Editing Radium (section)

====Luminescent paint====
[[File:Radium 2.jpg|thumb|Watch hands coated with radium paint under ultraviolet light]]
Radium was formerly used in [[luminescence|self-luminous]] paints for watches, aircraft switches, clocks, and instrument dials and panels. A typical self-luminous watch that uses radium paint contains around 1 microgram of radium.<ref name=renamed_from_2024184_on_20240813160145/> In the mid-1920s, a lawsuit was filed against the [[United States Radium Corporation]] by five dying "[[Radium Girls]]" – dial painters who had painted radium-based [[luminous paint]] on the components of watches and clocks.<ref name=":2" /> The dial painters were instructed to lick their brushes to give them a fine point, thereby ingesting radium.<ref name=OakRidge>
{{cite web
 | author = Frame, Paul
 | year = 1999
 | title = Radioluminescent paint
 | website = Museum of Radiation and Radioactivity
 | publisher = [[Oak Ridge Associated Universities]]
 | url = https://www.orau.org/health-physics-museum/collection/radioluminescent/index.html#section-heading-main
 | archive-date = July 31, 2014
 | archive-url = https://web.archive.org/web/20140731220027/http://www.orau.org/ptp/collection/radioluminescent/radioluminescentinfo.htm
 | url-status = live
}}
</ref> Their exposure to radium caused serious health effects which included sores, [[anemia]], and [[bone cancer]].<ref name=epa/>

During the litigation, it was determined that the company's scientists and management had taken considerable precautions to protect themselves from the effects of radiation, but it did not seem to protect their employees. Additionally, for several years the companies had attempted to cover up the effects and avoid liability by insisting that the Radium Girls were instead suffering from [[syphilis]].<ref>{{cite web|url=http://environmentalhistory.org/people/radiumgirls/|title=Environmental history timeline&nbsp;– Radium Girls|access-date=1 Sep 2018|date=2012-07-20|archive-url=https://web.archive.org/web/20180902084212/http://environmentalhistory.org/people/radiumgirls/|archive-date=2 September 2018|url-status=live}}</ref>

As a result of the lawsuit, and an extensive study by the U.S. Public Health Service, the adverse effects of radioactivity became widely known, and radium-dial painters were instructed in proper safety precautions and provided with protective gear. Radium continued to be used in dials, especially in manufacturing during [[World War II]], but from 1925 onward there were no further injuries to dial painters.
<ref name=":2">{{multiref2|Rowland, R. E. (1995) [https://publications.anl.gov/anlpubs/1994/11/16311.pdf Radium in humans: a review of U.S. studies] {{Webarchive|url=https://web.archive.org/web/20111109003623/http://www.osti.gov/accomplishments/documents/fullText/ACC0029.pdf |date=9 November 2011 }}. Argonne National Laboratory. p. 22|{{Cite journal |last=Coursey |first=Bert M. |date=2021 |title=The National Bureau of Standards and the Radium Dial Painters |url=https://nvlpubs.nist.gov/nistpubs/jres/126/jres.126.051.pdf |journal=Journal of Research of the National Institute of Standards and Technology |language=en |volume=126 |doi=10.6028/jres.126.051 |issn=2165-7254 |pmc=10046820 |pmid=38469446}}}}</ref>

From the 1960s the use of radium paint was discontinued. In many cases luminous dials were implemented with non-radioactive fluorescent materials excited by light; such devices glow in the dark after exposure to light, but the glow fades.<ref name="epa" /> Where long-lasting self-luminosity in darkness was required, safer radioactive [[promethium]]-147 (half-life 2.6 years) or [[tritium]] (half-life 12 years) paint was used; both continue to be used as of 2018.<ref>{{multiref2|{{Cite journal |last1=Broderick |first1=Kathleen |last2=Lusk |first2=Rita |last3=Hinderer |first3=James |last4=Griswold |first4=Justin |last5=Boll |first5=Rose |last6=Garland |first6=Marc |last7=Heilbronn |first7=Lawrence |last8=Mirzadeh |first8=Saed |date=February 2019 |title=Reactor production of promethium-147 |url=https://linkinghub.elsevier.com/retrieve/pii/S0969804318305931 |journal=Applied Radiation and Isotopes |language=en |volume=144 |pages=54–63 |doi=10.1016/j.apradiso.2018.10.025|pmid=30529496 |bibcode=2019AppRI.144...54B }}|{{Cite journal |last1=Eyrolle |first1=Frédérique |last2=Ducros |first2=Loïc |last3=Le Dizès |first3=Séverine |last4=Beaugelin-Seiller |first4=Karine |last5=Charmasson |first5=Sabine |last6=Boyer |first6=Patrick |last7=Cossonnet |first7=Catherine |date=January 2018 |title=An updated review on tritium in the environment |url=https://linkinghub.elsevier.com/retrieve/pii/S0265931X17307956 |journal=Journal of Environmental Radioactivity |language=en |volume=181 |pages=128–137 |doi=10.1016/j.jenvrad.2017.11.001|pmid=29149670 |bibcode=2018JEnvR.181..128E }}}}</ref> These had the added advantage of not degrading the phosphor over time, unlike radium.<ref>{{cite book |script-title=ru:Аналитическая химия технеция, прометия, астатина и франция |trans-title=Analytical Chemistry of Technetium, Promethium, Astatine, and Francium |language=ru |first1=Avgusta Konstantinovna |last1=Lavrukhina |first2=Aleksandr Aleksandrovich |last2=Pozdnyakov |date=1966 |publisher=[[Nauka (publisher)|Nauka]] |page=118}}</ref> Tritium as it is used in these applications is considered safer than radium,<ref name="ieer">{{cite web|author=Zerriffi, Hisham|date=January 1996|title=Tritium: The environmental, health, budgetary, and strategic effects of the Department of Energy's decision to produce tritium|url=http://www.ieer.org/reports/tritium.html#(11)|publisher=[[Institute for Energy and Environmental Research]]|access-date=15 September 2010|archive-url=https://web.archive.org/web/20100713051055/http://www.ieer.org/reports/tritium.html#(11)|archive-date=13 July 2010|url-status=live}}</ref> as it emits very low-energy [[beta radiation]]<ref>{{Cite web |title=Physical and Chemical Properties of Tritium |url=https://www.nrc.gov/docs/ML2034/ML20343A210.pdf |access-date=25 October 2024 |website=Nuclear Regulatory Commission}}</ref> (even lower-energy than the beta radiation emitted by promethium)<ref>{{Cite thesis |last=Hinderer |first=James Howard |title=Radioisotopic Impurities in Promethium-147 Produced at the ORNL High Flux Isotope Reactor |date=2010 |degree=Master's |publisher=University of Tennessee |url=https://trace.tennessee.edu/utk_gradthes/717}}</ref> which cannot penetrate the skin,<ref>
{{cite report
 |title=Hydrogen-3
 |series=Nuclide safety data sheet
 |publisher=Environmental Health & Safety Office, [[Emory University]]
 |via=ehso.emory.edu
 |url=http://www.ehso.emory.edu/content-forms/3anuclidedatasafetysheets.pdf   <!-- presumed -->
 |archive-url=https://web.archive.org/web/20130520184942/http://www.ehso.emory.edu/content-forms/3anuclidedatasafetysheets.pdf
 |archive-date=2013-05-20  }}
</ref> unlike the gamma radiation emitted by radium isotopes.<ref name="ieer" />
[[File:WWI German altimeter radium painted.jpg|thumb|left|A zeppelin [[altimeter]] from [[World War I]]. The dial, previously painted with a luminescent radium paint, has turned yellow due to the degradation of the fluorescent [[zinc sulfide]] medium.]]
Clocks, watches, and instruments dating from the first half of the 20th century, often in military applications, may have been painted with radioactive luminous paint. They are usually no longer luminous; this is not due to radioactive decay of the radium (which has a half-life of 1600&nbsp;years) but to the fluorescence of the zinc sulfide fluorescent medium being worn out by the radiation from the radium.{{sfn|Emsley|2003|page=351}} 
Originally appearing as white, most radium paint from before the 1960s has tarnished to yellow over time. The radiation dose from an intact device is usually only a hazard when many devices are grouped together or if the device is disassembled or tampered with.<ref>{{Cite web |last= |first= |date=2024-05-27 |title=Could your collectible item contain radium? |url=https://www.cnsc-ccsn.gc.ca/eng/resources/radiation/could-your-collectible-item-contain-radium/ |access-date=2024-10-22 |website=Canadian Nuclear Safety Commission}}</ref>