/F concentrations were observed in the winter, whereas higher dioxin-like PCB concentrations were found in the summer. The seasonal trend can be related to the significant correlation between the concentrations of dioxins and the reciprocal of temperature (positive for PCDD/Fs, P <0.01; negative for dioxin-like PCBs, P =0.05). A significant positive correlation (P <0.0001) was found between the concentration of total suspended particulate (TSP) and PCDD/F concentrations, but not for PCB congeners. Although the steel plant sites showed higher dioxin levels than the residential and background areas, the PCDD/F levels in the atmosphere of the steel plant area was at a relatively low level. The results from this study provides further aid in evaluating the impact of steel plants as PCDD/Fs emission sources to the ambient air in China. [Copyright &y& Elsevier]