Pollution is a problem that directly affects ocean organisms and the natural
balance. It indirectly affects human health and resources. Oil spills,
toxic wastes and the dumping of other materials all contribute to the broad
term 'Ocean Pollution'. Because oceans cover over 70% of the surface of
the earth, water sources are the perfect carriers of pollution. Thus allowing
for pollution to spread rapidly and to go all over the world via inter-connected
the oil washes up on the shore and becomes tar-like lumps; some coat the
fur of animals (e.g. sea otters) affecting their natural heating system.
Also, some oil finds its way to other water sources (such as lakes, rivers,
and personal water supplies) causing hazardous water to be consumed. In
extreme cases, rivers, lakes and wells have been known to ignite. For example,
in 1969, the Cuyahoga River in Cleveland, Ohio ignited.
Radioactive wastes, reactor leaks, natural radioactivity, and radioactive particles which originate from the Atmospheric Testing Program from explosions of nuclear weapons are dispersed in water all over the world. The effect of these radioactive particles is currently being researched.
All of these factors allow seafood to have a chance of being hazardous to human health. For example, if a fish is contaminated with the metal Mercury (by either eating it or consuming a creature who had), birth defects and nervous system damage in humans may result. Also, Dioxin causes genetic and chromosomal mutations in marine life and is suspected of causing cancer in humans.
wastes, such as stale blood vials, hypodermic needles, and urine samples
that have been found in ocean around the U.S. are being researched to determine
if swimmers have a chance of contracting Hepatitis or AIDs from such wastes.
Other wastes have been known to cause viral and bacterial diseases such
as cholera, typhoid, dysentery, and diarrhea.
Examples of trash found in the ocean are: syringes, labratory rats, human stomach lining, Navy decontamination kits, test tubes with various substances (with radioactive markings), tampon applicators, and a wallet-sized photo of a dead communist dictator.
One of the main causes of trash finding its way to the ocean is the fact that some sewage pipes share their space with storm water drains. Rainfall (at least 1/4 of an inch), causes the sewage pipes to flood and the sewage wastes (basically anything you flush down your toilet), mingles with the storm water drain which flows unhindered to a water source.
Balloons have been known to find their way into animals such as sperm whales, blocking their digestive tracts; causing the animals to die. Plastic six-pack rings choke various animals and other waste is mistaken by animals for food. Basically any unnatural trash can be harmful to ocean life.