Weighing the pros and cons of nano ingredients

Use of nanomaterials is now widespread in the cosmetics industry - but what are the potential risks? We asked Jaydee Hanson, policy director for the International Center for Technology Assessment and an expert on nanotechnology.

How do you define nanomaterials? 

First, it is important to talk about “engineered” nanomaterials - that is, nanomaterials that have been engineered to have useful properties at the nanoscale. These properties occur at the nanoscale and may not appear at the larger scale.

The US Food and Drug Administration asks persons developing products using nanomaterials to report any engineered nanomaterials in the product that are smaller than 1,000nm. We would say that we are most concerned with nanomaterials that in any dimension are smaller than 500nm. Studies have shown that nanomaterials smaller than 250nm can cross the placental barrier between a mother and her offspring, so we think that a general threshold of 500nm will catch most of the products that are likely to enter the body.

Use of nanomaterials in anti-aging, sunscreens and nail products is well known. What other areas of the cosmetics industry is their use expanding into? 

Virtually every part of the cosmetics industry is using, or planning to use nano ingredients.

Remind us why their use is now widespread - what are the cited benefits?

Nanotechnologies allow enhanced properties in many areas of interest to the cosmetics industry, including UV protection, deeper skin penetration, and improved hydration. Nanotechnology also allows the “packaging” of many ingredients in semi-soluble packets that breakdown as the product is being applied, not before.

What evidence have you found that nanoparticles in cosmetic products are a potential risk to people’s health and the environment? 

Of the various kinds of nano-materials used in cosmetics, it appears that the metallic nanomaterials like titanium dioxide, nano copper, and nanosilver may raise health concerns along with any use of carbon nanotubes or buckeyballs.

Nanotitanium dioxide used in cosmetics can be absorbed through the skin if the skin is broken, hairy, or if the nanoparticles are coated with other nano materials like silica. Inhalation of sprayed cosmetics and sunscreen is another avenue for exposure. Finally, lipsticks, glosses etc. can be swallowed by adults and infants, and children frequently lick off lotions that might contain nanomaterials.

How would you like to see the use of nano materials in the cosmetics industry developing in the future? 

I would like to see the cosmetics industry develop strategies to keep nanomaterials that are of a size that can enter the human cells (roughly 250nm) out of products. This is especially important for the cosmetics used by the most vulnerable populations: children, pregnant women, and adults with skin damage, lung disease or gastrointestinal disease. I would like to see the cosmetic industry address the data gaps in the toxicity of nano metallic oxides and publish their research in free journals.

Jaydee Hanson will be presenting at the Sustainable Cosmetics Summit in New York City, May 14 - 16.