International Journal of Marine Science, 2016, Vol.6, No.9, 1-20
4
due to the reduced UV exposure and lower temperatures found in aquatic habitats (Gregory and Andrady, 2003).
Thick plastic items persist for decades, even when subject to direct sunlight, and survive even longer when
shielded from UV radiation under water or in sediments.
Table 1 Concentrations of Hg and Cd in marine organisms across the globe.
Organism
Region
Metal
Concentration
Reference
Mytilus galloprovincialis
Spanish coastline
Cd
0.400 – 2.00 μg g
-1
d.w.
Bartolome
et al.
, 2010
Fernandez
et al.
, 2010
Hg
50.00 – 350.00 μg g
-1
d.w.
Marmara Sea, Bosphorus
Asian and European
side
Hg
0.140–2.940 μg g
-1
d.w.
Kayhan, 2007
Cd
8.95–10.68 μg g
-1
d.w.
Adriatic Sea, Croatia Hg
8.58 μg g
-1
d.w.
Stankovic
et al.
, 2011
Mollusk
Taranto Gulf
THg
n.d. to 1.87 μg g
-1
d.w.
Spada
et al.,
2012
MHg
n.d. to 1.32 μg g
-1
d.w.
Fish
Taranto Gulf
THg
0.324 to 1.74 μg g
-1
d.w.
MHg
0.190 to 1.040 μg g
-1
d.w.
Izmir Bay,
Eastern Aegean
Hg
0.014 – 0.500 μg g
-1
wet wt.
Kucuksezgin
et al.,
2011
Cd
0.0001 – 0.010 μg g
-1
wet wt.
Adreatic sea
Hg
0.001–2.070 μg g
-1
wet wt.
Bilandzic
et al.,
2011
Cd
0.001–0.850 μg g
-1
wet wt.
Black Sea, Turkey
Hg
25.0-84.0 μg g
-1
d.w.
Black Sea, Turkey
Cd
0.180–0.350 μg g
-1
d.w.
Mendil
et al.,
2012
Persian Gulf
THg
0.0614 to 0.433 μg g
-1
d.w.
Agah
et al.,
2007
Caspian Sea
THg
0.102 to 0.108 μg g
-1
w.w.
Atlantic ocean
Hg
0.0116-0.0003 μg g
-1
w.w
Vieira
et al.,
2011
Cd
0.0019-0.015 μg g
-1
w.w
Baltic Sea
Hg
0.033 -0.121 μg g
-1
Polak-Juszczak, 2012
Harbour seal (Liver)
Alaska
Hg
1.700 – 393.00 μg g
-1
d.w.
Marino
et al.,
2011
Magellanic penguins
–feathers (
Spheniscus
magellanicus
)
Argentina
Hg
<0.0014 and 0.367 μg g
-1
d.w.
Frias
et al.,
2012
Fish and shellfish
Spain
Hg
0.0038–1.621 μg g
-1
w.w.
Calatayud
et al.,
2012
The most widely recognized problems caused by marine litter pollution are typically associated with entanglement,
ingestion, suffocation and general debilitation (Gregory, 2009). According to the UN Environment Programme,
plastic debris causes the deaths of more than a million seabirds every year, as well as more than 100,000 marine
mammals (UNESCO, 2015). About 44% of all seabird species unfortunately ingest plastic. Sea turtles ingest
plastic bags, fishing line and other plastics. A recent study revealed that about 267 species of marine organisms are
badly affected by plastic pollution in one way or the other (Moore, 2008).
Another outcome of the plastic pollution is the invasion of alien species. Plastics are capable of carrying
non-native, invasive pest species over long distances and thus increase the domain of certain marine organisms.
There is also potential danger to marine ecosystems from the accumulation of plastic debris on the sea floor. The
accumulation of such debris can inhibit gas exchange between the overlying waters and the pore waters of the
sediments, and disrupt or badly affect benthic organisms.
Given the impacts of plastic litter, considerable effort should be made to remove waste plastic and other persistent
debris from the marine environment. This removal can be conducted before it enters the sea, through litter
collection and screening waste water systems (e.g. Marais and Armitage, 2004) or, thereafter, through periodic
collections of litter from beaches (e.g. Ryan and Swanepoel 1996) or the seabed (e.g. Donohue
et al
. 2001).
However, the most efficient and cost-effective solution is an “action at source”- approach creating awareness
