Environmental Engineering Reference
In-Depth Information
Garbage in the Ocean
Most of the trash in the ocean stems from human activities at the shore-
line, particularly recreational activities and smoking. Each year the
Washington-based Ocean Conservancy reports the results of a world-
wide systematic collection of trash found on beaches, the most recent
report in 2010. Along the North American coastline, 55 percent of the
beach trash stemmed from shoreline and recreational activities, 37
percent from smoking-related activities, 5 percent from fi shing and
boating activities, 1 percent was medical and personal hygiene materials,
and 2 percent was from dumping.
27
Cigarette butts were the most
common item found (2.2 million); second were 1.1 million plastic bags.
Many millions of tons of trash are present in the oceans, a major
contributor to the death of sea life. Experts estimate that hundreds of
thousands, and perhaps millions, of animals are killed each year by the
artifi cial debris. The Ocean Conservancy reported fi nding 336 animals
entangled or trapped in marine debris, with fi shing-related items account-
ing for 65 percent of the cases where animals were trapped. Birds were
the most commonly affected (41 percent), with fi sh (26 percent) and
invertebrates (16 percent) second and third, respectively. Animals choke
or become poisoned when they eat trash and drown when they become
entangled in bags, ropes, and old fi shing lines.
International shipping regulations prohibit the dumping of plastics
and metal containers at sea, but it is diffi cult to enforce such rules.
Inspectors cannot be on every ship, or even on very many of them. No
one checks when a boat comes into a harbor whether the amount of
garbage onboard is consistent with the size and occupancy of the boat
or the length of time it has been at sea or, indeed, whether it has any
garbage on board at all. But it is suspicious that there are fi ve garbage
debris fi elds, composed 90 percent of plastic, fl oating in the Pacifi c
Ocean, one of which is twice the size of Texas.
28
The garbage patch
doubles in size every decade.
