DDT, Chlordane, Toxaphene and PCB Residues in Newport Bay and Watershed: Assessment of Hazard to Wildlife and Human Health - Reviews of Environmental Contamination and Toxicology - page 78

Das et al. ( 2006 ) pointed out that even though DDT levels in blubber correlated with
thyroid fi brosis in harbor porpoises from northern Europe, this type of association
was insuffi cient to establish a cause-effect relationship. DDT levels (lipid weight
basis) were highest (viz., 1,481-2,292 ppb) in the more industrialized areas and
were lowest at 1,122 ppb in the less industrialized Icelandic coast.
Siebert et al. ( 2011 ) found no correlation between stress hormones and DDT
levels in blood collected in 1997-2002 from free-ranging and captive harbor por-
poises ( Phocoena phocoena ) from the North and Baltic Seas. Geometric mean DDT
levels in blood ranged from 0.2 to 8.2 ppm on a lipid weight basis. Weijs et al. ( 2010 )
reported a decline in DDT in tissues of harbor porpoises in the southern North Sea
during the period 1990-2008.
Fair et al. ( 2010 ) reported levels of DDT (lipid weight basis) in blubber biopsies
taken from bottlenose dolphins in 2003-2005 along the southeastern US coast.
Adult males were highest at a geometric mean level of 29 ppm for Charleston, South
Carolina. At the same location, adult females were lowest at 3.0 ppm with juvenile
dolphins intermediate at 14.7 ppm. Litz et al. ( 2007 ) measured DDT in dolphin
blubber biopsies taken in Biscayne Bay, Florida in 2002-2004. The geometric mean
level in adult males and juveniles was 2.98 ppm, whereas the geometric mean level
in adult females was lowest at 0.097 ppm.
Lailson-Brito et al. ( 2011 ) reported DDT levels (lipid weight basis) of
264-5,811 ppb in blubber of franciscana dolphins stranded along the Brazilian
coast. In a follow-up study, Lailson-Brito et al. ( 2012 ) measured DDT levels in
blubber from four species of dolphins. Much higher p , p -DDE ratios

were measured in blubber from Fraser's dolphins that feed in deep open water,
where slower breakdown of p , p

′ -DDT/ p , p ′

-DDE would be expected. The blubber
of Fraser's dolphins had relatively low residue levels of 0.99 ppm DDT. Higher
levels of DDT at 5.0 ppm, 26.4 ppm and 2.4 ppm were measured in bottlenose,
rough-toothed and long-beaked common dolphins, respectively, that inhabit estua-
rine and coastal waters that are more contaminated from DDT agricultural use.
Law et al. ( 2013 ) reported DDT levels in blubber from 43 female short-beaked
common dolphins ( Delphinus delphis ) bycaught in fi sheries during the period
1992-2006 off the southwest coast of the UK. Levels ranged from 0.2 to 16.1 ppm
on a lipid weight basis. DDT levels declined during the period of investigation
although the trend was not statistically signifi cant.
Stockin et al. ( 2007 ) reported DDT levels in blubber from common dolphins in
Hauraki Gulf, New Zealand from 1999 to 2005. Levels ranged from 17 to 337 ppb
in females and 654-4,430 in males. In follow-up studies, Stockin et al. ( 2010 )
reported on levels of DDT in Hector's dolphin ( Cephalorhynchus hectori hectori )
and Maui's dolphin ( Cephalorhynchus hectori maui ) from 1997 to 2009 from all
parts of New Zealand. DDT in blubber of females ranged from 94 to 8,210 ppb with
a mean of 1,358 ppb, whereas DDT in male blubber ranged from 252 to 57,390 ppb
with a mean of 12,400 ppb. DDT residues in individual dolphins refl ected the
proximity of their habitat to agricultural and industrial releases of DDT.
Wu et al. ( 2013 ) reported levels of DDT ranging from 0.845 to 179 ppm (with a mean
of 64.2 ppm) in blubber from Indo-Pacifi c humpback dolphins ( Sousa chinensis )

′ -DDT to p , p ′