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Download fileNewly Identified DDT-Related Compounds Accumulating in Southern California Bottlenose Dolphins
journal contribution
posted on 2016-10-14, 00:00 authored by Susan
A. Mackintosh, Nathan
G. Dodder, Nellie J. Shaul, Lihini I. Aluwihare, Keith A. Maruya, Susan
J. Chivers, Kerri Danil, David W. Weller, Eunha HohNontargeted
GC×GC-TOF/MS analysis of blubber from 8 common
bottlenose dolphins (Tursiops truncatus) inhabiting
the Southern California Bight was performed to identify novel, bioaccumulative
DDT-related compounds and to determine their abundance relative to
the commonly studied DDT-related compounds. We identified 45 bioaccumulative
DDT-related compounds of which the majority (80%) is not typically
monitored in environmental media. Identified compounds include transformation
products, technical mixture impurities such as tris(chlorophenyl)methane
(TCPM), the presumed TCPM metabolite tris(chlorophenyl)methanol (TCPMOH),
and structurally related compounds with unknown sources, such as hexa-
to octachlorinated diphenylethene. To investigate impurities in pesticide
mixtures as possible sources of these compounds, we analyzed technical
DDT, the primary source of historical contamination in the region,
and technical Dicofol, a current use pesticide that contains DDT-related
compounds. The technical mixtures contained only 33% of the compounds
identified in the blubber, suggesting that transformation products
contribute to the majority of the load of DDT-related contaminants
in these sentinels of ocean health. Quantitative analysis revealed
that TCPM was the second most abundant compound class detected in
the blubber, following DDE, and TCPMOH loads were greater than DDT.
QSPR estimates verified 4,4′,4″-TCPM and 4,4′4,″-TCPMOH
are persistent and bioaccumulative.