Environmental Engineering Reference
In-Depth Information
collecting in the benthos on the organisms living there and on the marine
ecosystem, in general, remain unclear and unresearched.
The problem of plastic debris in the oceans will continue to grow in the
future with more plastics being added each year into the ecosystem. Also,
demographic patterns show preferential migration of human population to
coastal regions. Already about half of the world's population live within
200 km of a coastline and that number will double by 2025 (Creel, 2003).
The recreational use of beaches and the ocean (especially boating) is on the
increase making it even more likely that plastics and other wastes will end
up in the oceans. Once in water, plastics are dispersed in oceans worldwide;
plastic debris has even been detected in waters in Antarctica (Barnes et al.,
2010).
10.1 ORIGINS OF PLASTICS IN THE OCEAN
Plastics debris present in the oceans can be traced back to several sources:
1. Plastics derived from commercial fishing: With the entire global fleet
now using plastic gear (Butler et al., 2013; Veenstra and Churnside,
2012; Watson et al., 2006), inadvertent losses and deliberate disposal of
post-use gear at sea is an obvious source of debris. With an estimated
4.4 million fishing vessels (most in Asia) in operation, this can be a
significant source of input of plastics into the ocean. In addition to gear,
polystyrene foam (EPS) products are also disposed from vessels. EPS
(as well as some polyurethane) is used in vessel insulation, floats on
gear, baitboxes, and food service items.
2. Packaging waste from MSW and beach use: About a third of the plastics
resin produced globally ends up as plastic packaging of which less than
9% of waste in the MSW is recovered for recycling. Plastic litter on land
can be transported to the oceans via storm drain runoff. Recreational
use of beaches also results in beach litter that can be picked up by wind
and tidal movements and transported into the water (Corcoran et al.,
2009; Rosevelt et al., 2013; Ryan et al., 2009). Beach cleanup
operations help reduce the litter but there is virtually no mechanism to
collect such debris once they enter the water.
longer discard the plastic waste at sea but bring them back to the shore
for recycling.
