NANO-SAFETY [08 October 2007]
A White Paper on NANO-SAFETY
Nanotechnology has captured the imagination of writers, entrepreneurs, venture capitalists, and even politi- cians. Nanotechnology is postulated as the solution to many of the world’s problems, ranging from energy sto- rage to curing cancer. At the same time that many applications have been developed, and many more are being envisioned, a new concern has arisen: the issue of nanotechnology safety. Articles have been written about the need for investigation on the impact on safety. Numerous reports of anticipated dangers from nanotechnology- based products have been published (the July 2007 issue of Consumer Reports is only one example). Other spe- cific concerns, such as those below, have been appearing in various media.
Silver particles are instrumental in expediting the healing of wounds. A study done by the Italians in 2006 indicates that 12nm silver particles will cure infections as well. Employing the 12nm silver particles prevents the bacteria from developing a resistance to the treatment, unlike what happens with drug- based approaches. Nevertheless, the Environmental Protection Agency has put a restriction on any ap- plication of silver nano particles because of the perceived potential of its also destroying good bacteria if released into the environment.
DuPont published a report in 2004 that concluded that carbon black nanoparticles are unhealthy and can cause damage in a person’s lungs. While containing factual information, the article is misleading people to think that only carbon black nanoparticles are dangerous. People who work in coal mines have been aware of the dangers of coal dust, regardless of size quantification, for over 100 years. [Fact: There is research that has shown particles under 10m have the ability to be absorbed by passing through human tissue. The application of the “nano” characterization is misleading at best, and quite possibly disingenuous.]
3) The city of Berkeley, California, has passed an ordinance that requires Material Safety Data Sheets (MSDS) on any Nanomaterials that will be brought into or manufactured in the city. Unfortunately, data sheets that would cover all aspects of the materials do not exist, and actually can not exist, because there is no overall understanding of the properties that need to be evaluated. Existing MSDS are based on the physical properties that can be readily measured, the bulk material properties. These properties, which include the melting and boiling points irrespective of size, are known and the values are pub- lished. This is not the situation in nanomaterials since the material properties change as the size be- comes smaller. The ability to quantify the properties at the nanoscale needs additional development. Without the tools to quantify properties, the development of specifications is misleading.
Expressing these and other concerns without a means of evaluating the issues and identifying where the actual concerns should be does not promote good science. What is missing is a comprehensive effort that addresses the issues, identifies the problems, and works toward solutions. The crucial question is what needs to be done, and how quickly can the issues be addressed and resolved. Unfortunately, nanotechnology ushers in a new realm of science that retains almost none of the existing knowledge of bulk material properties. The old, estab- lished “truths” no longer can be relied on in the nano realm as fundamental properties of materials. For exam-
Copyright 2007, Walt Trybula & Texas State University
Page 2 of 7