Team:NWU-CHINA-A/Plastic Pollution
Overview
Another important aim of our project is to address the environmental pollution caused by antibiotics and plastics. Synthetic biology provides a very useful solution to various environmental pollution problems encountered in ecology. Such as the use of synthetic biology strains to solve the problem of oil spills and the production of clean new energy. Our project also adopts this idea, we use synthetic biology method to transform bacterial strains to produce antimicrobial peptides, so as to solve the ecological environmental pollution problems caused by the plastic part of band-aids and antibiotics. Next, we will describe in detail the current situation of environmental pollution, which is an important driving force for our project.
1. Plastic pollution
Evidence abounds for plastics' potential to pollute and disrupt important natural processes and quality of life. Plastic fragments, varying in size from macrodebris (bigger 20 mm), to mesodebris (2–20 mm), to microdebris (smaller than 2 mm) are polluting the world's oceans. Using surface net tows, 334,000 plastic items were collected in 1999 per square kilometer in the North Pacific Subtropical Gyre, a mass equivalent to 5.1 kg.The amount of anthropogenic litter in aquatic and terrestrial environments has increased dramatically over the last few decades; approximately 60e80% of which is plastic. Mass production of plastics began in the 1950s, and currently exceeds 280 million tones globally. It is estimated that 4.8 to 12.7 million metric tons of mismanaged plastic waste enters the oceans from coastal countries each year. When introduced into natural environments, plastics can be transported from land to river, and eventually reach the ocean. During the migration, plas-tics can lead to detrimental impacts on natural surround-ings, wildlife, and even human health. Meanwhile, plastics could act as vectors for persistent organic pollutants (POPs), heavy metals, microorganisms in the environment.
F1:How microplastics （very small plastic particulates and fibres）contaminate
the Earth’s ecosystems
2. Plastic Pollution is Diverse
F2:Diversity of plastic pollution and cycles of plastic in the environment.
3. Plastic Pollution is Persistent
However, it likely takes much longer time for plastics to degrade in the environment owing to the high-polymer nature when compared to other organic materials.
4. Plastic Pollution is a Global Issue
Plastics can not only directly enter the aquatic, atmospheric, and terrestrial systems through diverse pathways, but also migrate freely among these various systems. Here, we propose the “plastic cycle”, which likely takes place in the environment, similar to well-known carbon or nitrogen cycle in the environment. Specially, plastic cycle is the process of plastics to migrate among water, atmosphere and soil through different pathways. For example, light plastics are more easily transported in different systems with the action of various forces, leading to the spread of plastics to some remote areas in the environment. Studies have demonstrated the presence of plastics in uninhabited areas, such as pristine mountain catchment, polar regions, and deep sea . Consequently, plas-tic pollution is a global issue with no boundaries in the world owing to the long-distance transport in different systems.
F3:Summary of potential human health impacts of microplastics exposure
5. Status and Possible Measures
Synthesis of current knowledge, uncertainty and recommended actions relevant to environmental and human health concerns arising from current production, use and disposal of plastics.
6. Future issues
Whereas plastics are an essential part of modern society, emerging human health effects and documented ecological impacts demand the development of smarter and safer materials for future use.Nearly 30% of plastic waste is still landfilled in Europe, and the current EU plan is to reduce landfilling of plastic to no more than 10% by 2030. In the USA, 53% of total municipal solid waste (MSW) is landfilled, with plastic waste representing 13% of MSW. The recycling rate of nondegradable plastic remains stubbornly low globally. While recycling technologies are available, the high price and relatively low quality of the recycled plastic limits market applications. Biodegradable plastic are especially interesting for nondurable applications such as packaging and agricultural films where biodegradability offers new end-of-life management options not open to nondegradable plastic, e.g., composting and anaerobic degradation. Biodegradability is an advantage when inadvertent environmental release occurs to aquatic and terrestrial environments.
These are our thoughts on environmental pollution in ecology, and our project is also a solution to environmental pollution in ecology through the thinking of synthetic biology.We also hope that our project will convey this way of thinking to future iGEMers.
References
[1]Akdogan Z, Guven B. Microplastics in the environment: A critical review of current understanding and identification of future research needs. Environ Pollut. 2019 Nov;254(Pt A):113011.
[2]Li P, Wang X, Su M, Zou X, Duan L, Zhang H. Characteristics of Plastic Pollution in the Environment: A Review. Bull Environ Contam Toxicol. 2020 Mar 12.
[3]Halden RU. Plastics and health risks. Annu Rev Public Health. 2010;31:179-94.
[4]Narancic Tanja, Verstichel Steven, Reddy Chaganti Srinivasa, et al. Biodegradable Plastic Blends Create New Possibilities for End-of-Life Management of Plastics but They Are Not a Panacea for Plastic Pollution.. 2018, 52(18):10441-10452.
[5]Karbalaei S , Hanachi P , Walker T R , et al. Occurrence, sources, human health impacts and mitigation of microplastic pollution[J]. Environmental Science & Pollution Research, 2018.
[6]Thompson Richard C., Moore Charles J., vom Saal Frederick S., et al. Plastics, the environment and human health: current consensus and future trends. 2009, 364(1526):2153-2166