‘Fascinating, And Kinda Scary’
(Disclosure: this was a proof copy given to me by the fine folks at No Alibis, for no good reason as far as I can tell other than they’re great people who like other people reading books. It’s not like they know me or know I write stuff here.)
This book is filled with lots of stuff I’d never even considered about light. I suppose that’s its purpose, and it does it very well.
What surprises me most is how recent some of the discoveries it describes are. The discovery of ‘heat rays’ - we now recognise as infrared radiation - was in 1800! Just over two centuries ago! And that’s light that’s only just invisible, just a bit beyond red. X rays and gamma rays are more recent still.
Other facts are more terrifying to me. Like the statement that CT scans kills one in every two thousand people getting a scan. One in every two thousand! 0.05% of people! Why is there not more of an outcry? Well, it’s partly because it’s not an immediate thing - the figure comes from people who die from a cancer they wouldn’t otherwise have had if not for the CT scan, so there’s possibly a long lag between cause and effect, and it’s hard to look at any specific case and say that particular cancer is because of that particular CT scan.
But still - one in every two thousand?
I couldn’t find a source online to point to for corroboration of that figure. Well, I could find lots of sources and lots of figures and I’m in no position to judge the credibility of those sources or of this book. Scientific American says:
Several years after the blasts, researchers began tracking rates of disease and death among more than 120,000 survivors. The results demonstrated, for the first time, that the cancer risk from radiation depends on the dose and that even very small doses can up the odds. Based on such data, a 2006 report from the National Research Council has estimated that exposure to 10 mSv—the approximate dose from a CT scan of the abdomen—increases the lifetime risk of developing any cancer by 0.1 percent. Using the same basic information, the U.S. Food and Drug Administration concluded that 10 mSv increases the risk of a fatal cancer by 0.05 percent. Because these risks are tiny compared with the natural incidence of cancer in the general population, they do not seem alarming. Any one person in the U.S. has a 20 percent chance of dying from cancer. Therefore, a single CT scan increases the average patient's risk of developing a fatal tumor from 20 to 20.05 percent.
And there are often good reasons to get a CT scan too - sometimes it’s life saving. Finding the balance must be really hard and I’m glad I’ve never been in that position.
Other facts from the book are less terrifying. UV radiation from sun exposure may be overhyped, so the advice there is get as much sun as you can without burning. That’s quite different from advice I’ve heard over the last few years. But again, I’ve no idea how much credibility to place in the book or in other sources.
Still, it certainly made me think!