The Effects of Water Pollution on Marine Life

Comprising over 70% of the Earth�s surface, water is undoubtedly the most precious natural resource that exists on our planet. Without the seemingly invaluable compound comprised of hydrogen and oxygen, life on Earth would be non-existent: it is essential for everything on our planet to grow and prosper. Although we as humans recognize this fact, we disregard it by polluting our rivers, lakes, and oceans. Subsequently, we are slowly but surely harming our planet to the point where organisms
are dying at a very alarming rate. In addition to innocent organisms dying off, our drinking water has become greatly affected as is our ability to use water for recreational purposes. In order to combat water pollution, we must understand the problems and become part of the solution.

effects of pollution on lakes

Effects of water pollution on lakes

Water pollution affects the health of the waterway, the health of the organisms living in and around the

waterway, and, eventually, the health of humans. The effects of water pollution can range from aquatic

deformities to contaminated fish to "dead" lakes.

Aquatic diseases and deformities

As virtual "canaries in a gold mine," the deteriorating health of fish and wildlife speaks volumes

about the need to clean up the Great Lakes. Heavy metals such as mercury and lead, and human-

made organic chemicals such as pesticides, biomagnify as they move up the food chain, resulting

in tumors and death for predatory animals, such as lake trout, herring gulls, and even humans.

Toxic pollutants can also alter the genetic makeup of an organism, resulting in either death or

extreme deformities. Studies have found cormorants suffering from cross-billed syndrome at

rates 42 percent times the natural occurence, while terns exhibit birth defects from dioxin, PCBs

and furan exposure at 31 times the normal levels. Other examples of deformities include large

fish tumors and three-legged frogs.

Eutrophication

Before Europeans arrived in the Great Lakes region, the Great Lakes were mainly oligotrophic

lakes, meaning they contained little plant nutrients and were continuously cool and clear due

to their immense size and depth. Oligotrophic lakes can support high levels of animal life and

receive proper amounts of nutrients, mainly phosphorous and nitrogen, from natural sources,

such as decomposing plant matter.

European settlement and industrialization changed all of that. The amount of nutrients entering

the Great Lakes has intensified greatly, mainly due to increased urbanization and agriculture,

leading to increased biological growth, or eutrophication. Under eutrophic conditions, nutrient

loading (more nutrients than the waterbody can handle) stimulates excessive plant growth, which

in turn decreases the amount of oxygen in the water and eventually kills off certain species of

animal life. Other pollution-tolerant species, such as worms and carp, grow more rapidly; thus,

the ecological balance of the lake is significantly altered.

At one time, many people believed that water was capable of diluting toxic substances to the point of

rendering them harmless. However, we have since learned that this is not the case, especially in regards

to POPs, which persist in bodies of water -- no matter how diluted they are -- and accumulate in the

food chain. The United States and Canada realized that the health of the Great Lakes could be best

achieved through cooperation, and since the 1970s both countries have been working toward a cleaner

Great Lakes system.

Although phosphorus levels in lakes Ontario and Erie have decreased by almost 80 percent since the

1970s and many regulations have been placed on toxic chemical dumping, water pollution in the Great

Lakes is still causing severe damage to aquatic ecology and to our own health and quality of life. Beaches

are consistently closed due to bacterial contamination, drinking water contamination has caused

sickness and deaths around the region, many of our fish are poisoned with chemicals, and the sediments

at the bottom of the lakes are becoming increasingly toxic.

But the Great Lakes and waterways are showing signs of improvement. Researchers attribute the

success to the cleanup of industries that had originally sent their wastes into the river, as well as better

maintenance of sewer systems and sewage treatment plants in the Cuyahoga watershed.

Why so polluted?

Water covers over 70% of the Earth’s surface and is a very important resource for people and the

environment. Water pollution affects drinking water, rivers, lakes and oceans all over the world.

This consequently harms human health and the natural environment.

Under the belief that water could dilute any substance, industries and individuals during the

18th and 19th centuries often used rivers and lakes as garbage cans. Industrial effluent, raw

sewage and animal carcasses would often be dumped into waterways, without much thought of

contamination and downstream neighbors.

This practice started changing in the 20th century as people became aware of the importance

of clean water to health. However, as more industries and people moved into the Great Lakes

region, the more the rivers and lakes became polluted. Today, pollutants enter the Great Lakes

in many different ways, but the main three entryways of pollutants are point source, nonpoint

source and atmospheric pollution.

How is water get polluted??

AGRICULTURE

To increase the amount of food produced, farmers use large amounts of chemical fertilisers and pesticides. The excess chemicals not used by the plants are washed by the rainwater into rivers, lakes and seas, polluting both surface water and underground water. In a new report, the UN Food and Agriculture Organisation (FAO) says almost 500,000 tonnes of old and unused toxic pesticides have been abandoned on sites.

INDUSTRIALISATION

Factories and industries often release poisonous chemical substances into seas, rivers or lakes, resulting in the destruction of Mother Nature. An example of industrial sea pollution happened in Japan in the 1950s. A local factory had poured waste water containing mercury into the Minamata Bay for 20 years. Tuna fish in the bay absorbed the mercury and people ate the tuna. Many children were hence borned with birth deformities, people lost their hearing ad sight and thousands eventually died.

SEA TRANSPORTATION

When ships transporting oil from one country to another get damaged en route, oil spillage occurs. One historic major disaster was the Exxon Valdez oil spill, in which an oil tanker sank off Alaska in 1989, leaking 240 000 barrels of oil into the ocean. To save cost, some ships also illegally dump unwanted oil from their engine rooms into the sea, thus polluting the oceans.

DOMESTIC ACTIVITIES

Waste products from the washing of clothes, dishes and lavatories, if untreated and discharged into the sea, promote the growth of algae which destroys marine life. Infectious diseases may also spread if sewage is not treated before it is discharged into the sea.

DUMPING

Sometimes, rubbish irresponsibly dumped into the sea. There had been cases where fishes get tangled in old fishing nets or feed on packaging styrofoam and they die.

PERCENTAGE OF WORRY ABOUT WATER POLLUTION

Water Pollution Documentary