I just came across a little blurb in this week’s issue of Science, noting that the EPA has finally made some decisions about regulating nanomaterials. A quick read indicates that 1) the EPA has decided that for chemicals already registered under their TSCA Chemical Substance Inventory (TSCA is the law enacted to protect us humans and the environment from nasty chemicals – and the inventory is a listing of all those chemicals from which we’re being protected) – nano-formulations of those chemicals will not require new registration (or registration as a new chemical) and 2) they are asking for voluntary submission of health and toxicity data, by manufacturers and users of nanomatierals. Huh.
So what does this mean? I was confused when I first read it. After reading and writing about nanomaterials, I thought one of the advantages of producing these things were specifically (in some cases) because they act differently than their bigger, larger, brothers and sisters. For example compounds like titanium dioxide and zinc oxide were nanoized in the first place was to take advantage of the differences between the larger forms and the smaller. So, I though, maybe the EPA didn’t really mean that.
Fortunately, EPA has an easily readable paper that explains these things – like how they define a new chemical - in great detail. According to their TSCA Inventory Status of Nanoscale Substances – General Approach (2008) paper, EPA focuses on “molecular identity.” In this case, chemicals that have the same molecular formulas, the same crystal structures, the same spatial arrangement of atoms – are the same chemical. That means, according to the EPA, and to borrow from Dr. Suess, titanium dioxide is titatinium dioxide no matter how small.
Why is it important to distinguish a chemical as “new?”
Normally, when a company manufactures a “new chemical,” unless it’s exempt – the company must submit a Pre-manufacture Notice, which then triggers some basic testing. That little bit about “exempt” can be important. In fact, you’ve likely got some of those “exempt” chemicals floating around in you right now. Remember all the hubbub about PFOA and PFOS? Those chemicals in Gore-Tex and Teflon and other products? Well perfluorinated chemicals involved in the production of PFOA and PFOS were granted exemptions, in this case because they were in commerce before TSCA came along. But look what happened. Now we’ve got those chemicals contaminating wildlife around the world. To be fair, it’s possible that would have happened anyway – who knows. But here’s the catch, the exemption was granted with the understanding that under TSCA, should any manufacturer realize that there might be health and safety issues, such information “ [would] be submitted to the Agency…when companies learn of it.” In the case of these products this didn’t happen, and Dupont ended up settling that account for $10 million dollars.
There are various ways a chemical might be exempt. If it’s used only for research and development, it might be exempt. If it’s produced in low volume, it might be exempt. And, if there’s some indication that it would be released in only small concentrations or that there would only be small exposures, it might be exempt.
Bottom line? There will be nanomaterials that will not be required to undergo testing.
Ah but rest assured, EPA has considered that some of these exempt or untested chemicals may have adverse health or environmental effects. You see, they recently announced their Nanoscale Materials Stewardship Program, where according to the program description, “Participants are invited to voluntarily report available information on the engineered nanoscale materials they manufacture, import, process or use,” should they happen to observe anything funky happening with their materials.
Let’s hope they do.
For a good readable explanation of TSCA and how it may or may not apply to nanomaterials check out the article “TSCA and Engineered Nanoscale Subtances,” by Lynn L. Bergeson and Ira Dassa and published in Sustainable Development Law and Policy.