Strategies and Techniques for Identifying Target and Non-target Compounds in Environmental Samples

Oral Presentation

Prepared by E. Reiner, K. Jobst, L. Haimovici, D. Megson, M. Pena-Abaurrea, A. Muscalu, L. Shen
Ontario Ministry of the Environment and Climate Change, 125 Resources Road, Toronto, Ontario, M9B 5R3, Canada

Contact Information:; 416-235-5748


There are approximately 100,000 industrial chemicals or chemicals of commerce used currently, but only a small fraction are monitored routinely [1]. The Stockholm Convention on persistent organic pollutants (POPs) targets 24 halogenated organic compounds or compound classes. Environmental samples contain hundreds or thousands of non-targeted compounds, some of which may pose a risk to the environment or human health. Their identification can be very challenging because most routine analytical techniques are transparent to non-targeted compounds.

High-resolution mass spectrometry (MS) and multidimensional gas chromatography (GCxGC) are complementary analytical techniques for target and non-targeted analysis of environmental samples. Full scan mass spectral scanning allows for the analysis of target and non-target compounds in the same sample. Automated software can be used to target specific compounds and techniques like scripts or mass defect plots with high-resolution mass spectrometry can be used to identify and quantify non-target compounds. Multidimensional chromatography offers enhanced separating power to produce clean mass spectra for quantifying target compound and to improve the ability to interpret mass spectra for identification of unknown compounds.

Target compounds like dioxins, polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs), organochlorine pesticides (OCPs), polychlorinated naphthalenes (PCNs) and polycyclic aromatic hydrocarbons (PAH) can be grouped together. A subset of the each analyte group (signature compounds) can be used to screen for the presence of the group. Data review using scripting and mass defect plots can be used to identify additional compounds either by suspect screening (non-routine or non-target compounds used in industry or commerce) or unknown compounds.


[1] Muir, D. C. and Howard, P. H., Environ. Sci. Technol., 40(23), 7157-7166, 2006.