September 23rd, 2013 by Dr. Val Jones in Health Tips
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This actress keeps her dermatologist on speed dial too.
As a light skinned, be-freckled woman with a history of pre-melanoma, I have been sternly instructed to keep my dermatologist on speed dial. Every six months I dutifully return to his office for inspection – nervously eyeing the biopsy tray as I sweat through my paper gown, legs dangling from a vinyl exam table.
In preparation for my most recent trip, I decided to be “an empowered patient” and arrive with a list of general dermatology and skin care questions that could be answered during my skin check. Judging from the near-syncopal episodes that I induced in my dermatologist while describing some of my hygiene practices, I’m not being very good to my skin. In fact, he wanted me to know that at least three products that I currently use are “of the devil.” Just in case you are inadvertently engaging in demonic skin care practices as I was – I thought I’d share what I learned:
1. Dryer sheets. According to my dermatologist, dryer sheets contain “a horrible chemical that no one can pronounce” that becomes “slathered all over your clothing” during the drying process. Although I was fond of the fresh scent and soft texture of my gym clothes, he assured me that heat and moisture was the best way to re-activate the irritating chemicals on delicate skin, virtually guaranteeing a contact dermatitis of the nether regions. So if you’ve been experiencing any unpleasant post-work out skin “issues” – consider dryer sheets as a potential cause.
2. Antibacterial ointments. Personally, I find that over-the-counter antibacterial ointments do a great job of preventing razor bumps. However, my dermatologist says that repeated or excessive use of these products can lead to allergies and colonization with antibiotic-resistant organisms. So… unless you want to be giving MRSA a “come-hither stare,” you might want to opt out of the Neosporin.
3. Battery-operated exfoliating brushes. I’ve seen so many ads for Clarisonic-type products that I figured they would be a reasonable choice for facial exfoliation needs. In fact, this topic may be somewhat controversial since I know other doctors who recommend these products. However, my dermatologist says that they are overkill and might do more harm than good to delicate facial skin, especially if you use any products that have an exfoliating acid included in their ingredient list, or if you use scrub creams. In other words, if you wash your face regularly, you probably don’t need to use additional aggressive cleaning measures.
In addition to the information provided about evil products commonly used by innocent people across America, my dermatologist offered these general tips for healthy skin:
1. You don’t need so much moisturizer. “You don’t need to put on moisturizer every night just because your mother told you to,” he said, bow tie looming large at eye-level. “Women think they need to apply moisturizer multiple times a day, but there is enough moisturizer in sunscreens and anti-oxidant serums to make additional products unnecessary.”
2. Throw away your 10x mirror. “Honestly, no one sees your skin at 10x, so why should you worry about what it looks like so close up? The best way to make your pores look smaller is to quit looking at them under a magnifier.”
3. Use physical block sunscreen every day. Most of the cheaper, spray-on sunscreens use chemicals to scatter light, but zinc-based sunscreens physically block incoming UV radiation. “The most important part of an ‘anti-aging’ regimen is to avoid sun exposure, and the best way to do that is with constant use of physical blocks.”
4. Skin-lightening cream (hydroquinone) can reduce the appearance of sun damage. Hydroquinone is the active ingredient in most skin-lightening creams. It acts to down-regulate melanin production in melanocytes, but can be reversed fairly easily by UV exposure (i.e. sunlight up-regulates melanin production). So even if you’re already pale-skinned, hydroquinone products can even out skin tones and sun spots – but only if you simultaneously commit to aggressive avoidance of UV exposure.
I hope you’ve found these skin tips enlightening (pun intended). I’ll have to think of some other good questions to ask my dermatologist in 6 months from now, during my next cancer screening. Because as an empowered patient, I intend to learn as much as I can in my 15 minutes with the doctor, and then share it with as many people as possible. 🙂
October 22nd, 2012 by admin in Health Tips
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Some of you may find this surprising, but I don’t mind ironing.  Unlike giving a lecture, writing a column or appearing on TV or radio, you get immediate gratification.  You see the results of your efforts.  Wrinkles that were there before are gone.  I suspect, however, that not everyone shares my enthusiasm for this task.  The textile industry realizes this as well and has responded by producing a variety of “durable press” fabrics that can withstand wrinkles.  But withstanding allegations of toxicity is more of a challenge.  In this case the hullabaloo is about formaldehyde, the chemical used to fashion garments that can come straight out of the washing machine and sidestep the ironing board.
Wrinkling is a direct consequence of the molecular structure of cellulose, the main component of cotton.  This polymer is made up of repeating units of glucose, but the important feature of cellulose, as far as wrinkling is concerned, is that adjacent molecules can form weak associations with each other.  These “hydrogen bonds” are responsible for maintaining the shape of the fabric.  But when cotton is moistened, water molecules insert themselves between the long chains of cellulose, cleaving the hydrogen bonds.  The cellulose molecules can now move relative to each other, and as the fabric dries and the water molecules evaporate, the hydrogen bonds reform holding the fabric in its new shape, which is usually wrinkled.  Another factor in wrinkling is the thickness of the cotton fibers.  Fabric woven with very fine cotton thread will crease less than fabric made with more coarse thread.
Heat can also disrupt hydrogen bonds, which explains how ironing works. Â The weight of the iron flattens the fabric and the novel shape is then retained as the material cools. Â Ironing with steam is especially effective because the added water molecules serve as an internal lubricant, breaking hydrogen bonds and allowing cellulose molecules to slide past each other. Â As heat is applied, the water evaporates, hydrogen bonds reform, and we have a smoothened fabric. Â At least until it gets moist from perspiration.
The earliest attempts to reduce wrinkling made use of starch, possibly as early as 800 BC. Â Like cellulose, starch is made of repeating units of glucose, and the two substances have an affinity for each other. Â A starch solution readily penetrates into cotton fibers and when the fabric dries the molecules of starch bind to each other forming a hard network, stiffening the fiber. Â An analogy would be a canvas water hose that can be easily folded when empty, but becomes stiff when filled with water. Â The problem with starch, though, is that it comes out in the wash and has to be applied each time.
The early part of the twentieth century saw the introduction of a number of synthetic resins such as urea-formaldehyde which presented textile manufacturers with an opportunity to “stuff” fibers with a substance that would not wash out as readily as starch.  It worked reasonably well, but when the chemical structure of cellulose became clarified in the late twenties, chemists came up with another idea.  Given that wrinkling is caused by the movement of the cellulose molecules relative to each other, why not find a way to form bonds between cellulose molecules that are not as easily disrupted by moisture as hydrogen bonds?
Formaldehyde was just the molecule for this task.  It readily reacts with the hydroxyl groups on cellulose to form cross-links, much like the rungs of a ladder.  The idea is to form the fabric into the desired shape and then treat it with formaldehyde to retain that shape.  Manchester textile manufacturer Tootal Broadhurst Lee was the first company to use this process commercially back in the 1930s, producing the world’s first “wrinkle-free” garment, the “Tootal” tie.  But it wasn’t long before a wrinkle appeared in the novel technology.  The garments released the irritating odour of formaldehyde.  Not only was this smell unpleasant, but formaldehyde was also responsible for the allergic contact dermatitis reactions that emerged with the use of the durable press fabrics.  Later there would be increased concern about formaldehyde treatments as studies began to show that at least in animals the chemical was a carcinogen.
By the 1990s significant improvement had been made in technology to reduce formaldehyde release from treated fabrics.  During manufacture the fabric was subjected to huge rollers that squeezed out excess formaldehyde followed by heat treatment in an oven to cure the formaldehyde and prevent it from being released.  Another method that requires less formaldehyde, known as “vapour phase technology,” involves hanging moistened clothing in an airtight chamber and treating it with a gaseous mixture of formaldehyde and sulphur dioxide to form the required cross-links.
A number of other cross-linking agents have also been introduced, with the most widely used ones being dimethyloldihydroxyethyleneurea (DMDHEU) and ethylene-urea/melamine-formaldehyde (EUMF). Â While effective at producing wrinkle-free fabrics, they, like formaldehyde, can still cause allergic reactions. Â Exposure to permanent-press fabrics should always be considered as a possible cause of dermatitis that has no obvious trigger.
Although the amount of formaldehyde released from permanent press fabrics is unlikely to affect health except for rare cases of allergic dermatitis, manufacturers have made determined efforts to reduce formaldehyde exposure.  The textile industry uses a “Sealed Jar Test” to measure the amount of formaldehyde released from one gram of fabric under controlled conditions.  Since the early days of durable press, the amount released has been decreased by a factor of ten.  Cross-linking agents that do not release formaldehyde at all, such as dimethylurea glyoxal (DMUG), have also been developed but they cost more and do not perform quite as well.
The advent in the 1960s of polyester fabrics with a greatly reduced tendency to wrinkle took some of the pressure off producing wrinkle-resistant cotton fabrics.  But since not everyone likes the feel of polyester, even when blended with cotton, the prospect of producing a truly permanent-press cotton fabric still looms in front of manufacturers’ eyes.  They’re getting there though.  Recently I bought some shirts that barely need the touch of an iron.  And as far as formaldehyde exposure from such fabrics goes, well, I think there are far bigger wrinkles in the fabric of life to worry about.
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Joe Schwarcz, Ph.D., is the Director of McGill University’s Office for Science and Society and teaches a variety of courses in McGill’s Chemistry Department and in the Faculty of Medicine with emphasis on health issues, including aspects of “Alternative Medicine”. He is well known for his informative and entertaining public lectures on topics ranging from the chemistry of love to the science of aging. Using stage magic to make scientific points is one of his specialties.
