QI. Image shows from L to R: Alan Davies, Sandi Toksvig. Copyright: TalkbackThames.


BBC Two and BBC One panel show about quite interesting facts. 266 episodes (pilot + 18 series), 2003 - 2020. Stars Sandi Toksvig, Stephen Fry and Alan Davies.

Returns Wednesday 23rd December at 9pm. Episode Guide
Series P, Episode 2 is repeated on Dave today at 9pm.

QI. Image shows from L to R: Josh Widdicombe, Alan Davies, Sandi Toksvig, Shazia Mirza, Joe Lycett.

Series R, Episode 9 - Radioactive

Sandi Toksvig asks questions on the theme of radio this week, with Joe Lycett, Shazia Mirza, Josh Widdicombe and Alan Davies trying to come up with interesting answers - while avoiding the most obvious ones.

Further details


- The member of the panel who encountered a lot of radioactive material as a child is Josh. He comes from Dartmoor, and houses there have radon detectors. The middle of Dartmoor is the worst place in the country for radon. In the UK, most radiation that the public receives comes from radon and thoron gases. Meanwhile Birmingham, where Shazia and Joe come from, is an island of low radiation. Essex, where Alan is from, is also low risk. The reason why Dartmoor has such high levels of radiation is because the ground rock is mostly granite, which contains small amounts of uranium, which decays and produces radon. You can be exposed to as much as seven millisieverts of radiation per year in Dartmoor, the same as a CT scan, 85 transatlantic flights, or 70kg of Brazil nuts (the nuts contain lots of radon because the plants have deep roots).

- Tangent: Josh and his family would go on canal holidays to Birmingham. His father said that Birmingham was best for a canal holiday because it has more canals than Venice, which implies that he at least considered Venice.

- XL Tangent: Joe had his kitchen extension opened by the Lord Mayor of Birmingham. Joe asked her if she would, but she said no because she doesn't do private events. Joe thus made it a public event, sold tickets to the public, and the Lord Mayor then agreed to do a ribbon cutting ceremony, unveiling a plaque of the event.

- XL Tangent: Austria has one nuclear plant, built in 1978, but it was never used as a power plant. After the plant was finished the country passed a referendum to not open it. The plant is now used as a research centre.

- One of the ways to sell a house right next to a nuclear power plant is for the publicity photo of the house to be taken without the plant in shot. In 2009, three-bedroom cottage in Kent was advertised with photo as if the house was away from anywhere, but the estate agent failed to mention that if you stood behind the house you would see that the cottage is just 100 yards away from Dungeness Nuclear Power Station, one of Europe's largest nuclear power stations. When asked about it, the estate agent said: "The thing is, anywhere on Dungeness is close to the power station."

- The ray that changed the world of fashion forever was x-rays. In the mid 19th-century, women wore heavily boned corsetry, some having more than 100 whalebones, and there was concern about how these corsets affected the health of women. In 1908, French doctor Ludovic O'Followell took x-ray photos of women in corsets and wrote a book called Le Corset which showed the women's ribs were being displaced by Victorian corsets. Thanks to his work, fashions changed.

- Tangent: X-rays were discovered by Wilhelm Conrad Roentgen. The first x-ray he took in 1895 was of his wife's hand, which showed both the bones in her hand and her wedding ring. When Mrs. Roentgen first saw the photo she said: "I have seen my death." Roentgen won the first-ever Nobel Prize in physics. X-rays, still called Roentgen rays in Denmark, sparked a "Roentgen mania", with 50 books published on x-rays in a single year, plays were themed on x-rays, newspapers advertised x-ray-proof underwear for women, and Thomas Edison created a "fluoroscope" where you could see your bones on screen. However, the following year they discovered just how dangerous x-rays were, with 23 cases of severe x-ray injury being reported in scientific journals, but despite this x-rays were being used for decades to cure illnesses including cancer, tuberculosis, acne and ringworm. They said x-rays could remove unwanted body hair, which it did, but it also left patients ulcerated and bedridden.

- Tangent: The panel comment that the ring in the first x-ray looks like an Oreo, leading to Alan to say that he finds it irritating when children take apart an Oreo or Bourbon to eat it. Josh says the problem might with Alan rather than his children.

- XL Tangent: One scientist claimed that he could make dogs salivate by projecting an image of a bone into its brain using X-rays, but this was false. Between the 1930s and 1970s, a machine called a pedoscope used X-rays measure shoe sizes, and you could use it while you still wearing your shoes. However, you could only have 12 shoe fittings a year because it affected the shop staff too much. Josh remembers in his youth a machine that measured foot sizes by using robotic moving plates.

- XL: A question on radiology. The panel are shown a scan and are asked if they can see anything unusual in it. The unusual thing in it is that a picture of a man in a gorilla suit has been inserted into it. This was a test created by researchers at Harvard Medical School, who deliberately inserted pictures of gorillas into people's scans, to see if trained radiologists would notice it. They were missed 83% of the time. The gorilla was used in homage to a study created by two psychologist from the University of Illinois, who created a film of people bouncing basketballs to each other and you are told to count how many times the balls are bounced, but while all this is going on a man in a gorilla suit walks past and waves. Most people watching the clip fail to notice the gorilla. This is known as "inattentional bias", where people miss obvious things when looking for something specific.

- XL Tangent: Pigeons may be able to spot the gorilla. An experiment by the University of Iowa trained pigeons to spot diseases in scans. The results show that pigeons have pretty much the same skill at spotting diseases as humans. They put 16 pigeons in boxes, and they were trained to peck on blue rectangles if they spotted healthy tissue and yellow rectangles if they spotted malignant tissue. If the pigeons were right, they were rewarded. When fully trained, the pigeons could detect the difference between normal and cancerous slides at pretty much the same extent as humans. Pigeons were right on 84% of images they were trained on, and 72% right on images they had never seen before. However, pigeon brains are no larger than a hazelnut. If you took the responses of four birds and combine them, in an act known as "flock sourcing", they are accurate 99% of the time.

- The defining characteristic of Nazi toothpaste was uranium and thorium. In 1944, a German chemist in occupied Paris has been tracking down stocks of uranium and thorium, and sending it back to Germany. There was a fear that the Germans were about to develop their own nuclear weapons, so a team of spies collectively known as Alsos were tasked of discovering what the Nazi's nuclear plans were. They discovered that the material was being stockpiled by a German company, hoping to gain a post-war monopoly on radioactive toothpaste. Doramad Radioactive Toothpaste was advertised as making your teeth shine with radioactive brilliance.

- Tangent: Shazia says that Sandi at some point must have mixed up haemorrhoid cream with toothpaste, but Sandi says she has never had haemorrhoid cream. Josh had a suspected haemorrhoid, and he had to have an over-the-phone consultation with a doctor. He was embarrassed by his condition, and to make things worse at the end of the conversation the doctor said: "Um... are you the comedian Josh Widdicombe?" Similarly, some asked Sandi if she was Sandi Toksvig while she was in the middle of a colonoscopy. Sandi also tells the audience that you don't need a colonoscopy if all you have had is beetroot. Joe meanwhile went to see his GP for a haemorrhoid, and while waiting he sat next to an elderly lady who said to him: "You're that comedian aren't you. I keep thinking I see famous people around here. I thought I saw the Pope in B&Q." As they talked Joe came up with a euphemism to describe his condition, and as it was around Christmas he said: "I'm growing a little cranberry," to which the lady said: "Oh, how festive."

- XL Tangent: Sandi was in a chemist shop in New York and there was an entire isle devoted to haemorrhoid cream.

- Tangent: Other radioactive products that you could buy included the Revigator, a water jug lined with uranium ore which gave off radon gas, that claimed to, "bring back that lost element of original freshness - radioactivity." There was also the Magic Radium Massage, to be rubbed into the male sexual organs,"for firmness and strength and a pink, healthful appearance." At first, when your body is exposed to radiation it begins to fight it and you get a short-term high, but obviously the long-term effects are horrible.

- XL Tangent: Marie Curie coined the term "radioactive". Curie was Polish, but she worked in Paris because her native university in Krakow would not allow her to study because she was a woman. In 1903, she and her husband Pierre were invited to the Royal Institution in London to give a lecture on radioactivity, and she was not allowed to give it even though she was the one who made the discovery. Her papers from the 1890s are still considered too dangerous to handle, so they are all kept in a lead box and you have to wear special protective clothing to look at them. Even Curie's home recipe book is in a lead box.

- The man who is credited with inventing radio really wanted to hear the Sermon on the Mount. Guglielmo Marconi, who is the pioneer of radio although the actual invention is responsible due to the output of many people, had a theory that sound never died, it just got weaker and weaker. Thus, near the end of his life he hoped to discover the right apparatus to be able to detect all sounds ever made, and he hoped to develop the apparatus that would allow him to hear Jesus delivering this sermon. However, sound waves are gradually absorbed by air molecules till they're no longer audible.

- Tangent: Before she was a comedian, Shazia was a science teacher. She says that all her pupils did well and all graduated from Feltham Institute for Young Offenders.

- Tangent: Marconi got his first wireless patent at the age of 22, had no formal education in science, and was aided by a series of tutors and man servants. Marconi's first transatlantic message depended on a device called a coherer, which seems to be have been based on an un-patented design by a Bengali-Indian physicist called Jagadish Chandra Bose, who has been demonstrating wireless telegraphy two years before Marconi managed it. However, Bose was not allowed to work in a lab because of his race, so he made a makeshift lab at home. The first ever transatlantic transmission was from Cornwall to Newfoundland. Many people thought it was impossible due to the curvature of the Earth, but the ionosphere causes radio waves to bounce. Marconi however did not know why it worked. In 1909, he won the Nobel Prize and in his acceptance speech he freely admitted he had no idea how many of his inventions worked. In later life however, Marconi fell in with Italy's fascists. When he died in 1937, the largest wreath he got was from Hitler. Half-a-million people lined the streets for his funeral, and to commemorate his death radio stations in Italy and even the UK, USA and Canada all held a minute's silence.

- XL Tangent: Josh weighs in on the rivalry between Cornwall and Devon. The main dispute appears to over cream teas. Josh, despite being from Devon, prefers the Cornish way.

- The panel are shown a male action toy doll with no genitalia and are asked where he keeps his radio transmitter. The answer is in a fake scrotum. During the Cold War, the CIA developed a radio hidden in a fake scrotum. It was designed for pilots who might be captured and searched, and would go over your actual scrotum. However, you had to put it on one testicle at a time. Although built and tested, it was never used in the field. You can see the scrotum radio in the International Spy Museum in Washington DC, which also displays a tool kit with ten different drill bits, saws, knifes etc., that could all fit into a canister which is small enough for you to hide in your rectum.

- XL: The panel are shown a picture of eight radiators, a person and a toucan, and are asked how many radiators are being depicted. The answer is two, as radiators do not radiate heat and are thus wrongly named. Most of the heat from radiators comes from convection, when you warm up the air, which then rises, pulls cold air down, which then heats up and the cycle continues. Only a fifth of the heat from a radiator comes from radiating, which is the transfer of heat from electromagnetic waves. Humans could be described as radiators as 60% of our body heat leaves us through radiation, the heat being transferred to blood vessels at the body's surface. Toucans radiate even more than humans, using their large beaks as radiators to warm themselves up and cool themselves down. In hot weather, the bird sends blood to the beak to cool down, and in cold weather the blood vessels are constricted. Toucans can change temperature by ten degrees centigrade in just a few minutes. (Forfeit: 8)

General Ignorance

- The busiest man-made waterway in the world is the Kiel Canal in Germany. It cuts across the northern state of Schleswig-Holstein (which Sandi says part of which should belong to Denmark). In 2018 more than 42,500 ships passed through it, as well as 20,000 yachts and private motor boats. It was originally built as a way for German ships to avoid Denmark. (Forfeit: The canals of Birmingham)

- XL: If you were on the Panama Canal and heading east, the body of water you would end up in is the Pacific Ocean. Because of the way the canal curves, if you head from the Atlantic to the Pacific, you will actually end up further east than you started. You go south-east to head to the Pacific and north-west to get to the Atlantic. (Forfeit: The Caribbean; The Atlantic)

- XL Tangent: The smallest toll ever paid on the Panama Canal was 36 cents, by adventurer Richard Halliburton who swam along it.

- If you are pregnant, the best way of inducing labour is to stimulate your nipples. Several myths about inducing labour, including eating curry, walking and having sex, have all been debunked. However, according to one study, women whose nipples have been stimulated by being rolled between the fingers for between 1-3 hours a day, one at a time, are 33% more likely to go into labour within 72 hours. The same study also says it reduces the risk of heavy bleeding after delivery by 84%. (Forfeit: Voting for them; Curry)


- Josh Widdicombe: -1 point
- Shazia Mirza: -8 points
- Joe Lycett: -17 points
- Alan Davies: -25 points

Broadcast details

Thursday 23rd July 2020
30 minutes

Cast & crew

Regular cast
Sandi Toksvig Host / Presenter
Alan Davies Regular Panellist
Guest cast
Josh Widdicombe Guest
Joe Lycett Guest
Shazia Mirza Guest
Writing team
James Harkin Script Editor
Anna Ptaszynski Script Editor
Sandi Toksvig Script Editor
Andrew Hunter Murray Question Writer
Production team
Diccon Ramsay Director
John Lloyd (as John Lloyd CBE) Series Producer
Piers Fletcher Producer

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