Posts Tagged ‘nuclear reactions’

Science Makes Sense-Week 36: Chemistry and Social Justice-radiation, radium girls.

May 9, 2016

I remember when I was six or seven, my uncle came to visit us in the evening when we had a power cut in India and had no electricity. Everything turned pitch dark but I could see my uncle’s watch gleaming green in the dark! “Why is that happening? Do you have a magic watch?” I exclaimed. ” No magic, it is a glow-in-the-dark watch,” he responded. I was fascinated and learned years later that it was a radium watch. The dials had been painted with a salt containing radium.
Today we shall look closely at the discovery and use of one of the radioactive elements, radium (mention others in nuggets) and the terrible results of exposure due to ignorance and careless/negligent planning.
Radium was discovered by Pierre and Marie Curie in 1897 along with Polonium.(Ref.1) Pierre and Marie Curie were unaware of the dangers in the late 19th century/ early 20th century about nuclear reactions.
Most chemical reactions occur through transference/sharing of electrons, those very tiny particles that circle far away from the nucleus of an atom of any element. The nucleus is not touched in such reactions; however by the end of the 19th century, scientists were entering the realm of nuclear reactions. The nucleus is where the protons and neutrons are situated. The energy released when the nucleus is attacked, is several times that of a chemical reaction. Such attacks can be man-made as in nuclear reactors, and the explosion of atomic bombs, but radioactive elements that naturally decay can also cause nuclear reactions.
In fact Henri Becquerel was the first to observe mysterious radiation in uranium compounds and Maria and Pierre Curie did measurements on the amount of radiation emitted.(Ref.1) It is important to note that elements like technitium,Tc, prometheium, Pm as well as elements starting with polonium Po, all the way to the end of the Periodic Table exhibit radioactivity. In other words all the elements from atomic number 84 to atomic number 105 are radioactive, besides technitium and prometheium. Some of these elements are not too stable having very short half-lives.(Ref.2,3) Half life for an element is the time needed for half the mass of the element to decay.
The radioactive decay of elements leads to three kinds of ionizing radiation: alpha and beta particles as well as gamma radiation. Alpha particles consist of a pair of protons and neutrons, viz., it is a Helium ion. This is the least dangerous as far as radiation effects go, since they do not penetrate very deeply into clothing or skin. However, once ingested or inhaled through water or food sources, they could become carcinogenic and ultimately lead to lung cancer and other cancers. Beta particles are electrons that move very quickly; being 8000 times smaller than an alpha particle, this allows them to penetrate clothing and skin very easily. External exposure leads to burns and tissue damage and ingested/inhaled through water/food contamination could lead to serious health problems. Gamma rays are the most dangerous, these are fast-moving photons with no mass , passing easily through all body tissues and bone marrow causing extensive damage to the body and death based on amount/duration of exposure.(Ref.4)
While Marie and Pierre Curie may have been ignorant of the dangers of radium’s radioactivity, years later, many women were dangerously exposed to radium in U.S.factories where they were making radium watches and clocks. Referred to as the “radium girls” in Waterbury,Connecticut, Orange,New Jersey and in Ottawa, Illinois, young girls worked in factories and painted radium mixed as a paint with zinc sulfide, on dials of watches and clocks.(Ref.5) The managers, wanted them to lick the brushes so they were pointed to do the fine painting on the dials. Some of these girls even painted their buttons and finger nails to glow in the dark unaware of the terrible consequences. Initially because of ingesting alpha particles from the radioactive radium, they had terrible pains near the teeth and jaw, but eventually developed swelling and total destruction of the jaw and finally death in some cases. In Orange, new Jersey, 4 dial painters died and 8 were very ill. Dial painters there filed a suit in March of 1925 and following that workers no longer used their mouths to lick and point the brushes, they started wearing rubber gloves and use fume hoods after 1927. No more cases of cancers in dial painters were officially blamed on radiation. But the damage had been done.(Ref.5,6,7)
Years later, the suffering of the Radium girls led to safety measures for World War II atomic bomb workers.(Ref.5) Aah! But at what cost??
Activities for Middle School Teachers:
Teachers need to discuss how loosely and incorrectly certain words are used in daily life. The most common errors are made when the word ‘chemical’or ‘radiation’ is used, for example. All chemicals, radiation are considered harmful whereas water is also a chemical and electromagnetic radiation encompasses visible light. Let students research these words in science and understand the variation in meaning depending on context. Also, let students find other words in science that are mis-understood or partially explained by the non-scientific community.
Teachers should collaborate with Language Arts teachers and see if the word ‘synecdoche’ could be used to describe the incorrect usage of certain scientific words. (This word is a part of speech akin to a metaphor or simile; it means when a word is used to describe part of what it actually means)
Nuggets of Information:
Marie Curie’s notebooks and even her cookbook are so radioactively charged that they can only be viewed through lead screens today.(Ref.8)
Henri Becquerel received a burn carrying radium-rich barium chloride in his waist-pocket. Pierre Curie suggested that radium could be used for cancer therapy and in the 20’s it was used to treat some forms of skin cancer. In fact radium was touted as a cure for hypertension, diabetic pain, arthritis, gout and even for tuberculosis of the lung. Today, however radium is not used for any of this, but some research is underway to study its use to relieve intractable pain.(Ref.9)
Because of prolonged exposure to uranium, polonium and especially radium, Marie Curie succumbed to anemia related to radiation in bone marrow.(Ref.4)
The Geiger Counter was invented in 1928 and is used to measure radioactivity levels in many elements.(Ref.9)
It is important to note that all forms of radiation are not harmful to humans; e.g., electromagnetic radiation includes visible light. Also many man-made products like televisions,smart phones, microwave ovens emit radiation that are not dangerous and the danger varies with strength and length of exposure.(Ref.4)
There were 30 women in Connecticut, 35 women in Illinois and 41 women in New Jersey who died because of being dial painters (Radium Girls) in the 1920’s.(Ref.5)
Alexander Litvinenko, a former KGB officer died 3 weeks after ingesting a cup of tea containing Polonium 210.(Ref.8)
6.Clark, Claudia, Radium Girls,(University of North Carolina Press, 1997)
7.Mullner, Ross, Deadly Glow,( American Public Health Association, 1999)