Phthalates are molecules used in industry as plasticisers, however, they represent a potential health risk for the human population. Several phthalates are classified and controlled under the EU regulations and thus it is important to evaluate their concentration in daily use products.
Ion mobility spectrometry (IMS) is a technique suitable for real-time phthalate analysis. To understand the ion chemistry in the IMS, we used the IMS-MS and the SIFT-MS methods to study reactions of dimethyl phthalate, dimethyl isophthalate, dimethyl terephthalate, diethyl phthalate and dipropyl phthalate with the hydronium, H3O+ , reagent ions at variable humidity.
Different isomerisation of the studied phthalates strongly affects formation of water clusters. No water clusters production was observed for 1,2 position of phthalate esters, which positively affect selectivity of identification of phthalates.