EDF Health

Nano On A Hot Tin Roof

By Cal Baier-Anderson / Published: July 22, 2008

Cal Baier-Anderson, Ph.D., is a Health Scientist.

Andrew Maynard, of the Project on Emerging Nanotechnologies, recently blogged about an Australian study that documented an odd effect of sunscreens containing nanoscale titanium dioxide (TiO2).  The study was prompted by the observation that installers of metal roofs who used these sunscreens inadvertently transferred the product onto the roofs. In places where the workers’ skin had touched the painted metal surfaces, the paint showed accelerated weathering. Why?  Because the particular type of nanoscale TiO2 in the sunscreen (the anatase crystal form) is photoactive – when it absorbs UV light, it releases free radicals that speed up the oxidation of the underlying paint.

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Burning Questions: Are Sunscreens Containing Nanomaterials Safe?

By Cal Baier-Anderson / Published: July 16, 2008

Cal Baier-Anderson, Ph.D., is a Health Scientist.

Ah, summer!  It’s a great time to be outdoors, enjoying the warm, sunny weather.  Before you go outside, be sure to grab your sunscreen, that essential product that protects against skin cancer and sun damage.  But which kind of sunscreen is best?  There is a mesmerizing array of sunscreen options, but for our purposes let’s limit the question to one:  Nano or not nano?

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Nano Down the Drain

By Cal Baier-Anderson / Published: June 9, 2008

Cal Baier-Anderson, Ph.D., is a Health Scientist.

The proliferation of nanoscale materials in consumer products is impressive:  nano titanium dioxide and zinc oxide in sunscreen, buckyballs in face creams, and nanosilver in socks are but a few examples of what is currently available for purchase.  But they make me wonder:  what happens when the nanomaterials in or released from these products are washed down the drain?   Read More »

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Bacterial Resistance to Silver (Nano or Otherwise)

By Cal Baier-Anderson / Published: April 29, 2008

Cal Baier-Anderson, Ph.D., is a Health Scientist.

A recent article posted on scienceline includes a claim that bacteria cannot develop resistance to silver, which is widely used as an antimicrobial.  That assertion is not only false, but also dangerous. Read More »

Posted in Emerging science, Health science, Nanotechnology / Tagged , | Read 4 Responses

My CNT is Better than Your CNT… Or At Least It’s Different

By Cal Baier-Anderson / Published: April 7, 2008

Cal Baier-Anderson, Ph.D., is a Health Scientist.

After posting to this blog the other day, I came across a brand new study characterizing the heterogeneity of carbon nanotubes.  The authors of this study looked at 11 single-wall carbon nanotubes (SWCNTs) from 10 different suppliers and found that SWCNT composition varies dramatically depending on synthesis method, feedstock, purification steps, and other factors.  Read More »

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Getting to General Principles: Are We Making Progress?

By Cal Baier-Anderson / Published: April 2, 2008

Cal Baier-Anderson, Ph.D., is a Health Scientist.

With conventional chemicals, experience has allowed us to articulate general criteria based on chemical properties that identify chemicals of greatest concern.  For example, persistent and bioaccumulative chemicals are assigned a high priority, whereas chemicals that quickly degrade and don’t build up in blood or tissue are, as a rule, likely to be of lower priority.

Concerns about nanomaterials arise from observations that properties that emerge or are greatly enhanced at the nanoscale can alter behavior, including biological activity.  These properties make such materials different from conventional forms of the same chemicals.  But can a general principle that nanomaterials pose a greater concern than their conventional counterparts be supported?  Read More »

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