Views: 3327 Author: TH-CS2 Publish Time: 2017-12-13 Origin: Site
Plastic bags do bring convenience to our lives, but the convenience of this time brings long-lasting harm.
Plastic bags have a low recycling value. In addition to the 'visual pollution' pollution that occurs in urban streets, tourist areas, water bodies, and both sides of highways and railways during the use process, there are still potential hazards. The plastic structure is stable and is not easily degraded by natural microorganisms. It does not separate in the natural environment for a long time. This means that if waste plastic waste is not recycled, it will become a permanent and continuous accumulation of pollutants in the environment, which will cause great harm to the environment.
First, it affects the development of agriculture. The accumulation of waste plastic products in the soil will affect the absorption of nutrients and moisture by crops, which will lead to a reduction in crop yields.
Second, it poses a threat to the survival of animals. Waste plastic products discarded on land or in water are eaten by animals as food, causing the animals to die. Last year, there were 20 families of herdsmen near Qinghai Lake. As a result, nearly 1,000 goats died. The economic loss was about RMB 300,000. Sheep like to eat oily residues wrapped in plastic bags, but often eat together with plastic bags, because of the plastics eaten for a long time in the stomach is difficult to digest, these sheep's stomach is full, and can no longer eat Things can only be starved to death in the end. Such things are common in zoos, pastoral areas, rural areas, and the ocean.
Thirdly, landfilling of waste plastics with landfills will not only occupy a large amount of land, but the occupied land will not be restored for a long time, which will affect the sustainable use of land. Waste plastic products entering domestic waste will not degrade if they are landfilled for 200 years. It is extremely harmful to the land, changing its pH, affecting the absorption of nutrients and water by crops, resulting in a reduction in agricultural output. Discarding plastic products in water or on land will not only affect the environment, but will also lead to death if swallowed passively. This destroys the ecological balance.
Fourth, high temperatures decompose toxic substances. Plastic products are no toxic substances, but because of its incomplete equipment for recycling, the process is simple, and many manufacturers have no legal business license, resulting in the reproduction of plastic products at a temperature of 65 °C At that time, toxic substances will be precipitated and infiltrated into foods, which will cause harm to the important parts of the human body such as the liver, kidneys, reproductive system, and central nervous system.
'White pollution' mainly refers to two negative effects on the 'visual pollution' and 'potential hazards' caused by the environment.
'Visual pollution' refers to the destruction of city views and landscapes that are scattered in the city and discarded by people's plastic waste. For example, a large number of polystyrene foam plastic tableware scattered on both sides of the railways, rivers and lakes, and ultra-thin plastic bags flying around or hanging on the branches have brought people a bad visual stimuli. The people strongly reflect this.
The "potential crisis" refers to the environmental problems caused by plastic waste entering the natural environment and difficult to degrade. The hazards include the following:
First, it is not easy to recycle, because the cost of recycling is high, but the utilization rate is low. Businesses can be said to be unprofitable, and because its recycling price is very low, it is difficult to attract the general public to carry out 'white recycling' work. Therefore, the phenomenon that it is difficult to recycle occurs.
The second is difficult to degrade. The white waste recovered is not easy to handle. At this stage, the main treatment methods are incineration and landfill. If it is burned, it will produce a large amount of toxic fumes, pollute the atmosphere, and promote the formation of acid rain. As for landfilling, it will be buried for 100 years. It is absorbed by nature and has great harm to the land, changing its pH, affecting the absorption of nutrients and water by crops, resulting in agricultural production cuts. As for plastic products abandoned in water or on land, it will not only affect the environment, but if it is swallowed passively, It will lead to death. This destroys the ecological balance.
Third, high temperatures decompose toxic substances. Plastic products do not contain toxic substances. However, because its recycling and reuse equipment is not perfect, the process is simple, and many manufacturers do not have a legitimate business license, resulting in the reproduction of plastic products when the temperature reaches 65 °C , poisonous substances will be precipitated and infiltrated into the food, it will cause damage to the liver, kidney, reproductive system and central nervous system and other important parts of the body.
Experts have found that almost all plastic products contain a large amount of plasticizers, and plasticizers are potentially harmful to the human body.
Plasticizers, called plasticizers in Taiwan, are plastic processing aids that are added to plastic polymers to increase plasticity. The most commonly used plasticizer is DEHP (Phthalic Acid Diester), which is mainly used in PVC (polyvinyl chloride) plastic products such as cling film, food packaging, toys, catheters, infusion bags and the like.
In the past, plasticizer compounds have been considered to be low in toxicity, have good physicochemical characteristics, and are easy to produce, inexpensive, and therefore are produced and used with almost no restrictions. At present, China has become a major producer of plasticizers, producing about 300,000 tons of plasticizers each year.
Researchers have found that the acute toxicity of plasticizers is very low, and that humans have almost no acute poisoning in a short period of time after ingestion, but this does not mean that it is safe. On the contrary, its chronic toxicity is quite harmful to the human body. Animal studies in foreign countries have shown that plasticizers can lead to decreased animal survival, weight loss, decreased liver and kidney function, reduced blood red blood cells, mutagenicity, and carcinogenicity.
According to experts, PVC products containing DOP (dioctyl phthalate) plasticizers are also widely used in human medical and life-related fields and are difficult to completely replace with other materials. Such as latex gloves, plasma bags, a part of blood transfusion, infusion, respiratory equipment, and children's toys, artificial leather (used as clothing, shoes, handbags, sofa fabrics, etc.), PVC products account for a large proportion. Some developed countries already have strict regulations or corresponding recommendations for plasticizers and other additives used in these products, while the main plasticizer for medical gloves and plasma bags in China is still DOP. What is even more worrying is that plasticizer contamination is almost everywhere, and the most commonly used raw materials in the chemical industry will slowly overflow from plastic products into air, soil, water and even food over time.
With the development of plasticizers and the increase in the scope of use, people are increasingly paying attention to their safety. Governments have begun to realize the potential threat of plasticizers to human health. For example, Denmark prohibits the use of phthalate plasticizers in plastics for infant toys and care products. Because young children mostly like to put toys in the mouth, plasticizers can harm children's health; Switzerland also prohibits the use of DOP in children's toys.
Although the way in which plasticizers are limited varies from country to country, two basic principles are followed: First, limit the amount of plasticizers used in plastics; second, limit the maximum amount of plasticizers that can be transferred into foods. Countries adopting the first principle include the United States, Germany, Britain, and Japan. The Netherlands, Italy, Spain, and other countries use the above two principles in combination.
China has also established a hygienic standard for the use of additives for food containers and packaging materials (GB9685-94), which regulates the variety, scope, and maximum use of additives for food containers and packaging materials, among which DBP (phthalate) The maximum allowable amounts of dibutyldicarboxylate) and DOP are 35% and 50%, respectively, but the maximum allowable content in foods has not been established.
To this end, some experts suggest that China's food industry should vigorously promote the reduction of the use of plastic packaging containers. In particular, it should avoid direct contact between plastic products and various foods and prevent plasticizers from contaminating food products. At the same time, we should increase investment in scientific research, conduct studies on the toxicity of plasticizers, and carry out prospective epidemiological investigations related to human health, and analyze and understand plasticizers from the levels of cells, molecules, and genes. Toxic, develop and develop better and safer alternative products in the field of polymers, and study related interventions.
