Pollution Wrecks Havoc on the Oceans’ Animals and Plants
Human beings discharge hundreds of thousands of tons of waste into the oceans every day. This pollution takes the form of raw and treated sewage, garbage, industrial wastes, deadly chemicals and heavy metals, radioactive waste, and oil. Each kind of waste can create its own type of danger. The heavy (or trace) metals (Cd, Cs, Pb, Cu, Zn, Co, Ni, Fe, Mn, and Hg) are by products of manufacturing, which enter the marine environment through ocean and wind currents, sewage, and runoff from land, and through geochemical cycling from sediments into the marine food chain. Trace metals are by products of the manufacturing and ocean dumping of a host of items including automobiles, airplanes, batteries, and arms (e.g., explosives, nerve gases, and biological warfare agents). Similarly, plastics of all kinds are well known to entangle marine organisms and also may be ingested as plastic pellets, causing marine life to obtain full stomachs, but no nutrition. Nearly all are bio-concentrated in the oceanic food chain.
In the greater Caribbean, large manufacturing centers occur in Venezuela, Colombia, Mexico, the U.S., Cuba, Puerto Rico, and Jamaica, and their wastes find their way into the coastal waters of Latin America. Cu, Zn, Mn, and Fe are important in primary productivity but, except for Cu, which is important for respiration in crustaceans. None of these heavy metals is used by marine animals, such as whales, corals, and billfish, and nearly all cause pollution and are considered detrimental to marine plants, such as algae, phytoplankton and seaweed.
The biggest problem the whales are facing today is pollution. With the decline of the whale populations, the oceans are slowly dying. Whales, who for centuries lived in the St. Lawrence region of the Atlantic Ocean, had to migrate due to the polluted water. Curious as to why the population of St. Lawrence belugas had remained low despite protective measures, studies were conducted over 15 years. Researchers recorded 179 deaths and examined 73 carcasses at the Faculty of Veterinary Medicine of the University of Montreal. Subsequent analyses confirmed that the entire population was highly contaminated with an array of chemicals. The pathological observations were stunning. Forty percent of the animals bore tumors, 14 of which were cancerous, representing more than half of all malignancies ever reported in cetaceans. There was also a high incidence of stomach ulcers, including three cases of perforated ulcers, a condition never before documented in whales. Forty-five percent of the females produced only small amounts of milk because of infection, necrosis or tumors in their mammary glands. Lesions of the thyroid and adrenal glands were common. And many animals seemed to suffer from immunity: a disproportionate number had opportunistic bacterial and protozoan infections.
A whale’s immune system can be contaminated by polychlorinated biphenyls, or PCBs. One widely used method of polychlorinated biphenyls or PCB disposal, incineration, releases PCBs into the atmosphere, where they are then easily spread. The compound has been found from isolated Rocky Mountain lakes to remote areas in the Arctic. Killer whales accumulate great quantities of PCBs because their primary food sources – salmon and, in some cases, seals – are high on the food chain and long-lived. The high levels of PCBs that build up in the prey are passed along to the whale. The whales have large fat reserves where PCBs can be stored, and since killer whales can live as long as 80 years, the toxic levels keep growing over a lifetime. Algal toxins have been implicated in some mortalities of humpback whales on the Atlantic coast of North America. The effects of these toxins include reduced physiological fitness and thus increased susceptibility to secondary bacterial infections that are the immediate cause of death. For a poison like PCBs, proper disposal is a vital step toward ensuring the health of whales.
The oceans’ plants are prey to pollution. The smallest plants in the ocean are plankton, known as phytoplankton. They are the predominant forms of life in the ocean. Types of phytoplankton are the single-celled plants, or diatoms, which constitute more than half of the plant life in the ocean. Algae is comprised of major plants in the ocean. Some are microscopic, but others, such as the kelp, often grow to several hundred feet in length. Phytoplankton and algae are primary producers in the food chain of fish.
Seaweeds are among the oceans’ most valuable living resources. They usually grow in the high intertidal regions in clear waters less than 300 feet deep. The greatest value of seaweeds in the U.S. has come from the chemical and industrial products derived from them-agar, algin and carrageenin used in ice cream and candy and mannitol used in medicinal drugs. Herbicides are widely used to kill and control weeds, and range from relatively non-toxic, naturally occurring components such as pyrethrins and arsenates, to extremely complex, long-lasting man-made compounds such as 2,4-D and 2,4,5-T. These herbicides kill algae, phytoplankton and seaweed
Eutrophication along with thermal pollution is major problem with water supplies. Eutrophication is the addition of nutrients to water supplies. This is carried out by run-off from farmlands. This addition of nutrients is causing the algae and phytoplankton populations to increase dramatically. If enough of the algae and phytoplankton decay, the ocean could possibly be striped of all its oxygen. If this were to occur, all the living creatures would eventually suffocate and die. If these creatures were to die then the animals dependent upon them would soon die as well.
Thermal pollution can also have the same affect of eutrophication. When warm water is added to a water system, the algae, seaweed and phytoplankton population increases. This causes the same rate of oxygen level decline. However, when colder water is added to a water system, the effect is a little different with the same end result. When cold water is added, the algae, seaweed, and phytoplankton, which is not used to the sudden change, are killed. This speeds the decaying process and again depletes the oxygen levels, thus killing some marine organisms. In aquatic systems, when the pH of water approaches six (neutral is seven), some plankton begin to disappear. As pH approaches five, major changes in plankton occur and more acid-sensitive fish populations begin to die. Below pH five, most water life is dead, mosses take over shore areas and terrestrial animals dependent on aquatic systems also suffer.
Most animals and plants affected by pollution could begin to recover if governments pursued policies to protect and revive them. Currently, only a few regional programs and laws exist. The Federal Water Pollution Control Act, known as the Clean Water Act (CWA) has jurisdiction over U.S. waters, including the coastal sea to the three-mile limit. It was passed in 1972 and has undergone modification and expansion. Congress established its primary purpose as the “restoration and maintenance of the chemical, physical, and biological integrity of the national waters” (Federal Water Pollution Control Act PL 92-500). Governments need to increase their efforts in stopping pollution by addressing the more basic issue of controlling land use and coastal development to prevent pollution of the oceans’ animal and plant life. To avoid continued animal and plant decline in the decades ahead, countries need to pursue two areas of policy. One is the management and protection of the oceans’ animals and plants; the other is pollution prevention.
The creation of an ecosociety is the solution to pollution. An ecosociety is sought after by environmental activists and groups such as Greenpeace. An ecosociety can be achieved in the following ways: conservation of resources, decrease in material production, and decrease in industrial output. By concentrating on protecting the oceans and other ecosystems, it may be possible for people to change from a consumer to a conserved society, a society in which we live in harmony with nature, not in dominance over it.
References
Beland, P. et al. “Toxic Compounds and Health and Reproductive Effects in St. Lawrence Beluga Whales.” Journal of Great Lakes Research 19 (1993): 766-775.
de Sylva, D. P. and P.R. Breder. “Reproduction, Gonad Histology, and Spawning Cycles of North Atlantic Billfish (Istiophoridae).” Bulletin Marine Science 60 (1997): 668-697.
Federal Water Pollution Control Act of 1972 and Amendments, PL 92-500 (The Clean Water Act).
Hayteas, D. L.; Duffield, D. A. “High Levels of PCB and p,pprime-DDE Found in the Blubber of Killer Whales (Orcinus orca).” Marine Pollution Bulletin 40 (2000): 559-561.
Leipold, G. A New Environment for Greenpeace. Foreign Policy (Nov./Dec. 2001) p. 66-7.
Levitus, J. I. Antonov, T. P. Boyer, and C. Stephens, “Warming of the World
Ocean.” Science 287 (2000): 2,225-29.
Northoff, E. “The Suffocating Black Sea.” World Press Review 42 (Aug. 1995): 38
