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Career of the Month

Radiochemist Catherine Riddle

Radiochemists study radiation from an atomic and molecular perspective, and find ways to harness the power of radioactive chemical reactions. Some radiochemists focus on basic or theoretical research, whereas others apply their knowledge in industry sectors such as medicine or nuclear power generation. Catherine Riddle is a senior research scientist focusing on radiochemistry at Idaho National Laboratory (INL) in Idaho Falls, Idaho. She has eight patents and six more pending.

Work Overview

My research work at INL involves developing new technologies to solve national and global problems, in areas such as used nuclear fuel recycling, nuclear national security and environmental science. Some of my technology-based patents include enabling environmental petroleum cleanup, detection of special nuclear material entering the United States, and a rapid chemical detection process to protect first responders, taking advantage of visible color changes in the presence of very low concentrations of uranium and plutonium during radiological events. A typical day is full of what-ifs and problem solving. Being a scientist or engineer is a team sport, so we assemble teams that bring the best and brightest in different areas together to solve each problem.

Seeing a problem on the news, such as the Deepwater Horizon explosion and oil spill, and thinking, “There has to be a way to fix this,” starts the mind working. I start researching an idea for a solution, using tools such as literature searches and experimentation, and then gather a team of the best people to work on the solution. After that, I propose funding. Sometimes it can take many months to refine the idea and get it funded. After securing funding, my team and I are in the lab, experimentally researching the idea. Depending on the idea, it can take years to find an answer. There are disappointments from failed experiments, but there are also successes.

I enjoy the excitement that comes with getting a novel idea funded and researched, and then seeing it used in real-world applications that help humanity or our planet. My least favorite part of my work is paperwork. However, I can turn to other people at INL who have the education and skills to help me with form or proposal issues.

Career Highlights

My most memorable moments include working with colleagues, taking research from ideas to real-world technologies, mentoring interns and staff members, and conducting outreach on STEM topics. I consider my most recent technology, CoDeAc (Colorimetric Detection of Actinides) among my best achievements, because it helps first responders stay safe during radiological accidents or terrorism events. Paying forward the mentoring that I once received has also been important.

Career Path

I loved chemistry from an early age, but it took me many years to see it as a career. My path was neither traditional nor easy. After high school, I attended community college for a year, but without a mentor or knowing what I wanted to be when I grew up, I just drifted through courses aimlessly. I then worked minimum-wage, service-oriented jobs. I eventually taught myself how to do floral arranging, but I still was making barely over minimum wage and working long hours. Through that work, I met a woman who had been a chemist, and we started talking about her career path and work. I realized she was no smarter than I am, and I started to remember my positive high school chemistry experience. So I decided to change my life and become a chemist.

At age 36, I returned to college, enrolling in the chemistry program at Idaho State University (ISU). I rode the bus to campus on the first day, with high hopes. However, after finding myself in a large room full of 18-to-20-year-olds, I started to question my decision. Waiting for the bus home, alone and sobbing, I thought, “What am I doing here with all these kids? I can’t do this.” Then I heard a little voice deep inside say, “Come back tomorrow.” With mixed feelings, I went back the next day, and by the end of the week, I could not imagine being anywhere else. The courage I found that day (and many days from then on) has helped me countless times during my career and in life.

While finishing up my studies, I began a summer internship at INL. My advisor had introduced me to radiochemistry, and the INL apprenticeship gave me a passion for the field. My husband and I paid for my schooling ourselves, along with student loans, so I needed to get working right after graduation. I was hired as a full-time junior research scientist at INL, to work on national and international research projects. INL encourages staff to continue their education, so I went back to school while still working full time, to get a master’s degree and a PhD. That was a challenge, but manageable.

Knowledge, Skills and Training Needed

I am an inventor, teacher, and dreamer. I acquired my chemistry and radiochemistry skills and training through my university education, which taught me how to think. Thinking and looking at problems analytically—meaning seeing all parts of a problem and being able to define each part as it relates to the other—is the most important skill to learn. Math is also important, but a chemist’s math skills are more arithmetic than calculus. I’ve been able to become a better scientist since then because of the knowledge I’ve obtained on the job, through my work and through my colleagues. I also credit my career success to a mentor who took the time to teach me not only to be a world-class radiochemist, but also a world-class mentor.

Imagination is where ideas are born. Patience and courage are also required, whether you’re trying to understand equations for a school science exam, or you’re a scientist working through a difficult stretch with a thousand failed experiments on a promising technology that could change the world as soon as it works.

Advice for Students

Never stop learning, embrace your imagination, and don’t be too hard on yourself. Many consider science and engineering too difficult because of the math. But once you see the math from an everyday standpoint (e.g., mass, volume, and density applied in cooking), it will make sense, and from there, more difficult calculations can be designed and understood. Scientific notations will also make more sense when you start using them in real-world applications.

Bonus points

Riddle’s Education: BS in chemistry, Idaho State University; MS in chemistry, University of Idaho; PhD in radiochemistry, University of Nevada, Las Vegas

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Related Careers: Health physicist, chemistry technician, chemical engineer, nuclear engineer, nuclear operator

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