Radium also gives off a small amount of gamma radiation, but the low levels of radium measured in Curie’s notebook give off equally low levels of gamma radiation. Radium primarily emits alpha radiation, which can’t even pass through a half-inch (about 1 cm) of air and cannot penetrate through the dead layer of skin cells of our epidermis to reach the living cells beneath. Were this to be ingested (perhaps by licking one’s fingers or transferring it to a sandwich), one might receive a dose equivalent to the same amount of exposure we receive from natural radiation in just two days. In reality, the likely radiation exposure from handling the diary is even lower – at most, about 0.0003 microCuries might be removed by holding the notebook. The bottom line is that this notebook doesn’t pose an appreciable risk to anybody who wants to read it – even if they do decide to lick the cover and pages. Having said that – do we expect that anybody is going to lick the front and back covers, or to eat, Marie Curie’s notebook? It seems unlikely – but even if they did, there’s not enough radioactivity to cause radiation sickness in the short term or create a significant risk of cancer in the long term. It’s more than I’d want someone to receive in a year, if only because we try not to let anybody exceed a radiation dose limit. Is this a lot of radiation exposure? Well…it depends on how you look at it. According to the Nuclear Regulatory Commission, a person can ingest up to 2 microCuries annually without exceeding a dose limit – this means that someone who decided to eat Marie Curie’s laboratory notebook would exceed their annual dose limit by about 60% for that year. Further analysis (and a little bit of calculation) showed that the notebook has about 1.6 microCuries of radium-226 on the covers and about twice this amount of activity through the entire notebook. In 2014 the Wellcome Trust commissioned an evaluation of contamination and radiation levels from Marie Curie’s notebook – the highest levels of contamination found were about 2500 counts per second (cps) of alpha contamination and 3500 cps of beta contamination. Scholars can handle the notebook, although the Christian Science Monitor tells us that they first need to sign a release and use gloves because of the contamination.īut before we make an appointment to see the notebooks, let’s talk about the risks! Oh – and if you’re interested, you can see Marie Curie’s notebook yourself – it’s in the Wellcome Collection (located in London), and anybody can download a scan as a PDF. Even less was known about good radiological work practices – it’s not surprising that the laboratory and notebooks became contaminated.Ĭonsidering radium’s 1600-year half-life and the sensitivity of today’s radiation detectors, it’s equally unsurprising that this contamination is still detectable today. They were doing this work only a few years after the discovery of radiation and radioactivity, and little was known of the potential harm they could cause. The reason for the concern is that Marie and Pierre Curie processed tons of uranium-bearing minerals in their laboratory, discovering the naturally radioactive elements polonium and radium through an arduous process of grinding tons of rock and painstakingly extracting the radioactive components. But that’s just my guess – luckily, there’s some information on the matter, so we don’t have to guess. And even more so when it’s radium that’s the contaminant – radium emits alpha particles (which can’t even penetrate through a piece of paper) and relatively low-energy gammas. But I’ve got to admit to being dubious – my background in radiation safety tells me that it’s not very easy to contaminate anything so much as to make it dangerous…especially through incidental contacts, such as writing or turning pages. So what’s the deal with Marie Curie’s laboratory notebooks? I recently read a question on an internet Q&A website asking how they can still be dangerous after a century and claiming that even touching the pages can put one at risk.
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