2 research outputs found
Facilitated Leaching of Additive-Derived PBDEs from Plastic by Seabirds’ Stomach Oil and Accumulation in Tissues
Our
previous study suggested the transfer of polybrominated diphenyl
ether (PBDE) flame retardants from ingested plastics to seabirds’
tissues. To understand how the PBDEs are transferred, we studied leaching
from plastics into digestive fluids. We hypothesized that stomach
oil, which is present in the digestive tract of birds in the order
Procellariiformes, acts as an organic solvent, facilitating the leaching
of hydrophobic chemicals. Pieces of plastic compounded with deca-BDE
were soaked in several leaching solutions. Trace amounts were leached
into distilled water, seawater, and acidic pepsin solution. In contrast,
over 20 times as much material was leached into stomach oil, and over
50 times as much into fish oil (a major component of stomach oil).
Analysis of abdominal adipose, liver tissue, and ingested plastics
from 18 wild seabirds collected from the North Pacific Ocean showed
the occurrence of deca-BDE or hexa-BDEs in both the tissues and the
ingested plastics in three of the birds, suggesting transfer from
the plastic to the tissues. In birds with BDE209 in their tissues,
the dominance of BDE207 over other nona-BDE isomers suggested biological
debromination at the meta position. Model calculation of PBDE exposure
to birds based on the results of the leaching experiments combined
with field observations suggested the dominance of plastic-mediated
internal exposure to BDE209 over exposure via prey
Contaminants in Tracked Seabirds Showing Regional Patterns of Marine Pollution
Ocean-scale
monitoring of pollution is challenging. Seabirds are useful indicators
because they travel over a broad foraging range. Nevertheless, this
coarse spatial resolution is not fine enough to discriminate pollution
in a finer scale. Previous studies have demonstrated that pollution
levels are higher in the Sea of Japan and South and East China Seas
than the Northen Pacific Ocean. To test these findings in a wide-ranging
animal, we tracked streaked shearwaters
(<i>Calonectris leucomelas</i>) from four islands in Japan
using global positioning system (GPS) and measured persistent organic pollutants (POPs) in the oil of their
preen glands. The POPs did not change during 6 to 21 days when birds
from Awashima were foraging only in the Sea of Japan, while it increased
when they crossed to the Pacific through the Tsugaru Strait and foraged
along the eastern coast of Hokkaido where industrial cities occur.
These results indicate that POPs in the oil reflect relatively short-term
exposure. Concentrations of POPs displayed greater variation among
regions. Total polychlorinated biphenyls were highest in birds foraging
in a small area of the semiclosed Seto Inland Sea surrounded by urbanized
coast, <i>p,p</i>′-dichlorodiphenyltrichloroethane
(DDT) was highest in birds foraging in the East China Sea, and total
hexachlorocyclohexanes were highest in birds foraging in the Sea of
Japan. All were lowest in birds foraging in the Pacific. This distribution
of POPs concentration partly agrees with previous findings based on
mussels, fish, and seawater and possibly reflects the mobility and
emission sources of each type of POP. These results highlight the
importance of information on the foraging area of highly mobile top
predators to make them more effective monitors of regional marine
pollution