Figure 1. Cobalt http://www.chemicool.com/elements/cobalt.html
Figure 2. Cobalt-60 radioisotope http://jonathanturley.org/2013/12/05/mexican-police-find-missing-containers-of-cobalt-60/
A very amazing opportunity to potentially save lives comes out of a career related to cobalt, and its radioisotope cobalt-60. With this element, radiation technicians are able to destroy cancer cells and tumors within sick cancer patients. This is ultimately the cure to cancer! I was given the task to research a career related to a single specific element and to prepare information on it. Radiation therapy is done by giving treatments of radiation onto a cancerous area, over a period of time in many treatments. The aim of this process is to kill the cancerous cells and to try to do as little damage as possible to the surrounding tissue. Radiation therapy has evolved much over the course of history.
Figure 3. Marie Curies radioactive notes http://www.chemistry-blog.com/2014/01/30/wellcome-chemical-images/
X-rays were first discovered by a German physicist named Wilhelm Roentgen in 1895. The x-rays produce radiation, and the first elements that were discovered to be radioactive were Polonium and Radium. They were discovered by Marie Curie, (Marie Sklodowska at the time) to give off a natural form of x-rays, known as gamma rays. These rays began to be used in medical studies at the time. One student in 1896, named Emil Grubbe noticed that when exposed to these rays, the skin on his hand began to peel he had blisters on his neck and hands. After further thinking, he hypothesized that these rays might be able to alleviate tumors. He convinced his professor to allow him to try his work on a cancer patient. The patients name was Rose Lee, and she was suffering from breast cancer. It showed signs of healing and decrease in tumor size. After doing this, Grubbe became the first ever Radiation Oncologist. For the longest time, radium was the most commonly used and effective radioactive element used for radiation therapy. In modern day radiation therapy, a synthetic radioisotope of cobalt is used to emit rays for radiation therapy. Cobalt-60 is more stable and safer than the other past used radioactive elements. Because of this, cobalt-60 is now used in most radiation therapy to help treat cancer patients.
Figure 5. Emil Grubbe http://www.jorhodeshomeopathy.co.uk/myths/like-cures-like/
Figure 4. Wilhelm Roentgen http://web.calstatela.edu/faculty/kaniol/f2000_lect_nuclphys/lect1/roentgen.htm
Radiation therapy is done over a long period of time with many treatments. The overall goal of it is to kill the cancerous cells or the tumor in the patient’s body. The more recent machines used in radiation therapy use cobalt-60 and use machines called a Co-60 unit. This machine is also called a teletherapy unit. These machines use Co-60 as the source of gamma radiation which they keep inside of
Figure 6. Co-60 teletherapy unit http://teachnuclear.ca/all-things-nuclear/other-nuclear-applications/medical-applications/cancer-therapy/
a steel capsule. The Co-60 unit has a patient support bench to position the patient exactly as needed for the specific treatment. It is very important to keep the same position every time that you get the treatment, because this allows for a more effective procedure with less radiation exposure to surrounding skin and tissue. On this unit is a primary beam is used as well as a collimator, which is a device used to narrow the beam to a more direct point, or to follow exactly what the radiation oncologist programs it to do to help reduce radiation exposure to the patient and the surrounding environment. Along with these pieces, a separate bunker has to be found so that the oncologist technician and radiation therapist can be shielded from radiation given off by the cobalt-60 gamma wave emission. These rays can be harmful to tissue and can cause symptoms such as; “gastrointestinal disturbances like diarrhea, vomiting, constipation, and abdominal pain” (rightdiagnosis.com). It can also give you neuropathy diseases, which is when there is a pathological change in the person’s mental state and causes numbness of limbs due to nerve damage. Some other symptoms are similar to the symptoms from radiation poisoning because that is what is happening.
Figure 7. Radiation tissue damage http://nevadahyperbarics.com/2012/08/hbot-helps-heal-damage-from-radiation/
Radiation therapy is an amazing ability to help many sick people, but it does come with some costs. When using radiation to damage and kill the cancerous cells, the radiation often comes in contact with healthy tissue and inflicts damage upon it. According to Cancer.net, some common side effects include fatigue as well as dry, itchy skin. If things such as irritable skin continue to occur, there is a chance that the doctor could change the treatment or the scheduling of the treatment. A more difficult side-effect to cope with is fatigue. With radiation therapy, it gives you a fatigue that is different than going to the gym or not getting enough sleep, it causes fatigue that cannot be removed by rest and sleep. The reason for this is that the patient’s body is working very hard with all of these extraneous treatments and their bodies don’t even get a break. One long term effect attached to radiation therapy is that there is a possibility of developing a second cancer due to the exposure to radiation that the patient’s bodies have endured. Having said this, this slim chance of a new cancer isn’t reason enough to not get radiation therapy to have the first cancer removed! Patients have a much higher chance of survival if they get their initial tumor removed, instead of concerning yourself with a potential second tumor. Another downside of cobalt-60 is the damage it does to the environment when it is not handled properly. The United States Government has controls on it, but sometimes the element unlawfully find its way to landfills and other areas where it becomes a problem. The U.S. EPA (Environmental Protection Agency) said that the cobalt-60 sometimes gets recycled inside of its metal container on accident, contaminating lots of money’s worth of melted metal with dangerous radioactive material. What happens when cobalt-60 gets into the environment is it undergoes radioactive decay, giving off gamma rays and spewing out beta particles that are harmful to the surrounding environment. Cobalt-60 has a half-life of 5.27 years, and a half-life is how long it takes for a radioactive element to lose half of its quantity from the beginning to the end of a time period. When it decays, it turns into the non-radioactive element, nickel. When a site has been contaminated with cobalt-60, it can take up to 10-20 years for the area to be non-radioactive and once again safe for use.
The new and exciting achievement of radiation therapy is internal radiation therapy, brachytherapy. This is the treatment of using a small holder of radiation and physically inside the patient, inserting it next to or inside the tumor itself. This will allow the patient to receive a higher dose in the areas that it is needed. This treatment has two main types; interacavitary where the radiation is placed in a body cavity like the rectum or the uterus, and interstitial where an implant is placed near the cancer but not thru a body cavity. In both of these types of brachytherapy they use implants such as pellets, seeds, ribbons, needles, capsules and other methods. This method and have less radiation spread to unwanted places, which is better for the patient and it also gives a higher dosage to the exact spot that needs the treatment.
Figure 8. Brachytherapy seeds http://www.upmcwhitfieldcancercentre.ie/Brachytherapy.htm
The electron configuration of cobalt is; 1s2,2s2,2p6,3s2,3p6,4s2,3d7. The simpler abbreviated configuration using a noble gas kernel is, [Ar] 3d74s2. Cobalt is located in group nine, period six on the modern periodic table. This region is also the “d” block, which has a “d” orbital. Cobalt has 2 valence electrons, which are the electrons on the outermost energy level, these are also the electrons that react with other atoms valence electrons. The first energy level has 2 electrons, the second has 8 electrons, but the third is strange because it has 15 electrons. This is weird because it does not conform to the octet rule, which is the rule that electrons try to gather eight electrons to fulfill an energy level, whether they have to get electrons or give them. Like I said above, there are 2 valence electrons. Cobalt-60 has the same number of electrons in the same place as cobalt-59, the difference is that cobalt-60 has an extra neutron. The number after Co, like 60, and 59 are the atomic mass of the atom. Atomic mass is the weight of all of the stuff in the nucleus, such as protons and neutrons. Scientists, like nuclear chemists have to add an extra neutron, which involves changing the stuff inside of the nucleus, therefore performing nuclear chemistry. So cobalt-59 has 27 protons and 32 neutrons, and this is the element found in nature. Cobalt-60 on the other hand has 27 protons and 33 neutrons, one more neutron than the natural cobalt-60.
Figure 9. Cobalt 60 electron arangement http://www.flw.com/datatools/periodic/002.php?id=60
I was handed the task of finding a career that is related to a specific element and to make notes and gather information on it and I feel that I have been successful in doing this. The element that I discovered was cobalt-60, a synthetic radioisotope of cobalt-59. This element is used in radiation therapy for being responsible for producing the gamma waves that are needed to kill the DNA of the cancerous cells in a sick person’s body. A Radiation Therapist is the person that is responsible for operating the machinery like the teletherapy (Co-60) unit and making sure that the helpful, yet possibly destructive, cobalt-60 is handled properly. This is the career that I researched.
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