New Analytical Method for Determination of Phthalates in Wastewater by on Line LC-GC-MS Using the TOTAD Interface and Fraction Collector

There is an increasing demand for automatic, reliable and sensitive analytical methods for determining trace levels of phthalic acid esters (PAEs) in environmental samples. While on line coupled liquid chromatography-gas chromatography (LC-GC) has been proof to be a powerful tool for trace-level analyses in complex matrices, the present work presents a new totally automated on line LC-GC method, using the Through Oven Transfer Adsorption Desorption (TOTAD) interface, for the analysis of four of the main phthalates, dibuthyl phthalate (DBP), diethyl phthalate (DEP), dimethyl phthalate (DMP) and diethylhexyl phthalate (DEHP), in a matrix as complex as leachate. The sample is directly injected into the LC injector valve with no sample pretreatment other than simple filtration. The LC step separates the target analytes from matrix interference. Two different LC fractions are collected in a purposely designed fraction collector and then transferred to the TOTAD interface, which concentrates the analytes, totally eliminates the solvent and transfers the analytes to the GC-MS system, where the analysis is carried out. The LOD of the method varied from 0.1 µg/L (DEHP) to 1.4 µg/L (DMP), RSD for retention time below 0.14% and for absolute peak areas below 12% and linearity from 1 µg/L to 1000 µg/L (R2 > 0.99), except in the case of DEHP (linearity from 1 to 250 µg/L, R2 = 0.94). The method was applied to the analysis of the target analytes in samples collected from a municipal solid waste (MSW) landfill in Rosario (Argentina).

AN ASSESSMENTOF PHTHALATES IN COSMETIC PRODUCTS BY DISPERSIVE LIQUID-LIQUID EXTRACTION METHOD USING HPLCAND LC-MS/MS

A Dispersive liquid-liquid microextraction (DLLME) based analytical method was developed and validated using HPLC-PDA and LC-MS/MS for quantitative determination of phthalates (Dimethyl phthalate (DMP), Diethyl phthalate (DEP), Benzyl Butyl Phthalate (BzBP), Dibutylphthalate(DBP), Diethylhexyl phthalate(DEHP), Di-n-octyl phthalate (DOP) in different cosmetic products (After Shave Lotion, Deodorants, Perfume and Liquid Body Lotion). The DLLME based developed and validated analytical method was found specific, sensitive, accurate and precise. The accuracy (% recovery) of the method at a spiking level of 0.1, 0.5 and 1.0 mg L-1 in the different cosmetic product was found in the range of 92-108. The interday and intraday precision (%RSD) of the method was found less than 15. Out of six analyzed phthalates, only four phthalates were detected in different cosmetic products. Dimethyl phthalate (DMP) and Di-n-octyl phthalate (DOP) were detected in aftershave lotion. Diethyl phthalate (DEP) was detected in deodorants. Dibutyl phthalate (DBP) and Diethyl phthalate (DEP) were detected in perfumes. None of the phthalates were detected in liquid body lotion.