Identifying the Potential Environmental Impacts of Engineered Nanomaterials
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Rochester Institute of Technology RIT Scholar Works Theses 1-2016 Identifying the Potential Environmental Impacts of Engineered Nanomaterials Therese Garvey [email protected] Follow this and additional works at: https://scholarworks.rit.edu/theses Recommended Citation Garvey, Therese, "Identifying the Potential Environmental Impacts of Engineered Nanomaterials" (2016). Thesis. Rochester Institute of Technology. Accessed from This Dissertation is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. Identifying the Potential Environmental Impacts of Engineered Nanomaterials By Therese Garvey A DISSERTATION Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Sustainability Department of Sustainability Golisano Institute of Sustainability Rochester Institute of Technology January 2016 Author:_________________________________________________________________ Sustainability Program Certified by:_____________________________________________________________ Dr. Gabrielle Gaustad Associate Professor of Sustainability Program Approved by:____________________________________________________________ Dr. Thomas Trabold Department Head of Sustainability Program Certified by:_____________________________________________________________ Dr. Nabil Nasr Assistant Provost and Director, Golisano Institute for Sustainability and CIMS Identifying the Potential Environmental Impacts of Engineered Nanomaterials By Therese Garvey Submitted by Therese Garvey in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Sustainability and accepted on behalf of the Rochester Institute of Technology by the dissertation committee. We, the undersigned members of the Faculty of the Rochester Institute of Technology, certify that we have advised and/or supervised the candidate on the work described in this dissertation. We further certify that we have reviewed the dissertation manuscript and approve it partial fulfillment of the requirements of the degree of Doctor of Philosophy in Sustainability. Approved by: Dr. Gabrielle Gaustad__________________________________________ (Committee Chair and Dissertation Adviser) Dr. Callie Babbitt __________________________________________ Dr. Eric Hittinger __________________________________________ Dr. Christy Tyler __________________________________________ SUSTAINABILITY PROGRAM ROCHESTER INSTITUTE OF TECHNOLOGY January 2016 ii ABSTRACT Golisano Institute for Sustainability Rochester Insititute of Technology Degree Doctor of Philosophy Program Sustainability Name of Candidate Therese Garvey Title Identifying the Potential Environmental Risks of Engineered Nanomaterials Engineered Nanomaterials (ENMs) are increasingly manufactured and incorporated into a diverse array of consumer products and industrial uses. While ENMs are touted for their technological and efficiency benefits, the potential impacts of increasing emissions and exposures to ENMs are poorly understood. This dissertation takes a critical look at the current knowledge in impact assessment of nanomaterials. First, the current metrics for impact assessment of traditional methods are compared with the proposed set of metrics necessary for nanomaterial impact assessment. Next, in order to understand the potential environmental impacts in context, characterization factors for four case study nanomaterials are modeled using physicochemical data from literature sources and adjusting the USEtox method as necessary. Then cradle-to-gate life cycle assessments are performed for the production of case study nanomaterials to understand the primary drivers of environmental impact. Last, the larger context of nanomaterial production is considered by forecasting a potential use of CNTs in lithium ion batteries over the next 25 years. Current policy issues are discussed within a life cycle context for the nano-enabled lithium ion battery. iii The results demonstrate that in most cases nanomaterials do not contribute a significant impact to the total in LCA. In contrast, energy production for these materials is found to be the primary driver of impact in cases where inherent nanomaterial toxicity is low. Electric vehicles and energy storage were found to be the primary drivers of CNT production for lithium ion batteries in both forecasted scenarios, indicating that despite the current debate over how to use toxic chemical regulations to best control risk, regulations over electricity and energy production could better target the overall environmental impact in most cases. Furthermore, there is potential for future regulations to incorporate novel metrics so that life cycle impact assessment can inform environmental policy. iv ACKNOWLEDGEMENTS I would like to express my very great thanks to my academic adviser, Dr. Gabrielle Gaustad, for allowing me this opportunity, helping me find a meaningful field of research and pushing me forward throughout the past years. I absolutely could not have achieved this without your guidance. Thanks also to Dr. Callie Babbitt for your always valuable and insightful feedback. Advice given by Dr. Eric Hittinger and our external examiner Dr. Christy Tyler was also instrumental to the contributions to the final product. Next, thank you to the Office of Pollution Prevention and Toxics at the US EPA for giving me the incredible experience of putting into practice the sustainability coursework and research during my internship. Thanks especially to my mentor, Phil Sayre, for exposing me to many more valuable resources in my field and for his continued support and guidance. Last, thank you to my friends in GIS, especially Xue Wang and Lourdes Gutierrez, for being my allies in the office and out, my friends outside of GIS for helping me decompress. Last, thank you is due especially to my family for their constant love and support. v TABLE OF CONTENTS List of Figures …………………………………………………………………………..IX List of Tables …………………………………………………………………………….X Chapter 1. Introduction ……………….………………………………………………….1 1.1 Introduction to Nanomaterials ………….……………………..…… ……. 1 1.2 Risk Assessment ……………………..…… ………………………………… 2 1.2.1 Risk Assessment Steps…………….……………………………..4 1.2.2 Methodological Challenges to Risk Assessment………………….4 1.3 Impacts of Nanomaterials………………………………………………...7 1.3.1 Key Parameters for Nanomaterial Impact Assessment …………10 1.4 Policy Implications ……………………………………………….…….13 1.5 Motivation …………….……...…………………….……….……….…15 Chapter 2. Categorizing the Primary Factors of Ecotoxicity in Nanomaterial Production ……………………………………………………………… 17 2.1 Introduction ……………………….…………………………………… 17 2.2 Methods……………….………………………………………………… 19 2.2.1 Life Cycle Assessment Modeling …………………….…………19 2.2.2 Case Study Selection…….……….……….……….……….……19 2.2.3 Life Cycle Inventory Development..…………………….………22 2.2.3 Impact Assessment Methods…………………….……………… 24 2.3 Results ………………………………..…………………………………29 2.3.1 Toxic Potential: Characterization Factor Results ……………… 29 vi 2.3.2 Total Ecotoxicity Results ………………………………………31 2.3.3 Evaluating the Tradeoff Between Ecotoxicity and CED ………34 2.3.4 Using Nanomaterial Toxicity Characteristics to Forecast Policies.. ………………………………………………………………… 38 2.4 Discussion and Future Work……………………………………………43 Chapter 3. Regulating Nano-Enabled Products: Implications for energy storage technologies ……………………………………………………………. 46 3.1 Introduction………………………………………………………………46 3.1.1 Case Study Motivation …………………….…………………… 47 3.2 Methods……………….………………………………….………………51 3.2.1 Case Study Method: Material Flow Analysis .………………… 51 3.2.2 Life Cycle Impact Assessment …………………….……………59 3.2.3 Policy Discussion …………………….………………….………60 3.3 Results and Discussion……………………….…………………….……60 3.3.1 Case Study Results……………………….………………………62 3.3.1.1 CNT Volumes ………………….……………… 62 3.3.1.2 Life Cycle Impact Assessment ………………… 64 3.3.4 Metrics Discussion …………………….………………………67 3.3.3 Case Study Policy Discussion …………….……………………69 3.3.3.1 Regulating Nanomaterial Emissions ……………69 3.3.3.2 Regulating the life cycle impacts of nanomaterial production ………………………………………75 3.4 Conclusions and Future Work ……………………….…………………76 Chapter 4. Conclusion……………………….……………………………………..78 vii Appendices ……………………….………………………………….…………………80 A. Nanotoxicology Results Tables ………………………….……………80 B. Surface Coatings and Functionalizations Table …….……………….…87 C. Substance Data Table ….……………….…………………….…………88 D. Ecotoxicity Results……………..……………………….………………89 References………………………….………………………………….…………………96 viii LIST OF FIGURES 1.1 Risk Management Paradigm ……………………………………………………3 1.2 Environmental Impact: Categories and the Subcategories ………………………8 2.1 General Scope for LCA Modeling of the Four Case Study Nanomaterials …… 22 2.2 Categorization Flowchart Translating LCI into Drivers of Impact.……………24 2.3 USEtox Method Theory and Adaptation .…………………………………… 27 2.4 Characterization Factor Results.…………………………………………………31 2.5 The Ecotoxicity Results by Percent Contribution for All Materials and in All Scenarios…………………………………………………………………………32 2.6 Ecotoxicity Results for Carbon-based Materials ………………………………33 2.7 Correlation Results………………………………………………………………35 2.8 Paradigm for Projecting Regulations for Nanomaterials ………………………39 2.9 Number of Nanoproducts in the Consumer Products Inventory and the Pathway Through Which Exposure is Expected………………………………………… 41 2.10 Permissible and Recommended Exposure Limits for Particulates, Fumes and Fibers ……………………………………………………………………………42