Plastic Recycling Is an Important Way to Solve the Problem of Plastic Pollution

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 5 mm becomes micro -plastic (MP), including particles, fiber or thin film shapes, forming a major ones Material pollution.

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 New Zealand found and analyzed and analyzed the micro -plastic particles with a diameter of 0.01 mm in the city with a complex chemical method, and for the first time calculated the total quality of micro -plastic in urban air. The city of Auckland alone has 74 tons of micro -plastic every year from the air to the urban area, equivalent to more than 3 million plastic bottles.

Under normal circumstances, micro -plastic is difficult to see with the naked eye. Researchers collect micro -plastic deposition samples in the atmosphere of New Zealand, and use the luminous colored dyes to identify micro -plastic. Essence

Through fluorescent microscope identification, the researchers evaluated the deposition rate of micro -plastic in the atmosphere of two sampling points in the Auckland region, and found that 4885 micro -plastic particles could be found in an average daily air per square meter of air. The micro -plastic settlement rate observed by urban sites has reached 5955 micro -plastic/square meters/day. The micro -plastic settlement rate in the residential area is more serious, which is 33,495 micro -plastic/㎡/day.

Prior to this, other cities, such as London, Burger, Germany, and Paris, France, they also found that there are micro -plastic in the air. London is 771/square meter/day (a research report published in 2020). /Square meter/day (2019), Paris has 110/square meters/day (2016). Obviously, the sedimentation rate of micro -plastic in the air in Auckland is much higher than that of London, Burger and Paris.

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 Auckland region has a great impact on micro -plastic in the air. The high level of micro plastics in the Auckland region may be very related to the nearby ocean and wind direction. The correlation between micro -plastic settlement rate and sea wind shows that micro -plastic in coastal air may originate from the marine environment, and the waves of the Auckland Hamulaki Bay may spread the micro -plastic in the sea to the air and then pollute the air environment. The high sedimentation rate of micro -plastic may also be related to the wind direction. The micro -plastic level in the air is related to the wind direction from Auckland West District, and the West District is the direction of the center of Auckland.

Micro -plastic in the bottom of the sea and the ocean

A recent study of a research team at the Institute of Environmental Science and Technology of the University of Barcelona, Spain found that in the past 20 years, the total micro -plastic deposited on the bottom of the sea has doubled. Type and quantity correspond to.

For the first time, the researchers carried out high -resolution reconstruction of micro -plastic pollution in the sedimentary of the Mediterranean to analyze the situation of the underwater micro plastic. The bottom of the sea is considered to be the ultimate convergence of micro -plastic floating on the sea, but people have always been unknown to the historical evolution, sedimentation and sedimentation of micro -plastic in the sea.

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 New Zealand researchers that the most component of micro -plastic in the air is similar to polyethylene. Spanish researchers collected seal sediments on the marine inspection ship Sarmiento de Gamboa in November 2019. The inspection ship departed from Barcelona and headed to the Erbro Delta coast of Tarradana, Spain. This area is located in western Mediterranean, and the Erbro Delta River is considered to be a gathering area of several pollutants including micro -plastic. In addition, the sediment in the Erbro River is higher than the sedimentation rate of the Gonghai.

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.