人事ではないので全国の高校生や大学生のみなさんに熟読してもらいたい。プラスチックの海洋汚染は人類の未来がかかった大問題なのである。
海に流出したプラスチックは海流に載って海洋渦に集まり、紫外線に当たって劣化しながら波の力でぶつかり合い、分解して微粒子になる。その微粒子に汚染物質とくっついた餌を海洋生物が食べる。
このままでは太平洋の真ん中で取れた魚もブラスチック微粒子で汚染され、食べられなくなる日が来る。いま行動しなければ、わたしたちが未来の子どもたちの食料を奪うことになる。
この問題は人類の遺伝子を劣化させるという点で、原子力発電所と共通の問題をはらんでいる。
（記事の後に、新聞に載っていた日本語での解説を転載してあります）
12月21日ジャパンタイムスより
http://www.japantimes.co.jp/opinion/2014/12/20/editorials/life-threatening-oceanic-plastic/
============================
If you're not sure how to activate it, please refer to this site: http://www.enable-javascript.com/
Editorials
Life-threatening oceanic plastic
A newly released study by scientific researchers finds that the problem of plastic in the ocean is worse than previously believed. The new highly extensive study published last month found that 5.25 trillion pieces of plastic weighing some 269,000 tons have now inundated the oceans, reaching into even the remotest areas.
The ships doing the research traveled far more widely than in past studies, collected more samples and used more advanced computer models to analyze the data. The conclusion confirms what has already been known: that the world’s oceans are full of plastic but that the new research indicates that the plastic has expanded and dispersed to a much greater degree than previously believed.
The study also examined how the plastic bottles, bags, toys and vast amount of other floating plastic gathers at “gyres,” where ocean currents come together into a massive circular eddy that traps the plastic. At those ocean gyres, the garbage is smashed together by wave action after becoming brittle in the sun. Once the plastic is shredded into pieces as small as grains of sand, it can spread widely.
As a result, researchers cannot easily determine where the smallest pieces have gone. One related study found 35,000 tons of plastic in the ocean, but they were expecting to find millions. The plastic didn’t disappear; it just became harder to find as it became more deeply enmeshed in the biosphere. Even more disturbing is the finding that plastic pieces easily become coated with other toxic substances such as PCBs, thereby helping to retain and spread the most poisonous substances. The toxic-coated, poisonous plastic is swept into the ocean’s deepest reaches to be ingested by marine organisms. After ingesting the pollutants and absorbing the toxic substances, the organisms pass them to predators higher in the food chain, where they become increasingly concentrated. Eventually, of course, that plastic reaches humans. Once the plastic enters the food chain, it doesn’t disappear. It works its way up.
The current use of plastic materials is ecologically unsustainable. Most estimates show that the vast majority of plastics used by consumers are not recovered or recycled. Plastic that makes its way into the ocean has little chance of ever being recycled. The increasing invasion of plastic into the food chain is not just a matter of sustainability; it is a matter of poisoning the source of all earthly life.
Solutions are difficult to come by. One suggestion is that fishing vessels reclaim nets and other plastic fishing equipment, since a great deal of the plastic comes from discarded fishing nets and buoys. It is not just the fishing industry that needs to institute better practices; the entire system of production and consumption of plastic in the world needs to be radically reformed. Controlling the level of plastic in the ocean is an urgent issue that must be addressed before humans start questioning each bite of fish they eat.
============================
新聞の解説欄から
------------------------------------------
●プラスチックによる海洋汚染
先月発売された研究結果によると、海には5兆個ものプラスチックごみがあふれており、総量は26万トンにのぼる。海洋渦に集まったプラスチックごみは波で砕かれて微粒子となり、汚染物質を吸着して拡散。それを食べた海洋生物をとおして生態系が汚染される。対策の一つは、漁船がブイや網を徹底回収することだ。さらに、世界中でプラスチックの生産と消費のシステムを見直すことが必要だ。海中のプラスチック量を抑制し、わたしたちが食べるたびに不安を感じることのないようにしたい。
------------------------------------------