Environmental Analysis

In the last year the Gulf oil spill has brought environmental analysis into the headlines; as other new ways are found to challenge how separation science is used in the environment, what is being done to keep up?

Joining us for this technology forum on the current state of environmental analysis are Dr. Markus Läubli of Metrohm and Sky Countryman of Phenomenex.

What do you think has had the biggest impact on environmental analysis in the last year?

Läubli:I do not see big individual impacts. It is the growing importance of environmental analysis as such. In the past, a really new technology has not emerged, nor has there been a new hype such as, the much discussed and investigated bromate or perchlorate topic.

Countryman: The biggest impact has to be the oil spill in the Gulf. Labs scrambled to develop methods to analyze for PAHs, hydrocarbons, and the dispersants used in the clean up effort. Specialized tests were developed to help characterize the oil being found in the gulf region and help determine if it was the result of this spill or another source. This also affected the sample preparation aspect of environmental sampling because of the large number of samples that now have high concentrations of salt in the matrix. Working with the complications of this matrix has required changes in sample handling and processing.

What are the current challenges that environmental analysis poses to separation scientists?

Läubli: The most important issue by far, is not the analysis itself but rather the sample preparation procedure. Most analysis errors are attributed to manual sample preparation. Therefore, my company promotes the use of fully automated inline sample preparation. This saves labor, ensures traceability, and improves accuracy and reproducibility of the results.

Countryman: Lower detection limits are posing one challenge. Labs are detecting lower levels of compounds to meet EPA requirements as well as to remain competitive. These lower detection limits are pushing methods, extractions, and instrumentations to new limits. Separation scientists are also adding extra compounds to current analyte lists to become more diverse and competitive. These additional compounds include appendix IX for semivolatile analysis as well as specific isomers of commonly analyzed compounds like DDD, DDT, DDE, other pesticides, PAH isomers, and more thorough identification of complex mixtures like chlordanes, Aroclors, and toxaphenes.

Are advances in technology making it easier to comply with methods laid down by regulatory agencies? How are techniques and instrumentation keeping up with regulation?

Läubli: Advances in technology sometimes make it even more difficult to comply. Many standards are based on older technology and a lot of time is required to bring in new technology into standards. Many standards are still mentioning brand names instead of technology.

By employing the actual accomplishments in instrument technology, especially by using intelligent system components, issues such as traceability in regulated environments would not be as big a challenge as they are now.

Countryman: There have been some advances in GC and GC–MS instrumentation and column technology that are addressing common environmental lab concerns such as sensitivity, sample throughput, and calibration stability. Newer GC ovens heat and cool faster allowing for method run times to be reduced. The latest quadrupole MS systems offer lower detection limits making it easier for quantification at the low levels required by the new regulations. Column manufacturers are working to develop phases that improve peak shape for acidic and basic compounds allowing for improved quantification, especially at the low level. These improvements also lead to better column ruggedness, which impacts calibration stability.

Keeping up with regulation may require moving techniques from traditional MS to TOF or even LC–MS–MS to gain better sensitivity. This will require large capital investments that may be prohibitive. These new systems also require skilled operators that must understand how to make full use of these new high powered instruments. In the short term, improvements in sample preparation techniques allow for more much lower detection limits. Using techniques like solid-phase extraction (SPE) can help remove inferences while simultaneously concentrating the sample by several orders of magnitude.

What do you think the future holds for environmental analysis?

Läubli: This is just a never-ending story. The monitoring of water quality especially will require increased testing. The desalination process will become even more important to ensure the future water supply.

Countryman: As the governments around the world learn more about the ways environmental contaminants affect our population, the number of compounds that must be monitored will grow and the levels at which they must be controlled will be lower. These new contaminants will require a shift from traditional instrumentation to more sensitive and comprehensive techniques provided like TOF, LC–MS–MS, or even GCxGC. The separation of a greater number of compounds will also require more selective GC and HPLC phases as well as new sample preparation techniques.

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