Ripercussioni sanitarie in caso di disastro nucleare
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Non abbiamo ancora dati precisi sul danno ecologico di tipo nucleare del disastro giapponese causato dal maremoto dell’11 marzo 2011, perché ogni centrale nucleare ha anche caratteristiche proprie. Sappiamo però che in Giappone è immediatamente scattata la raccomandazione di assumere dello iodio per saturare la tiroide e questo ci riporta alla tragica esperienza del disastro di Chernobyl (Biolorussia) del 26 aprile 1986.
Per quello che sappiamo finora, seems that the explosion at Chernobyl was the most environmentally damaging of the Japanese and Italians are also protected by the considerable distance that separates us from Japan.
In any case, we can make some general considerations that still apply in these situations :
a) The leakage of radioactive substances (radioisotopes) does not happen all at once at the time of the explosion, but is extended over time as gas, vapor and dust.
b) The principal radionuclides released, and in particular among those who know best for their biological effect on living organisms, attention should be essentially the radioisotopes of iodine (131-I 132-I, 134-I, 135-I), del cesio (134-Cs, 137-Cs) e dello stronzio (89-Sr, 90-Sr), anche se non vanno dimenticati i radionuclidi del plutonio (238-Pu, 239-Pu, 240-Pu) e dell’uranio e i gas radioattivi e altamente tossici di xenon (133-Xe) e kripton (85-Kr).
c) I radioisotopi dello iodio vengono assorbiti prevalentemente per via alimentare e concentrati dalla tiroide, mentre lo stronzio entra nella composizione delle ossa e il cesio, dato che segue le vie metaboliche del potassio, viene facilmente eliminato con le urine.
d) L’emivita di queste sostanze (cioè il tempo in cui la loro radioattività di dimezza o, meglio ancora, il tempo che deve trascorrere affinché la metà dei nuclei of a given radionuclide will experience decay) depends on the substance in question and in particular:
The data emerged from the explosion of Chernobyl, it appears that the main contribution to the radioactivity is due to iodine. Therefore, given that the thyroid uses iodine to produce thyroid hormones, is the organ most affected by late effects of a nuclear explosion.
The greatest risk: the thyroid cancer
The thyroid needs iodine to synthesize thyroid hormones, and assumes mineral nutrition (and to a lesser extent with respiration). As in many countries (including Italy) iodine is poorly available in food and beverages, thyroid is especially hungry for iodine, and then builds up rapidly as soon as it receives from the blood. So when a nuclear explosion releases large amounts of radioisotopes of iodine, they pollute the environment (air, water, earth and therefore food), we eat with them and feeding them after reaching the blood, are accumulated by thyroid where they are concentrated in high doses. In the thyroid, therefore, they exercise their most inflammatory changes causing biological damage, autoimmune diseases and even cancer.
The thyroid gland accumulates a quantity of radioactive iodine is inversely proportional to its mass and therefore smaller thyroids (Such as children) accumulate more radioactive iodine thyroid large (adult). In fact, after the Chernobyl accident, children (especially those under 6 years old and over again, or even those infants present still in the womb at the time of the nuclear disaster) showed an increased number of thyroid cancer than adults.
The average latency period between radiation exposure and the diagnosis of thyroid disease is about 4-5 years. The most frequent childhood thyroid cancer caused by a nuclear disaster are papillary carcinomas, while the state is the pre-cancerous dall'iperplasia micropapillary.
thyroid tumors arising due a nuclear pollution are much more aggressive than spontaneous onset (tumors of the thyroid induced by the explosion of the Chernobyl reactor showed extrathyroidal invasion already at diagnosis in 49.1% of cases, compared to 24.9% of cases of similar tumors seen in other nuclear countries not polluted by radioactivity).
How to protect the thyroid in the event of nuclear disaster?
You can certainly do much, except to try to get as far away as possible and as soon as possible while removed from the contaminated area for at least several months. If this is not completely possible, or if you need to bear in areas at risk, the Board is to take an appropriate dose to take iodine saturated thyroid cells by preventing them from picking up more iodine, and then radioactive iodine. The advantage of iodine is its fast action that allows for effective action by blockage of thyroid iodine again soon.
In adults, iodine is administered as a saturated solution of potassium iodide or as Lugol's solution 5% (1 drop = 8 mg of iodine, 5 drops 3 times a day). For children
evacuated from the Chernobyl area were instead given the following doses of potassium iodide:
- children aged 1-3 years: 0.5 mg every 15 days;
- Children 4-7 years: 0.5 mg every week;
- children aged 8 years and older: 1 mg per week.
studies in the literature state that the intake of potassium iodide is associated with a significant reduction in the risk of future thyroid cancer by radioactive substances.
Dr. Roberto Gava
Pharmacology, toxicology
Bibliography
1) Tronk MD, Howe GR, Bogdanova TI, Bouville AC et al. A cohort study of thyroid cancer and other thyroid diseases after the Chernobyl accident: thyroid cancer in Ukraine During first screening detected . Journal of the National Cancer Institute 2006; 98 (13): 897-903.
2) http://www.fisicamente.net/DIDATTICA/index-1089.htm.
3) http://www.arca-onlus.it/Pagine/Chernobyl/conseguenze2.asp.
4) Heidenreich WF, Kenigsberg J, Jacob P, Buglova E, Goulko G, Paretzke HG, et al. Time trends of thyroid cancer incidence in Belarus after the Chernobyl accident . Radiat Res 1999;151:617–25.
5) Cardis E, Kesminiene A, Ivanov V, Malakhova I, Shibata Y, Khrouch V, et al. Risk of thyroid cancer after exposure to 131I in childhood . J Natl Cancer Inst 2005;97:724–32.
6) Astakhova LN, ed. Children’s thyroid gland: consequences of the Chernobyl accident [in Russian]. Ministry of Public Health of Belarus, Minsk, 1996.
http://www.informasalus.it/it/articoli/ripercussioni-sanitarie-disastro-nucleare.php
In any case, we can make some general considerations that still apply in these situations :
a) The leakage of radioactive substances (radioisotopes) does not happen all at once at the time of the explosion, but is extended over time as gas, vapor and dust.
b) The principal radionuclides released, and in particular among those who know best for their biological effect on living organisms, attention should be essentially the radioisotopes of iodine (131-I 132-I, 134-I, 135-I), del cesio (134-Cs, 137-Cs) e dello stronzio (89-Sr, 90-Sr), anche se non vanno dimenticati i radionuclidi del plutonio (238-Pu, 239-Pu, 240-Pu) e dell’uranio e i gas radioattivi e altamente tossici di xenon (133-Xe) e kripton (85-Kr).
c) I radioisotopi dello iodio vengono assorbiti prevalentemente per via alimentare e concentrati dalla tiroide, mentre lo stronzio entra nella composizione delle ossa e il cesio, dato che segue le vie metaboliche del potassio, viene facilmente eliminato con le urine.
d) L’emivita di queste sostanze (cioè il tempo in cui la loro radioattività di dimezza o, meglio ancora, il tempo che deve trascorrere affinché la metà dei nuclei of a given radionuclide will experience decay) depends on the substance in question and in particular:
The data emerged from the explosion of Chernobyl, it appears that the main contribution to the radioactivity is due to iodine. Therefore, given that the thyroid uses iodine to produce thyroid hormones, is the organ most affected by late effects of a nuclear explosion.
The greatest risk: the thyroid cancer
The thyroid needs iodine to synthesize thyroid hormones, and assumes mineral nutrition (and to a lesser extent with respiration). As in many countries (including Italy) iodine is poorly available in food and beverages, thyroid is especially hungry for iodine, and then builds up rapidly as soon as it receives from the blood. So when a nuclear explosion releases large amounts of radioisotopes of iodine, they pollute the environment (air, water, earth and therefore food), we eat with them and feeding them after reaching the blood, are accumulated by thyroid where they are concentrated in high doses. In the thyroid, therefore, they exercise their most inflammatory changes causing biological damage, autoimmune diseases and even cancer.
The thyroid gland accumulates a quantity of radioactive iodine is inversely proportional to its mass and therefore smaller thyroids (Such as children) accumulate more radioactive iodine thyroid large (adult). In fact, after the Chernobyl accident, children (especially those under 6 years old and over again, or even those infants present still in the womb at the time of the nuclear disaster) showed an increased number of thyroid cancer than adults.
The average latency period between radiation exposure and the diagnosis of thyroid disease is about 4-5 years. The most frequent childhood thyroid cancer caused by a nuclear disaster are papillary carcinomas, while the state is the pre-cancerous dall'iperplasia micropapillary.
thyroid tumors arising due a nuclear pollution are much more aggressive than spontaneous onset (tumors of the thyroid induced by the explosion of the Chernobyl reactor showed extrathyroidal invasion already at diagnosis in 49.1% of cases, compared to 24.9% of cases of similar tumors seen in other nuclear countries not polluted by radioactivity).
How to protect the thyroid in the event of nuclear disaster?
You can certainly do much, except to try to get as far away as possible and as soon as possible while removed from the contaminated area for at least several months. If this is not completely possible, or if you need to bear in areas at risk, the Board is to take an appropriate dose to take iodine saturated thyroid cells by preventing them from picking up more iodine, and then radioactive iodine. The advantage of iodine is its fast action that allows for effective action by blockage of thyroid iodine again soon.
In adults, iodine is administered as a saturated solution of potassium iodide or as Lugol's solution 5% (1 drop = 8 mg of iodine, 5 drops 3 times a day). For children
evacuated from the Chernobyl area were instead given the following doses of potassium iodide:
- children aged 1-3 years: 0.5 mg every 15 days;
- Children 4-7 years: 0.5 mg every week;
- children aged 8 years and older: 1 mg per week.
studies in the literature state that the intake of potassium iodide is associated with a significant reduction in the risk of future thyroid cancer by radioactive substances.
Dr. Roberto Gava
Pharmacology, toxicology
Bibliography
1) Tronk MD, Howe GR, Bogdanova TI, Bouville AC et al. A cohort study of thyroid cancer and other thyroid diseases after the Chernobyl accident: thyroid cancer in Ukraine During first screening detected . Journal of the National Cancer Institute 2006; 98 (13): 897-903.
2) http://www.fisicamente.net/DIDATTICA/index-1089.htm.
3) http://www.arca-onlus.it/Pagine/Chernobyl/conseguenze2.asp.
4) Heidenreich WF, Kenigsberg J, Jacob P, Buglova E, Goulko G, Paretzke HG, et al. Time trends of thyroid cancer incidence in Belarus after the Chernobyl accident . Radiat Res 1999;151:617–25.
5) Cardis E, Kesminiene A, Ivanov V, Malakhova I, Shibata Y, Khrouch V, et al. Risk of thyroid cancer after exposure to 131I in childhood . J Natl Cancer Inst 2005;97:724–32.
6) Astakhova LN, ed. Children’s thyroid gland: consequences of the Chernobyl accident [in Russian]. Ministry of Public Health of Belarus, Minsk, 1996.
http://www.informasalus.it/it/articoli/ripercussioni-sanitarie-disastro-nucleare.php
of Roberto Gava - Informasalus
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