This article originally appeared on the National Nanomanufacturing Network's InterNano website earlier today. It is licensed under Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported.
In late December 2009, California’s Department of Toxic Substances Control (DTSC) received the first response1 to its January 22, 2009 information request regarding carbon nanotubes2. The original request targeted 26 purported California manufacturers and/or importers of carbon nanotubes3.
It asked for information regarding analytical test methods, environmental fate and transport, and other relevant environmental, health, and safety information. The request was issued by DTSC under authority granted by California's Health and Safety Code 699, Sections 57018-57020. Stanford University was the first entity to respond to the six specific questions contained in DTSC’s request:
1. What is the value chain for your company? For example, in what products are your carbon nanotubes used by others? In what quantities? Who are your major customers?
2. What sampling, detection and measurement methods are you using to monitor (detect and measure) the presence of your chemical in the workplace and the environment? Provide a full description of all required sampling, detection, measurement and verification methodologies. Provide full QA/QC protocol.
3. What is your knowledge about the current and projected presence of your chemical in the environment that results from manufacturing, distribution, use, and end-of-life disposal?
4. What is your knowledge about the safety of your chemical in terms of occupational safety, public health and the environment?
5. What methods are you using to protect workers in the research, development and manufacturing environment
6. When released, does your material constitute a hazardous waste under California Health & Safety Code provisions? Are discarded off-spec materials a hazardous waste? Once discarded are the carbon nanotubes you produce a hazardous waste? What are your waste handling practices for carbon nanotubes?
Stanford’s response was thoughtful, yet very basic. The University confirmed that it follows standard laboratory safety procedures, has implemented most of the nanosafety guidelines issued by the National Institute for Occupational Safety and Health (NIOSH), and that it treats nano-waste as “hazardous waste” for disposal purposes. A summary of Stanford’s answers follows.
In response to DTSC’s first “value chain” question, Stanford responded that it has identified 16 of its laboratories that are working with carbon nanotubes. Research topics include medical applications, electronics, energy storage, fuel production, fundamental physics, and material science research. To support its “value chain” answer, Stanford attached five research papers resulting from its laboratories’ activities.
Regarding DTSC’s second “monitoring” question, Stanford answered that because there are only minimal risks of exposure and release of carbon nanotubes in its laboratories, it has not yet developed or implemented any quantitative sampling or detection methods. The University also advised that it was working with NIOSH to conduct a possible site visit of its facilities in 2010 to potentially address these issues.
Responding to DTSC’s third question concerning the “projected presence” of carbon nanotubes in the environment which may result from Stanford’s activities, the University answered that there could conceivably be (i) accidental releases and spills, (ii) routine releases from laboratory handling, and (iii) the presence of carbon nanotubes in its laboratory waste stream. Importantly, Stanford indicated that the combined use of carbon nanotubes in all of its laboratories only amounts to approximately 16 grams per year and that its nano-waste stream is treated as “hazardous waste.”
Regarding DTSC’s fourth question concerning Stanford’s knowledge of the possible environmental, health, and safety effects of its carbon nanotubes, the University responded that it takes “a precautionary, but reasonable approach” and uses good laboratory safety practices when working with nanoscale materials. Additionally, Stanford maintained that one the articles attached to its submission supports the position that carbon nanotubes are cleared from the body without adverse health effects. Finally, Stanford indicated that it closely follows the nano-EHS literature posted on NIOSH’s website, as well as the comprehensive nano-EHS website of the International Council on Nanotechnology at Rice University.
In response to DTSC’s fifth question concerning the nano-specific workplace safety measures implemented by Stanford, the University responded that (i) it follows a standard chemical hygiene plan created and implemented under existing California law, (ii) has implemented its “General Principles and Practices for Working Safely with Engineered Nanomaterials,” and (iii) has created a standard operation procedure template for use by its nano-laboratories “to assist in determining the [appropriate] levels and types of controls” which should be used in each laboratory working with nanoscale materials. Stanford’s “General Principles” document4 can be found on its website and basically summarizes the key points from NIOSH’s “Approaches to Safe Nanotechnology” document5 in a condensed bullet point format.
Finally, regarding DTSC’s sixth “hazardous waste” question, Stanford largely mooted the question by explaining that it treats its carbon nanotube waste stream as “hazardous waste,” whether or not such material actually constitutes “hazardous waste” from a scientific and/or regulatory perspective.
On the whole, Stanford put considerable effort into its response to DTSC’s information request, but it contained no “earth shattering” revelations. The University appears to be following state of the art procedures for working safely with carbon nanotubes. More importantly, there was little information in Stanford’s response that the State did not already know or could have learned with a simple telephone call. Of course, all of this begs the question of whether a formal data call in was even necessary in the first place and/or whether California is squandering its rapidly diminishing capital on this project. At the very least, the data call in should have contained a minimum threshold requirement in order to weed out minimal users and to prevent them from having to engage in the time consuming process which Stanford went through.
- Stanford University CNT Submittal Letter
- DTSC January 22, 2009, Information Request Regarding Carbon Nanotubes
- DTSC Carbon Nanotube Contact List
- Stanford's General Principles Document
- NIOSH's Approaches to Safe Nanotechnology