Ô NHIỄM TÁC VỀ CÁ GIỚI THIỆU Trong 25 năm qua, người đàn ông đã bị trái đất một loạt ngày càng tăng của các chất hóa học không bao giờ gặp phải trước khi các sinh vật sống. Nhiều người trong số các chất nước ngoài, có nguồn gốc từ các nguồn công nghiệp, nông nghiệp và, thành phố trực thuộc Trung ương, đe dọa nghiêm trọng các điều kiện môi trường tự nhiên được thành lập theo thời gian địa chất của các quá trình tiến hóa. Sinh vật, bao gồm con người, thấy nó càng khó khăn hơn. | POLLUTION EFFECTS ON FISH INTRODUCTION During the past twenty-five years man has subjected the earth to an ever increasing variety of chemical substances never before encountered by living organisms. Many of these foreign substances which originated from industrial agricultural and municipal sources are seriously threatening the natural environmental conditions established over geologic time by evolutionary processes. Organisms including man are finding it more and more difficult to escape the consequences of exposure to these compounds many of which are known to interfere with life sustaining biochemical and reproductive mechanisms. Little is known however concerning the effects the vast majority of these pollutants will have on plants and animals that inhabit this planet. The aquatic environment is the ultimate destination of most of these contaminants as a result of rainfall and runoff from the lands. The establishment of water quality requirements for the protection of fish life must therefore become an item of first priority. The task is complicated however by the fact that different species of fish as well as different developmental states of the same or different species exhibit wide variations in their sensitivity or tolerance to foreign materials. In addition the basic biochemical and physiological information needed to evaluate the harmful effects foreign substances have on organisms is severely lacking for fish and other aquatic organisms. It is the purpose of this chapter to briefly discuss the current state of knowledge in regard to the response of fishes to environmental contaminants. Because of the serious lack of information in the area of fish toxicology it is not possible nor is it within the scope of this discussion to present even an outline of the toxic effects of the many foreign substances which fish encounter. Instead representative compounds have been selected to illustrate the principles that are believed to play a major role in .
