Urine is commonly believed to be sterile until it reaches the urethra but that has led to numerous misconceptions about what can and should or should not be done with it. Drinking urine is a bad idea, for example, because even though it is sterile it contains urea and other substances that can still be toxic.

A new study finds that in scenarios of increasing global temperatures, methane-generating microbes, found in thawing lake sediments may ramp up production.

Though methane stays in the atmosphere for far less time than CO2, it is 25X more potent during that period. Concerns about methane have risen because of concerns about possible leaks due to increased natural gas, which produces far less CO2 than coal, and that methane may be released as climate changes.

A new study has identified a familial association in spontaneous coronary artery dissection, a type of heart attack that most commonly affects younger women, suggesting a genetic predisposition to the condition, researchers say.

A diagnosis of thyroid cancer can be devastating to professional singers, because surgical removal of the thyroid commonly causes voice changes. Massachusetts Eye and Ear surgeons developed a neural monitoring system to be used intraoperatively to improve outcomes. In the first study of its kind, they confirmed the hypothesis that the careers of singers and professional voice users are not impaired after thyroid surgery using this device.

The sale of human breast milk on the internet poses serious risks to infant health and needs urgent regulation, according to a new editorial in BMJ.

The nutritional benefits of breast milk for babies are widely documented, but many new mothers find it difficult or are unable to breastfeed. In addition to social pressure, this pushes some mothers to purchase human breast milk on the internet - a market that has been growing rapidly. Despite appearing as healthy and beneficial products, many new mothers and even some healthcare workers are not aware that this market is "dangerous" and "putting infant health at risk" because it is not regulated, argues Sarah Steele, a lecturer at the Global Health, Policy and Innovation Unit at Queen Mary University London, and colleagues.

There are significant differences in personalities between regions in Britain - Scots are amongst the friendliest and most co-operative residents, Londoners the most open and Welsh people are the least emotionally stable, according to analysis of surveys of just under 400,000 people from England, Wales or Scotland (Northern Ireland was excluded as sample sizes were too small), around two-thirds of whom were female.

The study is based on data that was gathered as part of the Big Personality Test, an online survey published by the BBC in 2009 as part of a collaboration between the BBC and the scientific community, BBC Lab UK.