Microplastic Contamination in Environment microbiologystudy

Any fragments or particles of plastic less than 5 mm in length are defined as microplastic. The microplastics are categorized into different types based on their origin, shape, and size, as discussed below.

Types of Microplastic

a. Origin of Microplastics

1. Primary Microplastics

Those plastics that are generated from the industries are called primary microplastics. For example; microbeads in cosmetics, toothpaste, and face wash, or microfibers from synthetic clothing and rope. This can be forbidden from the production as per their significant influence in ecosystems.  

2. Secondary Microplastics

Those plastics that are made by breaking down of large plastics into smaller fragments due to physical and chemical effects in nature are called secondary microplastics. It has a huge amount of potential to cause a problem as the discarded plastics continuously degrade into smaller pieces to form microplastics. The secondary microplastics can adsorb the other various contaminations and can cause long-term health impacts.

b. Based on size

The microplastics are further divided into the

1. Large Microplastics: The particles of microplastics, which have a size (1-5) mm in length. 
2. Small Microplastics: The particles of microplastics, which have a size (1μm-1mm) in length.

Similarly, it can also be divided as 

1. Femto-Size Plastics (0.02–0.2 µm)
2. Pico-Size Plastics (0.2 2 µm)
3. Nano-Size Plastics (2–20 µm)
4. Micro-Size Plastics (20–200 µm)
5. Meso-Size Plastics (200–2000 µm)
6. Macro-Size Plastics (0.2–20 cm) 
7. Mega-Size Plastic (20–200 cm)

c. Based on shape

1. Fragments: The smaller particles of plastics are caused by the breakdown of larger plastics, which are derived from utensils, plastic caps, and single-use plastic materials. 
2. Fibers: The non-biodegradable tiny pieces of plastic that are derived from clothing, diapers, cigarette butts, etc. They can clog the sewerage pipes and block the path of water.
3. Films: The thin form of plastic with a distinct shape like a sheet. 
4. Microbeads: The non-biodegradable plastic, which is less than one in diameter which, is derived from facial cleansers, soap, and toothpaste. They can block the intestine and cause the death of aquatic animals. 
5. Foams: The styrofoams found in food packages, cups, and packaging materials can leach to food and drinks and affect human health.



d. Based on the chemical composition

Polypropylene, polyethylene, polystyrene, polyamide, polyester, and acrylic etc. 

Pathway of Microplastics

1. Ingestion: The process gets exposed to the microplastic through direct ingestion. For example; Fruit and vegetables, seafood, bottled water, salt, alcohol, etc. According to WHO, the daily intake of 400 gm of fruits and vegetables like apples, pears, broccoli, lettuce, and carrots made ingestion of 53.09 * 106 p/day by humans. 
2. Inhalation: The process of getting exposed to the microplastic through inhalation. For example: Air. Humans can inhale microplastics through the air at 5.92 particles per day. 
3. Dermal Exposure: The process of getting exposed to microplastics through the dermal (skin) pathway of contact.



Impacts of Microplastics in Water

1. Impacts on Water bodies

The non-biodegradable plastic wastes were mostly discarded in water bodies like surface water, groundwater, and ultimately into the oceans, which creates the pollution of secondary microplastics and nano-plastics. It was assessed that oceans alone were contaminated with 4 million to 14 million tons of plastics in the early 21^st century.

2. Air pollution

Recently, microplastics have emerged as major sources of air pollution, which are found in the dust and air-borne fiber particles. The consequences of the inhalation of microplastics cause serious health effects to humans and animals. 

3. Impacts on Aquatic organisms

Microplastics have been discovered to the most in aquatic species in both marine and fresh-water environments. The microplastics get entangled in the digestive systems and tissues, which results in the death of the organism. Most of the birds and fish get confused with microplastic as a food. Besides, this microplastic also causes neurological and reproductive damage. Likewise, the entire marine food chain gets impacted from zooplankton to predatory organisms.

4. Impacts on human health

Recent studies showed that microplastic has been discovered in bottled drinking water, beer, fruit cans, food products, sea food, and table salt. In a similar way the microplastic has been encountered in human tissues and organs too.



Preventive Measures of Microplastic Contamination

1. Used eco-friendly and sustainable clothing like cotton, silk, wool, hemp, and other natural fibers instead of synthetic clothing such as polyester. 
2. Single-use plastics should be reduced by carrying own cloth bags, paper bags, or backpacks, replacing plastic straws, minimizing consumption of plastic bottled water, etc. 
3. Use eco-friendly and sustainable ways of making cosmetic products with natural ingredients and minimize the use of microbeads containing cosmetics. 
4. Minimize the consumption of sea foods, which allow microplastic ingestion in the human body and cause health problems. 
5. Maintain and implement proper managerial action in accordance with acts, rules, and regulations. 
6. Make behavioral changes to limit plastic consumption rates throughout the world. 

Conclusion

The current situation has made microplastic contamination became a serious concern. Microplastics contamination endangering aquatic organisms, pose risk to human health and the whole ecosystem. So limiting the use of plastics and shifting to eco-friendly and sustainable practices is a measure to reduce the microplastic pollution in the environment. 

References

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