Where do pesticides fit into the picture of environmental disease? We have seen that they now pollute soil,water and food, that they have the power to make our streams fishless and our gardens and woodlands silent and birdless. Man, however much he may like to pretend the contrary, is part of nature. Can he escape a pollution that is now so thoroughly distributed throughout our world:

　　We know that even single exposures to these chemicals, if the amount is large enough, can cause extremely severe poisoning. But this is not the major problem. The sudden illness or death of farmers, farmworkers, and others exposed to sufficient quantities of pesticides is very sad and should not occur. For the population as a whole, we must be more concerned with the delayed effects of absorbing small amounts of the pesticides that invisibly pollute our world.

　　Responsible public health officials have pointed out that the biological effects of chemicals are cumulative over long periods of time, and that the danger to individual may depend on the sum of the exposures received throughout his lifetime. For these very reasons the danger is easily ignored. It is human nature to shake off what may seem to us a threat of future disaster. "Men are naturally most impressed by diseases which have obvious signs, " says a wise physician, Dr Rene Dubos, "yet some of their worst enemies slowly approach them unnoticed."

　　練習(xí)題：

　　Choose correct answers to the question:

　　1.Which of the following is closest in meaning to the sentence "Man…is part of nature" (Para. 1, Lines 3-4)?

　　A. Man appears indifferent to what happens in nature.

　　B. Man acts as if he does not belong to nature.

　　C. Man can avoid the effects of environmental pollution.

　　D. Man can escape his responsibilities for environmental effects of pesticides?

　　2. What is the author"s attitude toward the environmental effects of pesticides?

　　A. Pessimistic

　　B. Indifferent

　　C. Defensive

　　D. Concerned

　　3. In the author"s view, the sudden death caused by exposure to large amounts of pesticides _____.

　　A. is not the worst of the negative consequences resulting from the use of pesticides

　　B. now occurs most frequently among all accidental deaths

　　C. has sharply increased so as to become the center of public attention

　　D. is unavoidable because people can"t do without pesticides in farming

　　4. People tend to ignore the delayed effects of exposure to chemical because _____.

　　A. limited exposure to them does little harm to people"s health

　　B. the present is more important for them than the future

　　C. the danger does not become apparent immediately

　　D. humans are capable of withstanding small amounts of poisoning

　　5. It can be concluded from Dr. Dubos remarks that _____.

　　A. people find invisible diseases difficult to deal with

　　B. attacks by hidden enemies tend to be fatal

　　C. diseases with obvious signs are easy to cure

　　D. people tend to overlook hidden dangers caused by pesticides

　　1.[B] 題干的句子是文章第1段第3句，這是一個帶有插入語的簡單句，contrary在此表示跟part of nature相反，因此答案為B。

　　2.[D] 第2段最后一句提到，我們必須更加關(guān)注吸收少量殺蟲劑的潛在后果，它們正在不知不覺地污染我們的世界。因此，作者對殺蟲劑對環(huán)境的影響關(guān)注且擔(dān)憂,D符合題意。

　　3.[A] 第2段第2句提到，殺蟲劑使人突然發(fā)病或者死亡是很令人難過的亊，對于人口整體來說，人類對殺蟲劑長期累計的潛在后果的認識不足，才是最嚴(yán)重的問題，故選A。

　　4.[C] 根據(jù)第3段倒數(shù)第2句說的“對未來的災(zāi)難無動于衷是人的本性”以及最后一句說的"大多數(shù)人只對有明顯跡象的疾病予以關(guān)注”可知C正是人們忽視化學(xué)藥物的潛在危害的原因，故選C。

　　5.[D] Dubos博士話中“最可怕的敵人”指的是“殺蟲劑引起的潛在危險”，博士話中的slowly approach them unnoticed直接表明D正確。