2. Impact of Microplastics pollution in Marine environment
Dissertation for the partial fulfilment of the M.Sc. degree in Marine Science, University of
Calcutta
Submitted by
Sneha Dhali
Roll Number – C91/MRS/201014
Registration Number – 144-1222-1252-16
Department of Marine Science,
University of Calcutta
• Supervised by
Prof. TARUN KUMAR DE
Department, Marine Science
University of Calcutta
3. Introduction
Plastic are widely used around the world due to case of manufacturing, low cost, stable chemical properties, and good water
resistance, the production has been steadily increasing year by year. The commonly used plastics include Polystyrene, Nylon,
Polyurethane, Polypropylene, etc. These plastics are gradually decomposed by the physical, chemical and biological effect in
the environment, plastic are easily fragmented under the effect of environmental forces, however, It takes about a long time
for these plastics to be completely decomposed over 300 million tons of plastics are produced every year for use in a wide
variety of application. At least 8 million tons of plastics end up in our oceans every year, and make up 80% of all marine debris
from surface waters to deep-sea sediments. Plastic pollution threatens food safety and quality, ocean health, human health,
coastal tourism will form plastic debris with a small particle size; plastics debris whose diameter is less than 5mm is called
micro-plastics .The micro-plastics pollution has caused many to marine life and has already aroused widespread concern.
Keywords: micro-plastics, fish, human and other aquatic marine
ecosystem
4.
5. Source and types of marine micro-plastics : -
Plastics are chemically stable and can exist in the environment for hundreds years or longer. Due to the cheapness
and wide applicability of plastics the global plastics industry has developed rapidly
since the 1950’s, the production of global plastic growing by 4% every year. About 10% of the waste plastics finally
discharge into the ocean through various channels, which account for about 60% to 80% of marine waste and they
are even as high as 90% to 95% in some area. What is more with the global population growth and the increasing
demand for plastics products, the amount of plastics discharged into the ocean has also increased dramatically.
About 8 million tons of plastics flow into the ocean every year. Micro-plastic in the ocean are usually derived from
inland river flow, fisheries and oil, etc.,. All kinds of plastics particle added in daily necessities plastic raw materials
used in industry etc. Finally flow from the river to the ocean. The main chemical components are Polyurethane
and Polystyrene. In addition the plastic waste in the coastal zone into the ocean will also cause Pollution. At
present the main sources of micro-plastics in the ocean are: land flow : plastics waste such as plastic bag, foam
and fibers on land are washed by wind and rain, and flow into marine environment through river, which cause
marine plastic pollution. Land flow is a major source of micro-plastics in marine environment.
Costal Tourism : At the seaside tourist attractions such as density populated beaches , due to
low specific heat, rapid heating, mineral water bottles and other plastic waste that are randomly
discarded by tourists, they are easily broken into micro-plastics in the marine environment.
Ship transportation :
Ship throw a lot of plastic wastes to the ocean is also an importance source of micro-plastics. In
addition marine shipping accidents can also cause a large number of plastic products to flow into
the ocean.
6.
7.
8. Distribution and characteristic of marine micro-plastics:-
Micro-plastics are distributed on the surface of water bodies, near- shore beaches and water bottom
sediments and there are large spatial differences, Generally speaking the pollution of micro-plastics in
coaster waters is serious, which is mostly related to the intensity of human production activities. The
contents of coastal sediments are higher than that deep sea sediments. At present, the shapes, sizes,
colors and densities of micro-plastics collected by people are different, depending on the type of
plastics. Because micro-plastics are subjected to various environmental forces during the production
process, the shape is irregular, the surface is uneven, and there are many cracks, they are often
attached to crude oil, iron oxides , organic pollutants ,bacteria and even viruses etc, are subject to
monsoon and ocean currents other external forces and gather in different sea areas.
9. Impacts of micro-plastics in marine aquatic ecosystem :-
Micro-plastic pollution has become a serious threat to the aquatic ecosystem. Micro-plastic can create
obstacles in photosynthesis in algae like Chlorella sp.
and Scenedesmus sp. threatening the basis of primary production. It affects electron donor site and
electron transport chain, resulting in the formation of oxygen reactive species which causes oxidative
stress. Micro-plastic pollution has a tendency to form aggregates with phytoplankton, which may
induce bioaccumulation. Bioaccumulation can result in the entry of MP to the food web and
subsequently to the food chain. MP association with microscopic algae can also result in growth
inhibition. Others effects include deformed thylakoid , unclear pyrenoid detachment of plasma from
the cell wall, cell wall thickening. Zooplanktons can ingest MP by mistaking them for food . which can
affect – their growth and reproduction .By ingesting MPs fishes may suffer from intestinal blockage ,
physical damages, histopathological damages in intestines, changes in behavior and change in lipid
metabolism, Ingestion of 14 MP particles can increase the motility percentage by 50% in turtles. PE can
reduce the visibility of roots in duckweed.
PE (Polyethylene)
11. Impact of micro-plastics on marine fishes :-
Marine micro-plastics will affect many aspects of the marine fish. The micro-plastics can have a toxic effect on
fish and other aquatic life, including food intake, delaying growth, causing oxidative damage and abnormal
behavior. In addition, nano – scale micro-plastics will penetrate the biological barrier and accumulate in
tissues , resulting in the generation of ROS. Affecting lipid metabolism and may further affect life at the
molecular level. For Example, fishes that can nano-sized polystyrene particles through the aquatic food chain
had significant differences in body weight , serum triglyceride to cholesterol ratio, cholesterol content in
muscle and liver and other metabolic parameters. Fish is an important group in the marine eco system, it plays
a key role in the process of material circulation, energy flow and information transmission , and its health level
can be directly related to the stability of the structure and function of the marine ecosystem. Moreover,
because fish is an important source for humans to obtain animal protein, marine pollutants can enter the
human body by enriching in fish and threaten human health. Therefore, it is of great significance to carry out
research on the ecological effects of microplastics on fish . Micro-plastics are widely distributed in the marine
environment because of their small particle sizes, they are easily eaten by marine life, and produce a series of
toxic effects, including inhibition of growth and development, impact on feeding and behavioral ability ,
reproductive toxicity, immunity toxicity, genetic damage etc.
12. Impact of micro-plastics on marine fishes :-
Marine micro-plastics will affect many aspects of the marine fish. The micro-plastics can have a toxic effect on
fish and other aquatic life, including food intake, delaying growth, causing oxidative damage and abnormal
behavior. In addition, nano – scale micro-plastics will penetrate the biological barrier and accumulate in
tissues , resulting in the generation of ROS. Affecting lipid metabolism and may further affect life at the
molecular level. For Example, fishes that can nano-sized polystyrene particles through the aquatic food chain
had significant differences in body weight , serum triglyceride to cholesterol ratio, cholesterol content in
muscle and liver and other metabolic parameters. Fish is an important group in the marine eco system, it plays
a key role in the process of material circulation, energy flow and information transmission , and its health level
can be directly related to the stability of the structure and function of the marine ecosystem. Moreover,
because fish is an important source for humans to obtain animal protein, marine pollutants can enter the
human body by enriching in fish and threaten human health. Therefore, it is of great significance to carry out
research on the ecological effects of microplastics on fish . Micro-plastics are widely distributed in the marine
environment because of their small particle sizes, they are easily eaten by marine life, and produce a series of
toxic effects, including inhibition of growth and development, impact on feeding and behavioral ability ,
reproductive toxicity, immunity toxicity, genetic damage etc.
13. Fish Species
Micro-plastic
Type
Particle Size Concentration
Toxicological
Effects
Pomatoshistos
Microps
PE 1~5 um 184 ug/L ACHE activity decrease
Acanthochormis
polyaconathus
PET 1~2 um 0~0.86 ug/L
Growth decrease
Dictrarchus
Labrax
PE 10~45 um 10~100 pes/ug Mortlity incrase
Dictrarchus
Labrax
PVC <0.3mm 0.1%( quality ratio) Inflammation
Dictrarchus
Labrax
Polymer 1~5 um 0.69mg/L Swimming spreed decrease
Oryzais
Lapites
PE <1 mm 8ug/L
Male-abnormal proliferation
of sperm cells
Carrassius
Carrassius
PS (24.7+
- 0.2)nm 130mg Vitality decrease
Danioererio PS (24.7+
- 0.2)nm 1.5X1013 pcs/ L Body length decrease
Danioererio PE,PP,PA,PVC 70 um 1.0mg /L
Intestinal injury
Fig: - Toxicological effect of micro-plastic on fish.
14. Cause genetic damage :-
Micro-plastics can cause genetic damage to marine life. Studies have shown that micro-plastics absorb
polycyclic aromatic hydrocarbons , which causes immunotoxicity , neurotoxicity and genotoxicity to M gallo
provincialis), and can cause genetic damage to mussels. However at present there are few studies on the
genotoxicity of micro-plastic of marine life.
15. Impact of micro-plastics on Human : -
Micro-plastic can enter human system is various ways humans may consume MP by consuming contaminated with
MP. Analysis of salt samples made of sea water, around the globe has confirmed the presence of MP, human can
intake MP by consuming these salts. MP has the potential to cause cytotoxic effects on human cerebral and
epithelial cells. Fine MP can also ceoss the cell membranes, bloodbrair barrier and the placenta and may result in
oxidative stress, cell damage, information and hindrance in energy allocation. Humans may consume several
harmful chemicals like phthalates, heavy metals, bisphenol A, pesticides, flame retardants and PCBS fertilizers
along with MPS which are potential endocrine disruptors and mutagens. Consumption of fishes contaminated with
MP can also result in skin irritations, respiratory problem cardiovascular disease, digestive problems reproductive
effects.
Other impacts:-
If plastic waste is incinerated, it releases carbon dioxide into the atmosphere ,thereby increasing carbon emissions .
Plastic waste damages the aesthetic value of tourist destinations, leading to decreased tourism related incomes. It leads
to major economic costs related to the cleaning and maintenance of the sites.
16.
17.
18. Conclusion :-
At present, the pollution of marine micro plastics has become more and more
serious and has become a global pollution incident, But there is a lack of effective
treatment methods. We must star eliminate more pollution with various methods.
In future work, the size, the shape , and related contaminants should be considered
to better evaluate the micro plastic.
