In the past 70 years, 8.3 billion tons of plastic have been produced worldwide, only 9%have been recovered, and most of the remaining 91%have been released to the environment and a small part has been burned. Over time, the plastic waste released into the environment will be degraded through environmental weathering, physical collision, etc., and then plastic with a size of less than
Micro plastic in the air
In the past, micro -plastic was only deposited in the ocean and soil, but the current research found that a large number of micro -plastic exists in the air. A research team in
Under normal circumstances, micro -plastic is difficult to see with the naked eye. Researchers collect micro -plastic deposition samples in the atmosphere of
Through fluorescent microscope identification, the researchers evaluated the deposition rate of micro -plastic in the atmosphere of two sampling points in the
Prior to this, other cities, such as
From the perspective of micro -plastic ingredients, researchers have observed 8 polymer types, polyethylene (PE, commonly used in making plastic bags, thin film, plastic barrels, etc.) is the richest polymer type observed, occupying all polymer types 39%, followed by polycarbonate (PC) and polyethylene pheenate (PET, commonly used for drinking water and drinks), which account for 26%and 22%of all polymers, respectively. PE and PET are the most common packaging materials. PCs are mainly used for electrical and electronic applications, and these three materials are often used in the construction industry, so they occupy most of the micro -plastic.
However, researchers believe that the geographical environment in the
Micro -plastic in the bottom of the sea and the ocean
A recent study of a research team at the
For the first time, the researchers carried out high -resolution reconstruction of micro -plastic pollution in the sedimentary of the
Studies have found that micro -plastic remains unchanged in marine sediments, and the quality of micro -plastic deposited in the bottom of the sea can correspond to global plastic output from 1965 to 2016. The specific result is that since 2000, the number of plastic particles deposited on the bottom of the sea has doubled, and they have not only decreased with the production and global use of these materials, but also have been increasing.
Since the 1980s, especially in the past 20 years, the accumulation of polyethylene and polypropylene particles in packaging, bottles and foods, and the accumulation of polyester particles in synthetic fibers in clothing fabrics have gradually increased. These three grains The number of seabeds per kilogram of seabed reaches 1.5 mg, of which the polypropylene content is the most, followed by polyethylene and polyester.
This result is similar to that of
Through the application of the most advanced imaging technology to quantify the micro plastic particles with a size of 11 microns, researchers have found that once micro -plastic is trapped on the bottom of the sea, it will no longer degrade. This can be sports. Therefore, the production process of micro -plastic may be mainly plastic garbage on the beach, sea or seawater. The micro -plastic of the 1960s still stayed on the bottom of the sea, leaving the characteristics of human pollution.
For micro -plastic in the ocean and the sea, a UN survey believes that the filtering mouth on cigarettes is an important source of micro -plastic. Every year, the global tobacco industry produces 6 trillion cigarettes for 10 billion smokers worldwide. These cigarette filters are mainly composed of micro -plastic called acetate fiber. When these cigarette butts are released to the environment, they will be decomposed and released by factors such as sunlight and moisture.
The cigarette butt is the most discarded garbage in the world, and it is difficult to recover. About 766.6 billion kilograms of toxic waste produces the world ’s cigarette heads every year. They are also the most common plastic garbage on the beach, which increases the pollution of micro -plastic to marine ecosystems.
The combination of micro -plastic and toxins
The biggest problem of micro -plastic is that you can enter the food chain through drinking water, diet, etc., and eventually enter the human body to bring a series of damage to the human body. Micro -plastic will enter the cells, pass through the blood brain barrier, and may accumulate in the lungs, testicles, liver and brain organs. Now the micro plastic is detected in the placenta. However, how much micro -plastic needs to be reached in the body to cause damage, and there is no exact research data yet.
However, another situation may exacerbate people's concerns about micro -plastic, that is, micro -plastic and some substances depend on each other to produce greater toxicity.
American researchers have just published in the "Environmental Science and Technical Express" in the American Chemistry Society (ACS) that micro -plastic and some substances can be attached to each other. As a result condition. For example, when chromium is attached to a micro -plastic, ultraviolet filtrates used in sunscreen and other products will make metal chromium more toxic, and the problems caused by wild animals, plants or humans may be more serious than the initial imagination.
Earlier studies have shown that heavy metals are easily attached to micro -plastic, which may cause potential damage to aquatic creatures. But in addition to sticking to other pollutants, micro -plastic and material mixtures on them will also interact and change their chemical properties.
Some metals, such as chromium (CR), may show different oxidation status on the surface of the micro plastic. Although CR (III) is relatively safe, CR (VI) is toxic. Therefore, researchers tried to clarify how the oxidation state changed when CR and micro -plastic are combined, and a common organic pollutant, how the ultraviolet filtration molecule affects the oxidation state.
Researchers created mixtures of chromium and polystyrene micro plastic particles. In the absence of UV filters, micro -plastic can gather more chromium. In addition, CR has a high oxidation state in a mixture containing filters. The research team tested whether this increased oxidation state was converted into environmental toxicity to micro algae population. When exposed to a mixture containing filter molecules, the growth of micro algae is suppressed, which indicates that chromium attached to micro plastics and through ultraviolet filter agents will produce greater toxicity.
Researchers believe that micro -plastic can help transform pollutants into a more harmful form, which is the harmful effect of micro -plastic that has not been found before. For micro -plastic, more research will be required to confirm it on people, creatures, and ecology.
Therefore, it is an emergency and important topic to solve the problem of plastic pollution through plastic recycling. Interests are related to the present and future. It is to achieve plastic that can bring our lives and bring major cheapness while achieving harmonious development and the environment of the environment.