Yazar "Jantunen, L. M.M." seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Contamination of Soil by Obsolete Pesticide Stockpiles: A Case Study of Derince Province, Turkey
    (Springer, 2024) Kurt-Karakus, Perihan Binnur; Odabaşı, Mustafa; Birgul, Askin; Yaman, Barış; Gunel, Ersan; Dumanoğlu, Yetkin; Jantunen, L. M.M.
    The areal distributions of the soil organochlorine pesticide (OCP) levels were investigated at adjacent and surrounding sites of the obsolete pesticide stockpile warehouse in Kocaeli, Türkiye. OCP levels in soil at neighboring sampling locations (positioned at 0.4 to 3 km from the stockpile) varied from 0.4 to 9 µg/kg and 4.2 to 2226 µg/kg (dry weight) for ?HCHs and ?DDXs, respectively. Levels at adjacent locations (positioned within 20 m from the stockpile) were considerably higher, varying from 74 to 39,619 µg/kg and 1592 to 30,419 µg/kg for ?HCHs and ?DDXs, respectively. Levels of OCPs dropped abruptly with the horizontal distance from the stockpile and had different transect profiles. The enantiomer fractions (EFs) near the stockpile range from 0.494 to 0.521, 0.454 to 0.515, and 0.483 to 0.533 for ?-HCH, o,p?-DDT, and o,p?-DDD, respectively. These near-racemic EFs suggested that observed soil OCP levels were mainly influenced by recent emissions from the stockpile. A comparison of OCP compositions observed in the soil at the present study with the technical HCHs and DDTs revealed that the material in the stockpile primarily contains byproducts that were discarded during DDT and Lindane production at the adjacent plant instead of their technical mixtures. © 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
  • Küçük Resim Yok
    Öğe
    Is there still "new" DDT in North America? An investigation using proportions of DDT compounds
    (American Chemical Society service@acs.org, 2013) Bidleman, T. F.; Kurt-Karakus, Perihan Binnur; Wong, Fiona; Alegria, Henry A.; Jantunen, L. M.M.; Hung, Hayley
    Usage of DDT ceased over four decades ago in Canada and the United States, and since 2000 in Mexico. Potential sources in the North American atmosphere today include emissions of legacy residues from soils and long-range transport from other countries where DDT is still used or recently banned. Distinction of source types is investigated here using proportions of p,p?-DDT, o,p?-DDT, p,p?-DDE and p,p?-DDD. The relative volatilization of DDT compounds can be accurately described by their subcooled liquid vapor pressures (PL); e.g., (p,p?-DDT/p,p?-DDE)AIR = (p,p?-DDT/p, p?-DDE)SOIL x PL, DDT/PL,DDE. Using this model, the expected proportions in air due to volatilization from technical DDT and from soils in Canada, the U.S.A. and Mexico were estimated and expressed as the fractions FDDTE = p,p?-DDT/(p,p?-DDT + p,p?-DDE), FDDTO = p,p?-DDT/(p, p?-DDT + o,p?-DDT), and FDDTD = p,p?-DDT/(p,p?-DDT + p,p?-DDD). FDDTE, FDDTO and FDDTD predicted from soil emissions were compared to compound fractions in ambient air sampled at the Integrated Atmospheric Deposition Network (IADN) of stations on the Great Lakes between Canada and the U.S.A., and at arctic monitoring stations. FDDTE in air at IADN stations on lakes Erie, Ontario, Michigan and Huron were lower than in technical DDT vapor. This is consistent with emissions of aged residues from agricultural land and urban centers near these lakes. By comparison, FDDTE values were higher at stations on Lake Superior where atmospheric DDT is likely due to long-range transport rather than regional soil emissions. FDDTE increased from the early 1990s to 2005 at the Lake Superior stations and at the Canadian arctic station Alert between 2002-2005, whereas a significant decline in FDDTE was observed at the Norwegian arctic station Zeppelin Mountain. The mean FDDTO in air at IADN stations were consistent with either soil emissions or technical DDT composition, but annual values showed significant downward trends at two Canadian stations, and also decreased with time at Zeppelin Mountain (but not at Alert). These trends might signify contribution from "dicofol-type" DDT sources, which have a lower FDDTO than technical DDT or soil emissions, or preferential degradation of p,p?-DDT vs. o,p?-DDT over time. FDDTD in air at IADN stations were lower than in technical DDT vapor, showing the influence of soil sources. The enantiomer proportions of the chiral compounds o,p?-DDT and o,p?-DDD were nonracemic in some soils and ambient air, but enantiospecific analysis has not been done for IADN air samples. It is suggested that isomer, parent/metabolite and enantiomer composition information be incorporated into air monitoring programs to help identify sources. © 2013 American Chemical Society.