There is a SCIENTIFIC REASON for putting the lid down (end of discussion...get with the program everyone!!!):
http://www.abc.net.au/science/k2/moments/s1143577.htm
Flushing Out The Truth
Listen to Karl talk about Flushing Out The Truth
(You will need Real Audio which you can download for free)
Sometimes, if things are a bit rushed at work, we might grab a quick sandwich at our office desk. But you'd never be in such a hurry, as to even dream of eating off the toilet seat, because we all "know" that toilets are really "dirty", and loaded with germs. But on average, per square centimetre, your desk has 50 times more bacteria than your toilet seat!
This was discovered by Dr. Charles Gerba, a microbiologist from the University of Arizona. He's Dr. Germs. Over the last three decades, he's written some 400 papers in peer-reviewed journals on infection and disinfection.
He solved the problems that the National Science Foundation was having with the waste-water treatment system in the Antarctic at McMurdo Station. He helped out with advice on water-recycling systems for both NASA and the Russian MIR Space Station. He loves his work so much, that he even gave his first son the middle name of Escherichia, which is the "E" in E. coli, that famous faecal bacterium. He got around family resistance by telling his father-in-law that Escherichia was the name of a king in the Old Testament of the Bible.
Dr. Gerba has also studied germ counts in the house, and by doing so, discovered the right way to flush the toilet. You should flush with the lid down.
If you flush with the lid up, a polluted plume of bacteria and water vapour erupts out of the flushing toilet bowl. The polluted water particles float for a few hours around your bathroom before they all land. Some of them will land on your tooth brush.
Dr Gerba also found that in the home, the kitchen sponge had the highest germ count, followed by the kitchen sink. The lowest bacteria count, out of 15 household locations, was the toilet seat. He said (perhaps a little jokingly), "If an alien came from space and studied the bacterial counts, he probably would conclude he should wash his hands in your toilet". He went on to say what they might do in your sink.
So if you flush with the lid up, you are probably brushing your teeth with toilet water. I guess that's one story to tell the males in your household, so that they put the lid down, because if the put the lid down, they have to put the seat down as well.
In mid-2001, he and his team looked for five different types of bacteria (E. coli, Klebsiella pneumonia, Streptococcus, Salmonella and Staphyloccus aureus). They studied offices at four locations - New York City, San Francisco, Tampa in Florida, and Tucson, Arizona. At each site, they tested surfaces three times a day for 5 days. They sampled 12 different surfaces - desktop, phone, computer mouse, computer keyboard, microwave door handle, elevator button, photocopier start button, photocopier surface, toilet seat, fax machine, refrigerator handle and the water fountain handle. The team wanted to see the effect of cleaning the surface. So at each location, one group of employees used disinfecting wipes to clean the surfaces they worked with, while the other group did not. (The study was partly funded by a company which makes disinfecting wipes.)
The results were astonishing. In terms of bacteria per square inch, they found that the phone receiver was the filthiest - 25,000 (probably because many people can share the same phone). This was followed by the desktop at 21,000, the computer keyboard at 3,300 and the computer mouse at 1,700. The least contaminated surface was the toilet seat with only 49 bacteria per square inch - making it about 50 times cleaner than the desktop. Gerba says that, for bacteria, the "desk is really the laptop of luxury. They can feast all day from breakfast to lunch and even dinner."
Pat Rusin from the University of Arizona is not sure why the shared toilet seat, which you would expect to be a maelstrom of maximum microbial activity, is actually one of the cleanest. He said "What we found, and what we are still theorising as to why, is that the toilet seat was always the cleanest site." One theory is that the toilet seats are too dry to give a good home to a large population of bacteria.
The other major finding was that if you went to the trouble of using their sponsor's anti-bacterial wipes, you could drop the bacteria count by about 99.9%.
So while I intellectually know that the toilet seat has a lower bacterial count than the desktop, I'm not going to have my next snack in the toilet. Maybe I'll go half-way and wipe down my desktop, not with a germ-laden sponge containing 10,000 bacteria per square inch, but with clean toilet paper that I can throw away.
Swalker (always puts the lid down!!!)