@article {2103,
	title = {Radiocarbon content of synthetic and natural semi-volatile halogenated organic compounds},
	journal = {Environ Pollut},
	volume = {120},
	year = {2002},
	note = {Reddy, Christopher MXu, Li
Eglinton, Timothy I
Boon, Jan P
Faulkner, D John
eng
Research Support, Non-U.S. Gov{\textquoteright}t
Research Support, U.S. Gov{\textquoteright}t, Non-P.H.S.
England
2002/10/25 04:00
Environ Pollut. 2002;120(2):163-8.
},
	month = {2002},
	pages = {163-8},
	abstract = {Some halogenated organic compounds, such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polybrominated diphenyl ethers (PBDEs), have been suggested to have natural sources but separating these compounds from their commercially synthesized counterparts is difficult. Molecular-level 14C analysis may be beneficial since most synthetic compounds are manufactured from petrochemicals (14C-free) and natural compounds should have "modern" or "contemporary" 14C levels. As a baseline study, we measured, for the first time, the 14C abundance in commercial PCB and PBDE mixtures, a number of organochlorine pesticides, as well as one natural product 2-(3{\textquoteright},5{\textquoteright}-dibromo-2{\textquoteright}-methoxyphenoxy)-3,5-dibromoanisole. The latter compound was isolated from a marine sponge and is similar in structure to a PBDE. All of the synthetic compounds were 14C-free except for the pesticide toxaphene. which had a modern 14C abundance, as did the brominated natural compound. The result for toxaphene was not surprising since it was commercially synthesized by the chlorination of camphene derived from pine trees. These results suggest that measuring the 14C content of halogenated organic compounds may be quite useful in establishing whether organic compounds encountered in the environment have natural or synthetic origins (or both) provided that any synthetic counterparts derive from petrochemical feedstock.},
	keywords = {Animals, Carbon Radioisotopes/*analysis, Environmental Pollutants/*analysis, Hydrocarbons, Halogenated/chemical synthesis/*chemistry, Insecticides/chemistry, Polychlorinated Biphenyls/chemistry, Porifera/*chemistry, Toxaphene/chemistry},
	isbn = {0269-7491 (Print)0269-7491 (Linking)
},
	url = {https://www.ncbi.nlm.nih.gov/pubmed/12395826},
	author = {Reddy, C. M. and Xu, L. and Eglinton, T. I. and Boon, J. P. and Faulkner, D. J.}
}
@article {2190,
	title = {Detecting holocene changes in thermohaline circulation},
	journal = {Proc Natl Acad Sci U S A},
	volume = {97},
	year = {2000},
	note = {Keigwin, L DBoyle, E A
eng
Research Support, U.S. Gov{\textquoteright}t, Non-P.H.S.
2000/03/04 09:00
Proc Natl Acad Sci U S A. 2000 Feb 15;97(4):1343-6.
},
	month = {Feb 15},
	pages = {1343-6},
	abstract = {Throughout the last glacial cycle, reorganizations of deep ocean water masses were coincident with rapid millennial-scale changes in climate. Climate changes have been less severe during the present interglacial, but evidence for concurrent deep ocean circulation change is ambiguous.},
	keywords = {*Climate, *Plankton, Animals, Atlantic Ocean, carbon isotopes, ice, oxygen isotopes, time},
	isbn = {0027-8424 (Print)0027-8424 (Linking)},
	doi = {10.1073/pnas.97.4.1343},
	url = {https://www.ncbi.nlm.nih.gov/pubmed/10677463},
	author = {Keigwin, L. D. and Boyle, E. A.}
}
@article {2299,
	title = {An isotopic biogeochemical study of Neoproterozoic and Early Cambrian sediments from the Centralian Superbasin, Australia},
	journal = {Geochim Cosmochim Acta},
	volume = {61},
	year = {1997},
	note = {Logan, G ASummons, R E
Hayes, J M
eng
Research Support, U.S. Gov{\textquoteright}t, Non-P.H.S.
1997/01/01 00:00
Geochim Cosmochim Acta. 1997;61(24):5391-409.
},
	month = {1997},
	pages = {5391-409},
	abstract = {Organic matter from Neoproterozoic and Early Cambrian sediments of the Amadeus and Officer basins of the Centralian Superbasin, Australia, has been studied for biomarker distributions and the carbon isotopic compositions of kerogen and individual hydrocarbons. These sediments represent both shallow and deep water marine facies in the older sections and marine and saline lacustrine carbonate deposits in the Cambrian. Hydrocarbon biomarker patterns were found to be quite consistent with the known sedimentary environments and provide valuable insights into the biogeochemical changes which accompanied the transition from a microbially-dominated ocean to the early stages of metazoan radiation. In particular, carbon isotopic data for n-alkyl and isoprenoid lipids presented here, and in earlier studies, showed a reversal in carbon isotopic ordering between the Proterozoic and Phanerozoic. By comparison with the delta 13C of kerogen, n-alkyl lipids from deep-water Proterozoic sediments were enriched in 13C and appear to be derived mainly from heterotrophs whilst open marine Phanerozoic counterparts are 13C depleted and evidently derived mainly from autotrophs. Data from the samples studied here are consistent with a model invoking a change in the redox structure of the ocean, possibly aided by the innovation of faecal pellets.},
	keywords = {Alkanes/analysis/chemistry, Animals, australia, biomarkers, carbon isotopes, Carbon/analysis/*chemistry, Cyanobacteria, Eukaryota, Feces, Fossils, Geologic Sediments/*analysis/chemistry, Hydrocarbons/analysis, NASA Discipline Exobiology, Non-NASA Center, Paleontology, phytoplankton, SEAWATER, Terpenes/analysis, Zooplankton},
	isbn = {0016-7037 (Print)0016-7037 (Linking)
},
	url = {https://www.ncbi.nlm.nih.gov/pubmed/11540731},
	author = {Logan, G. A. and Summons, R. E. and Hayes, J. M.}
}
