Nuclear Accidents Photo by: Maksim Nikalayenka Of all the environmental disaster events that humans are capable of causing, nuclear disasters have the greatest damage potential. The radiation release associated with a nuclear disaster poses significant acute and chronic risks in the immediate environs and chronic risk over a wide geographic area.
It can also cause sialadenitis an inflammation of the salivary glandgastrointestinal disturbances, allergic reactions and rashes. Potassium iodide is also not recommended for those who have had an allergic reaction to iodine, and people with dermatitis herpetiformis and hypocomplementemic vasculitis, conditions that are linked to a risk of iodine sensitivity.
Perchlorate ions, a common water contaminant in the USA due to the aerospace industryhas been shown to reduce iodine uptake and thus is classified as a goitrogen.
Perchlorate ions are a competitive inhibitor of the process by which iodide, is actively deposited into thyroid follicular cells. Studies involving healthy adult volunteers determined that at levels above 0. Perchlorate remains very useful as a single dose application in tests measuring the discharge of radioiodide accumulated in the thyroid as a result of many different disruptions in the further metabolism of iodide in the thyroid gland.
In another related study where subjects drank just 1 litre of perchlorate-containing water per day at a concentration of 10 ppm, i. Studies of chronically exposed workers though have thus far failed to detect any abnormalities of thyroid function, including the uptake of iodine. The continual addition of perchlorate to the water supply would need to continue for no less than 80—90 days, beginning immediately after the initial release of radioiodine is detected; after 80—90 days have passed, released radioactive iodine will have decayed to less than 0.
The ingestion of goitrogen drugs is, much like potassium iodidealso not without its dangers, such as hypothyroidism.
In all these cases however, despite the risks, the prophylaxis benefits of intervention with iodide, iodate, or perchlorate outweigh the serious cancer risk from radioiodine bioaccumulation in regions where radioiodine has sufficiently contaminatated the environment.
Medical use[ edit ] A pheochromocytoma tumor is seen as a dark sphere in the center of the body it is in the left adrenal gland.
Two images are seen of the same patient from front and back. The image of the thyroid in the neck is due to unwanted uptake of radioiodine as iodide by the thyroid, after breakdown of the radioactive iodine-containing medication.
Accumulation at the sides of the head is from salivary gland due to uptake of I mIBG by the sympathetic neuronal elements in the salivary glands. Meta-[I]iodobenzylguanidine is a radio-labeled analog of the adrenergic blocking agent guanethidine.
It is used in nuclear medicine therapeutically and can also be seen with diagnostic scanners if it has been used therapeutically.
Use of the I as iodide salt exploits the mechanism of absorption of iodine by the normal cells of the thyroid gland. Examples of its use in radiation therapy are those where tissue destruction is desired after iodine uptake by the tissue.
Major uses of I include the treatment of thyrotoxicosis hyperthyroidism and some types of thyroid cancer that absorb iodine. The I isotope is also used as a radioactive label for certain radiopharmaceuticals that can be used for therapy, e.
In all of these therapeutic uses, I destroys tissue by short-range beta radiation.
It can be seen in diagnostic scans after its use as therapy, because I is also a gamma-emitter. Instead the more purely gamma-emitting radioiodine iodine is used in diagnostic testing nuclear medicine scan of the thyroid. The longer half-lived iodine is also occasionally used when a longer half-life radioiodine is needed for diagnosis, and in brachytherapy treatment isotope confined in small seed-like metal capsuleswhere the low-energy gamma radiation without a beta component makes iodine useful.
The other radioisotopes of iodine are never used in brachytherapy. The use of I as a medical isotope has been blamed for a routine shipment of biosolids being rejected from crossing the Canada—U. Administration of therapeutic I[ edit ] Typical therapeutic doses of I are between megabecquerels MBq.
Administration of this liquid form is usually by straw which is used to slowly and carefully suck up the liquid from a shielded container. Such a precaution would essentially eliminate direct fetal exposure to radioactivity and markedly reduce the possibility of conception with sperm that might theoretically have been damaged by exposure to radioiodine.
Some also advise not to hug or hold children when the radiation is still high, and a one- or two- metre distance to others may be recommended.Decay & Half Life.
Why is this chapter on half-life being presented? The purpose of this chapter is to explain the process of radioactive decay and its relationship to the concept of half-life.
What is a pesticide half-life? A half-life is the time it takes for a certain amount of a pesticide to be reduced by half. This occurs as it dissipates or breaks down in the vetconnexx.com general, a pesticide will break down to 50% of the original amount after a single half-life.
The Man God Has For You: 7 traits to Help You Determine Your Life Partner [Stephan Labossiere, Stephan Speaks] on vetconnexx.com *FREE* shipping on qualifying offers. YOU DESERVE AN AMAZING MAN! So, where is he? Does he even exist? I can tell you that he does and that he is out there.
Iodine ( I) is an important radioisotope of iodine discovered by Glenn Seaborg and John Livingood in at the University of California, Berkeley. It has a radioactive decay half-life of about eight days. It is associated with nuclear energy, medical .
The Mid-Career Success Guide: Planning for the Second Half of Your Working Life [Sally J. Power] on vetconnexx.com *FREE* shipping on qualifying offers. Most people realize that the employment deal has changed: the days of lifetime employment, or even a clear trajectory up the corporate ladder.
Objective. For extended-release drugs with multi-compartment kinetics, such as topiramate, effective half-life (t 1/2eff) may be a more clinically relevant parameter than elimination half-life (t 1/2z).Using topiramate as a real-life example, the objective was to compare these half-life values for immediate- and extended-release topiramate (TPM-IR and USL, respectively) to understand how.