Environ Sci Technol
July 2009
Size fractionated particulate matter (PM) samples (including PM2.5 and PM10) were collected at Peking University in Northwestern Beijing, China for a 2 week period prior to the Olympics, during the 2 week period of the Olympics, and for a 4 week period following the 2008 Olympics, during both source control and nonsource control periods. PM10 concentrations in this study were high correlated with, but a factor of 1.
View Article and Find Full Text PDFThe enantiomeric signatures of organochlorine pesticides were measured in air masses from Okinawa, Japan and three remote locations in the Pacific Northwestern United States: Cheeka Peak Observatory (CPO), a marine boundary layer site on the Olympic Peninsula of Washington at 500 m above sea level (m.a.s.
View Article and Find Full Text PDFHistoric and current use pesticides (HUPs and CUPs), with respect to use in the United States and Canada, were identified in trans-Pacific and regional air masses at Mt. Bachelor Observatory (MBO), a remote high elevation mountain in Oregon's Cascade Range located in the United States, during the sampling period of April 2004 to May 2006 (n = 69), including NASA's INTEX-B campaign (spring 2006). Elevated hexachlorobenzene (HCB) and alpha-hexachlorocyclohexane (alpha-HCH) concentrations were measured during trans-Pacific atmospheric transport events at MBO, suggesting that Asia is an important source region for these HUPs.
View Article and Find Full Text PDFAtmospheric measurements of semivolatile organic compounds (SOCs) were made at Mt Bachelor Observatory (MBO), located in Oregon's Cascade Range, to understand the trans-Pacific and regional transport of SOCs from urban areas. High volume air sampling (approximately 644 m3 for 24 h periods) of both the gas and particulate phases was conducted from April 19, 2004 to May 13, 2006 (n = 69); including NASA's INTEX-B campaign in spring 2006 (n = 34 of 69). Air mass back trajectories were calculated and were used to calculate source region impact factors (SRIFs), the percentage of time the sampled air mass resided in a given source region.
View Article and Find Full Text PDFPressurized liquid extraction (PLE) was evaluated as a method for extracting semivolatile organic compounds (SOCs) from air sampling media, including quartz fiber filter (QFF), polyurethane foam (PUF), and a polystyrene divinyl benzene copolymer (XAD-2). Hansen solubility parameter plots were used to aid in the PLE solvent selection in order to both reduce coextraction of polyurethane and save time in evaluating solvent compatibility during the initial steps of method development. A PLE solvent composition of 75:25% hexane:acetone was chosen for PUF.
View Article and Find Full Text PDFSemivolatile fluorinated organic compounds (FOCs) were measured in archived air sample extracts collected from Hedo Station Observatory (HSO) on Okinawa, Japan and Mount Bachelor Observatory (MBO), Oregon U.S. during the springs of 2004 (MBO and HSO) and 2006 (MBO).
View Article and Find Full Text PDFTo estimate the emissions of anthropogenic semivolatile organic compounds (SOCs) from East Asia and to identify unique SOC molecular markers in Asian air masses, high-volume air samples were collected on the island of Okinawa, Japan between 22 March and 2 May 2004. Contributions from different source regions (China, Japan, the Koreas, Russia, and ocean/local) were estimated by use of source region impact factors (SRIFs). Elevated concentrations of hexachlorobenzene (HCB), hexachlorcyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs), and particulate-phase polycyclic aromatic hydrocarbons (PAHs) were attributed to air masses from China.
View Article and Find Full Text PDFCarbonyl reductase (CR) catalyzes the nicotinamide adenine dinucleotide phosphate (NADPH)-dependent reduction of several carbonyls. Anthracyclines used to treat cancer are reduced by CR at the C13 carbonyl and the resulting metabolites are implicated in the cardiotoxicity associated with anthracycline therapy. CR also is believed to have a role in detoxifying quinones, raising the question whether CR catalyzes reduction of anthracycline quinones.
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