A survey by foreign agencies found that there was far less waste plastic floating in the ocean than estimated, at only one-third of the original estimate of 4 million to 12 million tonnes. And plastic degradation cycle is generally 200 to 400 years, so where exactly is the waste plastic? The team of Professor of Ecological Toxicology of Ocean Life College, Ocean Life College of Ocean University of China, published its marine microplastic research results in the leading journal Environmental Pollution, and the results show that marine plastics are difficult to degrade in a short period of time.
Yu Shaoguo told reporters that each year from the land into the ocean about 6-12 million tons of plastic waste, these plastic fragments in the environment will gradually crack into microplastics with a particle size of less than 5 mm. These microplastics are chemically stable and can exist in the environment for hundreds to thousands of years and are transported over long distances through ocean currents and wind, spread throughout the ocean. These microplastics are easily ingested by marine organisms and are transmitted through the food web to affect entire marine ecosystems. Of course, the effect sly lying is devastating.
Their results also show that microplastics have a large surface area, easy to enrich toxic and harmful substances, marine life has a combined toxic effect.
However, not all researchers agree with the view that marine plastics are difficult to degrade. Royle, a researcher at the University of Hawaii, has found plastic fragments in seawater that can be broken down into gases such as carbon dioxide, methane and ethylene when exposed to sunlight. He believes that once the plastic decomposition program is activated, they will continue to degrade even when they are not seen in the light of day.
The National Engineering Research Center of Engineering Plastics of the Chinese Academy of Science and Technology is one of the highest level polymer materials research and industrialization bases in China, and the first research on marine degradation materials has been carried out in China. Through many experiments and comparisons, Wang Gexian, a senior engineer at the institute, found that materials with good biodegradability in soil and compost were not degraded at an unsatisfactory rate in seawater.
Looking at the bottom, Wang Geman found the answer: “The polyester material compost process is an enzyme-promoted hydrolysis reaction under the action of microorganisms, and the low temperature of seawater, the small number of specific microbial species, it is difficult to have the conditions for biodegradation, so most polyester materials in the seawater degradation cycle is very slow, even difficult to degrade.” “
“Marine plastic waste will triple between 2015 and 2025. That’s what Boyd, the UK’s chief scientist for the environment, predicted in the Prospective Future of the Oceans report. So where does this multiplied amount of marine plastic go? One answer may be the stomach son of a variety of fish.
When plastic is “eaten” into the belly of a fish, it is difficult to be digested like ordinary food, but becometoxic, far-reaching impact on the physical development of fish.
Since 2017, the team has conducted research on microplastic pollution investigation and biotoxicity. In terms of biotoxicity, for example, they found that microplastics not only damage the structural characteristics of tissues such as the intestinal tract, pab, gonads and oxidative stress prevention systems, but also interfere with the reproductive and sub-generation development of fish, and for the first time confirmed that microplastics have reproductive endocrine disturbance effects.
In addition, they found that high concentrations of microplastics accumulate on the shells of seawater cyanosis, interfering with the development of embryos and early-life fish, and their joint exposure experiments found that low-concentration microplastics could reduce the early developmental toxicity of fitosa to sea water cyanosis by reducing the amount of persistent organic pollutants, the fia in the fish.
These important findings by the Shaoguo team provide an important reference for evaluating the ecological risks of marine microplastics. And Wang and his team members managed to get out of the difficult situation. Starting from molecular design and two-phase synthesis, they introduced non-enzyme hydrolysis groups into biodegradable polyester systems by means of polymer synthesis modification and mixed modification, and realized the overall controlled degradation of materials in seawater.