/oss/taxonomy/term/765/all en /oss/article/history-general-science/iron-fallout-hair-permanents <p>For most people a car is just a vehicle that gets them from one place to another, and as far as cleanliness is concerned, occasionally driving through a car wash is good enough. But some individuals are so reviled by a speck of dirt that they will wash, wax and polish until the car has the appearance of one sitting in a dealer’s showroom. The wheels, be they steel or alloys of magnesium or aluminum, receive much attention because they must shine! And this is where focus falls on iron fallout.</p> Tue, 18 Jun 2024 00:21:49 +0000 Joe Schwarcz PhD 9980 at /oss /oss/article/technology-history/wrap-your-hair-around-biotechnology <p>What comes to mind when you think of biotechnology? Maybe it’s Dolly the cloned sheep, or GMOs, or stem cell therapy, or DNA profiling, or mRNA vaccines. Rightly so. These are indeed examples of biotechnology, defined as the “manipulation of living organisms, or of substances produced by living organisms, with an aim towards developing useful agricultural, industrial or medical products.” But how about a lotion formulated to repair damaged hair? Probably not something you would connect to biotechnology. Just wait and see. First, though, a quick lesson on the chemistry of hair. </p> Thu, 06 Jul 2023 13:19:29 +0000 Joe Schwarcz PhD 9560 at /oss /oss/article/did-you-know-general-science/pangolins-use-rocks-lieu-teeth <p><span>Pangolins, or scaly anteaters, are amazing little mammals. There are eight species of them, and they are the only living creatures in their order of Pholidota. Spread throughout Asia and Africa, they can be as small as 2 kg or as large at 35 kg. But if you meet one, you will probably be struck by their scales. </span></p> Thu, 31 May 2018 18:20:00 +0000 Ada McVean B.Sc. 7120 at /oss /oss/article/health-you-asked/what-brazilian-hair-straightening-treatment <p style="text-align:justify"><a href="http://blogs.mcgill.ca/oss/?attachment_id=3379" rel="attachment wp-att-3379"><img alt="keratin" height="150" src="http://blogs.mcgill.ca/oss/files/2012/11/brazilian-150x150.jpg" width="150" /></a>In “Brazilian straightening” a protein known as keratin is mixed with formaldehyde and is applied to hair followed by heat treatment. Results can be surprisingly good with the straightening effect lasting for weeks. The problem is that the key substance in the treatment is formaldehyde, a compound with a cloud hanging over its head. Formaldehyde can not only cause allergic reactions, it is a possible carcinogen, especially when inhaled. The heat treatment volatilizes formaldehyde so inhalation is indeed possible. At concentrations above 0.1 ppm in the air formaldehyde can cause irritation of the eyes and throat and can trigger asthma in susceptible people. Such levels may be reached during a keratin treatment which is why hair dressers have taken to wearing masks when applying formaldehyde. Of course, the extent of exposure is critical and having such a treatment once in a while is not likely to be harmful, but working constantly with formaldehyde may present a risk. Supposedly these hair treatments contain only 0.2% formaldehyde, which is deemed to be safe, but the content of these products is not regulated in any way. <a href="http://blogs.mcgill.ca/oss/2012/11/18/what-is-a-“brazilian”-hair-straightening-treatment/">Read more</a></p> Mon, 19 Nov 2012 00:33:02 +0000 Joe Schwarcz PhD 1810 at /oss