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Radioactivity And Its Effects The Chernobyl

Incident). Essay, Research Paper

RADIOACTIVITY AND ITS EFFECTS, (THE CHERNOBYL INCIDENT).

Some nuclei are radioactive, that is they spontaneously emit small particles, and high energy electromagnetic radiation, in doing so they form more stable nuclei. There are three different kinds of radiation, alpha, beta, and gamma. Quantitative studies have shown that alpha and beta are high enrgy particles, and gamma rays are very short high energy wavelengths (electro-magnetic radiation).

Radioactivity has benefitted man in various useful, ways like in medicine, providing nuclear power which can be used by humankind in various situations, but it also has its harmful effects, cause mutations in offspring if the mother is contaminated before birth cancer, and could also lead to evolutionary toxicology, in animals who received huge doses, and live in a radoiactive environment.

In the city of Pripyat, which is very close in proximity to Chernobyl, was once a thriving city, roaring, with forty five thousand people. On April 26, 1986, reactor four of the chernobyl power plant exploded due to flaws in the reactor s design and judgement errors by operators. The explosion belched out tons of radiation, ten times the amount of radiation relased by the atomic bomb dropped on Hiroshima in 1945 during world war two.. The radiation destroyed a lot of land (farm land), Soviet researchers noted steep declines in wild animals and die offs of small insects and worms living in the forest litter. * There was a lot of mutations too. The city of Pripyat is a ghost town, abandoned by its inhabitants, its surroundings are partly breathtaking .

Today much of the radioactivity has disappeared. Contaminants with short half lives such as radioiodine have completely decayed, and longer lived ones such as plutonim,and radiostrontium have settled deep into the ground. However high surface contaminants are still circulating in the food chain, and thus are contaminating the animals that eat the contaminated food, which leads to DNA mutation. Berries and mushrooms set the giger counters sreaming. Animals in the area have taken up radiostrontium in their bones and other radioactive materials into thier bodies and muscles.

The radiation breaks down chromosomes and the strands of the dna double helix,, which contain thew blueprints that make proteins for body. In most cases genetic damaged signals the cell to die a programmed death, or else it enlists repair enzymes to repair the genetic code. The problem arises in the repairing , because in almost all cases the codes are repaired incorrectly and they persist as mutations, which can lead to birth defects and cancer. Studies done on the mice at Chernobyl show , that they have many brekas in their dna strands, and a high mutation rate. Mice captured in the contaminated zone were compared to those living outside the zone ( in particular, their dna strands). The researchers read a gene callled cytochrome b , because it is passed directly from mother to offspring. The Chernobyl mice had gene sequenceas well as the proteins were different from the non – contaminated mice. Some mice are already paying a price by having a shorter life span, because of the radiatoin, and others are going through rapid evolution,(evolutionary toxicolgy). The rate of spontaneous mutations in mammalians has been estimated at one in a billion per generation, But at Chernobyl the mutation rate of the cytochrome b gene is 1 in 10, 000, this type of mutation is also occuring in other gene. This indicates that mammals are a lot more resilient to radioactivity than anyone ever guessed.

People from the region are clearly paying a heavy price for the accident, cancer and other disorders are on the increase. The rates of thyroid cancer in ukranian children have risen in recent years, in those that lived nearest to Chernobyl. Spontaneous abortions have also occured, birth defects have also been documented. Researchers expect a small increase in leukemias and other cancers. Though radioactivity does benefit us (I mean some of these people will actually use radiotherapy to try and get rid of their cancers), it also has major flaws, and safety cannot be guaranteed.




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