2. 职称英语
  3. For the first time in the history of the world, every human being is now sub

For the first time in the history of the world, every human being is now sub

游客2023-12-28  29
问题     For the first time in the history of the world, every human being is now subjected to contact with dangerous chemicals, from the moment of conception until death. In the less than two decades of their use, the synthetic pesticides have been so thoroughly distributed throughout the animate and inanimate world that they occur virtually everywhere. They have been recovered from most of the major river systems and even from streams of groundwater flowing unseen through the earth. Residues of these chemicals linger in soil to which they may have been applied a dozen years before. They have entered and lodged in the bodies of fish, birds, reptiles, and domestic and wild animals so universally that scientists carrying on animal experiments find it almost impossible to locate subjects free from such contamination. They have been found in fish in remote mountain lakes, in earthworms burrowing in soil, in the eggs of birds — and in man himself. For these chemicals are now stored in the bodies of the vast majority of human beings, regardless of age. They occur in the mother’s milk, and probably in the tissues of the unborn child.
All this has come about because of the sudden rise and prodigious growth of an industry for the production of man-made or synthetic chemicals with insecticidal properties. This industry is a child of the Second World War. In the course of developing agents of chemical warfare, some of the chemicals created in the laboratory were found to be lethal to insects. The discovery did not come by chance: insects were widely used to test chemicals as agents of death for man.
The result has been a seemingly endless stream of synthetic insecticides.
    What sets the new synthetic insecticides apart is their enormous biological potency. They have immense power not merely to poison but to enter into the most vital processes of the body and change them in sinister and often deadly ways. Thus, as we shall see, they destroy the very enzymes whose function is to protect the body from harm, they block the oxidation processes from which the body receives its energy, they prevent the normal functioning of various organs, and they may initiate in certain cells the slow and irreversible change that leads to malignancy.
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答案     现在人类的每一个成员，从妊娠之初到寿终正寝，都在被迫接触危险的化学制品，在世界历史上还是头一次出现这种情况。在使用合成杀虫剂的不到20年的时间里，杀虫剂在生物界和非生物界广泛使用，结果弄得到处都是。各大水系大都含有这种杀虫剂，就连看不见的在地下流动的暗流里也能找到。这些化学制品可能是10多年前施用的，但至今仍有残余留在土壤里。这些化学制品广泛进入鱼、鸟、爬虫、家养的动物、野生动物，并停留在其体内，使得做动物实验的科学家要想找到未受污染的实验对象几乎是不可能的。已经发现这种化学制品存在于偏僻山间、湖泊里的鱼身上，存在于松土的蚯蚓身上，存在于鸟蛋里地——甚至存在于人身上。因为现在绝大多数人，不论年龄，体内都存有这种化学制品。母亲的乳汁里也有，未出世的婴儿的组织里可能也有。
    这些情况之所以产生，是因为一种产业突然出现并迅速发展，这一产业专门生产具有杀虫效力的人造或合成化学制品。这一产业是第二次世界大战的产物。在研制用于化学战的制剂的过程中，发现实验室里产生的某些化学品具有杀虫的作用。这也不是偶然发现的：为研制杀人制剂而进行的化学实验中曾广泛地使用昆虫。结果是各种合成杀虫剂似乎层出不穷。
    新的合成杀虫剂的特殊之处在于它们具有强大的生物功能。它们的能量很大，不但能释放毒性，还能进入肌体内最重要的过程，并使之发生有害的，而且往往是致命的变化。就这样，我们将会看到，它们能破坏酶，而酶的功能是保护肌体免受伤害；它们能阻碍氧化作用，而氧化作用是肌体获得能量的源泉；它们能妨害各个器官正常发挥作用；它们还可能在某些细胞里引起缓慢的无法恢复的变化，最终导致癌变。
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