Synthetic Polymers, commonly known as plastics, have been present in the market since the 1950s. Plastic production then intensified due to high demands with the increase in population and thus facilitating life. Subsequently, this lead to significant plastic waste production which is not accounted to be managed in landfills or recycling facilities. Hence, these wastes have overwhelmed and spread globally until they became a permanent part of the marine environment.
Marine litter is a growing environmental concern having several consequences on marine fauna and ocean health. Experts have observed ecological threats (both severity and specificity) of entanglement-fishing related gear, balloons and plastic bags-, ingestion-plastic bags and plastic utensils-, as well as chemical contamination for three major marine taxa: seabirds, sea turtles and marine mammals. However, entanglement was rated to be slightly worse because it is more likely to be lethal.
Since plastic cannot be easily removed, given the fact that it accumulates in organisms and sediments, also persists considerably longer than on land causing its transfer to humans through the food chain. As a result, this alters humans’ health; cancers, birth defects, immune system problems, and childhood developmental issue, and lastly, ending up in ecosystem disturbances!
Humankind worked hard from the earliest times to develop materials capable of offering welfares absent in natural products. Plastic is a word derived from the Greek ????????? (plastikos) meaning “capable of being shaped or molded” and, in turn, from ??????? (plastos) meaning “molded. The initial plastic example was invented in 1855 by Alexander Parkes named as Parkesine, acknowledged today as celluloid.
However, it was until recently that plastic has been referred as a name for a category of materials called polymers; made of long chains of molecules, polymers are abound in nature. For example, Cellulose, the building up material of the cellulosic wall in plants, is a very common natural polymer.
As for the development of plastic materials, it started with the use of natural materials having plastic properties such as chewing gum and shellac. After that, it has evolved with the development of chemically modified natural materials including rubber, nitrocellulose, and collagen. Finally, the various ranges of completely synthetic materials were established.
Synthetic polymers consist of extended chains of atoms, arranged in repeating units, often significantly longer than those found in nature. The length and the patterns in which these chains are arrayed make polymers strong, lightweight, and flexible. In other words, it is what makes them so plastic. In fact, these fundamental properties adding to them man’s knowledge and abilities to create as well as manipulate them are the reason for which synthetic polymers are substantially beneficial. In particular, over the last 50 years plastics have inevitably saturated our world and changed the way we live. (Freinkel, 2011) (Leighton, 1942)
Texture, shape and color
Plastics can be rubbery or rigid of wide shape variety include sheet, rod, hex, pipe, cubes, balls, tubes, etc.
They are available in many colors and in transparent form.
Supplementary properties that make plastic superior to other materials in many applications are:
· Corrosion and Chemicals resistant
· Shock and Water resistant
· Low electrical and thermal conductivity
· High strength-to-weight ratio
· Good durability
· Easy to manufacture
· Low cost
· Low toxicity
Types and usage
There are many different types of plastics, and they can be grouped into two main polymer families:
Thermoplastics (which soften on heating and then harden again on cooling)
Thermosets (which never soften when they have been moulded)
Acrylonitrile butadiene styrene(ABS)
Polyethylene terephthalate (PET) / Polyester (PES)
Polyvinyl chloride (PVC)
Unsaturated polyester resins (UP)
Polymethyl methacrylate (PMMA)
Expanded Polystyrene (EPS)
Table 1 Types of plastics
Figure 1 Plastic classifications according to the Society of Plastic Industry (SPI)
Plastic and Marine Environment
How Is Plastic Ruining The Ocean?
For the last half century, plastic has become an integral part of our daily life. From furniture to grocery bags, from vehicle parts to toys, plastic is a mandatory element regarding our lives in different forms.
However, plastic is today considered as a material of serious destructive and harmful potential mainly due to its non-biodegradable criterion, which exacerbates the threat of persistent plastic wastes for the upcoming years. It has been estimated that people worldwide throw away almost four million tons of trash per day, of which 12.8 percent is plastic, polluting land, air and water. Consequently, plastic thrown into landfills contaminates the soil and groundwater with harmful chemicals and microorganisms, triggering immeasurable and considerable effects on marine pollution.
Just like on land, even in the oceanic areas, the effect of plastic on marine life has started to be recognized. It has been revealed that around 12.7 million tons of plastic wastes are washed into the ocean every year. According to the United Nations Environment Program estimation there could be 51 trillion micro plastic particles in the oceans by now, and by 2015; 1 ton of plastic for 3 tons of fish, while by 2050; 1 ton of plastic for 1 ton of fish. Even though part of this waste comes from land, mainly due to mismanaged waste disposal, the ships and offshore oil and gas platforms. (Mambra, 2017)
Figure 2 Plastic ocean pollution
Impact on Marine Mammals and Sea Birds
Researchers accentuate that plastic pollution is not only found in oceans but also on the shores of remote islands, and in the bellies of the Dead Sea birds and marine mammals.
In August 2006, the Marine Mammal Commission announced that the issue of debris accumulation has significant threats towards marine mammals, seabirds, turtles, fish, and crustaceans. These straightforward threats are primarily mechanical; individual animals may entangle either in loops, or openings of floating, or even submerged debris. Otherwise threats will most probably ingest plastic materials.
Figure 3 Gray whale entangled in netting
Most fish in the North Pacific ingest 12,000 to 24,000 tons of plastic each year and thus, triggering intestinal injury, death and plastic transmissions to superior fish and marine mammals through the food chain. Recently, after conducting a study in California, it was founded that around quarter of fish at markets contained plastic in their guts, as plastic microfibers.
Figure 4 Long and flat pieces of plastic are the worst for entanglement
Moreover, sea turtles can also mistake floating plastic garbage for food which explains why soft plastic, ropes, styrofoam, and monofilament lines are mainly found in their stomachs. Infact, Ingestion of plastic will most likely lead to blockage in the gut, ulceration, internal perforation and even death. Unfortunately, researches indicate that half of sea turtles worldwide have ingested plastic.
Figure 5 Albatross stomach is full with plastics products
Also, hundreds of thousands of seabirds ingest plastic at a yearly basis. This plastic ingestion will most probably permit the reduction of storage volume in the stomach, triggering birds to consume less food and ultimately starve.
For instance, almost all Laysan albatross chicks — 97.5 percent — have plastic portions in their stomachs after being fed by their parents whom had mistaken between plastic particles and food.
Figure 6 Plastic: a major reason why albatross die!
It is estimated that 60 percent of all seabird species have eaten pieces of plastic, an approximation predicted to increase to 99 percent by 2050. Based on the amount of plastic found in seabird stomachs, it can be asserted that the extent of garbage in our oceans has rapidly intensified in the past 40 years.
Furthermore, marine mammals ingest and get tangled in plastic. This can be illustrated by the fact that considerable quantities of plastic debris have been found in the habitat of endangered Hawaiian monk seals, including areas that serve as pup nurseries. Entanglement deaths are severely undermining recovery efforts of these seals, a specie already on the brink of extinction. Not only this, but also this Entanglement in plastic debris has led to serious injuries and mortality with respect to the endangered stellar sea lion, with packing bands the most common entangling material. Moreover, in 2008 two sperm whales were found stranded along the California coast with significant amounts of fishing net scraps, rope and other plastic debris in their stomachs. (Weule, 2017) (Plastic Impacts on the Marine Environment, 2015)
Plastic and Human Health
Any plastic can leach, depending on the conditions (light, heat) as well as what additives it includes and this can be directly associated to cancer, birth defects, immune system problems and deficiencies, in addition to childhood development concerns.
Plastic is certainly hazardous for humans in several means; through direct toxicity present in lead, cadmium, and mercury mainly found in numerous fish in the ocean, which is very dangerous for humans. Or by Diethylhexyl phthalate (DEHP) contained in some plastics, considered as a toxic carcinogen.
Furthermore, BPA or health-bisphenol-A, used in many things including plastic bottles and food packaging materials, are of polymer chains that can break down over time, and may enter the human body in many ways including drinking contaminated water as well as eating fish exposed to the broken down toxins. Precisely, BPA has been identified as a chemical that disrupts hormones. (Andrews, 2016)
Shocking impacts of plastic pollution
Plastic pollution affects our economy, costing us limitless dollars spent on beach cleanups, tourism losses in addition to damages to fishing and aquaculture industries. Consequently, beaches and oceans have turned into landfills!
Get Plastic Out of Our Lives; Take Actions!
We, all, are responsible for our trash. For that reason, the solution to this marine litter can be through several actions, headed for less plastic production and consumption;
· Governmental regulations on plastics; apply fees or deposits
· By local and request a paper bag instead of plastic, or bring your own ones.
· Carry a reusable water bottle
· Bring your own cup
· Pack your lunch in reusable containers
· Say NO to disposable straws and cutlery and replace them by reusable steel, glass or bamboo straws and cutlery
· Slow down and dine in
· Store leftovers in glass jars
· Clean your home with natural ingredients (vinegar, lemon, sodium bicarbonate)
· Swap bathrooms bottles for soap bars
· Use natural oils to clean and moisturize
· Choose plastic-free natural deodorant
· Brush with bamboo
· Avoid synthetic clothes
· No more single serving plastic sachets
Figure 7 Recycle!
In brief, oceans occupy about 71% of earth’s surface. This necessitates their protection in order to be considered as a well adequate environment for living beings particularly humans who, in turn are affected by everything surrounding them including these “man-made” products. To achieve such goal, further awareness towards global environmental standards of water, air and soil should be given, in addition to the necessity of enlightening the serious effects created because of these reactions between Persistent, Bio-accumulative and Toxic compounds (PBTs) and micro-plastics in the marine environment, and finally identifying the anonymous quantities of plastics entering the oceans, and developing methods to measure and to limit these amounts.