Lab profile: Igor Linkov, US Army Engineer Research and Development Center

The Advanced Materials Sustainability and Resilience Research Cluster at the US Army Engineer Research and Development Center (ERDC) spans multiple laboratories, structural team units, and facilities. The ERDC provides inputs into the US Science and Technology Policy through participation in the National Nanotechnology Initiative (NNI), as well as through active engagement with the Organization of Economic Cooperation and Development (OECD) and other international bodies. The Advanced Materials Sustainability and Resilience Research Cluster consists of both laboratory facilities and computational risk, as well as decision science analytical capabilities. It also connects an important public private partnership between the ERDC, multiple universities and industry. The Cluster includes the Center for Sustainable Advanced Materials, Manufacturing and Nanocomposites. 

Igor Linkov is the Senior Scientific and Technical Manager (SSTM) for the EDRC and has conducted numerous risk assessments and projects in a variety of areas including nanotechnology. He has a B.S. and M.Sc. in Physics and Mathematics from the Polytechnic Institute and a Ph.D. in Environmental, Occupational and Radiation Health from the University of Pittsburgh. Following his Ph.D., he held a postdoctoral position in Risk Assessment at Harvard University, spent 10 years consulting and over 14 years working in the Civil Service. Linkov has published widely on environmental policy, environmental modeling, and risk analysis, and is a fellow of the Society for Risk Analysis and American Association for the Advancement of Science (AAAS). In 2020, he was selected as the Laboratory Scientist of the Year by the Department of Defense and received the prestigious Arthur S. Flemming award for public service for his work on COVID-19.

Igor talked to Materials Today about his current research and future plans…

How long has the Cluster been running?

The Cluster has been running for 13 years since around 2008.

How many staff currently makes up your group?

The Cluster consists of over 35 biologists, toxicologists, geochemists, material scientists, environmental and social scientists, engineers, and technicians.

What are the major themes of research in the Center?

Our research areas, which are applicable to advanced materials, include:

• Applications and implications of nano-enabled technologies and sensors, as well as biotechnology and synthetic biology;
• Environmental hazard testing of difficult to test substances and emerging contaminants of concern;
• Environmental applications and implications of additive manufacturing including exposure assessment of ultrafine particle emissions, life cycle assessment and advanced 3D printable multi-functional composites;
• Supply chain risk and resilience of advanced materials and products, including acquisition risks and value chains;
• Risk governance and decision science for emerging biotechnologies – regulatory assessment and gaps analysis, risk assessment and governance, and characterization of ethical, legal, and social implications of emerging biotechnologies and their products.

How and why did you come to work in these areas?

Historically, ERDC was responsible for assessing the environmental impact of chemicals and explosives in complex environmental media. We were on forefront of developing methodologies for assessing the risks of legacy contaminants in aquatic and terrestrial environments. Our initial engagement started with nanomaterials but quickly broadened to include advanced materials, biotechnology, and synthetic biology.

The overarching goal of our research is to establish an innovative and sustainable competitive advantage for civilian and military developers and acquisition managers to develop and use the future’s advanced materials technologies safely in an informed manner. We aim to ensure that technology users are aware of the potential hazards of advanced materials, 3D printing technologies, nanotechnology, synthetic biology in enclosed spaces, and wear the proper PPE. We also study environmental and ecological impact of emerging technologies.

We also support the civil mission of the Army Corps of Engineers, including research and development to: (1) foster and enhance sustainable dredging missions (contaminant sequestration and detoxification); and (2) seek innovative, deployable, and retrievable advanced composites technologies for combating pest species in USACE-managed waterways without introducing legacy contamination.

What facilities and equipment does the Center have?

The facilities of the ERDC are diverse, with fully capable materials fabrication, characterization and hazard assessment.  Of particular relevance, our facilities include:

• The Environmental Toxicology Research Center (ETRC): seven large walk-in automated Darwin environmental rooms (temperature, humidity, photoperiod controlled);
• The AdvaNced & Additive Manufacturing Environmental Applications Lab (ANAMEL): polymer compounding and extrusion, 13 fused filament fabrication 3D printers, vat polymerization printers, 3D scanning, and more!
• The Polymer Nanocomposites Characterization Center (PNCC): equipment to analyze the thermal, mechanical properties of polymer composites along with microscopy analysis;
• ERDC has one of the largest supercomputers in the US, which is being used for modeling, including biotechnology applications.

Do you have a favorite piece of kit or equipment?

Many! One particular piece favored by the team includes the twin screw polymer extruder, which simplifies the creation of completely novel, 3D printable nanocomposites for rapid prototyping of unique environmental applications.

What do you think has been your most influential work to date?

The ERDC has shaped the basic principles of risk governance and ELSI (ethical, legal, and social implications) of nanotechnology, advanced materials, and biotechnology. This includes early ELSI developments though the NNI, as well as the safety-by-design and ELSI biotechnology governance strategy for the Department of Defense.

Our team led an international group of subject matter experts to write the standard guidance document that is now the internationally recognized OECD standard for how to assess the ecotoxicology of manufactured nanomaterials (published July 2020, https://www.oecd.org/officialdocuments/publicdisplaydocumentpdf/?cote=env/jm/mono(2020)9&doclanguage=en ).

Our research group generated many peer-reviewed publications in world-leading journals on the implications and applications of emerging technologies, including considerations of risk (e.g. hazard characterization and toxicity reduction strategies), governance, and ELSI. One article includes the environmental applications of 3D printed composites for passive sampling and toxicity reduction evaluation applications (https://pubs.acs.org/doi/abs/10.1021/acsestwater.0c00131 ). Another covers research output from an international NATO Science for Peace and Security Programme (SPS) Advanced Research Workshop on biotechnology and biosecurity, where we gathered feedback from dozens of participants from 24 countries regarding novel biosecurity challenges and requirements for emerging biotechnologies (https://www.embopress.org/doi/pdf/10.15252/msb.20209723 ).

What is the key to running a successful team?

I believe it is providing a high-energy work environment that fosters individual employee ownership of innovative ideas. This serves as a motivational factor that makes us want to go to work and stay engaged in multidisciplinary projects. Ultimately, the core benchmark of success is how our research is able to improve, assist, and shape governmental decision making on emerging technologies – simultaneously improving safety characterization as well as expanding their commercial potential for innumerable applications.

How do you plan to develop the Center in the future?

I would like to see the ERDC as a recognized leader in the environmental risk of advanced materials and develop the Advanced Materials Sustainability and Resilience Research Cluster with a specific DoD/USACE focus, while still considering a broader customer base. The outlook is to continue growing the Cluster as the primary one-stop-shop in the US for Army/USACE customers to assess and execute safe, rapid development and deployment of nanocomposites, 2D materials, biotechnology and synthetic biology applications including sensors from advanced manufacturing. The future is also in developing systems and materials that are sustainable and resilient to stressors, including building resilience and sustainability in the whole value chain, from production to use and end of life disposal.

Key publications

1. I. Linkov, B. D. Trump, B. A. Wender, T. P. Seager, A. J. Kennedy, J. M. Keisler. Integrate life-cylce assessment and risk analysis results, not methods. Nature Nanotechnology 2 (2017) 740-743. https://doi.org/10.1038/nnano.2017.152
2. A. J. Kennedy, M. L. Ballentine, A. Das, C. S. Griggs, K. L. Klaus, M. J. Bortner. Additive Manufacturing for Contaminants: Ammonia Removal Using 3D Printed Polymer-Zeolite Composites. ACS ES&T Water 1 (3) (2021) 621-629. https://doi.org/10.1021/acsestwater.0c00131
3. A. J. Kennedy, M. S. Hull, A. J. Bednar, J. D. Goss, J. C. Gunter, J. L. Bouldin, P. J. Vikesland, J. A. Steevens. Fractionating nanosilver: importance for determining toxicity to aquatic test organisms. Environmental Science & Technology 44 (2010) 9571-9577. https://doi.org/10.1021/es1025382
4. A. J. Kennedy, M. S. Hull, S. Diamond, M. A. Chappell, A. J. Bednar, J. G. Laird, N. L. Melby, J. A. Steevens. Gaining a critical mass: a dose metric conversion case study using silver nanoparticles. Environmental Science & Technology 49 (2015) 12490-12499. https://doi.org/10.1021/acs.est.5b03291
5. B. D. Trump, S. E. Galaitsi, E. Appleton, D. A. Bleijs, M. V. Florin, J. D. Gollihar, R. A. Hamilton, T. Kuiken, F. Lentzos, R. Mampuys, M. Merad. Building biosecurity for synthetic biology. Molecular Systems Biology 16 (2020) e9723. https://doi.org/10.15252/msb.20209723
6. E. J. Petersen, S. A. Diamond, A. J. Kennedy, G. G. Goss, K. Ho, J. R. Lead, S. K. Hanna, N. B. Hartman, K. Hund-Rinke, B. Mader, N. Manier, P. Pandard, E. R. Salinas, P. Sayre. Adapting OECD Aquatic Toxcity Tests for Use with Manufactured Nanomaterials: Key Issues and Consensus Recommendations. Environmental Science & Technology 49 (2015) 9532-9547. https://doi.org/10.1021/acs.est.5b00997
7. A. J. Kennedy, J. G. Coleman, S. A. Diamond, N. L. Melby, A. J. Bednar, A. Harmon, Z. A. Collier, R. Moser. Assessing nanomaterial exposures in aquatic ecotoxicological testing: framework and case studies based on dispersion and dissolution. Nanotoxicology 11 (4) (2017) 546-557. https://doi.org/10.1080/17435390.2017.1317863
8. A. Kennedy, J. Brame, T. Rycroft, M. Wood, V. Zemba, C. Weiss Jr., M. Hull, C. Hill, C. Geraci, I. Linkov. A Definition and Categorization System for Advanced Materials: The Foundation for Risk-Informed Environmental Health and Safety Testing. Risk Analysis 39 (8) (2019) 1783-1795. https://doi.org/10.1111/risa.13304
9. E. Alberts, M. Ballentine, E. Barnes, A. Kennedy. Impact of metal additives on particle emission profiles from a fused filament fabrication 3D printer. Atmospheric Environment 244 (2021) 117956. https://doi.org/10.1016/j.atmosenv.2020.117956
10. B. D. Trump, J. M. Keisler, S. E. Galaitsi, J. M. Palma-Oliveira, I. Linkov. Safety-by-design as a governance problem. Nano Today 35 (2020) 100898. https://doi.org/10.1016/j.nantod.2020.100989
11. M. E. Bates, J. M. Keisler, N. P. Zussblatt, K. J. Plourde, B. A. Wender, I. Linkov. Balancing Research and Funding using Value of Information and Portfolio Tools for Nanomaterial Risk Classification. Nature Nanotechnology 11 (2016)  198–203. https://doi.org/10.1038/nnano.2015.249