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Mass spectrometric analysis, often performed using data (in)dependent acquisition (DIA and DDA), is widely used for metabolomics and proteomics-based studies. The exposome is the measure of all environmental exposures during the course of a lifetime. This concept was developed to complement other omics-based research by obtaining a more comprehensive assessment of exposure to environmental risk factors, including environmental toxicants. There is a critical need for highly sensitive analytical techniques capable of non-targeted screening (NTS) of environmental toxicants. This contribution reports on the combination of atmospheric pressure gas chromatography-quadrupole time-of-flight mass spectrometry (APGC-QTof) with a SONAR, a recently developed DIA mode. SONAR utilizes a narrow, scanning quadrupole window to reduce spectral complexity and increase the yield of identifiable toxicants in environmental and biological samples. The technique was evaluated using a mixed standard containing 25 different halogenated compounds as well as dust samples from recent inter-laboratory studies designed to evaluate the efficacy of NTA methodologies. The use of structure library searches as well as experimental and computationally generated spectral libraries for compound identification will also be explored.