Should seafood of period eat the nuclear pollution

Should seafood of period eat the nuclear pollution
Should seafood of period eat the nuclear pollution
At present, measure to elements such as radioactive iodine, cesium, hydrogen, xenon, krypton,etc. around Fukushima nuclear power station. Among them, half-life is relatively long, can spread to 100 That beyond k m distance is mainly radioactive iodine ( 1 3 1 I ) And radioactive cesium ( 1 3 7 C s ) . Though the masses ignorant of the fact are crazy robs iodized salt and iodine slice, can lead to the fact to the ecosystem the radioactive material of influence is not 131 me for a long time, but 137 C s - -8 in the former's half-life . 02 days, it can cause acutely to endanger in the surrounding area of the accident place, but totally decay 30 days later; And the latter's half-life reaches 3 0 . In 17, and can cause far-reaching influence as the rich collection of the food chain. The aquatic and biological one " Radiation is polluted " What is it? Let us review and cut the thing after happening of Pele's nuclear accident of the promise in spring of 1986: After the accident, a large number of 137 C s has entered the rivers and lakes around the nuclear power station. In first year after the accident, in those fish taking submarine piece or planktonic organism as food, miscellaneous feeding habits fish, the content of 137 C s is the highest. Subsequently, here 1 9 8 7 - 1 9 8 8 Annual, praying on fish (those fish taking other fish as food) 137 C s content of China begins to increase, it means 137 C s can transmit the food chain. 137 C s collects mainly and richly in the muscular tissue of the fish, other parts of the fish, for instance scale, digestive tract, gonad,etc. will absorb 137 C s too, but the density of these places will be apparent year by year reduced, 137 C s level in the muscle drops little. So, to radioactive element, the living beings collect function richly much more greatly than the question that the simple adsorption cause. The most serious situation: How having eaten and cut the promise Pele's fish? Researcher's measurement was cut in 1987 the shuttleless loom in Pele cooled pool of the nuclear power station of the promise kissed the perch (S a n d e r s p . ). It is a kind of praying on fish that the shuttleless loom kisses the perch, 137 C s content in their muscular tissue can be close at most 2 7 0 0 0 0 B q / k g (B q is Beckler, this is a unit which weighs radioactive activity) . Or in per kilogram of fish, per second to have 2 7 0 0 0 0 A piece of 137 C s atomic nucleus is in radioactive decay. �� and ��'s radiation energy that an 137 C s atom nuclear decay emits are probably 1. 174 M e V . (E V is electron-volt, kinetic energy of acquisition after accelerating a free electron through voltage of 1 volt. 1 M e V =1 . 602 * 10 ? 13 J ) Calculate briefly, if a weight 50 The person of k g, has eaten 1 K g such fish, the equivalent dosage of radiation that he will receive will be probably 3. 645 �� S v / h, only 3 per hour. 645 wishes a little, this intensity is probably 47 times (the radiation over Fukushima nuclear power station is 2 3 on the same day of the average radiation level in Beijing on March 15. 72 �� S v / h) . If compare this figure completely with the X-ray chest - -Accept X-ray chest once completely to check, the radiation dosage received is 50 �� S v - -It seems that the radiation that the chest receives is a lot bigger than to eat the fish. The question is, the chest is completely only the radiation dosage of once, but after the person eats that fish, know quilt radiation for a long time: Eat this 1 k g fish any more, the radiation intensity received has already exceeded and shone the chest once completely 24 hours later, if can't discharge these 137 C s (do not forget the rich collection of the food chain, it is reduced that 137 C s that the shuttleless loom will kiss in perch's muscles is not apparent in time ,Equivalent to will it be every day a few years the intersection of chest and one completely hereafter, 30 years in half-life in 137 C s. How great is the influence of the nuclear accident of Fukushima probably? A lot of people are saying " The promise Pele that it is cut that Fukushima will not become next " . Then, even if the intersection of Fukushima and nuclear accident have promise of cutting really Pele so loud influence, and how? If Fukushima nuclear power station can cause pollution to the water body, what it pollutes is mainly sea water. Because opening and dilute function of ocean, pollution that it receive can relatively light. Usually the most serious one is closing the water body pollution, such as the lake. Here 1 9 9 2 - 1 9 9 3 Annual, the research group of the Russian academy of sciences has compared several are cut cesium 137 C s content in the regional fresh-water fishes' muscular tissue of Pele's nuclear pollution of the promise, find the pollution that fish receive in the river is lighter than the fish in the lake, this obviously relates to degree of opening of the water body. In addition, the space distance reduces the important factor that 137 C s pollutes. We know in the cooled pool closest to nuclear power station, the shuttleless loom kisses the perch in the muscle the content of 137 C s can be reached 2 7 0 0 0 0 B q / k g, but in about 60 low reaches Kiev reservoir (K i e v outside k m R e s e r v o i r ) ,The shuttleless loom there kisses the perch in the muscle the content of 137 C s is about 100 at most B q / k g (1988) ,And then to the low reaches about 80 k m, the reservoir (K a n e v of alunite of card R e s e r v o i r ) The shuttleless loom of China kisses the perch in the muscle the content of 137 C s only reaches 20 B q / k g (1987) ,And 1989, World Health Organization (W H O) In the food security regulations drafted, the radioactive content international trade standard of the food including fish is 1000 B q / k g . Researchers still find, potassium content in the radioactive cesium and water in different river and fish muscular tissue of the lake is inverse ratio. Because cesium is mainly entered in the muscle as the element similar to potassium, the more potassium in water is, the less cesium in the fish is. In normal cases, the content of 137 C s is probably in the muscular tissue of fresh-water fishes of whole world 2 0 0 - 1 0 0 0 B q / k g, and this quantity is 0 in the ocean fishes. 4-3 . 3 B q / k g . High-load potassium to let the intersection of 137 C s and difficult rich reason that collect in the sea water. Having considered the worst situation, go back to look over the head, the polluting of nuclear accident of Fukushima perhaps can not reach and cut the intensity of the promise Pele at all. According to the latest news of Asahi Shimbun, the accident rank of the nuclear incident of Fukushima is 5 grades, the same as three island accident of U.S.A.. After the island accident of three, except little radioactive iodine(131 I in short term 1 . 51 B q / k g ) Pollute it beyond the local milk, does not almost have long-term environmental impact. It needn't worry about the affiliated sea area of China of the nuclear pollution to eat the seafood, from Fukushima first nuclear power station all in 1000 Beyond k m, add high-load potassium in the sea water, and the strong dilution ability of the whole Pacific Ocean, it worries to eat the domestic seafood From pollution of Fukushima. Certainly, eating the seafood has many other questions that is worth worrying about, we do not launch here Can see to stick to this global scientific and technological group of visiting group, after the accident of Fukushima, thick to work while being raw Japan province act as the strict regulation to radiation index in the the food, 137 C s content in the fish can't exceed 500 B q / k g - -This is half that W H O standard put a limit on quantity in 1989, and the food national standard in 1994 of our country was 800 B q / k g . If these standards can be well carried out, we needn't afraid at all either that from seafood of Japan that radiate the question.


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