Plastic is as common to see at the beach as seashells are, but plastic litter is more than just an aesthetic disturbance; it’s a sign that humans are treating the oceans like a garbage bin.Today, the oceans and marine life are facing the threat of permanent alteration from a number of sources of pollution, and plastic is among the most significant. Plastic accounts for 60-80% of marine garbage, and in high-density areas, reaches up to 95% (Weisman, 2007). In the middle of the North Pacific, plastic outweighs algae, six to one (Leahy, 2004).
The average American will throw away 185 pounds of plastic each year. And plastic never truly disappears. Every piece of plastic that has ever been made still exists. Even when burned, it breaks down into microscopic, toxic particles. Plastic is not a material that our planet can digest. Like diamonds, plastic is forever.
When a plastic bottle is discarded improperly, rains and waterways may sweep it into a gutter and eventually out to sea. Floating at sea, the UV radiation of the sun makes the plastic brittle. The plastic breaks up into smaller pieces from the friction of the waves.
In due course, the plastic breaks down into microplastic particles, which are fragments of plastic smaller than a grain of sand or the tip of a needle. Ocean currents sweep these microplastic particles to areas called gyres, where there are high concentrations of plastic.
Almost every marine organism is contaminated by plastic, from microscopic plankton to whales, the largest mammals on earth. Marine animals that become entangled in plastic may drown or starve. Plastic garbage may resemble food for some marine species. Turtles are known to mistake plastic bags for jellyfish. Sea birds selectively ingest specific colors of plastic, mistaking them for prey. Plastic is found in the stomachs of 85% of turtle species, 43% of seabird species, and 44% of marine mammals (Derraik, 2002).
Eating plastic can hinder the secretion of gastric enzyme (which is needed for digestion) and cause the animal to starve.Other problems resulting from ingesting plastic are reproductive failure, lowered steroid levels, and delayed ovulation. Ingested plastic also introduces toxic pollutants, such as DDT and PCBs, into the animals’ bodies. The higher up the food chain a species is, the higher the amount of pollutants it will have. Thus, the bloodstreams and tissues of humans have very high levels of harmful chemicals leached by plastics. These chemicals are even found in newborns and in breast milk.
Sound pollution is an invisible but noteworthy form of pollution in the oceans. As the oceans increasingly become used for the transport of goods, the sound environment of the oceans becomes noisier. The cacophonous environment jumbles or smothers the biosonar calls of marine animals that rely on sound for navigating, feeding, and communicating. Sonar, which is often used in military exercises, can hamper the biosonar calls of whales and may cause incorrect navigation and even stranding.
Oceanic eutrophication refers to the process during which the oceans receive surplus nutrients that encourage excessive plant growth. The runoff of fertilizers that are used in agriculture may cause phytoplankton and algae to grow in unusual and excessive numbers. These inordinately high populations of phytoplankton and algae reach the ends of their life cycles and settle onto the seabed as decomposing dead matter that consumes large amounts of oxygen during the decomposition process. The resulting lack of oxygen causes local marine animals to either suffocate or leave the area, and the lifeless area becomes a dead zone. There are now 400 dead zones globally, and this number is increasing exponentially (Diaz, 2008).
Factories, mining, chemical plants, and the burning of fossil fuels are among the causes of industrial contamination. The toxins and heavy metals resulting from these processes make their way into the oceans and are ingested by marine animals. Since many toxins are persistent, they build at increasing concentrations on their way up the food chain. For this reason, shark meat contains high levels of methyl mercury, a dangerous neurotoxin that can cause infertility and mortality rates (Sharkproject International, 2009).
HOW CAN I HELP?
- Only purchase cosmetics and cleaning products that made of natural, non-toxic ingredients.
- Carry your own water bottle, mug, utensils, and reusable bag.Imagine a water bottle filled ¼ of the way with oil. That’s how much oil was used to make the bottle! (Fox, 2012)
- Buy products that have the least amount of plastic packaging.
- Pick up plastic garbage when you see it. Plan a beach clean up for your community.
- Support organic produce or produce that is grown with non-toxic chemicals. Support companies that are environmentally conscious.
Alan Weisman, The World Without Us. 2007.
Fox, Catherine. National Geographic. “Drinking Water: Bottled or From The Tap?” 2012.
Derraik, J. The pollution of the marine environment by plastic debris. 2002. http://dx.doi.org/10.1016/S0025-326X(02)00220-5
Diaz, Robert. “Spreading Dead Zones and Consequences for Marine Ecosystems.” Science 15 August 2008: Vol. 321 no. 5891 pp. 926-929 DOI: 10.1126/science.1156401
Leahy, Stephen. Drowning in an Ocean of Plastic. 2004. http://www.culturechange.org/Petroleum&Plastics.html.
Sharkproject International. Methyl Mercury. 2009.