There have been many toilet-related injuries and deaths throughout history and in urban legends. Accidental injuries Infants and toddlers have fallen into toilet bowls and drowned. Safety devices exist to help prevent such accidents. Injuries to adults include bruised buttocks, tail bones, and dislocated hips from unexpectedly sitting on the toilet bowl rim because the seat is up or loose. Injuries can also be caused by pinching due to splits in plastic seats or by splinters from wooden seats, or if the toilet itself collapses under the weight of the user. Older high tank cast iron cisterns have been known to detach from the wall when the chain is pulled to flush, causing injuries to the user. The 2000 Ig Nobel Prize in Public Health was awarded to three physicians from the Glasgow Western Infirmary for a 1993 case report on wounds sustained to the buttocks due to collapsing toilets. Furthermore, injuries are frequently sustained by people who stand on toilets to reach a height, then slip and fall. There are also instances of people slipping on a wet bathroom floor or from a bath and concussing themselves on the fixture. Toilet related injuries are also surprisingly common, with some estimates ranging up to 40,000 injuries in the US every year. In the past, this number would have been much higher, due to the material from which toilet paper was made. This was shown in a 1935 Northern Tissue advertisement which depicted splinter-free toilet paper. In 2012, 2.3 million toilets in the United States, and about 9,400 in Canada, were recalled due to faulty pressure-assist flush mechanisms which put users at risk of the fixture exploding. Injuries caused by animals There are also injuries caused by animals. Some black widow spiders like to spin their web below the toilet seat because insects abound in and around it. Therefore, several people have been bitten while using a toilet, particularly outhouse toilets. Although there is immediate pain at the bite site, these bites are rarely fatal. The danger of spiders living beneath toilet seats is the subject of Slim Newton's comic 1972 country song The Redback on the Toilet Seat. It has been reported that in some cases rats crawl up through toilet sewer pipes and emerge in the toilet bowl, so that toilet users may be at risk of having a rat crawl up their buttocks. Many rat exterminators do not