/oss/taxonomy/term/211/all en /oss/article/student-contributors-did-you-know-general-science/salon-free-highlights-are-just-spray-away <p>Summer is almost here! Tans will get darker and hair will get lighter. If you <i>really</i> want to get blonder this year, many brands sell hair lightening sprays – a way to heighten the sun’s natural hair brightening process.</p> <p>The key factor for the sun’s effect on hair is ultraviolet light. These energetic rays break bonds between the atoms of melanin, the compound responsible for hair pigmentation. As the melanin breaks down into colourless compounds, hair is lightened.</p> Thu, 19 May 2022 20:03:36 +0000 Haleh Cohn 9116 at /oss /oss/article/covid-19-health-pseudoscience/upside-down-doctor <p>Dr. Joe Mercola, an osteopathic physician who has made an impressive fortune selling supplements through his online store, has a new book out about the COVID-19 pandemic, a book which he co-authored with Ronnie Cummins, an organic food crusader. This book, as well as Mercola’s decades of peddling health misinformation on the Internet, exemplifies the dangerous blind spot of the wellness movement.</p> Fri, 04 Jun 2021 20:40:54 +0000 Jonathan Jarry M.Sc. 8757 at /oss /oss/article/environment-history-science-science-everywhere/solution-skunk-pollution <p style="text-align:justify"><a href="http://blogs.mcgill.ca/oss/?p=5427"><img alt="skunks" height="192" src="http://blogs.mcgill.ca/oss/files/2013/06/skunks-300x192.jpg" width="300" /></a>I remember the first time I ever smelled the fragrance of a skunk.  I thought someone had let off a stink bomb.  You see, even back then I was a lot more familiar with emissions from test tubes than from animals.  This certainly smelled as if someone had mixed sodium sulfide with an acid to release hydrogen sulfide-the classic smell of rotten eggs and stink bombs.  A smell potent enough to quickly drive any living creature away.  Which of course is exactly what the skunk has in mind when it lets loose from the little scent glands on either side of its rectum.</p> <p style="text-align:justify">Scientists have long been intrigued by the chemical composition of skunk aroma.  Way back in 1862, the famous German chemist Friedrich Wohler received a gift of "Nordamerikanischen Stinkthiers" fluid from a "freunde in Neuyork."  It was too smelly for the great man to work with so he gave it to one of his underlings, identified only as Dr. Swarts of Gent.</p> <p><a href="http://blogs.mcgill.ca/oss/2013/06/12/a-solution-to-skunk-pollution/">Read more</a></p> Wed, 12 Jun 2013 14:14:42 +0000 Joe Schwarcz PhD 1958 at /oss /oss/article/health-you-asked/how-does-peroxide-whiten-teeth <p>Ancient Romans, for example, used urine and goat milk to whiten their teeth. This concoction is not as far-fetched as it might first appear. Urine, contains ammonia which is a cleaning agent found in many household products. But today there’s no need to rinse the mouth with urine, which incidentally is usually sterile. Chemistry has given us more effective products.</p> Mon, 21 Jan 2013 02:00:49 +0000 Joe Schwarcz PhD 1862 at /oss /oss/article/general-science-you-asked/hydrogen-peroxide-bodys-best-defence-system <p>Enzymes are special protein molecules that speed up chemical reactions. But why should liver contain an enzyme that helps degrade hydrogen peroxide? Because hydrogen peroxide actually forms as a product of metabolism and can do some nasty things. It can break apart to yield hydroxyl radicals that attack important biochemicals like proteins and DNA. To protect itself, the body makes catalase, the enzyme that decomposes hydrogen peroxide before it can form hydroxyl radicals.</p> Wed, 18 Jan 2017 18:47:42 +0000 Joe Schwarcz PhD 1383 at /oss