Woods Hole Oceanographic Institution Christopher M. Reddy Front Page  |  Curriculum Vitae (external file)  |  Projects  |  Publications  |  Photo Gallery Publications » Oil Weathering after the Deepwater Horizon Disaster Led to the Formation of Oxygenated Residues » A non-targeted GCxGC/TOF-MS method and software for inventorying persistent and bioaccumulative contaminants in marine environments. » Comparison of GC-MS, GC-MRM-MS, and GC x GC to characterise higher plant biomarkers in Tertiary oils and rock extracts » Impact of the Deepwater Horizon oil spill on a deep-water coral community in the Gulf of Mexico » Beyond Fatty Acid Methyl Esters: Expanding the Renewable Carbon Profile with Alkenones from Isochrysis sp. » Thermogravimetry-Mass Spectrometry for Carbon Nanotube Detection in Complex Mixtures » Estimating Phospholipid Membrane–Water Partition Coefficients Using Comprehensive Two-Dimensional Gas Chromatography » The composition, origin and fate of complex mixtures in the maltene fractions of hydrothermal petroleum assessed by comprehensive two-dimensional gas chromatography. » Age of nitrogen deficient microalgal cells is a key factor for maximizing lipid content. » δ15N Enrichment Suggests Possible Source for Halogenated 1′-Methyl-1,2′-bipyrroles (MBPs) » Modern and fossil contributions to polycyclic aromatic hydrocarbons in PM2.5 from North Birmingham, Alabama in the southeastern U.S. » Floating oil-covered debris from Deepwater Horizon: identification and application » Chemical composition measurements quantify Deepwater Horizon hydrocarbon emissions and distribution in the marine environment. » Acoustic measurement of the Deepwater Horizon Macondo well flow rate » Rapid microbial respiration of oil from the Deepwater Horizon spill in offshore surface waters of the Gulf of Mexico » Composition and fate of gas and oil released to the water column during the Deepwater Horizon oil spill » Separation of 18alpha(H)-, 18beta(H)-oleanane and lupane by comprehensive two-dimensional gas chromatography » Organic micropollutants in marine plastics debris from the open ocean and remote and urban beaches » Biodegradation preference for isomers of alkylated naphthalenes and benzothiophenes in marine sediment contaminated with crude oil » Compound-specific bromine isotope compositions of one natural and six industrially synthesised organobromine substances » Analysis of petroleum compositional similarity using multiway principal components analysis (MPCA) with comprehensive two-dimensional gas chromatographic data » Contemporary 14C radiocarbon levels of oxygenated polybrominated diphenyl ethers (O-PBDEs) isolated in sponge-cyanobacteria associations » Analysis and Identification of Biomarkers and Origin of Color in a Bright Blue Crude Oil » Multiple Alkynes React with Ethylene To Enhance Carbon Nanotube Synthesis, Suggesting a Polymerization-like Formation Mechanism » Tracking Hydrocarbon Plume Transport and Biodegradation at Deepwater Horizon » Combining biomarker and bulk compositional gradient analysis to assess reservoir connectivity » Developing tools for risk assessment in protected species: Relative potencies inferred from competitive binding of halogenated aromatic hydrocarbons to aryl hydrocarbon receptors from beluga (Delphinapterus leucas) and mouse. » The M/V Cosco Busan spill: Source identification and short-term fate. » The Size, mass, and composition of plastic debris in the Western North Atlantic Ocean. » Plastic Accumulation in the North Atlantic Subtropical Gyre » Precursor gas chemistry determines the crystallinity of carbon nanotubes synthesized at low temperature. » Stable organobromine in marine sediments: New evidence of biogeochemical Br cycling. » Marine natural products, the halogenated 1'-methyl-1,2'-bipyrroles (MBPs), biomagnify in the Northwestern Atlantic. » Brominated flame retardants and organochlorine contaminants in winter flounder, harp and hooded seals, and North Atlantic right whales from the Northwest Atlantic Ocean. » Chemical compound class oil fingerprinting techniques using comprehensive two-dimensional gas chromatography (GC×GC). » Asphalt volcanoes as a potential source of methane to late Pleistocene coastal waters. » Molecular and isotopic analysis of motor oil from a biodiesel-driven vehicle » Early evaluation of potential environmental impacts of carbon nanotube synthesis by chemical vapor deposition. » Method for rapid localization of seafloor petroleum contamination using concurrent mass spectrometry and acoustic positioning. » Inferring black carbon concentrations in coastal seawater by observing pyrene fluorescence losses. » Organohalogen contaminants and metabolites in cerebrospinal fluid and cerebellum gray matter in short-beaked common dolphins and Atlantic white-sided dolphins from the western North Atlantic. » Weathering and the fallout plume of heavy oil from strong petroleum seeps near Coal Oil Point, CA. » Capabilities of direct sample introduction - comprehensive two-dimensional gas chromatography - time-of-flight mass spectrometry to analyze organic chemicals of interest in fish oils. » Black carbon in the ocean: Inputs and cycling of highly recalcitrant organic carbon in the Gulf of Maine. » Simultaneous quantification of multiple classes of organohalogen compounds in fish oils with direct sample introduction-comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry. » Nanoaggregates of asphaltenes in a reservoir crude oil. » Distribution patterns suggest biomagnification of halogenated 1'-methyl-1,2' -bipyrroles (MBPs). » Disentangling oil weathering at a marine seep using GCxGC; Broad metabolic specificity accompanies subsurface petroleum biodegradation. » Response of salt marsh grass to residual petroleum spilled 38 years ago in Wild Harbor, MA. » Radiocarbon as an inverse tracer of fossil fuel-derived contaminants in sediments. » Using GCxGC-FID to identify and quantify olefin-based drilling fluids in crude oils. » Vapour pressures, aqueous solubilities, Henry's Law constants, and octanol/water partition coefficients of a series of Mixed Halogenated Dimethyl Bipyrroles. » d13C and D14C values of terrestrial subsurface bacterial phospholipids reveal diverse carbon cycling pathways. » Method for rapid localization of seafloor petroleum contamination using concurrent mass spectrometry and acoustic positioning. » Resolving the composition and formation of unresolved complex mixtures extracted from late Archean metasediments by comprehensive two-dimensional gas chromatography (GC×GC). » Long-term consequences of residual petroleum on salt marsh grass. » Organic Pollutants: Presence and Effects in Humans and Marine Animals. » Effect of field exposure to 38-year old residual petroleum hydrocarbons on growth, condition index, and filtration rate of the ribbed mussel, Geukensia demissa. » Industrially synthesized single-walled carbon nanotubes: Compositional data for users, environmental risk assessments, and source apportionment. » Photochemical degradation of polycyclic aromatic hydrocarbons in oil films. » Determination of biodiesel blending percentages using natural abundance radiocarbon analysis: Testing the accuracy of retail biodiesel blends. » Expanding the range of dehalogenated 1’-methyl-1,2’-bipyrroles (MBPs) using GC/ECNI-MS and GC×GC/TOF-MS. » Visible-near-infrared spectroscopy by downhole fluid analysis coupled with two dimensional gas chromatography to address oil reservoir complexity.  » Relationships between carbon isotopic composition and mode of association of natural organic matter in marine sediments. » Compound specific 81Br/79Br analysis by capillary gas chromatography multi-collector inductively coupled plasma mass spectrometry (GC-MC-ICPMS). » Molecular evidence of late Archean Archaea and the presence of a deep biosphere. » Disentangling oil weathering using GC×GC. Part 2. Mass transfer calculations. » Disentangling oil weathering using GC×GC. Part 1. Chromatogram analysis. » Carbon and chlorine isotope effects during abiotic reductive dechlorination of polychlorinated ethanes. » Biodegradation and environmental behavior of biodiesel mixtures in the sea: An initial study. » Long-term biological effects of petroleum: Response of fiddler crabs to oil in salt marsh sediments. » Identification and quantification of alkene-based drilling fluids in crude oils by comprehensive two-dimensional gas chromatography with flame ionization detection. » Evaluation of gas chromatographic isotope fractionation and process contamination by carbon in compound- specific radiocarbon analysis. » The 1974 spill of the Bouchard 65 oil barge: Petroleum hydrocarbons persist in Winsor Cove salt marsh sediments. » Halogenated organic compounds in archived whale oil: A pre-industrial record. » Late Quaternary evidence for climatically driven hydrocarbon emissions. » Characterizing biodegradation and microbial metabolic activity in situ using natural abundance, molecular-level 14C analysis. » Oil spill source identification by comprehensive two-dimensional gas chromatography (GC×GC). » 14C in Methane and DIC in the deep terrestrial subsurface: Implications for the timing of microbial methanogenesis. » Natural  14C  in  Saccoglossus  Bromophenolosus  compared  to  its surrounding  sediments. » Expanding the range of brominated Q1 analogues.  » Temporal trends in anthropogenic and naturally produced brominated compounds in California sea lions, 1993 to 2003. » Humic substances and crude oil induce cytochrome P450 1A expression in the Amazonian fish species Colossoma macropomum (Tambaqui). » Tracking the weathering of an oil spill with comprehensive two-dimensional gas chromatography. » Identification of highly brominated analogues of Q1 in marine mammals. » Determination of HBCD, PBDEs and MeO-BDEs in California sea lions (Zalophus californianus) stranded between 1993 and 2003. » Radiocarbon dating of alkenones from marine sediments: I. Isolation protocol. » Spectral characterization of two bioaccumulated methoxylated polybrominated diphenyl ethers. » Estimating partitioning properties for a complete set of diesel fuel hydrocarbons using comprehensive two-dimensional gas chromatography retention indices. » Abundance, composition, and vertical transport of PAHs in marsh sediments. » The West Falmouth oil spill: 100 kg of oil persists in marsh sediments. » Combustion-derived polycyclic aromatic hydrocarbons in the environment – A review. » High-resolution historical records from Pettaquamscutt River basin sediments. 1. Chronology and record of 137Cs released by the Chernobyl accident. » High-resolution historical records from Pettaquamscutt River basin sediments. 2. Pb isotopes reveal potential new stratigraphic marker. » Contribution of biomass burning to polycyclic aromatic hydrocarbons in European background aerosols. » Determination of microbial carbon sources in petroleum contaminated sediments using molecular 14C analysis. » Isotopic constraints on the fate of petroleum residues sequestered in salt marsh sediments. » Molecular and isotopic identification of PAH sources in a highly industrialized urban estuary. » Two abundant bioaccumulated halogenated compounds are natural products. » Vapour pressures, aqueous solubilities, Henry’s Law constants, and octanol/water partition coefficients of a series of mixed halogenated dimethyl bipyrroles. » Oil in our coastal backyard. » Radiocarbon apportionment of fossil versus biofuel combustion sources of polycyclic aromatic hydrocarbons in the Stockholm metropolitan area. » Radiocarbon evidence for a naturally-produced, bioaccumulating halogenated organic compound. » Invariant chlorine isotopic signatures during microbial PCB reductive dechlorination. » Innovative methods for determining alkenone unsaturation ratios. » Using radiocarbon to apportion sources of polycyclic aromatic hydrocarbons in household soot. » A comparative analysis of the alkanes of Yaka, Prilep, Otlja tobaccos. » Naturally-produced halogenated dimethyl bipyrroles bind to the aryl hydrocarbon receptor and induce cytochrome P4501A and porphyrin accumulation in chicken embryo hepatocytes. » Resolving the unresolved complex mixture in petroleum-contaminated sediments. » n-Alkanes and fatty acids of Hypericum perforatum, Hypericum maculatum and Hypericum olympicum. » A high-resolution record of pyrogenic polycyclic aromatic hydrocarbon deposition during the 20th century. » A chlorine isotope effect for enzyme-catalyzed chlorination. » The West Falmouth oil spill after thirty years: The persistence of petroleum hydrocarbons in marsh sediments. » Composition, age, provenance of organic matter in N.W. African dust over the Atlantic Ocean. » A critical evaluation of interlaboratory data on total, elemental, and isotopic carbon in the carbonaceous particle reference material, NIST SRM 1649a. » GC×GC: A new analytical tool for environmental forensics. » Stable chlorine intramolecular kinetic isotope effects from the abiotic dehydrochlorination of DDT. » Radiocarbon content of synthetic and natural semi-volatile halogenated organic compounds. » Radiocarbon as a tool to apportion sources of polycyclic aromatic hydrocarbons and black carbon in environmental samples. » Stable chlorine and carbon isotopic compositions of selected semi-volatile organochlorine compounds. » Evaluation of a protocol for the quantification of black carbon in sediments, soils, and aquatic sediments. » The absence and application of stable carbon isotopic fractionation during the reductive dechlorination of polychlorinated biphenyls. » Identification of a novel alkenone in Black Sea sediments. » The North Cape oil spill: Hydrocarbons in Rhode Island coastal waters and Point Judith Pond. » Even carbon number predominance of plant wax n-alkanes: a correction. » Stable chlorine isotopic compositions of Aroclors and Aroclor-contaminated sediments. » Free and bound benzotriazoles in marine and freshwater sediments. » The effects of micelles on electron-transfer and proton-transfer fluorescence quenching reactions. » GC-MS analysis of total petroleum hydrocarbons and polycyclic aromatic hydrocarbons after the North Cape oil spill. » Environmental chemistry of benzothiazoles derived from rubber. Zdenek, Z., Reddy, C.M., Teuten, E.L., Xu, L. McNichol, A.P., and Gustafsson, Ö. , Evaluation of gas chromatographic isotope fractionation and process contamination by carbon in compound- specific radiocarbon analysis. , Analytical Chemistry, 2007; v79, 2042-2049. The relevance of both modern and fossil carbon contamination as well as isotope fractionation during preparative gas chromatography for compound-specific radiocarbon analysis (CSRA) was evaluated. Two independent laboratories investigated the influence of modern carbon contamination in the sample cleanup procedure and preparative capillary gas chromatography (pcGC) of a radiocarbon-dead 3,3',4,4',5,5'-hexachlorobiphenyl (PCB 169) reference. The isolated samples were analyzed for their 14C/12C ratio by accelerator mass spectrometry. Sample 14C values of -996 ± 20 and -985 ± 20” agreed with a 14C of -995 ± 20” for the unprocessed PCB 169, suggesting that no significant contamination by nonfossil carbon was introduced during the sample preparation process at either laboratory. A reference compound containing a modern 14C/12C ratio (vanillin) was employed to evaluate process contamination from fossil C. No negative bias due to fossil C was observed (sample 14C value of 165 ± 20” agreed with 14C of 155 ± 12” for the unprocessed vanillin). The extent of isotopic fractionation that can be induced during pcGC was evaluated by partially collecting the vanillin model compound of modern 14C/12C abundance. A significant change in the 13C and 14C values was observed when only parts of the eluting peak were collected (13C values ranged from -15.75 to -49.91” and 14C values from -82.4 to +4.71”). 14C values, which are normalized to a 13C of -25”, did not deviate significantly (-58.9 to -5.8”, considering the uncertainty of ~ ±20”). This means that normalization of radiocarbon results to a 13C of -25”, normally performed to remove effects of environmental isotope fractionation on 14C-based age determinations, also cor-rects sufficiently for putative isotopic fractionation that may occur during pcGC isolation of individual compounds for CSRA.

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