HPLC and GC Environmental Testing Techniques
Rachel Muenz talks with Terry Cain and Dr. Michael Wichman about environmental testing using HPLC and GC
Terry G. Cain is a supervisor in the Environmental Health Division of the State Hygienic Laboratory (SHL) at the University of Iowa (UI). He received his degrees in chemistry and computer programming from Loras College, Dubuque, Iowa. He has worked in the areas of agricultural chemistry, radiochemistry, drugs of abuse testing, quality assurance, emergency response, laboratory information systems, and environmental monitoring with emphasis in gas chromatography in conjunction with mass spectrometry.
Dr. Michael D. Wichman has been with the SHL at UI since 1987 and currently is the director of the Environmental Health Division and the associate director of SHL. His education is in chemistry, with a doctorate in analytical chemistry from Kansas State University. His current research interests include simplifying sample preparation techniques, environmental monitoring for pesticide and industrial chemical degradates, and biomonitoring for human metabolites resulting from environmental exposure.
Q: What environmental work does the State Hygienic Laboratory at the University of Iowa do?
A: Wichman: We perform analytical testing to support numerous local and state agencies, including local county health departments, the Iowa Department of Natural Resources, the Iowa Department of Public Health, the Iowa Department of Inspections and Appeals, the Iowa Department of Homeland Security and Emergency Management, and others. We’re involved in the testing of ambient air and surface water, groundwater, drinking water—both public and private water supplies—wastewater, plant materials, soils, sediment, and various other matrices. A lot of those tests are driven by various regulations like the Safe Drinking Water Act; Clean Water Act; Clean Air Act; Federal Insecticide, Fungicide, and Rodenticide Act; and the Resource Conservation and Recovery Act. We’re also part of several emergency response networks at the federal level for the CDC [Centers for Disease Control and Prevention], EPA [US Environmental Protection Agency], and FDA [US Food and Drug Administration].
A: Cain: In addition, we consult with and perform testing for private citizens. So if a person has a private well and they have a problem or just want to check the integrity of their well, we can assist them. We also collaborate, usually on a project- by-project basis, with researchers from the University of Iowa, Iowa State University, and private colleges in the state.
Q: What specific things do you use HPLC and GC for?
A: Cain: Many people around the state know us for our drinking water testing. Part of that program includes testing for disinfection by-products formed when drinking water is chlorinated. We test for trihalomethanes by GC-MS, and we test for haloacetic acids, which are another set of disinfection by-products, by GC electron capture. Our robust air-testing program involves both LC and GC. We have a network of air-monitoring sites that we support, and we send canisters and cartridges out to those sites for collection of ambient air. The samples are returned to the laboratory for determination of tailpipe emission hydrocarbons and for toxic volatile organic compounds by GC-MS. The cartridge samples are used to determine carbonyl compounds by LC.
A: Wichman: We also look for other volatile components, such as things in gasoline—benzene, toluene, ethyl benzene, the xylenes (BTEX), and semivolatile organics such as polycyclic aromatic hydrocarbons, which were analytes of interest in the Gulf of Mexico oil spill. Our lab performs determination of pesticides and pesticide degradates, acid herbicides, nitrogen phosphorus herbicides, insecticides, rodenticides, fungicides, and other compounds such as personal care products and pharmaceuticals by both GC and LC technologies.
A: Cain: Often different pesticides require different methodologies, so we have numerous tests and procedures that we support. Different extraction procedures as well as different analytical procedures may be required, depending on the particular chemical class. Acid herbicides require a different procedure from the nitrogen phosphorous pesticides, for instance. So there’s quite a variety. A lot of the pesticide work is surface water monitoring. Samples may be obtained from wetlands, rivers, lakes, streams, or groundwater.
Q: What challenges does your lab experience in HPLC and GC testing?
A: Cain: Much of what we do is routine work—drinking water, for instance— but the challenging work comes with more complex matrices. The past couple of years we’ve been doing more fish analysis, so preparing a fish sample to be able to do the analysis can be difficult. Sometimes we’ll get a whole fish that may be relatively large. We grind the fish, measure the fat content, figure out how to do the cleanup on the tissue, then do the extraction and the analytical work. We’re looking for contaminants at partsper- billion levels or even lower, so that’s a challenge. Other tissue matrices are always a challenge too.
Q: How do you handle those challenges?
A: Cain: We have high expectations of our staff, and fortunately our staff has a lot of experience, so it’s pretty unusual that we get something that we’ve never seen before. Usually we put our heads together and come up with a plan; sometimes it’s on an individual sample basis. We try to figure out what’s the best technique or what’s the best way to go about problem-solving the difficult matrix. Another challenge is that we have different platforms that the instruments operate on. There are multiple software systems that analysts have to be familiar with, and then maintaining those different platforms is a challenge, but again I go back to our staff. They’re experienced, and without that experience, we’d have a much more difficult time.
A: Wichman: Some of the other issues that we face are trying to maintain our current equipment and trying to obtain new technology with limited resources. It’s a challenge to get some of the latest and greatest, like high-resolution mass spectrometers. That would be useful to us for things like the PCBs [polychlorinated biphenyls] and PBDEs [polybrominated diphenyl ethers] congeners, but we don’t have that technology and really can’t afford to purchase it. Service contracts are also getting more and more expensive. We do maintain a quality management system in our laboratory to ensure that staff completing tests have met their demonstration of capability. That’s documented, and results are checked and validated. I won’t say we never make mistakes, but we keep that to an absolute minimum.
Q: What changes do you expect to see in the future for your lab?
A: Cain: There’s always going to be the need for new tests and new requirements and the need to detect lower and lower levels of contamination. I don’t expect that’s going to stop. There will also continue to be a need to respond to different environmental situations quickly—if there’s a spill or a fire, for example, like the one we had at a nearby landfill a couple of years ago. To be able to respond to those unforeseen events more quickly will continue to be important.
A: Wichman: We’ve experienced a number of floods here, and of course, being able to see what people may or may not have been exposed to is important. So is a quick turnaround on those tests. During the 2008 flood, we were able to meet that demand, but it was a challenge. We had to implement an incident command structure to make sure we could keep things staffed and perform those tests in a timely manner. Some of the other changes I think we might see involve technology. A lot of things are moving to mass spec or tandem mass spec. MALDI-TOF is another emerging technology that we’d really like to look at.
Q: What key advice would you have for labs that are just getting into environmental testing and may be new to HPLC and GC?
A: Wichman: It depends on what program they’re getting into. If they’re getting into drinking water, for example, they should read through those methods and make sure they understand what the methods require. Then they should implement a quality management system based on either The NELAC Institute (TNI) or ISO 17025 standards, something to make sure that they have implemented a quality control system. That can save a lot of time. Our standard operating procedures are written, and methods are validated. Cross-training is important as well so you have some flexibility, depending on the size of the laboratory. With us—whether we’re dealing with floods or a landfill fire—we have to be able to quickly shift our focus and address those issues.
A: Cain: With the quality assurance aspect, there’s a cost to setting all that up, but it’s really necessary. You really have to be thorough on that aspect and find good people who do good, careful work in a conscientious manner and train them well.
Q: Did you have anything more to add?
A: Cain: We’ve had a major effort here in developing and enhancing our laboratory information management system [LIMS]. I think a critical component for any lab is to have a good information management system that can be maintained. There are mountains of data that we produce, and keeping all of that organized in an information system is really, really important.
A: Wichman: Being able to track the quality control is essential so you can see [whether] something is off— whether it’s the instruments drifting or whatever—you need to be able to track that. Something we’ve done here is interfacing our instruments directly into our LIMS, which saves a lot of manual data entry. That would be something that would be good for a new lab getting into this. It’s expensive, but it would be a good thing for them to consider.