Saturday, February 27, 2010

A Handy Resource: The Skin Deep Cosmetic Safety Database

I recently came across this handy website called the Skin Deep Cosmetic Safety Database, which was created by the Environmental Working Group. The site is useful because it allows you to search for cosmetics and personal care products by product name, ingredient, or company/brand, and it shows you their safety rating, which is based on the potential health hazards (e.g., cancer, developmental/reproductive toxicity, allergies, etc.) linked to the individual ingredients in the product. You can also browse categories of products, such as makeup, skin care, hair care, etc., and try to find safer products to use.

You'd think that with the FDA's "strict" regulation of cosmetics and personal care products, all the products that you buy should be safe. Well, before these products can be sold to the public, the U.S. Food, Drug, and Cosmetic Act (FD&C Act) requires that companies show that the products and their ingredients are safe and that they don't contain banned ingredients. But really, how do you prove that a certain chemical is "safe" before you try to market a product? A lot of these chemicals may not show any significant health effects until years down the road, and what company is willing to wait that long before marketing a product? You get the idea.

The Skin Deep Cosmetic Safety Database is neat in that it lists all the relevant information in an easy-to-use layout. The safety ratings are color coded -- green for "low hazard", yellow for "moderate hazard", and red for "high hazard" --so you can get an idea for how safe a product is at a glance. Of course, when I first discovered the site, I immediately started looking up all the products I use on a daily basis, and I was a little horrified at the results. There were a couple of things that I use that were in the high moderate to high hazard category. Yikes! As a result, I looked up some safer alternatives. You'll notice that a lot of the safest products will likely be hard to find in your average store, and that was something that annoyed me. I decided to look for products that you can find in the store with a decently safe rating instead.

HOWEVER -- this is a big HOWEVER... Just because the rating says a product is safe, it doesn't mean it actually is. What? You say. Well, it's important to look at the actual ingredient list. For example, a lot of the sunscreens that are rated the safest contain zinc oxide or titanium dioxide nanoparticles, and recent studies have shown that these particles can be absorbed through the skin. The Australian government has been looking into this and has published a review of the scientific literature on the safety of titanium dioxide or zinc oxide nanoparticles in sunscreens. A while ago, I had bought some California Baby Sunscreen thinking that it would be safer than other kids' sunscreens. Skin Deep rates it at "1" or "low hazard," but guess what. It uses titanium dioxide nanoparticles. So, is it really safer? Not sure...

Another ingredient that has been listed as hazardous is polyethylene, which I find rather puzzling. It is listed as a cancer risk (based on a study from 1955!) Huh? Polyethylene is one of the cleanest and safest plastics out there. So, for example, Maybelline's Lash Discovery mascara is dinged pretty heavily (score: 7, high hazard) partly because it contains polyethylene... Hmm. Well, my point is, look at the ingredient list carefully. Skin Deep is a useful tool, but don't take the ratings at face value.

Thursday, February 11, 2010

Blood sugar sensing tattoos for diabetics

The thought of having to draw blood (even if it's just a tiny pin prick) to check for blood sugar levels several times a day is rather unpleasant... Perhaps here is some good news for diabetics. Researchers at Draper Laboratory in Cambridge, MA have developed a tiny color-changing sensor tattoo that can detect blood sugar levels. The tattoo ink consists of nanospheres containing a fluorescent dye and a molecule that can attract and bind glucose to produce a color change. The nanospheres are injected into the outermost layer of skin. [Apparently, when blood glucose levels increase, they also increase everywhere else in the body, including the outermost layer of skin.] The nanospheres turn purple when glucose is present -- otherwise, they're yellow. Of course, there will be a range of colors depending on how much glucose is present. With a healthy blood sugar level, the tattoo is an orangish color.

The tattoo has been successfully tested in healthy mice, and the next step will be to test it in diabetic mice. The tattoo may be ready for testing in people within the next 5 years.

Pregnant women beware -- Folic acid plus vitamin B12 increase cancer risk?

A recent study of patients with heart disease in Norway found that they had an increased risk of cancer and death if they were treated with folic acid and vitamin B12. Previous studies have typically shown that folic acid deficiency can promote the development of cancer, while high doses of folic acid can enhance cancer cell growth. Apparently this particular study showed that there was an increased incidence of lung cancer among patients who received both folic acid and vitamin B12. Food in Norway isn't fortified with folic acid like it is in North America. Since 1998, folic acid has been added to flour and grain products in order to reduce the risk of neural-tube birth defects, which can result in spina bifida or anencephaly in developing fetuses. Pregnant women are also encouraged to take prenatal vitamins which contain even more folic acid and vitamin B12. What does this mean for the general population and especially pregnant women? Pending further studies, the authors recommend that the safety of widespread folic acid consumption be monitored. Wonderful...

Monday, November 16, 2009

Chemtastic Designs: New stuff...

Oops. It's been a while since I posted about Chemtastic Designs, so here are a bunch of new and updated chemistry T-shirt designs...

First, there's the "Precious" design, which features the chemical element symbols of four precious metals -- gold, silver, platinum, and palladium -- none of which are as precious as your little one. :)

There's the updated "Little Princess" design, now looking more girly:


There's the "Sweetheart Series" which features 4 different sweeteners: sucrose (table sugar), aspartame (200 times as sweet as sugar), saccharin (300x sugar), and sucralose (600x sugar). Are you a real sugar or artificial sweetener kind of person? How sweet are you? Pick your sweetheart:





There's the "chemistry is not for the weak" and "CYNIC" T-shirts:



The "HUNK" and "PUNK" and "BrAt" designs:



And finally "SAsSY" and "PrINCe charming":



That's it for now. :)

Tuesday, November 10, 2009

Cheap 'dipstick' test for pesticides in food

Researchers from McMaster University in Canada are developing a cheap "dipstick" test that can detect pesticide residues in food and drinks in less than 5 minutes. In contrast, conventional mass spectrometric testing typically takes hours to complete. The experimental paper-based test strip detects acetylcholinesterase (AChE) inhibitors, including organophosphate pesticides, and changes color depending on the amount of pesticide present. The test has pesticide detection limits on the order of 1-10 nM (bendiocarb 1 nM; carbaryl 10 nM; paraoxon 1 nM; malathion 10 nM) and should be suitable for the rapid screening of trace levels of organophosphate and carbamate pesticides.

Their work has been published in the journal Analytical Chemistry.

While the test won't be able to tell us exactly what types of pesticides are present in our food, it would be pretty neat if the test strips could eventually be available to the average consumer so that we can check the levels of pesticide residues in the stuff we buy, and make better choices about the foods we eat.

Wednesday, November 4, 2009

Tylenol reduces effectiveness of vaccines in babies?

A new study published in The Lancet, led by military and government scientists in the Czech Republic, has found that Tylenol (aka acetaminophen, paracetamol), when administered right after an immunization shot, can slightly reduce the effectiveness of vaccines in young babies (9-16 weeks old). Acetaminophen is widely recommended as an analgesic for babies, and it seems to be common practice for parents to give their babies acetaminophen right after they get their shots to prevent fever and fussiness. Fever after a vaccine is pretty common -- it's the body's immune response -- but apparently, curbing the fever also reduces the immune response and the amount of antibodies that are produced. In fact, antibody levels remained significantly lower even after the babies got their booster shots at 12-15 months old.

Doctors from the U.S. Centers For Disease Control and Prevention note that even with the use of acetaminophen, more than 90% of the babies achieved protection from the vaccines after the booster dose, but they believe that the consistency of findings from other studies suggests that routine use of fever-lowering medicines during immunization may not be recommended.

Saturday, October 17, 2009

Now there's BPA in cash register receipts?

I haven't posted about bisphenol A (BPA) at all, even though there's been A LOT of coverage on the health concerns of this chemical. First it was in polycarbonate baby bottles, then in the epoxy liners for food cans. Now we find out it's in cash receipts. What's the concern? BPA is an endocrine disruptor (estrogen mimic), and some studies suggest that human exposure to the chemical could lead to negative health effects, such as reproductive problems, obesity, and cancer. Back when I was working in industry, I used BPA quite regularly as a monomer, but of course I was handling it safely, with gloves and in a fume hood.

Apparently, the carbonless copy papers that are used for most credit card receipts and the thermal imaging papers used by most cash registers both rely on BPA chemistry. How does it work? A powdery layer of BPA combined with an invisible ink is coated onto one side of the paper so that when heat or pressure is applied, the BPA and ink molecules react to produce color. Not surprisingly, the quantities of BPA on these receipts are at the milligram level (60-100 mg) -- compare that to the nanogram amounts of BPA that can leach out of polycarbonate baby bottles. Yikes. TIP: Wash your hands well before you lick your fingers...

What's next, BPA in polycarbonate CDs and DVDs? Maybe we're better off going back to vinyl records and VHS tapes.

Monday, October 12, 2009

Detecting cancer during surgery in real time

This is cool. Researchers at Justus-Liebig University in Germany have developed a way to detect cancerous cells during surgery, by using a combination of mass spectrometry and an electroscalpel. Mass spectrometry is already used to distinguish between healthy and cancerous tissue, but samples have to be ionized before analysis by way of a high-voltage nitrogen jet -- a procedure that would most certainly not sit well with the patient...

However, the researchers found that the "surgical smoke" emitted by the electroscalpel can be collected and used as a sample for mass spectrometry. Analyzing the samples takes only a fraction of a second. By taking multiple samples within the surgical area, doctors could map out the healthy parts and unhealthy parts, which could make tumor removal more effective and reduce the number of subsequent surgeries.

The technique has already been tested in animals, and human clinical trials will begin soon. The only drawback is that a commercial mass spectrometer is very expensive (6 digits!), but the researchers believe that the cost could be reduced to about $20,000 with lower-performance mass spectrometers, which should work fine for this purpose.

Monday, October 5, 2009

The best and worst cellphones in terms of radiation output

Here's a post that caught my eye from Engadget, pointing out a list of best and worst cellphones based on the amount of radiation they put out. A quick glance at the list made me jump, as my cellphone -- the Motorola W385 -- is among the worst. Great. However, nothing in the list indicates anything about the quality or performance of the phones. My phone works extremely well in terms of sound quality and reception, and I'm not sure I would trade it in for one that emitted less radiation but had crappy reception and sound quality. And seriously, how much radiation are we talking about here?

It would take some work to dig out all the studies about the health effects of cellphone radiation that are out there, but so far, the conclusion is... inconclusive. Research is still on-going. But until then, it might be wise to not chat for hours with the cellphone next to your head. Or chat while driving -- this is a little off-topic as it has nothing to do with radiation, but it's probably more dangerous. I guarantee that if you see someone driving erratically on the road, weaving and driving much slower than the speed limit, it's not because they're intoxicated. It's because they're talking on their cellphone.

Getting back to the list of phones... If you pay closer attention to the source of this list, it's from the Environmental Working Group, an environmental advocacy group. While their website is nice in that it compiles a lot of useful information, be wary that this group tends to sensationalize science to suit their agenda. Do your research and use your common sense.

Friday, September 25, 2009

Don't drink the water at school...

According to an investigation by the Associated Press, the drinking water at public and private schools in all 50 states in the U.S. has been found to contain various contaminants, including coliform bacteria, lead, copper, arsenic, nitrates, pesticides like 1,2-dibromo-3-chloropropane (DBCP), and disinfectants. Contamination is worst at schools that use well water.

Amazingly, this problem has been mostly ignored by the federal government even as the number of violations against the Safe Drinking Water Act have increased significantly over the past 10 years. Apparently, drinking water monitoring is inefficiently spread out among too many local, state, and federal agencies, such that many risks are going unreported, and devising an effective national monitoring plan will be complicated and expensive. Right now, the EPA can only provide guidelines on environmental practices, since it doesn't have the authority to require testing for all schools.

The AP's analysis of a database of federal drinking water violations from 1998 to 2008 revealed that California (which has the most schools of any state) had the greatest number of violations (612), followed by Ohio (451), Maine (417), Connecticut (318), and Indiana (289). The most common contaminant was coliform bacteria, followed by lead, copper, arsenic, and nitrates.

I guess the good news is that the number of schools with unsafe water represents only a small percentage of the nation's 132,500 schools, but something needs to be done. Kids drink more water per pound than adults, so they are more susceptible to the effects of contaminants in water as well as food. It's probably best to give your kids (bottled, if you trust it, or filtered) water to bring to school so that they don't have to drink the school's water.

Sometimes I wonder what's in our tap water at home. We filter it, but even then, what gets through the filter? I honestly don't know, and I'm just assuming it's fine. Anyone have an atomic absorption spectrometer and GC-MS?