Optimisation of pressurised liquid extraction by experimental design for quantification of pesticides and alkyl phenols in sludge, suspended materials and atmospheric fallout by liquid chromatography-tandem mass spectrometry.

The study proposes an analytical method to quantify 10 alkylphenols and 12 pesticides at ultra-trace levels by liquid chromatography in reverse mode coupled to positive electrospray ionisation-tandem mass spectrometry. The extraction procedure from environmental solids was optimised by pressurised liquid extraction using acetonitrile:isopropanol (1:1, v/v). The influence of several extraction experimental factors, temperature, pressure, duration and number of cycles, related to the PLE was investigated by an original and efficient chemometric approach. The optimised extraction method (80 degrees C, 40 bar, 10 min, 1 cycle) exhibited recoveries between 67 and 127% with RSD mostly under 13%. The whole method was applied to real samples: sludge, suspended materials, atmospheric fallouts and roof deposit. Pollutant levels were between 1 microg kg(-1) and 5.9 mg kg(-1).

Multiresidue analytical methods for the ultra-trace quantification of 33 priority substances present in the list of REACH in real water samples.

Innovative and simultaneous multiresidue analytical methods of 33 multi-class pollutants in wastewaters, surface and ground waters, using solid phase extraction (SPE) followed by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) are presented. Target compounds include several groups of emerging and persistent contaminants derived from the European priority list of the registration evaluation and authorisation of chemicals system (REACH): organochlorine (8) and organophosphorus (2) pesticides, carbamates (2), fungicides (8), phthalates (2), alkylphenols (10) and bisphenol A. The recovery rates of the SPE gave levels ranged from 84 to 118% with exception of some compounds that yielded lower (methamidophos (50%), p,p'-DDT (60%) and o,p'-DDT (72%)) but all recoveries were acceptable. Low limits of detection (LOD) varied between 0.2 and 88.9 ngL(-1) (except for HPTE and 4n-octylphenol giving 161 and 220 ngL(-1), respectively). A study of matrix effects was performed in order to evaluate the best and reliable calibration approach. The developed analytical method was successfully applied to the analysis of the 33 substances in wastewater effluents as well as surface and ground waters. The most frequently detected families were alkylphenols and industrial endocrine disrupting compounds (phthalates and bisphenol A).

Analytical methods for the determination of selected steroid sex hormones and corticosteriods in wastewater.

An analytical method for the determination of 12 selected estrogens, progestagens and corticosteroids is presented. The optimization of the method, including liquid chromatography separation, extraction on a solid phase, purification on a silica gel cartridge and detection by mass spectrometry, is described. Both the repeatability, with relative standard deviation ranging from 1.4 to 2.7%, and the accuracy, with recoveries ranging from 92.7 to 102.4%, were very satisfactory for ten of the target analytes. The limits of detection were lower than 1 ng/L for progestagens, androgens and corticosteroids, and ranged between 0.9 and 4.3 ng/L for estrogens. The results of the analysis of two sewage treatment plants in the area of Lyon (France) by this method reveal that all the compounds investigated are present in the effluents. The estrogen most frequently detected was estrone, with a median of 26.1 ng/L. The target progestagens were detected with concentrations ranging between 5 and 41 ng/L. Androgens were also present in most of the samples in the range 1-30 ng/L, while the corticosteroids were present only in one plant, with a median of 31.9 ng/L.