Arctic ice toxins are mostly artificial substances due to global warming
Famous photographer and marine environment expert Michael Nolan published a set of photos of the collapse of the Arctic glaciers in 2009. One of the photos called "The Crying Face" is thought-provoking. Experts described this as a desperate "mother of nature" silently protesting the melting of glaciers.
According to reports, this glacier is located in Norway near the Arctic, and belongs to Norway's largest ice sheet-Austfonna ice sheet. The latter is located in the Svalbard archipelago, with an area of ​​about 7,769 square kilometers. It is the second largest ice sheet in Europe and the seventh largest in the world.
â– Core tips
Recently, scientists have discovered that as the Arctic ice melts, toxins (persistent organic pollutants) that have been dormant under the Arctic ice begin to be released. Will the once sleeping toxins return to the world as the ice melts? Will humans face the double disaster of climate and toxins? How to resolve this potential "biochemical crisis"? The reporter interviewed experts on this.
Arctic "Pandora's Box" is opened by global warming
Liaoning Daily: A recent research report by scientists from Norway and Canada near the Arctic Circle shows that some toxins that were temporarily "frozen" are "seeing the sky" again as the Arctic ice melts, and "Pandora's Magic Box" is opening again. . Teacher Kuang, can you tell us what happened in the Arctic?
Kuang Yaoqiu: All right. At the Zeppelin Research Station in Svalbard, Norway and the Meteorological Warning Station in Northern Canada, researchers analyzed the persistent organic pollutant measurements that were tracked and detected over the past ten years and found that due to the impact of global warming Some of the toxins trapped in the Arctic ice are gradually being released as the ice melts.
Liaoning Daily: According to your knowledge, what toxins have been released?
Kuang Yaoqiu: These toxins include DDT, lindane (organochlorine pesticides), chlordane (agricultural pesticides), PCBs (used in transformers, capacitors, liquid-filled high-voltage cables, paints and plastics in industry), Hexachlorobenzene used for soil disinfection, etc.
Liaoning Daily: Most of these toxins sound artificial.
Kuang Yaoqiu: Yes, for example, DDT used to be an effective pesticide in the past. In the first half of the last century, people used it to prevent agricultural pests and diseases. However, the negative effects of persistent organic pollutant toxins such as DDT on humans and the natural environment are even greater. These substances are mainly divided into three categories: pesticides, industrial chemicals and by-products in production.
First, they have a long half-life and are resistant to photolysis, chemical decomposition, and biodegradation. Some substances will not be decomposed in water or even more than 2000 years. Secondly, they are generally semi-volatile materials, which can volatilize into the atmosphere at room temperature and can spread to a long distance through air flow and water flow. And these substances can also cause damage to organisms at low concentrations. The most terrible thing is that they have high lipophilicity and high hydrophobicity, can accumulate in the fat tissue of the organism, and pass through the food chain step by step, so that the concentration continues to increase when they gather to the human body at the top of the biochain In the meantime, the toxicity of some toxins can be magnified tens of thousands of times. The results of a study show that the concentration of DDT in seawater is 5.0 × 10-11g, while it is 4.0 × 10-8g in phytoplankton, 4.2 × 10-7g in clams, and 75.5 × in silver gulls. 10-6g. DDT has expanded a million-fold from the initial concentration to the final level of the food chain.
These toxins can cause disorders of the nervous system, immune system, reproductive system, and even cause cancer. Therefore, many countries and regions have already banned the use of such chemical substances.
Liaoning Daily: These toxins should be present in areas with frequent human activities. How could they go to the inaccessible Arctic?
Kuang Yaoqiu: Toxins appearing in the Arctic ice are the result of the combined effect of its own characteristics and atmospheric circulation.
As we said just now, POP toxins are persistent and semi-volatile, so they can enter the atmospheric environment from water or soil in the form of aerosols or be adsorbed on particulate matter in the atmosphere. Due to its persistence, it can migrate long distances in the atmospheric environment without being completely degraded, and its semi-volatility prevents them from permanently staying in the atmosphere, they will settle down under certain conditions, and then in certain Volatile under conditions. Repeating such volatilization and sedimentation multiple times can cause the persistent organic pollutant toxins to be dispersed everywhere on the planet.
The movement of the earth's atmosphere is driven by heat. The earth's equatorial and low-latitude regions receive more solar radiation, and the surface temperature is higher, which is easy to drive the atmosphere to produce upward movement. The surface temperature is low, and atmospheric movement is usually dominated by downdrafts. This creates an air circulation that rises in the equatorial and low latitude regions and falls in the polar and high latitude regions. With this air circulation, over time, semi-volatile toxins such as persistent organic pollutants will gradually migrate from the warmer equatorial and low-latitude regions to the colder polar and high-latitude regions. Persistent organic pollutants settled in the equatorial and low latitude areas will enter the atmospheric cycle again with the updraft, while persistent organic pollutants settled in the bipolar and high latitude areas will be enclosed in ice with snow, and It accumulates over time, so toxins such as persistent organic pollutants can also accumulate in places like the Arctic far away from pollution sources. It is believed that such toxins can also be found in the ice layer of Antarctica. (Author: Wang Liang)
Zhejiang Shengfa Textiles Printing&Dyeing.,ltd , https://www.chzjsf.com