Microplastic Contamination in the Environment: Pathways, Impacts, and Preventive Measures

Table of Contents

• Introduction to Microplastic Contamination in Environment
• Types of Microplastic
• Pathway of Microplastics
• Impacts of Microplastics in Water
• Preventive Measures of Microplastic Contamination
• Conclusion
• References

Introduction to Microplastic Contamination in Environment

• Microplastic contamination in the environment refers to the presence of very small plastic fragments or particles.
• Any plastic fragment or particle that is less than 5 millimeters in length is defined as a microplastic.
• These microplastics are not uniform and can be categorized into different types.
• The classification of microplastics is based on multiple factors, including their origin, shape, and size.
• Each of these factors—origin, shape, and size—plays an important role in understanding the characteristics and environmental behavior of microplastics.

Types of Microplastic

a. Based on Origin

• Primary Microplastics: Generated directly from industries. Examples include microbeads in cosmetics, toothpaste, and face wash, as well as microfibers from synthetic clothing and ropes. These significantly influence ecosystems and their production can be restricted to reduce contamination.
• Secondary Microplastics: Formed when larger plastics break down into smaller fragments due to physical and chemical effects in nature. Discarded plastics continuously degrade into microplastics. They can adsorb other contaminants and cause long-term health impacts.

b. Based on Size

• Large Microplastics: 1–5 mm in length.
• Small Microplastics: 1 μm–1 mm in length.

Detailed Size Categories:

• Femto-Size Plastics: 0.02–0.2 µm
• Pico-Size Plastics: 0.2–2 µm
• Nano-Size Plastics: 2–20 µm
• Micro-Size Plastics: 20–200 µm
• Meso-Size Plastics: 200–2000 µm
• Macro-Size Plastics: 0.2–20 cm
• Mega-Size Plastics: 20–200 cm

c. Based on Shape

• Fragments: Small particles caused by breakdown of larger plastics, derived from utensils, plastic caps, and single-use plastic items.
• Fibers: Tiny, non-biodegradable plastic pieces from clothing, diapers, and cigarette butts. They clog sewerage systems and block water flow.
• Films: Thin plastics in sheet-like forms.
• Microbeads: Non-biodegradable plastics less than 1 mm in diameter, derived from cleansers, soaps, and toothpaste. They can block intestines and cause aquatic animal deaths.
• Foams: Styrofoams found in food packages, cups, and packaging materials, which can leach into food and drinks, posing health risks.

d. Based on Chemical Composition

• Common types include polypropylene, polyethylene, polystyrene, polyamide, polyester, acrylic, and other synthetic polymers.

Pathways of Microplastic Exposure

1. Ingestion

• Microplastics can enter the human body through direct ingestion.
• Common sources include fruits, vegetables, seafood, bottled water, salt, and alcohol.
• According to the World Health Organization (WHO), a daily intake of 400 g of fruits and vegetables (such as apples, pears, broccoli, lettuce, and carrots) results in an estimated ingestion of 53.09 × 10⁶ particles per day by humans.

2. Inhalation

• Exposure to microplastics also occurs through inhalation of air.
• Humans can inhale microplastics at an average rate of 5.92 particles per day.

3. Dermal Exposure

• Microplastics may also enter the body through the dermal (skin) pathway of contact.
• This pathway involves direct exposure of the skin to microplastic particles, though its contribution is relatively lower compared to ingestion and inhalation.

Impacts of Microplastics in Water

1. Impacts on Water Bodies

• Non-biodegradable plastic wastes are frequently discarded into surface water, groundwater, and oceans, leading to pollution by secondary microplastics and nano-plastics.
• It has been assessed that the oceans alone were contaminated with 4–14 million tons of plastics in the early 21st century.

2. Air Pollution

• Microplastics have recently been recognized as a major contributor to air pollution.
• They are present in dust and airborne fiber particles, which can be inhaled by humans and animals.
• Inhalation of microplastics can lead to serious health effects, affecting the respiratory system and overall health.

3. Impacts on Aquatic Organisms

• Microplastics are found extensively in aquatic species across both marine and freshwater environments.
• They often become entangled in the digestive systems and tissues of organisms, leading to death.
• Birds and fish frequently mistake microplastics for food, resulting in ingestion.
• Exposure also causes neurological and reproductive damage in aquatic species.
• The entire marine food chain, from zooplankton to top predators, is negatively impacted by microplastic contamination.

4. Impacts on Human Health

• Studies have confirmed the presence of microplastics in bottled drinking water, beer, canned fruits, food products, seafood, and table salt.
• Microplastics have also been detected in human tissues and organs, raising concerns about long-term health consequences.

Preventive Measures of Microplastic Contamination

• Use eco-friendly and sustainable clothing such as cotton, silk, wool, hemp, and other natural fibers instead of synthetic clothing like polyester, which shed harmful microfibers into the environment.
• Reduce single-use plastics by carrying your own cloth bags, paper bags, or backpacks, replacing plastic straws with reusable alternatives, and minimizing the consumption of plastic bottled water.
• Prefer eco-friendly and sustainable cosmetic products made with natural ingredients, and minimize or avoid the use of cosmetics that contain microbeads, as these directly contribute to microplastic pollution.
• Minimize the consumption of seafood, since it is a major source of microplastic entry into the human body and can lead to serious health problems.
• Ensure the maintenance and implementation of proper managerial actions in line with acts, rules, and regulations to control plastic use and disposal effectively.
• Encourage behavioral changes worldwide to reduce plastic consumption rates by promoting sustainable habits and lifestyle adjustments.

Conclusion

• The current situation shows that microplastic contamination has become a serious global concern.
• Microplastics are endangering aquatic organisms, posing risks to human health, and threatening the entire ecosystem.
• To address this issue, it is essential to limit the use of plastics and adopt eco-friendly and sustainable practices as effective measures to reduce microplastic pollution in the environment.

References

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Encyclopaedia Britannica, T. Editors. (2024, August 27). Recycling. Encyclopedia Britannica. Retrieved September 24, 2024, from https://www.britannica.com/science/recycling

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Kye, H., Kim, J., Ju, S., Lee, J., Lim, C., & Yoon, Y. (2023). Microplastics in aquatic systems: Environmental impacts and potential hazards. Heliyon, 9(3), e14359. https://doi.org/10.1016/j.heliyon.2023.e14359

Swim Drink Fish. (2023). The five main types of microplastics. Swim Drink Fish. Retrieved September 24, 2024, from https://www.swimdrinkfish.ca/lake-ontario-waterkeeper/blog/2016/11/15/zooming-in-on-the-five-types-of-microplastics

Yang, S., Zhou, M., Chen, X., Hu, L., Xu, Y., Fu, W., & Li, C. (2022). Comparative review of microplastics in lake systems across different regions and countries. Chemosphere, 286, 131806. https://doi.org/10.1016/j.chemosphere.2021.131806