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Ocean Pollution: Causes and Effects

by Sekar Puspa

Before we discuss ocean pollution, at first we should define what pollution is. The definition will give us the scopes and aspect of the subject matter. We can agree and disagree about it, so we will refer to the context of the definition on pollution and related concepts at first.

Various national and international organizations have defined pollution. In this matter, we refer to the definition of United Nations on pollution. The worldwide organization of nations defines pollution as:

(1) Presence of substances and heat in environmental media (air, water, land) whose nature, location, or quantity produces undesirable environmental effects

(2) Activity that generates pollutants. Pollution relates to substance and heat in a kind of pollutants with adverse effects to environment.

In definition, environment itself covers “sum total of water, air and land interrelationships among themselves. As well as with other living organisms, the human being, and property.” Environment has the scope of physical and biological environment establishing an ecosystem.

Moreover, A.G. Tansley (1935) defines an ecosystem is the ecological unit consisting of biotic factors (living) and abiotic factors (non-living) in a specific area. In a kind of abiotic and biotic factors, natural ecosystem covers terrestrial and aquatic ecosystem. The terrestrial ecosystem covers forest and grassland ecosystem, and the aquatic ecosystem includes marine and fresh water ecosystem.


The abiotic factors comprise some components, such as physical and chemical ones. While physical components mostly include sun, water, temperature and soil, the chemical ones include among others protein, carbohydrate, fat. Moreover, biotic components base on each function in the ecosystem, such as producers and consumers. Out of the abiotic and biotic factors, there are decomposes consisting of microorganisms that decompose living creatures and plants and convert them from complex organic compounds to simpler ones and then recycle all the nutrients back. Therefore, in implicit we see that the ecosystem establishes nutrient cycling and food chain.

From the above explanation, we see that pollutants influence air, land and water ecosystem. As we impair an ecosystem, it is possible that the pollutants deteriorate nutrient cycling and food chain in the ecosystem. Whether there are pollutants from natural pollution, the tremendous effects to environment  is human-made pollution. These results from human activities in a kind of agriculture, industries, mining and transportation. Therefore, reducing ocean pollution require us to know causes, effect and prevention of pollution to water bodies particularly related to ocean issues.

Water Pollution

Water pollution relates to pollutants discharged into water, and it makes water quality worse than before. Total human population in the world amounts to 7 million people, and the number can absolutely deteriorate water quality. The worse water quality gets when there are many pollutants entered into water ecosystem.

As long as we know, water pollutants include pathogens, inorganic compounds, organic material and macroscopic pollutants (trash-paper, plastic, food waste, small waterborne plastic pellets, pieces of wood, metals and shipwrecks). The pollutants deteriorate water bodies from stream, groundwater to ocean. The polluted water will make plants, animals and men sick or die. Environmental scientists make classification on the water pollutants. It is intended to have better comprehension on the subject matter. At least there are six classes of water pollutant.


Firstly, disease-causing agents are the causes of millions of people around the world sick or die. Bacteria, viruses, protozoa, parasitic worms as well as dino-flagellates and diatoms come from domestic sewage and animal waste. Drinking, swimming in or washing clothes in the polluted water make people suffering malaria, diarrhea and guinea worm. They frequently encounter it when they live in polluted environment.

Secondly, oxygen-demanding wastes occur when bacteria from wastes or nutrients from human, domestic or wildlife in polluted water require oxygen in great number for its growth. As a result, oxygen supply is limited for all organism with their high metabolic rates, like fish, filter feeder as well as higher plants. The polluted water changes water bodies into lifeless zones. The situation destroys the nutrient cycling and food chain in the polluted ecosystem.

The third pollutant agents are water-soluble inorganic chemicals. These are from acids, salts and toxic metals. The metals are among others mercury, lead and dioxins. If the pollutant agents are in high level, the polluted water is unfit to drink, dangerous for fish and aquatic life. If used as irrigation water, it can decrease crop yields. Moreover, if it is exposed to the water, metals will be easily corrosive. Industries are the parties who are responsible to drain the chemical waste into water.

The fourth pollutant agents are nutrients. Nutrients known as water-soluble nitrates and phosphates are chemical elements required for the growth of all living organisms from plants to animals. If the nutrients are excessive in water bodies, these become water pollutants. These can cause algae and other water plants to grow excessively. The pollutants will deplete oxygen in the water bodies.

The fifth pollutant agents are organic compounds. The compound has long bonds in a kind of carbon. When they depend on functional groups being determinant of toxicity, they have long effect. Oil, plastics, pesticides, detergents, polychlorinated biphenyls (PCB), insecticides, hydrocarbons are organic compound harmful in water bodies. The organic compounds are human made products introduced since the last century.

Suspended sediments are the sixth pollutant agents in water bodies. When we pick up a bottle of river water with suspended sediment, we can see suspended sediment in the bottle bottom. Calcium, nitrogen, magnesium and phosphorus run off the land into water bodies. As pesticides from agricultural field run into streams when it rains. It will deplete light absorption in water bodies for turbidity and cloudiness. For water animals, it can clog fish gills. The bottom of water bodies will undergo what it is called siltation.

The last pollutant agents are water-soluble radioactive compounds. Information on the pollutant agents are rare. It only states that it occurs when the compounds are discharged without proper treatment, so they are very dangerous water pollutants. The effects include cancer, birth defects and genetic damage.

Pollution in Oceans

In the 1969 United Nations report, it defines ocean pollution as the introduction by man, directly or indirectly, of substances or energy into the marine environment (including estuaries) resulting in such deleterious effects as harm to living resources, hazards to human health, hindrance to marine activities, including fishing, impairment of quality for use of sea water and reduction of amenities. Despite there are natural sources, humans are the biggest responsible agent for ocean pollution. They have introduced pollutant agents to marine environment and the effects to marine environment and activities as well as humans themselves.

Humans do a variety of activities that trigger ocean pollution. These include land-based sources of ocean pollution, ballast water, industries, military activities. The activities are more beneficial for humans themselves than marine environment. However, marine environment tends to encounter adverse effects to humans’ activities, such as ocean pollution. As follows we see some of the activities that trigger ocean pollution.

Land-based sources of water pollution is a conflict issue among coastal countries and some maritime powers in the world. The first issue relates to water pollution from land-based sources. It damages the waters of neighboring countries and/or their coastline. The second issue relate to shipping traffic through waterways in a region which borders to several coastal countries. The disposal of solid wastes and bastal water from ships and other offshore sources are factors that coastal countries complain. On the contrary, many maritime powers refuse the complaint. However, in future these become a severe conflict issue particularly in the region with the busiest waterway in the world.

Ballast water discharge from ships introduces alien marine species from plants, animals, bacteria to viruses, microbes, small invertebrates, eggs, cysts and larvae in the arrival port. For example, the Asian phyto-plankton algae Odontella (Biddulphia sinensis) was introduced in the North Sea in 1903. Ballast water becomes essential component of modern shipping operation. All ships from cruise ships, large tankers to cargo carriers are charged ballast water in a great number before the departure. The ballast water will be discharged in the arrival water. However, there is regulation on this matter, ballast water discharge is serious problem in various aspects of economy, health and ecology in the host environment.


Industries become the sources of ocean pollution as well. There are many types of pollutant agents discharged from industrial sites on land, such as petroleum, hazardous, thermal, radioactive, marine litter, synthetic or organic compounds, pesticides and mining refuse. For example, the discharge of thermal pollution can eliminate corals and other sensitive marine organisms for the differences of temperature. The ocean animals cannot adapt to the change of temperature. The industrial sources of ocean pollution deteriorate ocean ecosystem and environment in the destruction of its nutrient cycling and food chain.

Concerning radioactive sources in ocean pollution, these come from military activities. Nuclear submarines and military waste discard radioactive materials to ocean waters. It causes destructive harm to ocean life. Moreover, some organisms with concentrate radioactivity in their body enter into maritime food chain. Humans can consume them later.

Oil and mining activities can trigger ocean pollution as well. Minimata disease occurs due to severe mercury poisoning in Minimata Bay, Japan. Shellfish and fish from Minimata Bay and Shiranui Sea were eaten, and local people who consumed them suffered neurological syndrome. Minimata Bay tragedy causes feeling of afraid in Indonesia, i.e. gold mining waste discarded to Buyat Bay, North Sumatra, Indonesia.

Environmental scientists and experts consider agricultural activities are definitely the sources of ocean pollution. Nonpoint source pollution called runoff comes from agriculture activities in farm. Water runoff from farm field takes away a bulk of agricultural waste. For example, nitrogen from runoff of the agricultural waste may change into nitrite and nitrate. The oxygen depletion in ocean, nitrite and nitrate concentrate in drinking water and health problems such as methemeglobphinemia or blue baby syndrome are some effects of agricultural runoff from nitrite and nitrate compounds.

Amount of Ocean Pollution

“The ocean is basically a toilet bowl for all of our chemical pollutants and waste in general,” Chelsea Rochman, a conservation research fellow at the University of California said (Alternate, April 3, 2016). Humans have made ocean as a global trash can. Whether we are conscious of it or not, if we do not do something, ocean pollution disaster will happen in future.

Conservation activist Jacques Cousteau has ever said that water and air, the two essential fluids on which all life depends, have become global garbage cans. The statement is not excessive but fact because as over 80% of marine pollution comes from land activities. Land-based waste runs into ocean waters every year.

Causes of Ocean Pollution

1.Plastic Uses

Common human product found in ocean waters is plastic. Plastic harms environment because it takes a hundreds years to break down. It is considered as well that plastic becomes food of marine animals. Plastic ban becomes solution. Plastic is found in the breathing passages and stomachs of whales, dolphins, seals, puffin and turtles. However, we cannot dare to take the action. Green-Peace states ten percent of 100 million tones that humans produce per year is dumped into ocean. In the Great Pacific Garbage Patch, a massive dump of floating garbage in the Pacific Ocean, it is found that plastic concentration reaches seven times higher than zooplankton in the sample.

Plastic uses definitely have negative effects to ocean life. For low biodegrade rate, fish and sea mammals eat plastic in tiny pieces. Ten thousands of sea turtles and birds Plastic die for ingestion and entanglement per year. Chemical compounds from plastic are also found in fish bodies. The effects occurs when plastic enters into nutrient cycling and food chain in ocean life.

2.Oil Spills

Oil spills are liquid petroleum hydrocarbon products released into ocean waters and these are harmful for ocean plants and animals from marine birds, mammals to fish and shellfish. Oil can affect insulating ability among fur-bearing mammals and water repellency of feathers among ocean birds. It also influence coastal environment. It can kill sensitive habitats in coral reefs along coastal region. It reaches 12 percent of total oil waste in ocean waters.

3.Garbage Dumping

Ocean becomes human garbage trash. The discharge of solid waste creates the Pacific Garbage Patch with the estimated large of Texas and the Great Atlantic Garbage Patch which does not see before between Bermuda and the U.S. Virgin Islands. Two similar garbage patches will likely occur in other regions throughout the world. In the ocean conservancy report in 2015, China, Indonesia, the Philippines, Thailand and Vietnam discharge 60 percent of the plastic waste into ocean waters. It occurs because these Asian countries collect 40 percent of garbage produced every year. The remaining number is discharged to land and water bodies.


Frequently human does not care about sewage disposal. WWF Global shows that eighty percent of urban sewage discharged into the Mediterranean Sea is untreated. It does not only occur in the Mediterranean Sea but it is also in many areas in the world. The sewage disposal is from inland sanitation facilities and vessels. Eutrophication occurs for the sewage disposal. The area with full of eutrophication can create dead sea zones particularly in estuaries, bays, and marginal seas. Moreover, microorganism in the sewage disposal can contaminate waters and cause diseases in humans.

5.Factory Waste Disposal

Despite dumping of industrial, nuclear and other waste are illegal since early 1970, it still occurs everywhere until right now. It also occurs to factory waste disposal discharged to ocean waters. Cost factors become reasons behind the habits particularly industries in developing countries. Government regulations and laws are effective way to prevent the habit. The costs of factory waste disposal should be entered into the industrial activities. The pressure will stimulate industries to apply cleaner methods of waste disposal treatment, such as fuel incinerators and wastewater treatment.

6.Uses of Toxic Pesticides

Instead of killing pests and insect in agricultural fields, pesticides have negative effects on the environmental sustainability and global stability particularly ocean waters. As farmers do not know the toxicities of pesticides, they frequently use it excessively. However, the farmers’ uses of toxic pesticides ends up in water bodies. On the other hand, The toxic chemicals are persistent in ocean environment. Marine mammals can avoid absorbing the deadly toxins. As reported in the Journal Nature Ecology and Evolution, scientists discovered polychlorinated biphenyls (PCBs) and other persistent organic pollutants in a high level in ocean animals lived in deep water of the Mariana Trench in the Pacific Ocean. It was also discovered in deep water of Kermadec trench in north of New Zealand.


a.Marine Life

Effects of ocean pollution occur in all aspects of marine life. Oil spills have negative impact to ocean plants and animals, environment in water surface and deep water. For example, oil deteriorates the nesting areas and feeding grounds of ocean animals. When ocean animals clean their bodies, they may ingest oil. Oil spills can prevent sunlight and photosynthesis. If the pollutant agents are sink into deep water, ocean plants and animals living here are in danger. Their bodies contain chemical compounds for a long of period. Moreover, the toxic chemical will enter into ocean nutrient cycling and food chain. When humans consume ocean products they will be contaminated.

Moreover, the quality of marine life gets poorer from time to time. For example, Persistent Organic Pollutants persist in the environment for ten hundreds of decades. They resist environmental breakdown in a kind of biological, chemical and photolytic processes. These results in humans’ health problems. Like POP, the chemical compounds of Polybrominated diphenyl ethers (PBDEs) found in many products, such as cars, furniture fabrics. It can cause cancer in ocean animals and humans.

b.Human Life

Effects of ocean pollution influence human life. Photosynthesis occurs in oceans in the world. It produces over seventy percent of oxygen. Oceans in the world also supply 97 percent of total world water supply. For the oxygen depletion, nitrification results in over 450 dead zones in oceans in the worlds. It will reduce oxygen supply to the world. The toxic chemicals consumed together with ocean animals cause various health problems, such as the damage of nervous system and kidney. For example, mercury is a dangerous chemical compound that will trigger Parkinson’s, Alzeimer’s and hearth disease. Finally, humans may suffer stomach-aches, diarrhoea or skin rashes when they are on the beach with polluted water.

c.Ocean Animals

Ocean pollution makes ocean animals contamined. For example, it makes the beluga whales (Delphinapterus leucas) of the St. Lawrence Seaway and Estuary the “most toxic mammal” in the western hemisphere. Cancer of the proximal intestine in Orcas occurs after they are exposed to 2,4-dichlorophenoxyacetic or 2,4-D in the waters. The rate of cancer among the beluga whales from the water is higher than those from wild terrestrial or aquatic animals. Moreover, the chemical compounds of PCBs killed orcas or killer whales. The 2007 study found the PCBs contaminated Orcas in the Pacific Nortwest waters. The contaminated killer whales are vulnerable to infectious diseases, abnormal growth and reproduction process.

How We Stop Ocean Pollution

  • Recycling Process

The best way to stop ocean pollution start from you and I. Recycling should become habitual action in our home and school. We can do the recycling of plastic containers, paper, glass, cans and others. The government itself should have great concern to ocean pollution by issuing some regulations and laws on the prevention of ocean pollution. When using chemical compound in our uses, we should avoid the compounds falled into water. We are afraid these will run into ocean. The last but not the least, we should reduce plastic uses in our daily activity. At least, therefore, we become people who concern environmental issues in our life.

  • Disposal of Waste

As civilized human society in the modern world we are the major subject of preventing the disposal of waste to ocean. Rivers, lakes and estuaries where we live should clean from the disposal of waste. It also occurs to human activities in a kind of sewage, industrial waste, military waste, ships and others. The civilization meaning should treat environement in civilized way. As long we consider all human activities are civilized, therefore, these will have good effects to environment including ocean waters. Moreover, the civilized activities get support from laws and regulation in the level of world and nation level. For example, UN has issued he UN Conference on the Human Environment in June 1972 and the Inter-Governmental Conference on the Convention of the Dumping of Wastes at Sea in November 1972. The laws and regulations should be implemented in consequence.

  • Reforestation

Reforest the world! It is right way of preventing ocean pollution from land. It is the best option because ocean pollution is from the land-based sources. Reforestration program will plant trees and reduce soil erosion, flood and toxin to water bodies. The governments in the world should be the number-one initiator because they are the most powerful organization in this planet. The government should also reconsider agricultural practices. The Over-cropping and overgazing in agricultural practices should be prevented because it contradict to the reforestration because it can lead to flood and soil erosion. As a result, the program can be considered successful if the carbon cycle is under and within the manageable limits.

  • Telecommuting

Postmodern era can reduce the use of transportation mode because people are able to work from home. Their work activities get support from the sophisticated telecommunication devices, such as Internet, email, and telephone. If a majority of people can work from where they live, it will give great contributio to the reduction of air pollution and other wastes, such as oil spill from transportation vehicles. Moreover, telecommuting people will use transportation with low air pollution, such as bicycle, non fossile fuel for their vehicles.

  • The use of renewable energies

The use of renewable energies should become priority of energy in human life and their activities, such as the use in industries and transportation vehicles. Fossil fuel should be reduced. As long as renewable energies are just alternative energies, industrialists will take fossil fuel as the fuel of their industries due to cheap costs. Once again the governments should become the pioneer in this matter. They stimulate scientists to discover renewable energies with cheap costs but natural friendly.

For example, how scientists discover technology to use solar energy. It is estimated that humans only need 30% of sunlight energy for their energy demand. All this time most of sunlight is useless and it is reflected back to the space. The scientists are stimulated to discover technology that can store solar energy in long term. So, it will be used in winter or certain places without sunlight.

In conclusion, reducing ocean pollution should become our attention. A majority of people is considered to have little attention on this matter. We depend mostly on activists in this matter. As long as we have similar understanding on this matter in the level of common people, high ranking officials in the government and organization in the world level, industrialists, definitely ocean pollution can be prevented. We have known the causes, effects and prevention of pollution to water bodies, the next step is how to realize the mission of better life better earth. It is because we are definitely civilized humans who do civilized activities to environment.

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