Direct soil analysis by paper spray mass spectrometry: Detection of drugs and chemical warfare agent hydrolysis products

•Soil was analyzed by paper spray mass spectrometry.•Chemical agent breakdown products and drug residues could be detected at low part-per-billion levels.•Three different types of soil were tested.•Analysis time was about 1 min; no offline sample preparation was required.•To improve quantitative analysis, an offline sample prep method with internal standardization was also investigated.