Last decade has witnessed the resurgence of occasional terror attacks or extreme events,which poses a serious threat and impediment to public security and ecomonic development.To faciliate the first emergency response,the on site monitoring and detection techniques are urgently needed,and attracting great attention in the field of analytical science.Among various analytical techniques,ambient ionization mass spectrometry(AIMS) once emerged,it is rapidly developing in prosperity due to its powerful ionization capability under atmospheric conditions.Taking advantages of rapid,in situ,real time,high throughput analysis of samples in complex matrixes with simple or no need of sample preparation,AIMS is regarded as a current research hotspot in the analysis of chemical toxicants in the field of public security.According to the ionization and desorption behaviors,AIMS was classified into two categories in this review,containing one step ambient ionization or two step ambient ionization approach.The bibilometric results were then analyzed and presented via VOSviewer software from network visualization of countries,institutions,authors and keywords of recent publications with a total of 2 685 articles.Seven key word clusters were clearly extracted to indicate different technical features and application trends.The representative AIMS techniques were then mainly summarized,as well as their application examples in the detection of illicit drugs,explosives,chemical warfare agents and biotoxins as the main targets.In the present public security field,abundant ambient ionization modes have been adapted to different types of mass analyzers for qualitative and quantitative detection of trace chemical toxicants in complex sample matrices such as body fluid,surface and food.For sensitive screening and detection,researchers devoted to improving ionization efficiency,desorption ability,and integrating simple sample pretreatment.In particular,ambient ionization could be organically combined with miniaturized ion trap mass spectrometry that does not require high vacuum to achieve a rapid and on site detection,of which the promising AIMS techniques include dielectric barrier discharge ionization(DBDI),direct analysis in real time(DART) and paper spray ionization(PSI),etc.Along with the impressive progress of AIMS,a series of technical challenges still need to be effectively addressed,including reproducibility,quantitative ability,analyte scope,sensitivity and complex data analysis capabilities.It is foreseeable that AIMS will realize its great potential in public security field,especially in on site detection under the deep understanding of theory,beneficial to its flexible module design and powerful hybridization or combination potential with other detection techniques.